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Prueitt RL, Drury NL, Shore RA, Boon DN, Goodman JE. Talc and human cancer: a systematic review of the experimental animal and mechanistic evidence. Crit Rev Toxicol 2024; 54:359-393. [PMID: 38979679 DOI: 10.1080/10408444.2024.2349668] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Accepted: 04/25/2024] [Indexed: 07/10/2024]
Abstract
The potential carcinogenicity of talc has been evaluated in many studies in humans and experimental animals published in the scientific literature over the last several decades, with a number of these studies reporting no associations between talc exposure and any type of cancer. In order to fully understand the current state of the science regarding the potential for talc to induce human cancers, we conducted a comprehensive and systematic review of the available experimental animal and mechanistic evidence (in conjunction with a systematic review of the epidemiology evidence in a companion analysis) to evaluate whether it supports talc as being carcinogenic to humans. We considered study quality and its impact on the interpretation of results and evaluated all types of cancer and all exposure routes. We also evaluated the evidence on the potential for talc to migrate in the body to potential tumor sites. We identified seven experimental animal carcinogenicity studies and 11 mechanistic studies of talc to systematically review. We found that several of the experimental animal carcinogenicity studies of talc have limitations that preclude their sensitivity to detect increases in tumor incidence. Regardless, the studies cover multiple exposure routes, species, and exposure durations, and none indicate that talc is a carcinogen in experimental animals except in rats under conditions of extremely high exposure that likely resulted in lung particle overload, a nonspecific effect of high exposures to poorly soluble particles, and not from any carcinogenic properties of talc. Lung particle overload leading to lung tumor formation has only been observed in rats and not in any other species, including humans. The mechanistic studies indicate that talc is not genotoxic or mutagenic, but can induce some effects that could be events on a possible pathway to carcinogenicity, mainly at high exposures or in in vitro studies with exposures of unclear relevance in vivo, but these effects are not consistent across studies and cell types. This systematic review of the experimental animal carcinogenicity and mechanistic evidence for talc indicates that an association between talc exposure and cancer is not expected in humans. Talc carcinogenicity is not plausible in any species except rats, and only when the exposure conditions are high enough to induce lung particle overload, which is not relevant to human exposures.
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Miao C, Jia P, Luo C, Pang J, Xiao L, Zhang T, Duan J, Li Y, Sun Z. The size-dependent in vivo toxicity of amorphous silica nanoparticles: A systematic review. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 271:115910. [PMID: 38199222 DOI: 10.1016/j.ecoenv.2023.115910] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Revised: 12/25/2023] [Accepted: 12/27/2023] [Indexed: 01/12/2024]
Abstract
The extensive application of amorphous silica nanoparticles (aSiNPs) in recent years has resulted in unavoidable human exposure in daily life, thus raising widespread concerns regarding the safety of aSiNPs on human health. The particle size is one of the important characteristics of nanomaterials that could influence their toxicity. For the reason that particles with smaller sizes possess larger surface area, which may lead to higher surface activity and biological reactivity. However, due to the complexity of experimental conditions and biological systems, the relationship between the particle size and the toxic effect of aSiNPs remains unclear. Therefore, this systematic review aims to investigate how particle size influences the toxic effect of aSiNPs in vivo and to analyze the relevant experimental factors affecting the size-dependent toxicity of aSiNPs in vivo. We found that 83.8% of 35 papers included in the present review came to the conclusion that smaller-sized aSiNPs exhibited stronger toxicity, though a few papers (6 papers) put forward different opinions. The reasons for smaller aSiNPs manifested greater toxicity were summarized. In addition, certain important experimental factors could influence the size-dependent effects and in vivo toxicity of aSiNPs, such as the synthesis method of aSiNPs, disperse medium of aSiNPs, administration route of aSiNPs, species or strain of experimental animals, sex of experimental animals, aggregation/agglomeration and protein corona of aSiNPs.
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Affiliation(s)
- Chen Miao
- Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing 100069, PR China; Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, PR China
| | - Peixi Jia
- Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing 100069, PR China; Beijing Shijitan Hospital Affiliated to Capital Medical University, Beijing 100038, PR China
| | - Chuning Luo
- Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing 100069, PR China; Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, PR China
| | - Jinyan Pang
- Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing 100069, PR China; Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, PR China
| | - Liyan Xiao
- Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing 100069, PR China; Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, PR China
| | - Tanlin Zhang
- Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing 100069, PR China; Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, PR China
| | - Junchao Duan
- Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing 100069, PR China; Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, PR China
| | - Yang Li
- Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing 100069, PR China; Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, PR China.
| | - Zhiwei Sun
- Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing 100069, PR China; Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, PR China.
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Kasai T, Hirai S, Furukawa Y, Misumi K, Takeda T, Goto Y, Takanobu K, Yoneyama K, Yamano S, Senoh H, Umeda Y. Lung carcinogenicity by whole body inhalation exposure to Anatase-type Nano-titanium Dioxide in rats. J Toxicol Sci 2024; 49:359-383. [PMID: 39098045 DOI: 10.2131/jts.49.359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/06/2024]
Abstract
To investigate the carcinogenicity of anatase-type nano-titanium dioxide (aNTiO2), F344/DuCrlCrlj rats were exposed to aNTiO2 aerosol at concentrations of 0, 0.5, 2, and 8 mg/m3. The rats were divided into 2 groups: carcinogenicity study groups were exposed for two years, and satellite study groups were exposed for one year followed by recovery for 1 day, 26 weeks, and 52 weeks after the end of exposure. In the carcinogenicity groups, bronchiolo-alveolar carcinomas were observed in two 8 mg/m3-exposed males, showing an increasing trend by Peto's test. However, this incidence was at the upper limit of JBRC's historical control data. Bronchiolo-alveolar adenomas were observed in 1, 2, 3, and 4 rats of the 0, 0.5, 2, and 8 mg/m3-exposed females and were not statistically significant. However, the incidence in the 8 mg/m3-exposed females exceeded JBRC's historical control data. Therefore, we conclude there is equivocal evidence for the carcinogenicity of aNTiO2 in rats. No lung tumors were observed in the satellite groups. Particle-induced non-neoplastic lesions (alveolar epithelial hyperplasia and focal fibrosis) were observed in exposed males and females in both the carcinogenicity and satellite groups. Increased lung weight and neutrophils of bronchoalveolar lavage fluid were observed in the 8 mg/m3-exposed carcinogenicity groups. The aNTiO2 deposited in the lungs of the satellite group rats was decreased at 26 weeks after the end of exposure compared to 1 day after the end of exposure. At 52 weeks after the end of exposure, the decreased level was the same at 26 weeks after the end of exposure.
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Affiliation(s)
- Tatsuya Kasai
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
| | - Shigeyuki Hirai
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
| | - Yuske Furukawa
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
| | - Kyouhei Misumi
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
| | - Tomoki Takeda
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
| | - Yuko Goto
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
| | - Kenji Takanobu
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
| | - Kengo Yoneyama
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
| | - Shotaro Yamano
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
| | - Hideki Senoh
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
| | - Yumi Umeda
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
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4
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Zhang X, Song Y, Gong H, Wu C, Wang B, Chen W, Hu J, Xiang H, Zhang K, Sun M. Neurotoxicity of Titanium Dioxide Nanoparticles: A Comprehensive Review. Int J Nanomedicine 2023; 18:7183-7204. [PMID: 38076727 PMCID: PMC10710240 DOI: 10.2147/ijn.s442801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Accepted: 11/25/2023] [Indexed: 12/18/2023] Open
Abstract
The increasing use of titanium dioxide nanoparticles (TiO2 NPs) across various fields has led to a growing concern regarding their environmental contamination and inevitable human exposure. Consequently, significant research efforts have been directed toward understanding the effects of TiO2 NPs on both humans and the environment. Notably, TiO2 NPs exposure has been associated with multiple impairments of the nervous system. This review aims to provide an overview of the documented neurotoxic effects of TiO2 NPs in different species and in vitro models. Following exposure, TiO2 NPs can reach the brain, although the specific mechanism and quantity of particles that cross the blood-brain barrier (BBB) remain unclear. Exposure to TiO2 NPs has been shown to induce oxidative stress, promote neuroinflammation, disrupt brain biochemistry, and ultimately impair neuronal function and structure. Subsequent neuronal damage may contribute to various behavioral disorders and play a significant role in the onset and progression of neurodevelopmental or neurodegenerative diseases. Moreover, the neurotoxic potential of TiO2 NPs can be influenced by various factors, including exposure characteristics and the physicochemical properties of the TiO2 NPs. However, a systematic comparison of the neurotoxic effects of TiO2 NPs with different characteristics under various exposure conditions is still lacking. Additionally, our understanding of the underlying neurotoxic mechanisms exerted by TiO2 NPs remains incomplete and fragmented. Given these knowledge gaps, it is imperative to further investigate the neurotoxic hazards and risks associated with exposure to TiO2 NPs.
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Affiliation(s)
- Xing Zhang
- Department of Toxicology, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu, People’s Republic of China
| | - Yuanyuan Song
- Department of Toxicology, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu, People’s Republic of China
| | - Hongyang Gong
- Department of Toxicology, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu, People’s Republic of China
| | - Chunyan Wu
- Department of Toxicology, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu, People’s Republic of China
| | - Binquan Wang
- Department of Toxicology, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu, People’s Republic of China
| | - Wenxuan Chen
- The Second Clinical Medical School, Nanjing Medical University, Nanjing, Jiangsu, People’s Republic of China
| | - Jiawei Hu
- The Second Clinical Medical School, Nanjing Medical University, Nanjing, Jiangsu, People’s Republic of China
| | - Hanhui Xiang
- The Second Clinical Medical School, Nanjing Medical University, Nanjing, Jiangsu, People’s Republic of China
| | - Ke Zhang
- Department of Toxicology, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu, People’s Republic of China
| | - Mingkuan Sun
- Department of Toxicology, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu, People’s Republic of China
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Hojo M, Maeno A, Sakamoto Y, Yamamoto Y, Taquahashi Y, Hirose A, Suzuki J, Inomata A, Nakae D. Time-Course of Transcriptomic Change in the Lungs of F344 Rats Repeatedly Exposed to a Multiwalled Carbon Nanotube in a 2-Year Test. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2105. [PMID: 37513116 PMCID: PMC10383707 DOI: 10.3390/nano13142105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 07/13/2023] [Accepted: 07/17/2023] [Indexed: 07/30/2023]
Abstract
Despite intensive toxicological studies of carbon nanotubes (CNTs) over the last two decades, only a few studies have demonstrated their pulmonary carcinogenicities in chronic animal experiments, and the underlying molecular mechanisms are still unclear. To obtain molecular insights into CNT-induced lung carcinogenicity, we performed a transcriptomic analysis using a set of lung tissues collected from rats in a 2-year study, in which lung tumors were induced by repeated intratracheal instillations of a multiwalled carbon nanotube, MWNT-7. The RNA-seq-based transcriptome identified a large number of significantly differentially expressed genes at Year 0.5, Year 1, and Year 2. Ingenuity Pathway Analysis revealed that macrophage-elicited signaling pathways such as phagocytosis, acute phase response, and Toll-like receptor signaling were activated throughout the experimental period. At Year 2, cancer-related pathways including ERBB signaling and some axonal guidance signaling pathways such as EphB4 signaling were perturbed. qRT-PCR and immunohistochemistry indicated that several key molecules such as Osteopontin/Spp1, Hmox1, Mmp12, and ERBB2 were markedly altered and/or localized in the preneoplastic lesions, suggesting their participation in the induction of lung cancer. Our findings support a scenario of inflammation-induced carcinogenesis and contribute to a better understanding of the molecular mechanism of MWCNT carcinogenicity.
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Affiliation(s)
- Motoki Hojo
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku-ku, Tokyo 169-0073, Japan
| | - Ai Maeno
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku-ku, Tokyo 169-0073, Japan
| | - Yoshimitsu Sakamoto
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku-ku, Tokyo 169-0073, Japan
| | - Yukio Yamamoto
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku-ku, Tokyo 169-0073, Japan
| | - Yuhji Taquahashi
- Division of Cellular and Molecular Toxicology, Center for Biological Safety and Research, National Institute of Health Sciences, 3-25-26 Tono-machi, Kawasaki-ku, Kawasaki 210-9501, Kanagawa, Japan
| | - Akihiko Hirose
- Chemicals Assessment and Research Center, Chemicals Evaluation and Research Institute, Japan, 1-4-25 Koraku, Bunkyo-ku, Tokyo 112-0004, Japan
| | - Jin Suzuki
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku-ku, Tokyo 169-0073, Japan
| | - Akiko Inomata
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku-ku, Tokyo 169-0073, Japan
| | - Dai Nakae
- Department of Medical Sports, Faculty of Health Care and Medical Sports, Teikyo Heisei University, 4-1 Uruido-Minami, Ichihara 290-0193, Chiba, Japan
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6
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Ton TVT, Hong HHL, Kovi RC, Shockley KR, Peddada SD, Gerrish KE, Janardhan KS, Flake G, Stout MD, Sills RC, Pandiri AR. Chronic Inhalation Exposure to Antimony Trioxide Exacerbates the MAPK Signaling in Alveolar Bronchiolar Carcinomas in B6C3F1/N Mice. Toxicol Pathol 2023; 51:39-55. [PMID: 37009983 DOI: 10.1177/01926233231157322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2023]
Abstract
Antimony trioxide (AT) is used as a flame retardant in fabrics and plastics. Occupational exposure in miners and smelters is mainly through inhalation and dermal contact. Chronic inhalation exposure to AT particulates in B6C3F1/N mice and Wistar Han rats resulted in increased incidences and tumor multiplicities of alveolar/bronchiolar carcinomas (ABCs). In this study, we demonstrated Kras (43%) and Egfr (46%) hotspot mutations in mouse lung tumors (n = 80) and only Egfr (50%) mutations in rat lung tumors (n = 26). Interestingly, there were no differences in the incidences of these mutations in ABCs from rats and mice at exposure concentrations that did and did not exceed the pulmonary overload threshold. There was increased expression of p44/42 mitogen-activated protein kinase (MAPK) (Erk1/2) protein in ABCs harboring mutations in Kras and/or Egfr, confirming the activation of MAPK signaling. Transcriptomic analysis indicated significant alterations in MAPK signaling such as ephrin receptor signaling and signaling by Rho-family GTPases in AT-exposed ABCs. In addition, there was significant overlap between transcriptomic data from mouse ABCs due to AT exposure and human pulmonary adenocarcinoma data. Collectively, these data suggest chronic AT exposure exacerbates MAPK signaling in ABCs and, thus, may be translationally relevant to human lung cancers.
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Affiliation(s)
- Thai-Vu T Ton
- National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Hue-Hua L Hong
- National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Ramesh C Kovi
- National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
- Pfizer Inc., Cambridge, Massachusetts, USA
| | - Keith R Shockley
- National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Shyamal D Peddada
- National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Kevin E Gerrish
- National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Kyathanahalli S Janardhan
- National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
- Merck & Co., Inc., Rahway, New Jersey, USA
| | - Gordon Flake
- National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Mathew D Stout
- National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Robert C Sills
- National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Arun R Pandiri
- National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
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7
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Zhang G, Luo W, Yang W, Li S, Li D, Zeng Y, Li Y. The importance of the
IL
‐1 family of cytokines in nanoimmunosafety and nanotoxicology. WIRES NANOMEDICINE AND NANOBIOTECHNOLOGY 2022; 14:e1850. [DOI: 10.1002/wnan.1850] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Revised: 08/03/2022] [Accepted: 08/11/2022] [Indexed: 11/24/2022]
Affiliation(s)
- Guofang Zhang
- Laboratory of Immunology and Nanomedicine Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences Shenzhen China
| | - Wenhe Luo
- Laboratory of Immunology and Nanomedicine Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences Shenzhen China
| | - Wenjie Yang
- Laboratory of Immunology and Nanomedicine Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences Shenzhen China
| | - Su Li
- Laboratory of Immunology and Nanomedicine Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences Shenzhen China
| | - Dongjie Li
- Laboratory of Immunology and Nanomedicine Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences Shenzhen China
| | - Yanqiao Zeng
- Laboratory of Immunology and Nanomedicine Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences Shenzhen China
| | - Yang Li
- Laboratory of Immunology and Nanomedicine Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences Shenzhen China
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8
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Mansoor A, Khurshid Z, Khan MT, Mansoor E, Butt FA, Jamal A, Palma PJ. Medical and Dental Applications of Titania Nanoparticles: An Overview. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:nano12203670. [PMID: 36296859 PMCID: PMC9611494 DOI: 10.3390/nano12203670] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 10/08/2022] [Accepted: 10/09/2022] [Indexed: 05/25/2023]
Abstract
Currently, titanium oxide (TiO2) nanoparticles are successfully employed in human food, drugs, cosmetics, advanced medicine, and dentistry because of their non-cytotoxic, non-allergic, and bio-compatible nature when used in direct close contact with the human body. These NPs are the most versatile oxides as a result of their acceptable chemical stability, lower cost, strong oxidation properties, high refractive index, and enhanced aesthetics. These NPs are fabricated by conventional (physical and chemical) methods and the latest biological methods (biological, green, and biological derivatives), with their advantages and disadvantages in this epoch. The significance of TiO2 NPs as a medical material includes drug delivery release, cancer therapy, orthopedic implants, biosensors, instruments, and devices, whereas their significance as a dental biomaterial involves dentifrices, oral antibacterial disinfectants, whitening agents, and adhesives. In addition, TiO2 NPs play an important role in orthodontics (wires and brackets), endodontics (sealers and obturating materials), maxillofacial surgeries (implants and bone plates), prosthodontics (veneers, crowns, bridges, and acrylic resin dentures), and restorative dentistry (GIC and composites).
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Affiliation(s)
- Afsheen Mansoor
- Department of Dental Material Sciences, School of Dentistry, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad 44080, Pakistan
| | - Zohaib Khurshid
- Department of Prosthodontics and Dental Implantology, College of Dentistry, King Faisal University, Al-Ahsa 31982, Saudi Arabia;
| | - Muhammad Talal Khan
- Department of Dental Biomaterials, Bakhtawar Amin Medical and Dental College, Multan 60650, Pakistan;
| | - Emaan Mansoor
- Islamic International Dental College, Riphah International University, Islamabad 44000, Pakistan;
| | - Faaz Ahmad Butt
- Department of Materials Engineering, NED University of Engineering & Technology, Karachi 74200, Pakistan;
| | - Asif Jamal
- Department of Microbiology, Quaid-i-Azam University, Islamabad 45320, Pakistan;
| | - Paulo J. Palma
- Center for Innovation and Research in Oral Sciences (CIROS), Faculty of Medicine, University of Coimbra, 3000-075 Coimbra, Portugal
- Institute of Endodontics, Faculty of Medicine, University of Coimbra, 3000-075 Coimbra, Portugal
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9
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Lynch HN, Lauer DJ, Thompson WJ, Leleck O, Freid RD, Collins J, Chen K, Ierardi AM, Urban AM, Cappello MA, Boffetta P, Mundt KA. Systematic review of the scientific evidence of the pulmonary carcinogenicity of talc. Front Public Health 2022; 10:989111. [PMID: 36304243 PMCID: PMC9593030 DOI: 10.3389/fpubh.2022.989111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 08/30/2022] [Indexed: 01/26/2023] Open
Abstract
We conducted a systematic review to assess the potential pulmonary carcinogenicity of inhaled talc in humans. Our systematic review methods adhere to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and incorporated aspects from the US Institute of Medicine (IOM) and several United States (US) Environmental Protection Agency (EPA) frameworks for systematic reviews. A comprehensive literature search was conducted. Detailed data abstraction and study quality evaluation, adapting the US Toxic Substances Control Act (TSCA) framework, were central to our analysis. The literature search and selection process identified 23 primary studies that assessed exposure to talc and pulmonary cancer risks in humans (n = 19) and animals (n = 3). Integrating all streams of evidence according to the IOM framework yielded classifications of suggestive evidence of no association between inhaled talc and lung cancer and pleural mesothelioma at human-relevant exposure levels.
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Affiliation(s)
- Heather N. Lynch
- ChemRisk (Stantec), Boston, MA, United States,*Correspondence: Heather N. Lynch
| | | | | | | | | | | | | | | | | | | | - Paolo Boffetta
- Population Sciences, Stony Brook Cancer Center, Stony Brook, NY, United States,Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
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10
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Mundt KA, Santamaria AB, Thompson WJ, Bates CA, Boles C, Dotson GS, Yong M. Carcinogenicity of Poorly Soluble Low Toxicity Particles: Commentary on Epidemiology as a Risk Assessment “Reality Check”. Front Public Health 2022; 10:920032. [PMID: 35903380 PMCID: PMC9315308 DOI: 10.3389/fpubh.2022.920032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 06/20/2022] [Indexed: 11/13/2022] Open
Abstract
Inhaled particles that are poorly soluble or insoluble and of low toxicity (“poorly soluble low toxicity” or “PSLT” particles), can accumulate in the lung and at lung overload levels induce lung cancers in rats. The question of whether PSLT particles increase lung cancer risk in humans is complicated by large differences between rats and humans and the relatively large particle doses administered in animal studies even when compared with heavy human occupational exposures. We review the findings of epidemiological studies on occupational exposure to each of three different PSLT particles (carbon black, talc and taconite). The epidemiological evidence indicates that at even very high occupational exposure levels at which non-malignant respiratory diseases including pneumoconiosis and even talcosis are observed, lung cancer risks appear not to be elevated. Although positive human cancer risks might be predicted based on extrapolation from overload doses in rats to relevant exposures in humans, the epidemiological “reality check” based on the three examples indicates that these PSLT particles are unlikely to increase lung cancer risk in humans even at high occupational levels of exposure. Therefore, we propose that careful evaluation of the epidemiological evidence can serve as a “reality check” for human risk assessment and help balance the risk evaluation process.
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Affiliation(s)
- Kenneth A. Mundt
- Cardno ChemRisk now Stantec, San Francisco, CA, United States
- *Correspondence: Kenneth A. Mundt
| | | | | | | | - Corey Boles
- Cardno ChemRisk now Stantec, San Francisco, CA, United States
| | - G. Scott Dotson
- Cardno ChemRisk now Stantec, San Francisco, CA, United States
| | - Mei Yong
- MY EpiConsulting, Düsseldorf, Germany
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11
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Di Ianni E, Jacobsen NR, Vogel UB, Møller P. Systematic review on primary and secondary genotoxicity of carbon black nanoparticles in mammalian cells and animals. MUTATION RESEARCH. REVIEWS IN MUTATION RESEARCH 2022; 790:108441. [PMID: 36007825 DOI: 10.1016/j.mrrev.2022.108441] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 08/17/2022] [Accepted: 08/19/2022] [Indexed: 01/01/2023]
Abstract
Carbon black exposure causes oxidative stress, inflammation and genotoxicity. The objective of this systematic review was to assess the contributions of primary (i.e. direct formation of DNA damage) and secondary genotoxicity (i.e., DNA lesions produced indirectly by inflammation) to the overall level of DNA damage by carbon black. The database is dominated by studies that have measured DNA damage by the comet assay. Cell culture studies indicate a genotoxic action of carbon black, which might be mediated by oxidative stress. Many in vivo studies originate from one laboratory that has investigated the genotoxic effects of Printex 90 in mice by intra-tracheal instillation. Meta-analysis and pooled analysis of these results demonstrate that Printex 90 exposure is associated with a slightly increased level of DNA strand breaks in bronchoalveolar lavage cells and lung tissue. Other types of genotoxic damage have not been investigated as thoroughly as DNA strand breaks, although there is evidence to suggest that carbon black exposure might increase the mutation frequency and cytogenetic endpoints. Stratification of studies according to concurrent inflammation and DNA damage does not indicate that carbon black exposure gives rise to secondary genotoxicity. Even substantial pulmonary inflammation is at best only associated with a weak genotoxic response in lung tissue. In conclusion, the review indicates that nanosized carbon black is a weak genotoxic agent and this effect is more likely to originate from a primary genotoxic mechanism of action, mediated by e.g., oxidative stress, than inflammation-driven (secondary) genotoxicity.
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Affiliation(s)
- Emilio Di Ianni
- The National Research Centre for the Working Environment, Lersø Parkalle 105, DK-2100 Copenhagen Ø, Denmark
| | - Nicklas Raun Jacobsen
- The National Research Centre for the Working Environment, Lersø Parkalle 105, DK-2100 Copenhagen Ø, Denmark
| | - Ulla Birgitte Vogel
- The National Research Centre for the Working Environment, Lersø Parkalle 105, DK-2100 Copenhagen Ø, Denmark; National Food Institute, Technical University of Denmark, Kemitorvet, Bygning 202, DK-2800 Kgs Lyngby, Denmark
| | - Peter Møller
- Department of Public Health, Section of Environmental Health, University of Copenhagen, Øster Farimagsgade 5A, DK-1014 Copenhagen, Denmark.
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12
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Visser M, Gosens I, Bard D, van Broekhuizen P, Janer G, Kuempel E, Riediker M, Vogel U, Dekkers S. Towards health-based nano reference values (HNRVs) for occupational exposure: Recommendations from an expert panel. NANOIMPACT 2022; 26:100396. [PMID: 35560294 PMCID: PMC10617652 DOI: 10.1016/j.impact.2022.100396] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 02/23/2022] [Accepted: 03/11/2022] [Indexed: 06/15/2023]
Abstract
Unique physicochemical characteristics of engineered nanomaterials (ENMs) suggest the need for nanomaterial-specific occupational exposure limits (OELs). Setting these limits remains a challenge. Therefore, the aim of this study was to set out a framework to evaluate the feasibility of deriving advisory health-based occupational limit values for groups of ENMs, based on scientific knowledge. We have used an expert panel approach to address three questions: 1) What ENM-categories should be distinguished to derive advisory health-based occupational limit values (or health-based Nano Reference Values, HNRVs) for groups of ENMs? 2) What evidence would be needed to define values for these categories? And 3) How much effort would it take to achieve this? The panel experts distinguished six possible categories of HNRVs: A) WHO-fiber-like high aspect ratio ENMs (HARNs), B) Non-WHO-fiber-like HARNs and other non-spheroidal ENMs, C) readily soluble spheroidal ENMs, D) biopersistent spheroidal ENMs with unknown toxicity, E) biopersistent spheroidal ENMs with substance-specific toxicity and F) biopersistent spheroidal ENMs with relatively low substance-specific toxicity. For category A, the WHO-fiber-like HARNs, agreement was reached on criteria defining this category and the approach of using health-based risk estimates for asbestos to derive the HNRV. For category B, a quite heterogeneous category, more toxicity data are needed to set an HNRV. For category C, readily soluble spheroidal ENMs, using the OEL of their molecular or ionic counterpart would be a good starting point. For the biopersistent ENMs with unknown toxicity, HNRVs cannot be applied as case-by-case testing is required. For the other biopersistent ENMs in category E and F, we make several recommendations that can facilitate the derivation of these HNRVs. The proposed categories and recommendations as outlined by this expert panel can serve as a reference point for derivation of HNRVs when health-based OELs for ENMs are not yet available.
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Affiliation(s)
- Maaike Visser
- National Institute for Public Health and the Environment, Bilthoven, the Netherlands.
| | - Ilse Gosens
- National Institute for Public Health and the Environment, Bilthoven, the Netherlands
| | - Delphine Bard
- Health and Safety Executive (HSE) Science and Research Centre, Buxton, United Kingdom
| | | | - Gemma Janer
- Leitat Technological Center, Barcelona, Spain
| | - Eileen Kuempel
- National Institute for Occupational Safety and Health, Cincinnati, OH, USA
| | - Michael Riediker
- Swiss Centre for Occupational and Environmental Health, Winterthur, Switzerland
| | - Ulla Vogel
- National Research Centre for the Working Environment, Copenhagen, Denmark
| | - Susan Dekkers
- National Institute for Public Health and the Environment, Bilthoven, the Netherlands
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13
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Ladics GS, Price O, Kelkar S, Herkimer S, Anderson S. A Weight-of-the-Evidence Approach for Evaluating, in Lieu of Animal Studies, the Potential of a Novel Polysaccharide Polymer to Produce Lung Overload. Chem Res Toxicol 2021; 34:1430-1444. [PMID: 33881304 DOI: 10.1021/acs.chemrestox.0c00301] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The United States Environmental Protection Agency (EPA) is concerned about the respiratory effects caused by respirable particles of water-insoluble high molecular weight polymers. The EPA has proposed a tiered approach to evaluate polymer lung overload, a kinetic event. Kinetic polymer lung overload in itself is not necessarily adverse, however, inhalation of respirable particulate matter can have adverse effects (i.e., inflammation, fibrosis, etc.). If Tier I testing demonstrates that particles may reach the distal lung (i.e., a non-negligible amount of respirable particles/droplets ≤10 μm in diameter and lack of biosolubility), then animal inhalation testing in Tiers II-IV would be requested. In silico, in chemico, and in vitro alternatives should be considered versus in vivo testing for animal welfare purposes. An in chemico measure of biosolubility was used to demonstrate that a novel α-1,3-glucan polysaccharide, made by enzymatic polymerization of glucose from sucrose, is biosoluble and fits a simple exponential decay model with a half-life on the order of 66 days. The multiple-path particle dosimetry (MPPD) in silico model was used to predict lung burden for the novel α-1,3-glucan polysaccharide. MPPD was validated with measurements in rats exposed to a toner particulate and showed good agreement with lung burden measurements. A simulated 24 month rat exposure yielded 10-20 times less lung burden for the polysaccharide compared to the toner at equivalent exposure concentrations. The MPPD model was refined to include biosolubility data for the polysaccharide polymer. Data for amorphous silica were used to validate the clearance model, and the model incorporating dissolution predicted the amorphous silica lung burden within 20% of measured values. Human equivalent concentrations (HECs) were calculated for each toner rat exposure concentration. HECs were also determined for the polysaccharide at exposure concentrations yielding the same predicted internal doses as the toner. The in vitro, in chemico and in silico studies described here for the novel polysaccharide provide a useful weight of evidence approach in the absence of animal studies for the evaluation of polymer substances where polymer lung overload may be a concern.
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Affiliation(s)
- Gregory S Ladics
- IFF, 200 Powder Mill Road, Bldg. 353, Wilmington, Delaware 19803, United States
| | - Owen Price
- Applied Research Associates, Inc., 801 N. Quincy Street, Suite 700, Arlington, Virginia 22203, United States
| | - Shantanu Kelkar
- IFF, 200 Powder Mill Road, Bldg. 353, Wilmington, Delaware 19803, United States
| | - Scott Herkimer
- IFF, 200 Powder Mill Road, Bldg. 353, Wilmington, Delaware 19803, United States
| | - Shawn Anderson
- IFF, 200 Powder Mill Road, Bldg. 353, Wilmington, Delaware 19803, United States
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14
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Willhite CC, Karyakina NA, Nordheim E, Arnold I, Armstrong V, Momoli F, Shilnikova NS, Yenugadhati N, Krewski D. The REACH registration process: A case study of metallic aluminium, aluminium oxide and aluminium hydroxide. Neurotoxicology 2020; 83:166-178. [PMID: 33290785 DOI: 10.1016/j.neuro.2020.12.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The European Union's REACH Regulation requires determination of potential health and environmental effects of chemicals in commerce. The present case study examines the application of REACH guidance for health hazard assessments of three high production volume (HPV) aluminium (Al) substances: metallic aluminium, aluminium oxide, and aluminium hydroxide. Among the potential adverse health consequences of aluminium exposure, neurotoxicity is one of the most sensitive targets of Al toxicity and the most critical endpoint. This case study illustrates integration of data from multiple lines of evidence into REACH weight of evidence evaluations. This case study then explains how those results support regulatory decisions on classification and labelling. Challenges in the REACH appraisal of Al compounds include speciation, solubility and bioavailability, application of assessment factors, read-across rationale and differences with existing regulatory standards. Lessons learned from the present case study relate to identification and evaluation of toxicologic and epidemiologic data; assessing data relevance and reliability; development of derived no-effect levels (DNELs); addressing data gaps and preparation of chemical safety reports.
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Affiliation(s)
| | - Nataliya A Karyakina
- Risk Sciences International, Ottawa, Canada; McLaughlin Centre for Population Health Risk Assessment, University of Ottawa, Ottawa, Canada.
| | | | - Ian Arnold
- International Aluminium Institute, London, United Kingdom; Occupational Health Program, Faculty of Medicine, McGill University, Montreal, QC, Canada
| | | | - Franco Momoli
- Risk Sciences International, Ottawa, Canada; McLaughlin Centre for Population Health Risk Assessment, University of Ottawa, Ottawa, Canada; Faculty of Medicine, School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada
| | - Natalia S Shilnikova
- Risk Sciences International, Ottawa, Canada; McLaughlin Centre for Population Health Risk Assessment, University of Ottawa, Ottawa, Canada
| | - Nagarajkumar Yenugadhati
- Risk Sciences International, Ottawa, Canada; Department of Epidemiology and Biostatistics, College of Public Health and Health Informatics, King Saud bin Abdul-Aziz University for Health Sciences, Riyadh, Saudi Arabia
| | - Daniel Krewski
- Risk Sciences International, Ottawa, Canada; McLaughlin Centre for Population Health Risk Assessment, University of Ottawa, Ottawa, Canada; Faculty of Medicine, School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada
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15
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Braakhuis HM, Gosens I, Heringa MB, Oomen AG, Vandebriel RJ, Groenewold M, Cassee FR. Mechanism of Action of TiO 2: Recommendations to Reduce Uncertainties Related to Carcinogenic Potential. Annu Rev Pharmacol Toxicol 2020; 61:203-223. [PMID: 32284010 DOI: 10.1146/annurev-pharmtox-101419-100049] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The Risk Assessment Committee of the European Chemicals Agency issued an opinion on classifying titanium dioxide (TiO2) as a suspected human carcinogen upon inhalation. Recent animal studies indicate that TiO2 may be carcinogenic through the oral route. There is considerable uncertainty on the carcinogenicity of TiO2, which may be decreased if its mechanism of action becomes clearer. Here we consider adverse outcome pathways and present the available information on each of the key events (KEs). Inhalation exposure to TiO2 can induce lung tumors in rats via a mechanism that is also applicable to other poorly soluble, low-toxicity particles. To reduce uncertainties regarding human relevance, we recommend gathering information on earlier KEs such as oxidative stress in humans. For oral exposure, insufficient information is available to conclude whether TiO2 can induce intestinal tumors. An oral carcinogenicity study with well-characterized (food-grade) TiO2 is needed, including an assessment of toxicokinetics and early KEs.
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Affiliation(s)
- Hedwig M Braakhuis
- National Institute for Public Health and the Environment (RIVM), 3720 BA Bilthoven, The Netherlands;
| | - Ilse Gosens
- National Institute for Public Health and the Environment (RIVM), 3720 BA Bilthoven, The Netherlands;
| | - Minne B Heringa
- National Institute for Public Health and the Environment (RIVM), 3720 BA Bilthoven, The Netherlands; .,Current affiliation: Reckitt Benckiser, 1118 BH Schiphol, The Netherlands
| | - Agnes G Oomen
- National Institute for Public Health and the Environment (RIVM), 3720 BA Bilthoven, The Netherlands;
| | - Rob J Vandebriel
- National Institute for Public Health and the Environment (RIVM), 3720 BA Bilthoven, The Netherlands;
| | - Monique Groenewold
- National Institute for Public Health and the Environment (RIVM), 3720 BA Bilthoven, The Netherlands;
| | - Flemming R Cassee
- National Institute for Public Health and the Environment (RIVM), 3720 BA Bilthoven, The Netherlands; .,Institute for Risk Assessment Sciences, University of Utrecht, 3508 TD Utrecht, The Netherlands
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16
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Morgan J, Bell R, Jones AL. Endogenous doesn't always mean innocuous: a scoping review of iron toxicity by inhalation. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2020; 23:107-136. [PMID: 32106786 DOI: 10.1080/10937404.2020.1731896] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Ambient air pollution is a leading risk factor for the global burden of disease. One possible pathway of particulate matter (PM)-induced toxicity is through iron (Fe), the most abundant metal in the atmosphere. The aim of the review was to consider the complexity of Fe-mediated toxicity following inhalation exposure focusing on the chemical and surface reactivity of Fe as a transition metal and possible pathways of toxicity via reactive oxygen species (ROS) generation as well as considerations of size, morphology, and source of PM. A broad term search of 4 databases identified 2189 journal articles and reports examining exposure to Fe via inhalation in the past 10 years. These were sequentially analyzed by title, abstract and full-text to identify 87 articles publishing results on the toxicity of Fe-containing PM by inhalation or instillation to the respiratory system. The remaining 87 papers were examined to summarize research dealing with in vitro, in vivo and epidemiological studies involving PM containing Fe or iron oxide following inhalation or instillation. The major findings from these investigations are summarized and tabulated. Epidemiological studies showed that exposure to Fe oxide is correlated with an increased incidence of cancer, cardiovascular diseases, and several respiratory diseases. Iron PM was found to induce inflammatory effects in vitro and in vivo and to translocate to remote locations including the brain following inhalation. A potential pathway for the PM-containing Fe-mediated toxicity by inhalation is via the generation of ROS which leads to lipid peroxidation and DNA and protein oxidation. Our recommendations include an expansion of epidemiological, in vivo and in vitro studies, integrating research improvements outlined in this review, such as the method of particle preparation, cell line type, and animal model, to enhance our understanding of the complex biological interactions of these particles.
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Affiliation(s)
- Jody Morgan
- Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, Australia
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, Australia
| | - Robin Bell
- School of Medicine and Public Health, University of Newcastle, Newcastle, Australia
| | - Alison L Jones
- Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, Australia
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, Australia
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17
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Driscoll KE, Borm PJA. Expert workshop on the hazards and risks of poorly soluble low toxicity particles. Inhal Toxicol 2020; 32:53-62. [DOI: 10.1080/08958378.2020.1735581] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Kevin E. Driscoll
- Healthcare Innovation Partners, Princeton, NJ, USA
- Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ, USA
| | - Paul J. A. Borm
- Nanoconsult BV, Meerssen, The Netherlands
- Dusseldorf University, Dusseldorf, Germany
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18
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The mTOR/GCLc/GSH Pathway Mediates the Dose-Dependent Bidirectional Regulation of ROS Induced by TiO 2NPs in Neurogenic Cells. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019. [DOI: 10.1155/2019/7621561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Objective. The effect of TiO2NP exposure on the nervous system and the underlying mechanism remain unclear. The antioxidant effect of TiO2NPs at a low dose was newly found in our study, which was different from the effect at high dose. This study is aimed at exploring the mechanism underlying the antioxidant effects of TiO2NPs at low dose and the induction of ROS accumulation by TiO2NPs at high dose in neurogenic cell lines.Methods. We measured the changes in key molecules in the ROS regulation pathway by western blotting, flow cytometry, and commercial assay kits, and these key molecules were further evaluated to verify their interactions and roles using SH-SY5Y, U251, and SK-N-SH cell lines treated with TiO2NPs.Results. Our results showed that the weak antioxidant effect at low dose was caused by mTOR/GCLc-induced GSH overproduction and GSH-Px activity impairment. ROS accumulation at high dose was caused by a mTOR/GCLc-mediated decrease in GSH production, GSH-Px activity impairment, and dramatic ROS production. Furthermore, we found that the ROS species were mainly O2-⋅, and that SOD played a crucial role in reducing O2-⋅levels before the mTOR protein was activated.Conclusion. We revealed the mechanism underlying the bidirectional regulation of ROS induced by TiO2NPs at different doses in neurogenic cell lines. Our study emphasized the potential neurotoxic effects of NPs at low dose, which should arouse concern about their safety.
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19
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Flaccavento A, Pecoraro R, Scalisi EM, Messina G, Salvaggio A, Impellizzeri G, Lombardo BM, Brundo MV. Morphostructural and immunohistochemical study for evaluation of nano‐TiO
2
toxicity in
Armadillo officinalis
Duméril, 1816 (Crustacea, Isopoda, Oniscidea). Microsc Res Tech 2019; 83:297-303. [DOI: 10.1002/jemt.23413] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 10/15/2019] [Accepted: 10/17/2019] [Indexed: 01/08/2023]
Affiliation(s)
- Alessia Flaccavento
- Department of Biological, Geological and Environmental ScienceUniversity of Catania Catania Italy
| | - Roberta Pecoraro
- Department of Biological, Geological and Environmental ScienceUniversity of Catania Catania Italy
| | - Elena Maria Scalisi
- Department of Biological, Geological and Environmental ScienceUniversity of Catania Catania Italy
| | - Giuseppina Messina
- Department of Biological, Geological and Environmental ScienceUniversity of Catania Catania Italy
| | - Antonio Salvaggio
- Experimental Zooprophylactic Institute of Sicily “A. Mirri” Catania Italy
| | | | - Bianca Maria Lombardo
- Department of Biological, Geological and Environmental ScienceUniversity of Catania Catania Italy
| | - Maria Violetta Brundo
- Department of Biological, Geological and Environmental ScienceUniversity of Catania Catania Italy
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20
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Prasath S, Palaniappan K. Is using nanosilver mattresses/pillows safe? A review of potential health implications of silver nanoparticles on human health. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2019; 41:2295-2313. [PMID: 30671691 DOI: 10.1007/s10653-019-00240-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 01/02/2019] [Indexed: 06/09/2023]
Abstract
Human exposure to engineered nanoparticles has become inevitable in today's extensive commercial use and large-scale production of engineered nanoparticles. Even though several studies have characterised the exposure to nanomaterials during wakeful state (related to occupational exposures and exposures from commercially available particles), very few studies on human exposure during sleep exist. As the study of exposure to all possible nanomaterials during sleep is extensive, this study focuses on exposure to specifically silver nanoparticles which are present in beddings and mattresses. The reasoning behind the use of silver nanoparticles in bedding and related materials, possible routes of entry to various population groups in several sleep positions, exposure characterisation and toxicity potential of such silver nanoparticles are reviewed in this study. The toxicity potential of silver nanoparticles in vivo tests with relation to mammals and in vitro tests on human cells has been tabulated to understand the risks associated during oral, dermal and inhalation exposure to silver nanoparticles. The exposure to humans with regard to dermal absorption and oral intake has been summarised. Although potential inhalation exposure to silver nanoparticles is increasing, only a few studies address the possible toxic effect of inhaled silver particles. Determination of exposure to silver nanoparticles in beddings is a topic that has been less researched, and this review aims to provide background information for future research and help establish a comprehensive risk assessment during sleep in the times of increasing usage of nanoparticles in our daily activities. Despite the current limitations of our understanding, risk assessments must utilise the available data and apply extrapolation procedures in the face of uncertainty, in order to address the needs of regulatory programs. This would enable safe use of the antimicrobial properties of silver nanoparticles without negatively impacting human health. Until then, it would be better to adopt a conservative approach on the usage of silver nanoparticles in daily used commercial items.
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Affiliation(s)
| | - Kavitha Palaniappan
- University of Newcastle, Callahan, Australia
- University of Newcastle, Singapore, Singapore
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21
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Skubalova Z, Michalkova H, Michalek P, Strmiska V, Guran R, Merlos Rodrigo MA, Castkova K, Hynek D, Pekarik V, Zitka O, Adam V, Heger Z. Prevalent anatase crystalline phase increases the cytotoxicity of biphasic titanium dioxide nanoparticles in mammalian cells. Colloids Surf B Biointerfaces 2019; 182:110391. [DOI: 10.1016/j.colsurfb.2019.110391] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 07/01/2019] [Accepted: 07/23/2019] [Indexed: 11/28/2022]
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22
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Kawai S, Niwano M, Sato M. A risk assessment framework for self-management of poorly soluble low toxic nanomaterials. Heliyon 2019; 5:e02165. [PMID: 31453392 PMCID: PMC6700412 DOI: 10.1016/j.heliyon.2019.e02165] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 07/18/2019] [Accepted: 07/24/2019] [Indexed: 11/28/2022] Open
Abstract
The safety of nanomaterials is still being debated and the risk should be assessed using the latest available information. As for poorly soluble low toxic (PSLT) nanomaterials, the US National Institute for Occupational Safety and Health estimated the occupational exposure limit (OEL) for titanium dioxide (TiO2) based on a particle surface area (SA) metric. The Organisation for Economic Co-operation and Development (OECD) suggested a tiered exposure assessment approach. This article proposes a risk assessment framework for self-management of PSLT particles. Lung burden (described in SA units), which had positive correlation with low observed adverse effect levels for PSLT particles, is chosen as the dose metric. In-house OEL is determined for individual workplaces. For materials with limited data, we suggest evaluating in-house OEL by utilizing the no observed adverse effect level (NOAEL) for TiO2, as a representative PSLT nanomaterial. As for the exposure assessment, workplace concentration is first measured with simple equipment (ex. optical particle counter, OPC), and respirator performance is taken into account if it is unavoidable as a last resort. This framework enables efficient risk assessment for PSLT particles by assuming worst cases for each step, and considering the particle characteristics and operational conditions in each workplace.
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Affiliation(s)
- Satomi Kawai
- Environmental Health Science Laboratory, Sumitomo Chemical Co., Ltd., 3-1-98, Kasugadenaka, Konohana-ku, Osaka, 554-8558, Japan
| | - Masanori Niwano
- Environmental Health Science Laboratory, Sumitomo Chemical Co., Ltd., 3-1-98, Kasugadenaka, Konohana-ku, Osaka, 554-8558, Japan
| | - Masayuki Sato
- Environmental Health Science Laboratory, Sumitomo Chemical Co., Ltd., 3-1-98, Kasugadenaka, Konohana-ku, Osaka, 554-8558, Japan
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23
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Li W, Pauluhn J. Re-defining kinetic lung overload: Time for new paradigms. Toxicol Lett 2018; 295:212-219. [PMID: 29966747 DOI: 10.1016/j.toxlet.2018.06.1222] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 06/27/2018] [Accepted: 06/27/2018] [Indexed: 10/28/2022]
Abstract
This paper compares two previously published 13-week inhalation studies with poorly soluble, low-toxicity particles (PSLTs) in rats to identify the unifying key metric of kinetic lung overload. The PSLTs compared are Multi-Walled Carbon Nanotubes (MWCNT) and black iron oxide (Fe3O4, magnetite). Their material densities and related displacement volumes differ approximately 30-fold. This offers an opportunity for analyzing the impact of the PSLT-density of agglomerates on endpoints currently conceived to be involved in kinetic lung overload. Corpuscular volumes and counts of cells retrieved by bronchoalveolar lavage (BAL) are analyzed to interrelate modeled cumulative lung burdens of solid aerosol to predict the no observed adverse effect concentration (NOAEC) and range of conditions causing various degrees of kinetic lung overload up to and beyond the maximum tolerated cumulative dose (MTD). Both descriptors are a reflection of accumulated lung burdens and, by design, bracket repeated exposure inhalation studies with PSLTs. This comparative analysis of high- and low-density PSLTs reveals that the leading adverse outcome pathway (AOP) is caused by a markedly increased pool-size of BAL-cells rather than any increased corpuscular volume of cells. The overload-related increased pool-size of BAL-cells is shown to be the dependent variable for the prorated increased elimination half-time of PSLTs. This interrelationship was used to predict the exposure concentrations for attaining a NOAEC and MTD of guideline-based repeated exposure inhalation studies with PSLTs. Earlier approaches suggesting a loss of the migratory capabilities of particle-laden, enlarged alveolar macrophages to be the cause for any increased elimination half-time of PSLTs could not be confirmed. In summary, kinetic modeling provides a versatile means to predict the cornerstones of repeated inhalation studies with PSLTs on rats. Such possibilities leverage adjustment of studies from different sources to identical degrees of kinetic overload. They also facilitate and foster AOP-facilitated read-across approaches. The course taken enables risk assessors to better differentiate lung pathologies caused by generic lung overload and substance-specific pathologies.
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Affiliation(s)
- Wenli Li
- 14th Military Medical University, Xi'an, China
| | - Juergen Pauluhn
- 14th Military Medical University, Xi'an, China; Hannover Medical School, Hannover, Germany.
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Schulte PA, Kuempel ED, Drew NM. Characterizing risk assessments for the development of occupational exposure limits for engineered nanomaterials. Regul Toxicol Pharmacol 2018; 95:207-219. [PMID: 29574195 PMCID: PMC6075708 DOI: 10.1016/j.yrtph.2018.03.018] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 03/05/2018] [Accepted: 03/20/2018] [Indexed: 12/16/2022]
Abstract
The commercialization of engineered nanomaterials (ENMs) began in the early 2000's. Since then the number of commercial products and the number of workers potentially exposed to ENMs is growing, as is the need to evaluate and manage the potential health risks. Occupational exposure limits (OELs) have been developed for some of the first generation of ENMs. These OELs have been based on risk assessments that progressed from qualitative to quantitative as nanotoxicology data became available. In this paper, that progression is characterized. It traces OEL development through the qualitative approach of general groups of ENMs based primarily on read-across with other materials to quantitative risk assessments for nanoscale particles including titanium dioxide, carbon nanotubes and nanofibers, silver nanoparticles, and cellulose nanocrystals. These represent prototypic approaches to risk assessment and OEL development for ENMs. Such substance-by-substance efforts are not practical given the insufficient data for many ENMs that are currently being used or potentially entering commerce. Consequently, categorical approaches are emerging to group and rank ENMs by hazard and potential health risk. The strengths and limitations of these approaches are described, and future derivations and research needs are discussed. Critical needs in moving forward with understanding the health effects of the numerous EMNs include more standardized and accessible quantitative data on the toxicity and physicochemical properties of ENMs.
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Affiliation(s)
- P A Schulte
- National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, United States.
| | - E D Kuempel
- National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, United States
| | - N M Drew
- National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, United States
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An updated review of the genotoxicity of respirable crystalline silica. Part Fibre Toxicol 2018; 15:23. [PMID: 29783987 PMCID: PMC5963024 DOI: 10.1186/s12989-018-0259-z] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 05/09/2018] [Indexed: 12/22/2022] Open
Abstract
Human exposure to (certain forms of) crystalline silica (CS) potentially results in adverse effects on human health. Since 1997 IARC has classified CS as a Group 1 carcinogen [1], which was confirmed in a later review in 2012 [2]. The genotoxic potential and mode of genotoxic action of CS was not conclusive in either of the IARC reviews, although a proposal for mode of actions was made in an extensive review of the genotoxicity of CS by Borm, Tran and Donaldson in 2011 [3]. The present study identified 141 new papers from search strings related to genotoxicity of respirable CS (RCS) since 2011 and, of these, 17 relevant publications with genotoxicity data were included in this detailed review. Studies on in vitro genotoxic endpoints primarily included micronucleus (MN) frequency and % fragmented DNA as measured in the comet assay, and were mostly negative, apart from two studies using primary or cultured macrophages. In vivo studies confirmed the role of persistent inflammation due to quartz surface toxicity leading to anti-oxidant responses in mice and rats, but DNA damage was only seen in rats. The role of surface characteristics was strengthened by in vitro and in vivo studies using aluminium or hydrophobic treatment to quench the silanol groups on the CS surface. In conclusion, the different modes of action of RCS-induced genotoxicity have been evaluated in a series of independent, adequate studies since 2011. Earlier conclusions on the role of inflammation driven by quartz surface in genotoxic and carcinogenic effects after inhalation are confirmed and findings support a practical threshold. Whereas classic in vitro genotoxicity studies confirm an earlier no-observed effect level (NOEL) in cell cultures of 60-70 μg/cm2, transformation frequency in SHE cells suggests a lower threshold around 5 μg/cm2. Both levels are only achieved in vivo at doses (2–4 mg) beyond in vivo doses (> 200 μg) that cause persistent inflammation and tissue remodelling in the rat lung.
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Zulkifli A, Abidin EZ, Abidin NZ, Amer Nordin AS, Praveena SM, Syed Ismail SN, Rasdi I, Karuppiah K, Rahman AA. Electronic cigarettes: a systematic review of available studies on health risk assessment. REVIEWS ON ENVIRONMENTAL HEALTH 2018; 33:43-52. [PMID: 27101543 DOI: 10.1515/reveh-2015-0075] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 02/09/2016] [Indexed: 06/05/2023]
Abstract
OBJECTIVE This paper primarily aimed to review articles which specifically quantified the risk of electronic cigarette's (e-cigarette) usage via the health risk assessment (HRA) approach. METHODS Systematic literature searches were conducted using PubMed search engine databases. Search terms such as "electronic cigarette", "e-cigarette", "electronic nicotine delivery systems", "electronic cigarette liquid", "electronic cigarette vapors", and "health risk assessment" were used to identify the relevant articles to be included in this review. To enable comparison, hazard quotient (HQ) and lifetime cancer risk (LCR) for the chemicals measured in the selected articles were calculated for three of the articles using the formula: [1] HQ=average daily dose (ADD)/reference dose (RfD) or exposure air concentration (EC)/reference concentration (RfC); [2] LCR=lifetime average daily dose (LADD) × cancer slope factor (CSF) or exposure air concentration (EC) × inhalation unit risk (IUR). RESULTS Four articles pertaining to HRA of e-cigarettes were critically reviewed, three of the papers focused on specific chemicals namely nicotine, propylene glycol (PG), glycerol and 1,2-propanediol, while one article evaluated the health risks posed by heavy metals contained in e-cigarettes. The calculated HQs for the chemicals in this review had large variations. HQs of the six chemicals, i.e. nicotine, PG, glycerol, cadmium, ethylene glycol, nickel, aluminum and titanium, were found to have the potential to contribute to non-carcinogenic health risks. None of the LCR calculated had risks exceeding the acceptable limit. CONCLUSION There are limited HRA studies and the ones that were available provided inconsistent scientific evidences on the health risk characterization arising from the usage of e-cigarettes. As such, there is a need to perform more studies on HRA of e-cigarettes by using uniformed and comprehensive steps and similar reference threshold levels of exposures.
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Affiliation(s)
- Aziemah Zulkifli
- Faculty of Medicine and Health Sciences, Department of Environmental and Occupational Health, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Emilia Zainal Abidin
- Faculty of Medicine and Health Sciences, Department of Environmental and Occupational Health, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia, Phone: +603 89472643, Fax: +603 89472395
| | - Najihah Zainol Abidin
- Faculty of Medicine and Health Sciences, Department of Environmental and Occupational Health, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Amer Siddiq Amer Nordin
- Faculty of Medicine, Department of Psychological Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Sarva Mangala Praveena
- Faculty of Medicine and Health Sciences, Department of Environmental and Occupational Health, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Sharifah Norkhadijah Syed Ismail
- Faculty of Medicine and Health Sciences, Department of Environmental and Occupational Health, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Irniza Rasdi
- Faculty of Medicine and Health Sciences, Department of Environmental and Occupational Health, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Karmegam Karuppiah
- Faculty of Medicine and Health Sciences, Department of Environmental and Occupational Health, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Anita Abd Rahman
- Faculty of Medicine and Health Sciences, Department of Community Health, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
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Chaudhuri I, Fruijtier-Pölloth C, Ngiewih Y, Levy L. Evaluating the evidence on genotoxicity and reproductive toxicity of carbon black: a critical review. Crit Rev Toxicol 2017; 48:143-169. [DOI: 10.1080/10408444.2017.1391746] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Ishrat Chaudhuri
- Safety, Health and Environment, Cabot Corporation, Billerica, MA, USA
| | | | | | - Len Levy
- School of Water, Energy and Environment, Cranfield University, Cranfield, UK
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Drew NM, Kuempel ED, Pei Y, Yang F. A quantitative framework to group nanoscale and microscale particles by hazard potency to derive occupational exposure limits: Proof of concept evaluation. Regul Toxicol Pharmacol 2017; 89:253-267. [PMID: 28789940 PMCID: PMC5875420 DOI: 10.1016/j.yrtph.2017.08.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 07/18/2017] [Accepted: 08/03/2017] [Indexed: 11/28/2022]
Abstract
The large and rapidly growing number of engineered nanomaterials (ENMs) presents a challenge to assessing the potential occupational health risks. An initial database of 25 rodent studies including 1929 animals across various experimental designs and material types was constructed to identify materials that are similar with respect to their potency in eliciting neutrophilic pulmonary inflammation, a response relevant to workers. Doses were normalized across rodent species, strain, and sex as the estimated deposited particle mass dose per gram of lung. Doses associated with specific measures of pulmonary inflammation were estimated by modeling the continuous dose-response relationships using benchmark dose modeling. Hierarchical clustering was used to identify similar materials. The 18 nanoscale and microscale particles were classified into four potency groups, which varied by factors of approximately two to 100. Benchmark particles microscale TiO2 and crystalline silica were in the lowest and highest potency groups, respectively. Random forest methods were used to identify the important physicochemical predictors of pulmonary toxicity, and group assignments were correctly predicted for five of six new ENMs. Proof-of-concept was demonstrated for this framework. More comprehensive data are needed for further development and validation for use in deriving categorical occupational exposure limits.
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Affiliation(s)
- Nathan M Drew
- National Institute for Occupational Safety and Health (NIOSH), Nanotechnology Research Center (NTRC), Cincinnati, OH 45226, USA.
| | - Eileen D Kuempel
- National Institute for Occupational Safety and Health (NIOSH), Nanotechnology Research Center (NTRC), Cincinnati, OH 45226, USA
| | - Ying Pei
- West Virginia University, Department of Industrial and Management System Engineering, Morgantown, WV 26506, USA
| | - Feng Yang
- West Virginia University, Department of Industrial and Management System Engineering, Morgantown, WV 26506, USA
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29
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Pauluhn J. Kinetic modeling of the retention and fate of inhaled cerium oxide nanoparticles in rats: The cumulative displacement volume of agglomerates determines the outcome. Regul Toxicol Pharmacol 2017; 86:319-331. [DOI: 10.1016/j.yrtph.2017.03.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 03/24/2017] [Accepted: 03/30/2017] [Indexed: 10/19/2022]
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30
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Warheit DB, Kreiling R, Levy LS. Relevance of the rat lung tumor response to particle overload for human risk assessment-Update and interpretation of new data since ILSI 2000. Toxicology 2016; 374:42-59. [PMID: 27876671 DOI: 10.1016/j.tox.2016.11.013] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 11/16/2016] [Accepted: 11/17/2016] [Indexed: 11/18/2022]
Abstract
The relevance of particle-overload related lung tumors in rats for human risk assessment following chronic inhalation exposures to poorly soluble particulates (PSP) has been a controversial issue for more than three decades. In 1998, an ILSI (International Life Sciences) Working Group of health scientists was convened to address this issue of applicability of experimental study findings of lung neoplasms in rats for lifetime-exposed production workers to PSPs. A full consensus view was not reached by the Workshop participants, although it was generally acknowledged that the findings of lung tumors in rats following chronic inhalation, particle-overload PSP exposures occurred only in rats and no other tested species; and that there was an absence of lung cancers in PSP-exposed production workers. Since the publication of the ILSI Workshop report in 2000, there have been important new data published on the human relevance issue. A thorough and comprehensive review of the health effects literature on poorly soluble particles/lung overload was undertaken and published by an ECETOC (European Centre for Ecotoxicology and Toxicology of Chemicals) Task Force in 2013. One of the significant conclusions derived from that technical report was that the rat is unique amongst all species in developing lung tumors under chronic inhalation overload exposures to PSPs. Accordingly, the objective of this review is to provide important insights on the fundamental differences in pulmonary responses between experimentally-exposed rats, other experimental species and occupationally-exposed humans. Briefly, five central factors are described by the following issues. Focusing on these five interrelated/convergent factors clearly demonstrate an inappropriateness in concluding that the findings of lung tumors in rats exposed chronically to high concentrations of PSPs are accurate representations of the risks of lung cancer in PSP-exposed production workers. The most plausible conclusion that can be reached is that results from chronic particle-overload inhalation studies with PSPs in rats have no relevance for determining lung cancer risks in production workers exposed for a working lifetime to these poorly soluble particulate-types.
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Affiliation(s)
| | - R Kreiling
- Clariant Produkte (DE) GmbH, Sulzbach, Germany
| | - L S Levy
- Cranfield University, Cranfield, UK
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31
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Endoscope analysis on peristaltic blood flow of Sisko fluid with Titanium magneto-nanoparticles. Comput Biol Med 2016; 78:29-41. [DOI: 10.1016/j.compbiomed.2016.09.007] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 09/11/2016] [Accepted: 09/12/2016] [Indexed: 01/10/2023]
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32
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Development of linear and threshold no significant risk levels for inhalation exposure to titanium dioxide using systematic review and mode of action considerations. Regul Toxicol Pharmacol 2016; 80:60-70. [DOI: 10.1016/j.yrtph.2016.05.031] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 05/19/2016] [Accepted: 05/20/2016] [Indexed: 11/21/2022]
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Brundo MV, Pecoraro R, Marino F, Salvaggio A, Tibullo D, Saccone S, Bramanti V, Buccheri MA, Impellizzeri G, Scuderi V, Zimbone M, Privitera V. Toxicity Evaluation of New Engineered Nanomaterials in Zebrafish. Front Physiol 2016; 7:130. [PMID: 27148069 PMCID: PMC4829578 DOI: 10.3389/fphys.2016.00130] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Accepted: 03/24/2016] [Indexed: 11/24/2022] Open
Abstract
The effect of the nanoparticles on the marine organisms, depends on their size, chemical composition, surface structure, solubility and shape. In order to take advantage from their activity, preserving the surrounding environment from a possible pollution, we are trying to trap the nanoparticles into new nanomaterials. The nanomaterials tested were synthesized proposing a ground-breaking approach by an upside-down vision of the Au/TiO2 nano-system to avoid the release of nanoparticles. The system was synthesized by wrapping Au nanoparticles with a thin layer of TiO2. The non-toxicity of the nano-system was established by testing the effect of the material on zebrafish larvae. Danio rerio o zebrafish was considered an excellent model for the environmental biomonitoring of aquatic environments and the Zebrafish Embryo Toxicity Test (ZFET) is considered an alternative method of animal test. For this reason zebrafish larvae were exposed to different concentrations of nanoparticles of TiO2 and Au and new nanomaterials. As biomarkers of exposure, we evaluated the expression of metallothioneins by immunohistochemistry analysis and western blotting analysis also. The results obtained by toxicity test showed that neither mortality as well as sublethal effects were induced by the different nanomaterials and nanoparticles tested. Only zebrafish larvae exposed to free Au nanoparticles showed a different response to anti-MT antibody. In fact, the immunolocalization analysis highlighted an increase of the metallothioneins synthesis.
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Affiliation(s)
- Maria V. Brundo
- Department of Biological, Geological and Environmental Science, University of CataniaCatania, Italy
| | - Roberta Pecoraro
- Department of Biological, Geological and Environmental Science, University of CataniaCatania, Italy
| | - Fabio Marino
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Polo Universitario dell'AnnunziataMessina, Italy
| | | | - Daniele Tibullo
- Department of Biological, Geological and Environmental Science, University of CataniaCatania, Italy
| | - Salvatore Saccone
- Department of Biological, Geological and Environmental Science, University of CataniaCatania, Italy
| | - Vincenzo Bramanti
- Department of Biomedical and Biotechnology Sciences, University of CataniaCatania, Italy
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Pease C, Rücker T, Birk T. Review of the Evidence from Epidemiology, Toxicology, and Lung Bioavailability on the Carcinogenicity of Inhaled Iron Oxide Particulates. Chem Res Toxicol 2016; 29:237-54. [DOI: 10.1021/acs.chemrestox.5b00448] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Camilla Pease
- Ramboll ENVIRON
UK Limited, 1 Broad Gate, The Headrow, Leeds LS1 8EQ, U.K
| | - Thomas Rücker
- Ramboll ENVIRON
Germany GmbH, Aschauer Straße
32a, 81549 München, Germany
| | - Thomas Birk
- Ramboll ENVIRON
Germany GmbH, Friedrich-Ebert-Strasse
55, 45127 Essen, Germany
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35
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Sayers BC, Walker NJ, Roycroft JH, Germolec DR, Baker GL, Clark ML, Hayden BK, DeFord H, Dill JA, Gupta A, Stout MD. Lung deposition and clearance of microparticle and nanoparticle C60 fullerene aggregates in B6C3F1 mice and Wistar Han rats following nose-only inhalation for 13 weeks. Toxicology 2015; 339:87-96. [PMID: 26612504 DOI: 10.1016/j.tox.2015.11.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Revised: 11/10/2015] [Accepted: 11/11/2015] [Indexed: 11/25/2022]
Abstract
C60 fullerenes (C60) are spherical structures consisting of 60 carbon atoms that are generated via combustion from both natural and anthropogenic sources. C60 are also synthesized intentionally for industrial applications. Individual C60 structures have an approximate diameter of 1nm; however, C60 readily forms aggregates and typically exist as larger particles that range from nanometers to micrometers in diameter. In this report, lung and extrapulmonary tissue deposition and lung clearance of C60 nanoparticles (nano-C60, 50nm) and microparticles (micro-C60, 1μm) were examined in Wistar Han rats and B6C3F1/N mice after nose-only inhalation for 90 days. Exposure concentrations were 0.5 and 2mg/m(3) (nano-C60) and 2, 15, and 30mg/m(3) (micro-C60). For both C60 particle sizes, the C60 lung burden increased proportionally to exposure concentration. The C60 lung burden was greater in both species at all time points following exposure to nano-C60 particle exposure compared to micro-C60 exposure at the common exposure concentration 2mg/m(3). The calculated C60 particle lung retention half-times were similar for both nano-C60 and micro-C60 exposure at 2mg/m(3) in male mice (15-16 days). In contrast, in male rats, the half-time of C60 particles following nano-C60 exposure (61 days) was roughly twice as long as the half-time following micro-C60 exposure (27 days) at the same exposure concentration (2mg/m(3)) and was similar to the clearance following micro-C60 exposure at higher exposure concentrations (15 and 30mg/m(3)). C60 was detected in bronchial lymph nodes but the burden was not quantified due to the high variability in the data. C60 concentrations were below the experimental limit of quantitation (ELOQ) in liver, spleen, blood, brain and kidney tissues. These tissue burden data provide information for comparison between nanometer and micrometer sized C60 particle exposure and will aid in the interpretation of toxicity data.
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Affiliation(s)
- Brian C Sayers
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, 111 Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Nigel J Walker
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, 111 Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Joseph H Roycroft
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, 111 Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Dori R Germolec
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, 111 Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Gregory L Baker
- Battelle Toxicology Northwest, 900 Battelle Boulevard, Richland, WA 99354, USA
| | - Mark L Clark
- Battelle Toxicology Northwest, 900 Battelle Boulevard, Richland, WA 99354, USA
| | - Barry K Hayden
- Battelle Toxicology Northwest, 900 Battelle Boulevard, Richland, WA 99354, USA
| | - Henry DeFord
- Battelle Toxicology Northwest, 900 Battelle Boulevard, Richland, WA 99354, USA
| | - Jeffrey A Dill
- Battelle Toxicology Northwest, 900 Battelle Boulevard, Richland, WA 99354, USA
| | - Amit Gupta
- Battelle Toxicology Northwest, 900 Battelle Boulevard, Richland, WA 99354, USA
| | - Matthew D Stout
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, 111 Alexander Drive, Research Triangle Park, NC 27709, USA.
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Maser E, Schulz M, Sauer UG, Wiemann M, Ma-Hock L, Wohlleben W, Hartwig A, Landsiedel R. In vitro and in vivo genotoxicity investigations of differently sized amorphous SiO2 nanomaterials. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2015; 794:57-74. [DOI: 10.1016/j.mrgentox.2015.10.005] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Revised: 10/17/2015] [Accepted: 10/27/2015] [Indexed: 12/27/2022]
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37
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Risk assessment strategies for nanoscale and fine-sized titanium dioxide particles: Recognizing hazard and exposure issues. Food Chem Toxicol 2015; 85:138-47. [PMID: 26362081 DOI: 10.1016/j.fct.2015.07.001] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 06/29/2015] [Accepted: 07/01/2015] [Indexed: 11/20/2022]
Abstract
The basic tenets for assessing health risks posed by nanoparticles (NP) requires documentation of hazards and the corresponding exposures that may occur. Accordingly, this review describes the range and types of potential human exposures that may result from interactions with titanium dioxide (TiO2) particles or NP - either in the occupational/workplace environment, or in consumer products, including food materials and cosmetics. Each of those applications has a predominant route of exposure. Very little is known about the human impact potential from environmental exposures to NP - thus this particular issue will not be discussed further. In the workplace or occupational setting inhalation exposure predominates. Experimental toxicity studies demonstrate low hazards in particle-exposed rats. Only at chronic overload exposures do rats develop forms of lung pathology. These findings are not supported by multiple epidemiology studies in heavily-exposed TiO2 workers which demonstrate a lack of correlation between chronic particle exposures and adverse health outcomes including lung cancer and noncancerous chronic respiratory effects. Cosmetics and sunscreens represent the major application of dermal exposures to TiO2 particles. Experimental dermal studies indicate a lack of penetration of particles beyond the epidermis with no consequent health risks. Oral exposures to ingested TiO2 particles in food occur via passage through the gastrointestinal tract (GIT), with studies indicating negligible uptake of particles into the bloodstream of humans or rats with subsequent excretion through the feces. In addition, standardized guideline-mandated subchronic oral toxicity studies in rats demonstrate very low toxicity effects with NOAELs of >1000 mg/kg bw/day. Additional issues which are summarized in detail in this review are: 1) Methodologies for implementing the Nano Risk Framework - a process for ensuring the responsible development of products containing nanoscale materials; and 2) Safe-handling of nanomaterials in the laboratory.
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Stapleton PA, Nichols CE, Yi J, McBride CR, Minarchick VC, Shepherd DL, Hollander JM, Nurkiewicz TR. Microvascular and mitochondrial dysfunction in the female F1 generation after gestational TiO2 nanoparticle exposure. Nanotoxicology 2015; 9:941-51. [PMID: 25475392 DOI: 10.3109/17435390.2014.984251] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Due to the ongoing evolution of nanotechnology, there is a growing need to assess the toxicological outcomes in under-studied populations in order to properly consider the potential of engineered nanomaterials (ENM) and fully enhance their safety. Recently, we and others have explored the vascular consequences associated with gestational nanomaterial exposure, reporting microvascular dysfunction within the uterine circulation of pregnant dams and the tail artery of fetal pups. It has been proposed (via work derived by the Barker Hypothesis) that mitochondrial dysfunction and subsequent oxidative stress mechanisms as a possible link between a hostile gestational environment and adult disease. Therefore, in this study, we exposed pregnant Sprague-Dawley rats to nanosized titanium dioxide aerosols after implantation (gestational day 6). Pups were delivered, and the progeny grew into adulthood. Microvascular reactivity, mitochondrial respiration and hydrogen peroxide production of the coronary and uterine circulations of the female offspring were evaluated. While there were no significant differences within the maternal or litter characteristics, endothelium-dependent dilation and active mechanotransduction in both coronary and uterine arterioles were significantly impaired. In addition, there was a significant reduction in maximal mitochondrial respiration (state 3) in the left ventricle and uterus. These studies demonstrate microvascular dysfunction and coincide with mitochondrial inefficiencies in both the cardiac and uterine tissues, which may represent initial evidence that prenatal ENM exposure produces microvascular impairments that persist throughout multiple developmental stages.
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Affiliation(s)
- Phoebe A Stapleton
- a Center for Cardiovascular and Respiratory Sciences .,b Department of Physiology and Pharmacology , and
| | - Cody E Nichols
- a Center for Cardiovascular and Respiratory Sciences .,c Division of Exercise Physiology , West Virginia University School of Medicine , Morgantown , WV , USA
| | - Jinghai Yi
- a Center for Cardiovascular and Respiratory Sciences .,b Department of Physiology and Pharmacology , and
| | - Carroll R McBride
- a Center for Cardiovascular and Respiratory Sciences .,b Department of Physiology and Pharmacology , and
| | - Valerie C Minarchick
- a Center for Cardiovascular and Respiratory Sciences .,b Department of Physiology and Pharmacology , and
| | - Danielle L Shepherd
- a Center for Cardiovascular and Respiratory Sciences .,c Division of Exercise Physiology , West Virginia University School of Medicine , Morgantown , WV , USA
| | - John M Hollander
- a Center for Cardiovascular and Respiratory Sciences .,c Division of Exercise Physiology , West Virginia University School of Medicine , Morgantown , WV , USA
| | - Timothy R Nurkiewicz
- a Center for Cardiovascular and Respiratory Sciences .,b Department of Physiology and Pharmacology , and
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Fiume MM, Boyer I, Bergfeld WF, Belsito DV, Hill RA, Klaassen CD, Liebler DC, Marks JG, Shank RC, Slaga TJ, Snyder PW, Andersen FA. Safety Assessment of Talc as Used in Cosmetics. Int J Toxicol 2015; 34:66S-129S. [DOI: 10.1177/1091581815586797] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The Cosmetic Ingredient Review Expert Panel (Panel) assessed the safety of talc for use in cosmetics. The safety of talc has been the subject of much debate through the years, partly because the relationship between talc and asbestos is commonly misunderstood. Industry specifications state that cosmetic-grade talc must contain no detectable fibrous, asbestos minerals. Therefore, the large amount of available animal and clinical data the Panel relied on in assessing the safety of talc only included those studies on talc that did not contain asbestos. The Panel concluded that talc is safe for use in cosmetics in the present practices of use and concentration (some cosmetic products are entirely composed of talc). Talc should not be applied to the skin when the epidermal barrier is missing or significantly disrupted.
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Affiliation(s)
- Monice M. Fiume
- Cosmetic Ingredient Review Senior Scientific Analyst/Writer, Washington, DC, USA
| | - Ivan Boyer
- Cosmetic Ingredient Review Senior Toxicologist, Washington, DC, USA
| | | | | | - Ronald A. Hill
- Cosmetic Ingredient Review Expert Panel Member, Washington, DC, USA
| | | | | | - James G. Marks
- Cosmetic Ingredient Review Expert Panel Member, Washington, DC, USA
| | - Ronald C. Shank
- Cosmetic Ingredient Review Expert Panel Member, Washington, DC, USA
| | - Thomas J. Slaga
- Cosmetic Ingredient Review Expert Panel Member, Washington, DC, USA
| | - Paul W. Snyder
- Cosmetic Ingredient Review Expert Panel Member, Washington, DC, USA
| | - F. Alan Andersen
- Former Director, Cosmetic Ingredient Review, Washington, DC, USA
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Pothmann D, Simar S, Schuler D, Dony E, Gaering S, Le Net JL, Okazaki Y, Chabagno JM, Bessibes C, Beausoleil J, Nesslany F, Régnier JF. Lung inflammation and lack of genotoxicity in the comet and micronucleus assays of industrial multiwalled carbon nanotubes Graphistrength(©) C100 after a 90-day nose-only inhalation exposure of rats. Part Fibre Toxicol 2015; 12:21. [PMID: 26156627 PMCID: PMC4496819 DOI: 10.1186/s12989-015-0096-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 06/17/2015] [Indexed: 12/28/2022] Open
Abstract
Background Graphistrength© C100 multiwalled carbon nanotubes (MWCNT) provide superior electrical and mechanical properties for various applications. The evaluation of the intrinsic hazard properties of Graphistrength© C100 is an essential step for safe use. A general feature of multiwalled carbon nanotubes after inhalation or intratracheal exposures is the induction of an inflammatory reaction in the lungs sometimes associated with local genotoxic effects. Methods After investigating different parameters for the aerosol generation and performing a 5-day inhalation range finding study, male and female Wistar rats were exposed nose-only for 90 days to target concentrations of 0.05, 0.25 and 5.0 mg/m3 air of Graphistrength© C100 and sacrificed 24 h and 90 days after the last exposure. Broncho-alveolar lavage fluid (BALF) was also collected and analyzed for inflammatory parameters. Twenty-four hours post-exposure, chromosomal aberrations in the bone marrow cells were evaluated by the micronucleus test and DNA damages in the lung, kidney and liver cells by both the standard and the human 8-oxoguanine DNA N-glycosylase 1 (hOGG1)-modified comet assay. All studies were performed according to the OECD test guidelines. Results An inflammatory lung reaction and the release of inflammatory factors in the BALF were observed in all rats exposed to 5.0 mg/m3, associated with changes in the differential white blood cells counts. The slight changes in BALF parameters at 0.25 mg/m3 recovered and signs of lung clearance of the MWCNT were observed. No pathological changes were observed on the pleura. Neither increase in the number of micronucleated polychromatic erythrocytes nor increase in percent DNA damage were observed at any concentration. Conclusions Lung inflammation characteristic of an overload with insoluble particles was observed after a 90-day exposure to 5.0 mg/m3 of Graphistrength© C100. Clear signs of clearance and recovery were observed at 0.25 mg/m3. No genotoxicity was detected locally in lung and distally in bone marrow, liver and kidney. Therefore, Graphistrength© C100 appears of low concern in term of local and systemic genotoxicity and a No-Observed Adverse Effect Concentration (NOAEC) of 0.25 mg/m3 (0.28 mg/m3 as actual concentration) was established for the repeated-dose toxicity. Electronic supplementary material The online version of this article (doi:10.1186/s12989-015-0096-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Daniela Pothmann
- Harlan Laboratories Ltd, Zelgliweg 1, 4452, Itingen, Switzerland.
| | - Sophie Simar
- Laboratoire de Toxicologie Génétique, Institut Pasteur de Lille, 1 rue du Pr. Calmette, 59019, Lille, Cedex, France.
| | - Detlef Schuler
- Harlan Laboratories Ltd, Zelgliweg 1, 4452, Itingen, Switzerland.
| | - Eva Dony
- Harlan Cytotest Cell Research GmbH, In den Leppsteinwiesen 19, 64380, Rossdorf, Germany.
| | - Stéphane Gaering
- Harlan Laboratories Ltd, Zelgliweg 1, 4452, Itingen, Switzerland.
| | - Jean-Loïc Le Net
- Le Net Pathology Consulting, 18 rue Henry Dunant, 37400, Amboise, France.
| | - Yoshi Okazaki
- AnaPath GmbH, Buchsweg 56, 4625, Oberbuchsiten, Switzerland.
| | - Jean Michel Chabagno
- Arkema France, Groupement de Recherches de Lacq (GRL), Laboratoires d'analyse de surface et microscopie et de chimie analytique, 64170, Lacq, France.
| | - Cécile Bessibes
- Arkema France, Groupement de Recherches de Lacq (GRL), Laboratoires d'analyse de surface et microscopie et de chimie analytique, 64170, Lacq, France.
| | - Julien Beausoleil
- Arkema France, Groupement de Recherches de Lacq (GRL), Laboratoires d'analyse de surface et microscopie et de chimie analytique, 64170, Lacq, France.
| | - Fabrice Nesslany
- Laboratoire de Toxicologie Génétique, Institut Pasteur de Lille, 1 rue du Pr. Calmette, 59019, Lille, Cedex, France. .,UDSL, EA 4483, Département Toxicologie-Santé Publique-Environnement, Faculté de Pharmacie, 1 rue du Pr. Laguesse, 59019, Lille, France.
| | - Jean-François Régnier
- Arkema France, Département Toxicologie et Environnement, 420 rue d' Estienne d' Orves, 92705, Colombes, France.
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41
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Farsalinos KE, Voudris V, Poulas K. Are metals emitted from electronic cigarettes a reason for health concern? A risk-assessment analysis of currently available literature. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2015; 12:5215-32. [PMID: 25988311 PMCID: PMC4454963 DOI: 10.3390/ijerph120505215] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/21/2015] [Revised: 04/28/2015] [Accepted: 05/07/2015] [Indexed: 11/16/2022]
Abstract
BACKGROUND Studies have found that metals are emitted to the electronic cigarette (EC) aerosol. However, the potential health impact of exposure to such metals has not been adequately defined. The purpose of this study was to perform a risk assessment analysis, evaluating the exposure of electronic cigarette (EC) users to metal emissions based on findings from the published literature. METHODS Two studies were found in the literature, measuring metals emitted to the aerosol from 13 EC products. We estimated that users take on average 600 EC puffs per day, but we evaluated the daily exposure from 1200 puffs. Estimates of exposure were compared with the chronic Permissible Daily Exposure (PDE) from inhalational medications defined by the U.S. Pharmacopeia (cadmium, chromium, copper, lead and nickel), the Minimal Risk Level (MRL) defined by the Agency for Toxic Substances and Disease Registry (manganese) and the Recommended Exposure Limit (REL) defined by the National Institute of Occupational Safety and Health (aluminum, barium, iron, tin, titanium, zinc and zirconium). RESULTS The average daily exposure from 13 EC products was 2.6 to 387 times lower than the safety cut-off point of PDEs, 325 times lower than the safety limit of MRL and 665 to 77,514 times lower than the safety cut-off point of RELs. Only one of the 13 products was found to result in exposure 10% higher than PDE for one metal (cadmium) at the extreme daily use of 1200 puffs. Significant differences in emissions between products were observed. CONCLUSIONS Based on currently available data, overall exposure to metals from EC use is not expected to be of significant health concern for smokers switching to EC use, but is an unnecessary source of exposure for never-smokers. Metal analysis should be expanded to more products and exposure can be further reduced through improvements in product quality and appropriate choice of materials.
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Affiliation(s)
- Konstantinos E Farsalinos
- Department of Cardiology, Onassis Cardiac Surgery Center, Sygrou 356, Kallithea 17674, Greece.
- Department of Pharmacy, University of Patras, Rio 26500, Greece.
| | - Vassilis Voudris
- Department of Cardiology, Onassis Cardiac Surgery Center, Sygrou 356, Kallithea 17674, Greece.
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Abstract
Nucleic acids show immense potential to treat cancer, acquired immune deficiency syndrome, neurological diseases and other incurable human diseases. Upon systemic administration, they encounter a series of barriers and hence barely reach the site of action, the cell. Intracellular delivery of nucleic acids is facilitated by nanovectors, both viral and non-viral. A major advantage of non-viral vectors over viral vectors is safety. Nanovectors evaluated specifically for nucleic acid delivery include polyplexes, lipoplexes and other cationic carrier-based vectors. However, more recently there is an increased interest in inorganic nanovectors for nucleic acid delivery. Nevertheless, there is no comprehensive review on the subject. The present review would cover in detail specific properties and types of inorganic nanovectors, their preparation techniques and various biomedical applications as therapeutics, diagnostics and theranostics. Future prospects are also suggested.
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Borm P, Cassee FR, Oberdörster G. Lung particle overload: old school -new insights? Part Fibre Toxicol 2015; 12:10. [PMID: 25927223 PMCID: PMC4419487 DOI: 10.1186/s12989-015-0086-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 03/09/2015] [Indexed: 11/10/2022] Open
Affiliation(s)
- Paul Borm
- Zuyd Hogeschool, Department of Life Sciences & Health, PO Box 550, 6400, AN, Heerlen, The Netherlands.
| | - Flemming R Cassee
- National Institute for Public Health and the Environment (RIVM), PO Box 1, 3720, BA, Bilthoven, The Netherlands. .,Institute of Risk Assessment Sciences, Utrecht University, PO Box 80.163, 3508, TD, Utrecht, The Netherlands.
| | - Günter Oberdörster
- Professor Emeritus of Toxicology, University of Rochester, Department of Environmental Medicine, Rochester, NY, 14642, USA.
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Morfeld P, Bruch J, Levy L, Ngiewih Y, Chaudhuri I, Muranko HJ, Myerson R, McCunney RJ. Translational toxicology in setting occupational exposure limits for dusts and hazard classification - a critical evaluation of a recent approach to translate dust overload findings from rats to humans. Part Fibre Toxicol 2015; 12:3. [PMID: 25925672 PMCID: PMC4443602 DOI: 10.1186/s12989-015-0079-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 01/12/2015] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND We analyze the scientific basis and methodology used by the German MAK Commission in their recommendations for exposure limits and carcinogen classification of "granular biopersistent particles without known specific toxicity" (GBS). These recommendations are under review at the European Union level. We examine the scientific assumptions in an attempt to reproduce the results. MAK's human equivalent concentrations (HECs) are based on a particle mass and on a volumetric model in which results from rat inhalation studies are translated to derive occupational exposure limits (OELs) and a carcinogen classification. METHODS We followed the methods as proposed by the MAK Commission and Pauluhn 2011. We also examined key assumptions in the metrics, such as surface area of the human lung, deposition fractions of inhaled dusts, human clearance rates; and risk of lung cancer among workers, presumed to have some potential for lung overload, the physiological condition in rats associated with an increase in lung cancer risk. RESULTS The MAK recommendations on exposure limits for GBS have numerous incorrect assumptions that adversely affect the final results. The procedures to derive the respirable occupational exposure limit (OEL) could not be reproduced, a finding raising considerable scientific uncertainty about the reliability of the recommendations. Moreover, the scientific basis of using the rat model is confounded by the fact that rats and humans show different cellular responses to inhaled particles as demonstrated by bronchoalveolar lavage (BAL) studies in both species. CONCLUSION Classifying all GBS as carcinogenic to humans based on rat inhalation studies in which lung overload leads to chronic inflammation and cancer is inappropriate. Studies of workers, who have been exposed to relevant levels of dust, have not indicated an increase in lung cancer risk. Using the methods proposed by the MAK, we were unable to reproduce the OEL for GBS recommended by the Commission, but identified substantial errors in the models. Considerable shortcomings in the use of lung surface area, clearance rates, deposition fractions; as well as using the mass and volumetric metrics as opposed to the particle surface area metric limit the scientific reliability of the proposed GBS OEL and carcinogen classification.
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Affiliation(s)
- Peter Morfeld
- Institute for Occupational Epidemiology and Risk Assessment of Evonik Industries, AG Rellinghauser Straße 1-11, Essen, 45128, Germany.
- Institute and Policlinic for Occupational Medicine, Environmental Medicine and Preventive Research, University of Cologne, Cologne, Germany.
| | - Joachim Bruch
- University Duisburg-Essen, Medical Faculty, Essen, Germany.
- IBE GmbH, Cologne, Germany.
| | - Len Levy
- Cranfield University, ᅟ, Cranfield, UK.
| | | | | | | | - Ross Myerson
- Department of Occupational Health, MedStar Washington Hospital Center, Washington, DC, USA.
- The George Washington University School of Public Health, Washington, DC, USA.
| | - Robert J McCunney
- Massachusetts Institute of Technology, Cambridge, MA, USA.
- Brigham and Women's Hospital, Boston, MA, USA.
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Armstead AL, Minarchick VC, Porter DW, Nurkiewicz TR, Li B. Acute inflammatory responses of nanoparticles in an intra-tracheal instillation rat model. PLoS One 2015; 10:e0118778. [PMID: 25738830 PMCID: PMC4349695 DOI: 10.1371/journal.pone.0118778] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 01/22/2015] [Indexed: 12/30/2022] Open
Abstract
Exposure to hard metal tungsten carbide cobalt (WC-Co) "dusts" in enclosed industrial environments is known to contribute to the development of hard metal lung disease and an increased risk for lung cancer. Currently, the influence of local and systemic inflammation on disease progression following WC-Co exposure remains unclear. To better understand the relationship between WC-Co nanoparticle (NP) exposure and its resultant effects, the acute local pulmonary and systemic inflammatory responses caused by WC-Co NPs were explored using an intra-tracheal instillation (IT) model and compared to those of CeO2 (another occupational hazard) NP exposure. Sprague-Dawley rats were given an IT dose (0-500 μg per rat) of WC-Co or CeO2 NPs. Following 24-hr exposure, broncho-alveolar lavage fluid and whole blood were collected and analyzed. A consistent lack of acute local pulmonary inflammation was observed in terms of the broncho-alveolar lavage fluid parameters examined (i.e. LDH, albumin, and macrophage activation) in animals exposed to WC-Co NP; however, significant acute pulmonary inflammation was observed in the CeO2 NP group. The lack of acute inflammation following WC-Co NP exposure contrasts with earlier in vivo reports regarding WC-Co toxicity in rats, illuminating the critical role of NP dose and exposure time and bringing into question the potential role of impurities in particle samples. Further, we demonstrated that WC-Co NP exposure does not induce acute systemic effects since no significant increase in circulating inflammatory cytokines were observed. Taken together, the results of this in vivo study illustrate the distinct differences in acute local pulmonary and systemic inflammatory responses to NPs composed of WC-Co and CeO2; therefore, it is important that the outcomes of pulmonary exposure to one type of NPs may not be implicitly extrapolated to other types of NPs.
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Affiliation(s)
- Andrea L. Armstead
- Biomaterials, Bioengineering & Nanotechnology Laboratory, Department of Orthopaedics, School of Medicine, West Virginia University, Morgantown, West Virginia, United States of America
- Pharmaceutical and Pharmacological Sciences Graduate Program, School of Pharmacy, West Virginia University, Morgantown, West Virginia, United States of America
| | - Valerie C. Minarchick
- Department of Physiology and Pharmacology, School of Medicine, West Virginia University, Morgantown, West Virginia, United States of America
- Center for Cardiovascular and Respiratory Sciences, Robert C. Byrd Health Sciences Center, School of Medicine, West Virginia University, Morgantown, West Virginia, United States of America
| | - Dale W. Porter
- Department of Physiology and Pharmacology, School of Medicine, West Virginia University, Morgantown, West Virginia, United States of America
- Pathology and Physiology Research Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, West Virginia, United States of America
| | - Timothy R. Nurkiewicz
- Department of Physiology and Pharmacology, School of Medicine, West Virginia University, Morgantown, West Virginia, United States of America
- Center for Cardiovascular and Respiratory Sciences, Robert C. Byrd Health Sciences Center, School of Medicine, West Virginia University, Morgantown, West Virginia, United States of America
- Pathology and Physiology Research Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, West Virginia, United States of America
| | - Bingyun Li
- Biomaterials, Bioengineering & Nanotechnology Laboratory, Department of Orthopaedics, School of Medicine, West Virginia University, Morgantown, West Virginia, United States of America
- Pharmaceutical and Pharmacological Sciences Graduate Program, School of Pharmacy, West Virginia University, Morgantown, West Virginia, United States of America
- Pathology and Physiology Research Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, West Virginia, United States of America
- Mary Babb Randolph Cancer Center, Morgantown, West Virginia, United States of America
- * E-mail:
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Halappanavar S, Saber AT, Decan N, Jensen KA, Wu D, Jacobsen NR, Guo C, Rogowski J, Koponen IK, Levin M, Madsen AM, Atluri R, Snitka V, Birkedal RK, Rickerby D, Williams A, Wallin H, Yauk CL, Vogel U. Transcriptional profiling identifies physicochemical properties of nanomaterials that are determinants of the in vivo pulmonary response. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2015; 56:245-64. [PMID: 25504612 DOI: 10.1002/em.21936] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2014] [Revised: 11/19/2014] [Accepted: 11/21/2014] [Indexed: 05/28/2023]
Abstract
We applied transcriptional profiling to elucidate the mechanisms associated with pulmonary responses to titanium dioxide (TiO2 ) nanoparticles (NPs) of different sizes and surface coatings, and to determine if these responses are modified by NP size, surface area, surface modification, and embedding in paint matrices. Adult C57BL/6 mice were exposed via single intratracheal instillations to free forms of TiO2 NPs (10, 20.6, or 38 nm in diameter) with different surface coatings, or TiO2 NPs embedded in paint matrices. Controls were exposed to dispersion medium devoid of NPs. TiO2 NPs were characterized for size, surface area, chemical impurities, and agglomeration state in the exposure medium. Pulmonary transcriptional profiles were generated using microarrays from tissues collected one and 28 d postexposure. Property-specific pathway effects were identified. Pulmonary protein levels of specific inflammatory cytokines and chemokines were confirmed by ELISA. The data were collapsed to 659 differentially expressed genes (P ≤ 0.05; fold change ≥ 1.5). Unsupervised hierarchical clustering of these genes revealed that TiO2 NPs clustered mainly by postexposure timepoint followed by particle type. A pathway-based meta-analysis showed that the combination of smaller size, large deposited surface area, and surface amidation contributes to TiO2 NP gene expression response. Embedding of TiO2 NP in paint dampens the overall transcriptional effects. The magnitude of the expression changes associated with pulmonary inflammation differed across all particles; however, the underlying pathway perturbations leading to inflammation were similar, suggesting a generalized mechanism-of-action for all TiO2 NPs. Thus, transcriptional profiling is an effective tool to determine the property-specific biological/toxicity responses induced by nanomaterials.
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Affiliation(s)
- Sabina Halappanavar
- Environmental Health Science and Research Bureau, Health Canada, Ottawa, Canada
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Oberdörster G, Castranova V, Asgharian B, Sayre P. Inhalation Exposure to Carbon Nanotubes (CNT) and Carbon Nanofibers (CNF): Methodology and Dosimetry. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2015; 18:121-212. [PMID: 26361791 PMCID: PMC4706753 DOI: 10.1080/10937404.2015.1051611] [Citation(s) in RCA: 98] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Carbon nanotubes (CNT) and nanofibers (CNF) are used increasingly in a broad array of commercial products. Given current understandings, the most significant life-cycle exposures to CNT/CNF occur from inhalation when they become airborne at different stages of their life cycle, including workplace, use, and disposal. Increasing awareness of the importance of physicochemical properties as determinants of toxicity of CNT/CNF and existing difficulties in interpreting results of mostly acute rodent inhalation studies to date necessitate a reexamination of standardized inhalation testing guidelines. The current literature on pulmonary exposure to CNT/CNF and associated effects is summarized; recommendations and conclusions are provided that address test guideline modifications for rodent inhalation studies that will improve dosimetric extrapolation modeling for hazard and risk characterization based on the analysis of exposure-dose-response relationships. Several physicochemical parameters for CNT/CNF, including shape, state of agglomeration/aggregation, surface properties, impurities, and density, influence toxicity. This requires an evaluation of the correlation between structure and pulmonary responses. Inhalation, using whole-body exposures of rodents, is recommended for acute to chronic pulmonary exposure studies. Dry powder generator methods for producing CNT/CNF aerosols are preferred, and specific instrumentation to measure mass, particle size and number distribution, and morphology in the exposure chambers are identified. Methods are discussed for establishing experimental exposure concentrations that correlate with realistic human exposures, such that unrealistically high experimental concentrations need to be identified that induce effects under mechanisms that are not relevant for workplace exposures. Recommendations for anchoring data to results seen for positive and negative benchmark materials are included, as well as periods for postexposure observation. A minimum data set of specific bronchoalveolar lavage parameters is recommended. Retained lung burden data need to be gathered such that exposure-dose-response correlations may be analyzed and potency comparisons between materials and mammalian species are obtained considering dose metric parameters for interpretation of results. Finally, a list of research needs is presented to fill data gaps for further improving design, analysis, and interpretation and extrapolation of results of rodent inhalation studies to refine meaningful risk assessments for humans.
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Affiliation(s)
- Günter Oberdörster
- Department of Environmental Medicine, University of Rochester, Rochester, New York, USA
| | - Vincent Castranova
- Formerly with the National Institute for Occupational Safety and Health, West Virginia University School of Pharmacy, Morgantown, West Virginia, USA
| | | | - Phil Sayre
- Formerly with the U.S. Environmental Protection Agency, Washington, DC, USA
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Savi M, Rossi S, Bocchi L, Gennaccaro L, Cacciani F, Perotti A, Amidani D, Alinovi R, Goldoni M, Aliatis I, Lottici PP, Bersani D, Campanini M, Pinelli S, Petyx M, Frati C, Gervasi A, Urbanek K, Quaini F, Buschini A, Stilli D, Rivetti C, Macchi E, Mutti A, Miragoli M, Zaniboni M. Titanium dioxide nanoparticles promote arrhythmias via a direct interaction with rat cardiac tissue. Part Fibre Toxicol 2014; 11:63. [PMID: 25487314 PMCID: PMC4349471 DOI: 10.1186/s12989-014-0063-3] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 11/06/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In light of recent developments in nanotechnologies, interest is growing to better comprehend the interaction of nanoparticles with body tissues, in particular within the cardiovascular system. Attention has recently focused on the link between environmental pollution and cardiovascular diseases. Nanoparticles <50 nm in size are known to pass the alveolar-pulmonary barrier, enter into bloodstream and induce inflammation, but the direct pathogenic mechanisms still need to be evaluated. We thus focused our attention on titanium dioxide (TiO₂) nanoparticles, the most diffuse nanomaterial in polluted environments and one generally considered inert for the human body. METHODS We conducted functional studies on isolated adult rat cardiomyocytes exposed acutely in vitro to TiO₂ and on healthy rats administered a single dose of 2 mg/Kg TiO₂ NPs via the trachea. Transmission electron microscopy was used to verify the actual presence of TiO₂ nanoparticles within cardiac tissue, toxicological assays were used to assess lipid peroxidation and DNA tissue damage, and an in silico method was used to model the effect on action potential. RESULTS Ventricular myocytes exposed in vitro to TiO₂ had significantly reduced action potential duration, impairment of sarcomere shortening and decreased stability of resting membrane potential. In vivo, a single intra-tracheal administration of saline solution containing TiO₂ nanoparticles increased cardiac conduction velocity and tissue excitability, resulting in an enhanced propensity for inducible arrhythmias. Computational modeling of ventricular action potential indicated that a membrane leakage could account for the nanoparticle-induced effects measured on real cardiomyocytes. CONCLUSIONS Acute exposure to TiO₂ nanoparticles acutely alters cardiac excitability and increases the likelihood of arrhythmic events.
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Affiliation(s)
- Monia Savi
- Department of Life Sciences, University of Parma, Parma, Italy. .,CERT, Center of Excellence for Toxicological Research, Department of Clinical and Experimental Medicine, Via Gramsci 14, Parma, 43126, Italy.
| | - Stefano Rossi
- Department of Life Sciences, University of Parma, Parma, Italy. .,CERT, Center of Excellence for Toxicological Research, Department of Clinical and Experimental Medicine, Via Gramsci 14, Parma, 43126, Italy.
| | - Leonardo Bocchi
- Department of Life Sciences, University of Parma, Parma, Italy.
| | | | | | - Alessio Perotti
- Department of Life Sciences, University of Parma, Parma, Italy.
| | - Davide Amidani
- Department of Life Sciences, University of Parma, Parma, Italy.
| | - Rossella Alinovi
- Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy. .,CERT, Center of Excellence for Toxicological Research, Department of Clinical and Experimental Medicine, Via Gramsci 14, Parma, 43126, Italy.
| | - Matteo Goldoni
- Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy. .,CERT, Center of Excellence for Toxicological Research, Department of Clinical and Experimental Medicine, Via Gramsci 14, Parma, 43126, Italy.
| | - Irene Aliatis
- Department of Physics and Earth Science, University of Parma, Parma, Italy.
| | - Pier Paolo Lottici
- Department of Physics and Earth Science, University of Parma, Parma, Italy.
| | - Danilo Bersani
- Department of Physics and Earth Science, University of Parma, Parma, Italy.
| | | | - Silvana Pinelli
- Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy. .,CERT, Center of Excellence for Toxicological Research, Department of Clinical and Experimental Medicine, Via Gramsci 14, Parma, 43126, Italy.
| | - Marta Petyx
- Italian Worker Compensation Authority INAIL, ex-ISPESL Monteporzio Catone, Roma, Italy.
| | - Caterina Frati
- Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy.
| | - Andrea Gervasi
- Department of Biomedical, Biotechnological and Translational Sciences (S.Bi.Bi.T), University of Parma, Parma, Italy.
| | - Konrad Urbanek
- Department of Pharmacology, Second University of Naples, Naples, Italy.
| | - Federico Quaini
- Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy.
| | | | | | - Claudio Rivetti
- Department of Life Sciences, University of Parma, Parma, Italy.
| | - Emilio Macchi
- Department of Life Sciences, University of Parma, Parma, Italy. .,CERT, Center of Excellence for Toxicological Research, Department of Clinical and Experimental Medicine, Via Gramsci 14, Parma, 43126, Italy.
| | - Antonio Mutti
- Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy. .,CERT, Center of Excellence for Toxicological Research, Department of Clinical and Experimental Medicine, Via Gramsci 14, Parma, 43126, Italy.
| | - Michele Miragoli
- CERT, Center of Excellence for Toxicological Research, Department of Clinical and Experimental Medicine, Via Gramsci 14, Parma, 43126, Italy. .,Humanitas Clinical and Research Center, Via Manzoni 56, Rozzano, Milan, 20090, Italy.
| | - Massimiliano Zaniboni
- Department of Life Sciences, University of Parma, Parma, Italy. .,CERT, Center of Excellence for Toxicological Research, Department of Clinical and Experimental Medicine, Via Gramsci 14, Parma, 43126, Italy.
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Keller J, Wohlleben W, Ma-Hock L, Strauss V, Gröters S, Küttler K, Wiench K, Herden C, Oberdörster G, van Ravenzwaay B, Landsiedel R. Time course of lung retention and toxicity of inhaled particles: short-term exposure to nano-Ceria. Arch Toxicol 2014; 88:2033-59. [PMID: 25273020 PMCID: PMC4555363 DOI: 10.1007/s00204-014-1349-9] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Accepted: 08/25/2014] [Indexed: 11/30/2022]
Abstract
Two Ceria nanomaterials (NM-211 and NM-212) were tested for inhalation toxicity and organ burdens in order to design a chronic and carcinogenicity inhalation study (OECD TG No. 453). Rats inhaled aerosol concentrations of 0.5, 5, and 25 mg/m3 by whole-body exposure for 6 h/day on 5 consecutive days for 1 or 4 weeks with a post-exposure period of 24 or 129 days, respectively. Lungs were examined by bronchoalveolar lavage and histopathology. Inhaled Ceria is deposited in the lung and cleared with a half-time of 40 days; at aerosol concentrations higher than 0.5 mg/m3, this clearance was impaired resulting in a half-time above 200 days (25 mg/m3). After 5 days, Ceria (>0.5 mg/m3) induced an early inflammatory reaction by increases of neutrophils in the lung which decreased with time, with sustained exposure, and also after the exposure was terminated (during the post-exposure period). The neutrophil number observed in bronchoalveolar lavage fluid (BALF) was decreasing and supplemented by mononuclear cells, especially macrophages which were visible in histopathology but not in BALF. Further progression to granulomatous inflammation was observed 4 weeks post-exposure. The surface area of the particles provided a dose metrics with the best correlation of the two Ceria’s inflammatory responses; hence, the inflammation appears to be directed by the particle surface rather than mass or volume in the lung. Observing the time course of lung burden and inflammation, it appears that the dose rate of particle deposition drove an initial inflammatory reaction by neutrophils. The later phase (after 4 weeks) was dominated by mononuclear cells, especially macrophages. The progression toward the subsequent granulomatous reaction was driven by the duration and amount of the particles in the lung. The further progression of the biological response will be determined in the ongoing long-term study.
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Affiliation(s)
- Jana Keller
- Experimental Toxicology and Ecology, BASF SE, 67056, Ludwigshafen am Rhein, Germany
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Semmler-Behnke M, Lipka J, Wenk A, Hirn S, Schäffler M, Tian F, Schmid G, Oberdörster G, Kreyling WG. Size dependent translocation and fetal accumulation of gold nanoparticles from maternal blood in the rat. Part Fibre Toxicol 2014; 11:33. [PMID: 25928666 PMCID: PMC4445676 DOI: 10.1186/s12989-014-0033-9] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Accepted: 07/16/2014] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND There is evidence that nanoparticles (NP) cross epithelial and endothelial body barriers. We hypothesized that gold (Au) NP, once in the blood circulation of pregnant rats, will cross the placental barrier during pregnancy size-dependently and accumulate in the fetal organism by 1. transcellular transport across the hemochorial placenta, 2. transcellular transport across amniotic membranes 3. transport through ~20 nm wide transtrophoblastic channels in a size dependent manner. The three AuNP sizes used to test this hypothesis are either well below, or of similar size or well above the diameters of the transtrophoblastic channels. METHODS We intravenously injected monodisperse, negatively charged, radio-labelled 1.4 nm, 18 nm and 80 nm ¹⁹⁸AuNP at a mass dose of 5, 3 and 27 μg/rat, respectively, into pregnant rats on day 18 of gestation and in non-pregnant control rats and studied the biodistribution in a quantitative manner based on the radio-analysis of the stably labelled ¹⁹⁸AuNP after 24 hours. RESULTS We observed significant biokinetic differences between pregnant and non-pregnant rats. AuNP fractions in the uterus of pregnant rats were at least one order of magnitude higher for each particle size roughly proportional to the enlarged size and weight of the pregnant uterus. All three sizes of ¹⁹⁸AuNP were found in the placentas and amniotic fluids with 1.4 nm AuNP fractions being two orders of magnitude higher than those of the larger AuNP on a mass base. In the fetuses, only fractions of 0.0006 (30 ng) and 0.00004 (0.1 ng) of 1.4 nm and 18 nm AuNP, respectively, were detected, but no 80 nm AuNP (<0.000004 (<0.1 ng)). These data show that no AuNP entered the fetuses from amniotic fluids within 24 hours but indicate that AuNP translocation occurs across the placental tissues either through transtrophoblastic channels and/or via transcellular processes. CONCLUSION Our data suggest that the translocation of AuNP from maternal blood into the fetus is NP-size dependent which is due to mechanisms involving (1) transport through transtrophoblastic channels - also present in the human placenta - and/or (2) endocytotic and diffusive processes across the placental barrier.
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Affiliation(s)
- Manuela Semmler-Behnke
- Institute of Lung Biology and Disease, Helmholtz Zentrum München - German Research Center for Environmental Health, 85764, Neuherberg/Munich, Germany.
- Current address: Bavarian Health and Food Safety Authority, 85764, Oberschleissheim, Germany.
| | - Jens Lipka
- Institute of Lung Biology and Disease, Helmholtz Zentrum München - German Research Center for Environmental Health, 85764, Neuherberg/Munich, Germany.
| | - Alexander Wenk
- Institute of Lung Biology and Disease, Helmholtz Zentrum München - German Research Center for Environmental Health, 85764, Neuherberg/Munich, Germany.
| | - Stephanie Hirn
- Institute of Lung Biology and Disease, Helmholtz Zentrum München - German Research Center for Environmental Health, 85764, Neuherberg/Munich, Germany.
- Current address: Walter Brendel Centre of Experimental Medicine, Ludwig-Maximilians-Universität München, Munich, Germany.
| | - Martin Schäffler
- Institute of Lung Biology and Disease, Helmholtz Zentrum München - German Research Center for Environmental Health, 85764, Neuherberg/Munich, Germany.
| | - Furong Tian
- Institute of Lung Biology and Disease, Helmholtz Zentrum München - German Research Center for Environmental Health, 85764, Neuherberg/Munich, Germany.
- Current address: Focus Research Institute, Dublin Institute of Technology, Dublin, Ireland.
| | - Günter Schmid
- Institute of Inorganic Chemistry University Duisburg-Essen, 45117, Essen, Germany.
| | - Günter Oberdörster
- Department of Environmental Medicine, University of Rochester, Rochester, New York, USA.
| | - Wolfgang G Kreyling
- Institute of Lung Biology and Disease, Helmholtz Zentrum München - German Research Center for Environmental Health, 85764, Neuherberg/Munich, Germany.
- Institute of Epidemiology II, Helmholtz Zentrum München - German Research Center for Environmental Health, 85764, Neuherberg/Munich, Germany.
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