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Santibáñez-Andrade M, Quezada-Maldonado EM, Rivera-Pineda A, Chirino YI, García-Cuellar CM, Sánchez-Pérez Y. The Road to Malignant Cell Transformation after Particulate Matter Exposure: From Oxidative Stress to Genotoxicity. Int J Mol Sci 2023; 24:ijms24021782. [PMID: 36675297 PMCID: PMC9860989 DOI: 10.3390/ijms24021782] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 12/31/2022] [Accepted: 01/06/2023] [Indexed: 01/17/2023] Open
Abstract
In cells, oxidative stress is an imbalance between the production/accumulation of oxidants and the ability of the antioxidant system to detoxify these reactive products. Reactive oxygen species (ROS), cause multiple cellular damages through their interaction with biomolecules such as lipids, proteins, and DNA. Genotoxic damage caused by oxidative stress has become relevant since it can lead to mutation and play a central role in malignant transformation. The evidence describes chronic oxidative stress as an important factor implicated in all stages of the multistep carcinogenic process: initiation, promotion, and progression. In recent years, ambient air pollution by particulate matter (PM) has been cataloged as a cancer risk factor, increasing the incidence of different types of tumors. Epidemiological and toxicological evidence shows how PM-induced oxidative stress could mediate multiple events oriented to carcinogenesis, such as proliferative signaling, evasion of growth suppressors, resistance to cell death, induction of angiogenesis, and activation of invasion/metastasis pathways. In this review, we summarize the findings regarding the involvement of oxidative and genotoxic mechanisms generated by PM in malignant cell transformation. We also discuss the importance of new approaches oriented to studying the development of tumors associated with PM with more accuracy, pursuing the goal of weighing the impact of oxidative stress and genotoxicity as one of the main mechanisms associated with its carcinogenic potential.
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Affiliation(s)
- Miguel Santibáñez-Andrade
- Subdirección de Investigación Básica, Instituto Nacional de Cancerología, San Fernando No. 22, Tlalpan, México City CP 14080, Mexico
| | - Ericka Marel Quezada-Maldonado
- Subdirección de Investigación Básica, Instituto Nacional de Cancerología, San Fernando No. 22, Tlalpan, México City CP 14080, Mexico
| | - Andrea Rivera-Pineda
- Subdirección de Investigación Básica, Instituto Nacional de Cancerología, San Fernando No. 22, Tlalpan, México City CP 14080, Mexico
- Departamento de Biología Celular, Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV), Av. IPN No. 2508 Col. San Pedro Zacatenco, México City CP 07360, Mexico
| | - Yolanda I. Chirino
- Unidad de Biomedicina, Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Los Reyes Iztacala, Tlalnepantla CP 54090, Mexico
| | - Claudia M. García-Cuellar
- Subdirección de Investigación Básica, Instituto Nacional de Cancerología, San Fernando No. 22, Tlalpan, México City CP 14080, Mexico
- Correspondence: (C.M.G.-C.); (Y.S.-P.); Tel.: +52-(55)-3693-5200 (ext. 209) (Y.S.-P.)
| | - Yesennia Sánchez-Pérez
- Subdirección de Investigación Básica, Instituto Nacional de Cancerología, San Fernando No. 22, Tlalpan, México City CP 14080, Mexico
- Correspondence: (C.M.G.-C.); (Y.S.-P.); Tel.: +52-(55)-3693-5200 (ext. 209) (Y.S.-P.)
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Canivet L, Denayer FO, Dubot P, Garçon G, Lo Guidice JM. Toxicity of iron nanoparticles towards primary cultures of human bronchial epithelial cells. J Appl Toxicol 2020; 41:203-215. [PMID: 32767597 DOI: 10.1002/jat.4033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/26/2020] [Accepted: 05/26/2020] [Indexed: 11/08/2022]
Abstract
Air pollution is a public health issue and the toxicity of ambient particulate matter (PM) is well-recognized. Although it does not mostly contribute to the total mass of PM, increasing evidence indicates that the ultrafine fraction has generally a greater toxicity than the others do. A better knowledge of the underlying mechanisms involved in the pathological disorders related to nanoparticles (NPs) remains essential. Hence, the goal of this study was to determine better whether the exposure to a relatively low dose of well-characterized iron-rich NPs (Fe-NPs) might alter some critical toxicological endpoints in a relevant primary culture model of human bronchial epithelial cells (HBECs). We sought to use Fe-NPs representative of those frequently found in the industrial smokes of metallurgical industries. After having noticed the effective internalization of Fe-NPs, oxidative, inflammatory, DNA repair, and apoptotic endpoints were investigated within HBECs, mainly through transcriptional screening. Taken together, these results revealed that, despite it only produced relatively low levels of reactive oxygen species without any significant oxidative damage, low-dose Fe-NPs quickly significantly deregulated the transcription of some target genes closely involved in the proinflammatory response. Although this inflammatory process seemed to stay under control over time in case of this acute scenario of exposure, the future study of its evolution after a scenario of repeated exposure could be very interesting to evaluate the toxicity of Fe-NPs better.
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Affiliation(s)
- Ludivine Canivet
- Univ. Lille, CHU Lille, Institut Pasteur de Lille, ULR 4483-IMPECS-IMPact de l'Environnement Chimique sur la Santé, F-59000 Lille, France
| | - Franck-Olivier Denayer
- Univ. Lille, CHU Lille, Institut Pasteur de Lille, ULR 4483-IMPECS-IMPact de l'Environnement Chimique sur la Santé, F-59000 Lille, France
| | - Pierre Dubot
- CNRS UMR 7182, Métaux et céramiques à microstructure contrôlée, Institut de Chimie et des Matériaux, Paris Est, Thiais, France
| | - Guillaume Garçon
- Univ. Lille, CHU Lille, Institut Pasteur de Lille, ULR 4483-IMPECS-IMPact de l'Environnement Chimique sur la Santé, F-59000 Lille, France
| | - J-M Lo Guidice
- Univ. Lille, CHU Lille, Institut Pasteur de Lille, ULR 4483-IMPECS-IMPact de l'Environnement Chimique sur la Santé, F-59000 Lille, France
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Santibáñez-Andrade M, Chirino YI, González-Ramírez I, Sánchez-Pérez Y, García-Cuellar CM. Deciphering the Code between Air Pollution and Disease: The Effect of Particulate Matter on Cancer Hallmarks. Int J Mol Sci 2019; 21:ijms21010136. [PMID: 31878205 PMCID: PMC6982149 DOI: 10.3390/ijms21010136] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 12/19/2019] [Accepted: 12/20/2019] [Indexed: 12/12/2022] Open
Abstract
Air pollution has been recognized as a global health problem, causing around 7 million deaths worldwide and representing one of the highest environmental crises that we are now facing. Close to 30% of new lung cancer cases are associated with air pollution, and the impact is more evident in major cities. In this review, we summarize and discuss the evidence regarding the effect of particulate matter (PM) and its impact in carcinogenesis, considering the “hallmarks of cancer” described by Hanahan and Weinberg in 2000 and 2011 as a guide to describing the findings that support the impact of particulate matter during the cancer continuum.
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Affiliation(s)
- Miguel Santibáñez-Andrade
- Subdirección de Investigación Básica, Instituto Nacional de Cancerología, San Fernando No. 22, Tlalpan, México CP 14080, DF, Mexico; (M.S.-A.); (I.G.-R.)
| | - Yolanda I. Chirino
- Unidad de Biomedicina, Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Los Reyes Iztacala, Tlalnepantla CP 54090, Estado de México, Mexico;
| | - Imelda González-Ramírez
- Subdirección de Investigación Básica, Instituto Nacional de Cancerología, San Fernando No. 22, Tlalpan, México CP 14080, DF, Mexico; (M.S.-A.); (I.G.-R.)
| | - Yesennia Sánchez-Pérez
- Subdirección de Investigación Básica, Instituto Nacional de Cancerología, San Fernando No. 22, Tlalpan, México CP 14080, DF, Mexico; (M.S.-A.); (I.G.-R.)
- Correspondence: (Y.S.-P.); (C.M.G.-C.); Tel.: +52-(55)-3693-5200 (Y.S.-P. & C.M.G.-C.)
| | - Claudia M. García-Cuellar
- Subdirección de Investigación Básica, Instituto Nacional de Cancerología, San Fernando No. 22, Tlalpan, México CP 14080, DF, Mexico; (M.S.-A.); (I.G.-R.)
- Correspondence: (Y.S.-P.); (C.M.G.-C.); Tel.: +52-(55)-3693-5200 (Y.S.-P. & C.M.G.-C.)
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Zhang S, Wu H, Li S, Wang M, Fang L, Liu R. Melatonin Enhances Autophagy and Decreases Apoptosis Induced by nanosilica in RAW264.7 cells. IUBMB Life 2019; 71:1021-1029. [PMID: 31018046 DOI: 10.1002/iub.2055] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 04/09/2019] [Accepted: 04/10/2019] [Indexed: 12/13/2022]
Affiliation(s)
- Shi‐Hai Zhang
- Department of PulmonaryAnhui Geriatric Institute, the First Affiliated Hospital of Anhui Medical University Hefei China
- Anhui Provincial Children's HospitalChildren's Hospital of Anhui Medical University Hefei China
| | - Hui‐Mei Wu
- Department of PulmonaryAnhui Geriatric Institute, the First Affiliated Hospital of Anhui Medical University Hefei China
| | - Shuai Li
- Department of PulmonaryAnhui Geriatric Institute, the First Affiliated Hospital of Anhui Medical University Hefei China
| | - Mu‐Zi Wang
- Department of PulmonaryAnhui Geriatric Institute, the First Affiliated Hospital of Anhui Medical University Hefei China
| | - Lei Fang
- Department of PulmonaryAnhui Geriatric Institute, the First Affiliated Hospital of Anhui Medical University Hefei China
| | - Rong‐Yu Liu
- Department of PulmonaryAnhui Geriatric Institute, the First Affiliated Hospital of Anhui Medical University Hefei China
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Niranjan R, Thakur AK. The Toxicological Mechanisms of Environmental Soot (Black Carbon) and Carbon Black: Focus on Oxidative Stress and Inflammatory Pathways. Front Immunol 2017; 8:763. [PMID: 28713383 PMCID: PMC5492873 DOI: 10.3389/fimmu.2017.00763] [Citation(s) in RCA: 125] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 06/16/2017] [Indexed: 12/29/2022] Open
Abstract
The environmental soot and carbon blacks (CBs) cause many diseases in humans, but their underlying mechanisms of toxicity are still poorly understood. Both are formed after the incomplete combustion of hydrocarbons but differ in their constituents and percent carbon contents. For the first time, “Sir Percival Pott” described soot as a carcinogen, which was subsequently confirmed by many others. The existing data suggest three main types of diseases due to soot and CB exposures: cancer, respiratory diseases, and cardiovascular dysfunctions. Experimental models revealed the involvement of oxidative stress, DNA methylation, formation of DNA adducts, and Aryl hydrocarbon receptor activation as the key mechanisms of soot- and CB-induced cancers. Metals including Si, Fe, Mn, Ti, and Co in soot also contribute in the reactive oxygen species (ROS)-mediated DNA damage. Mechanistically, ROS-induced DNA damage is further enhanced by eosinophils and neutrophils via halide (Cl− and Br−) dependent DNA adducts formation. The activation of pulmonary dendritic cells, T helper type 2 cells, and mast cells is crucial mediators in the pathology of soot- or CB-induced respiratory disease. Polyunsaturated fatty acids (PUFAs) were also found to modulate T cells functions in respiratory diseases. Particularly, telomerase reverse transcriptase was found to play the critical role in soot- and CB-induced cardiovascular dysfunctions. In this review, we propose integrated mechanisms of soot- and CB-induced toxicity emphasizing the role of inflammatory mediators and oxidative stress. We also suggest use of antioxidants and PUFAs as protective strategies against soot- and CB-induced disorders.
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Affiliation(s)
- Rituraj Niranjan
- Department of Biological Sciences and Bioengineering (BSBE), Indian Institute of Technology Kanpur, Kanpur, India
| | - Ashwani Kumar Thakur
- Department of Biological Sciences and Bioengineering (BSBE), Indian Institute of Technology Kanpur, Kanpur, India
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Kansara K, Patel P, Shah D, Shukla RK, Singh S, Kumar A, Dhawan A. TiO2 nanoparticles induce DNA double strand breaks and cell cycle arrest in human alveolar cells. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2015; 56:204-17. [PMID: 25524809 DOI: 10.1002/em.21925] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Revised: 10/19/2014] [Accepted: 10/29/2014] [Indexed: 05/25/2023]
Abstract
TiO2 nanoparticles (NPs) have the second highest global annual production (∼3000 tons) among the metal-containing NPs. These NPs are used as photocatalysts for bacterial disinfection, and in various other consumer products including sunscreen, food packaging, therapeutics, biosensors, surface cleaning agents, and others. Humans are exposed to these NPs during synthesis (laboratory), manufacture (industry), and use (consumer products, devices, medicines, etc.), as well as through environmental exposures (disposal). Hence, there is great concern regarding the health effects caused by exposure to NPs and, in particular, to TiO2 NPs. In the present study, the genotoxic potential of TiO2 NPs in A549 cells was examined, focusing on their potential to induce ROS, different types of DNA damage, and cell cycle arrest. We show that TiO2 NPs can induce DNA damage and a corresponding increase in micronucleus frequency, as evident from the comet and cytokinesis-block micronucleus assays. We demonstrate that DNA damage may be attributed to increased oxidative stress and ROS generation. Furthermore, genomic and proteomic analyses showed increased expression of ATM, P53, and CdC-2 and decreased expression of ATR, H2AX, and Cyclin B1 in A549 cells, suggesting induction of DNA double strand breaks. The occurrence of double strand breaks was correlated with cell cycle arrest in G2/M phase. Overall, the results indicate the potential for genotoxicity following exposure to these TiO2 NPs, suggesting that use should be carefully monitored.
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Affiliation(s)
- Krupa Kansara
- Institute of Life Sciences, Ahmedabad University, University Road, Navrangpura, Ahmedabad, Gujarat, India
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Toxic effects following phosgene exposure of human epithelial lung cells in vitro using a CULTEX® system. Toxicol In Vitro 2011; 25:2080-7. [PMID: 21945045 DOI: 10.1016/j.tiv.2011.09.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2011] [Revised: 09/05/2011] [Accepted: 09/06/2011] [Indexed: 11/22/2022]
Abstract
The aim of the present study was to investigate toxic effects following phosgene exposure of human epithelial lung cells (A549) in vitro using a CULTEX® system. In particular, toxic effects regarding early biomarkers emerging during the latency period following exposure might be of great value for medical treatment. Cells cultured on semi-permeable membranes were directly exposed at the liquid-air interface to different concentrations of phosgene, or dry medical air. Cell membrane integrity (leakage of LDH), metabolic activity (reduction of Alamar Blue), oxidative damage (GSH, and HO-1, in cell lysates), and release of IL-8, were studied. For most of the above-mentioned biological end-point markers, significant changes could be assessed following a 20 min exposure to 1.0 ppm and 2.0 ppm phosgene. Moreover, except for IL-8, all biological marker profiles showed to be in line with results obtained by others in animal studies. The C×t value of 40 ppm min appeared to be constant. The overall results suggest that at 4 h post-exposure a maximal level of toxicity was achieved. Our results demonstrate the suitability of a CULTEX® system to detect toxic effects induced by phosgene on human epithelial lung cells, which may contribute to the discovery of early biomarkers for new medical countermeasures.
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Ye Y, Liu J, Chen M, Sun L, Lan M. In vitro toxicity of silica nanoparticles in myocardial cells. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2010; 29:131-7. [PMID: 21787594 DOI: 10.1016/j.etap.2009.12.002] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2009] [Revised: 12/14/2009] [Accepted: 12/19/2009] [Indexed: 05/20/2023]
Abstract
In the present study, toxicities of silica nanoparticles with sizes of 21 and 48nm were assessed in myocardial H9c2(2-1) cells using the methylthiazolyldiphenyl-tetrazolium bromide reduction and lactate dehydrogenase assays. Cell injuries were characterized by morphological changes using hematoxylin and eosin staining. Reactive oxygen species, malondialdehyde and glutathione were measured to evaluate the levels of oxidative stress. To elucidate mechanisms, cell cycle distributions and the expressions of p53, p21 and Bax were also analyzed. Results showed that silica nanoparticles produced cytotoxicities in size, dose (0.1-1.6mg/ml) and time (12, 24, 36 and 48h exposure) dependent manners. Moreover, the particles caused oxidative stress, induced G1 phase arrest and upregulated levels of p53 and p21. Taken together, these data suggested that cell injuries were triggered by the generation of oxidative stress; p53 and p21 mediated G1 phase arrest is a potential mechanistic pathway of silica nanoparticles induced damage in H9c2(2-1) cells.
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Affiliation(s)
- Yiyi Ye
- State Key Laboratory of Bioreactor Engineering and School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
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Ye Y, Liu J, Xu J, Sun L, Chen M, Lan M. Nano-SiO2 induces apoptosis via activation of p53 and Bax mediated by oxidative stress in human hepatic cell line. Toxicol In Vitro 2010; 24:751-8. [PMID: 20060462 DOI: 10.1016/j.tiv.2010.01.001] [Citation(s) in RCA: 137] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2009] [Revised: 10/28/2009] [Accepted: 01/04/2010] [Indexed: 10/20/2022]
Abstract
Nanoparticles such as nano-SiO(2) are increasingly used in food, cosmetics, diagnosis, imaging and drug delivery. However, toxicological data of nano-SiO(2) on hepatic cells in vitro and their detailed molecular mechanisms still remain unclear. In order to assess toxicity of nano-SiO(2), L-02 cells were exposed to 0.2, 0.4 and 0.6 mg/ml of SiO(2) colloids (21, 48 and 86 nm) for 12, 24, 36 and 48h. Lactate dehydrogenase released from damaged cells were quantified, cellular ultrastructural organization was observed, and the levels of reactive oxygen species (ROS), lipid peroxidation and glutathione were measured. Apoptosis induced by 21 nm SiO(2) was characterized by annexin V-FITC/PI staining and DNA ladder assay. Furthermore, apoptosis related proteins such as p53, Bax and Bcl-2 were analyzed by using western blot analysis. Our data indicated that nano-SiO(2) caused cytotoxicity in size, dose and time dependent manners. Oxidative stress and apoptosis were induced by exposure to 21 nm SiO(2). Moreover, the expression of p53 and Bax was increased in time and dose dependent patterns, whereas the expression of Bcl-2 was not significantly changed. In conclusion, ROS-mediated oxidative stress, the activation of p53 and up-regulation of Bax/Bcl-2 ratio are involved in mechanistic pathways of 21 nm SiO(2) induced apoptosis in L-02 cells.
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Affiliation(s)
- Yiyi Ye
- State Key Laboratory of Bioreactor Engineering, Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
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Jones CF, Grainger DW. In vitro assessments of nanomaterial toxicity. Adv Drug Deliv Rev 2009; 61:438-56. [PMID: 19383522 PMCID: PMC2763955 DOI: 10.1016/j.addr.2009.03.005] [Citation(s) in RCA: 435] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2008] [Accepted: 03/30/2009] [Indexed: 02/07/2023]
Abstract
Nanotechnology has grown from a scientific interest to a major industry with both commodity and specialty nanomaterial exposure to global populations and ecosystems. Sub-micron materials are currently used in a wide variety of consumer products and in clinical trials as drug delivery carriers and imaging agents. Due to the expected growth in this field and the increasing public exposure to nanomaterials, both from intentional administration and inadvertent contact, improved characterization and reliable toxicity screening tools are required for new and existing nanomaterials. This review discusses current methodologies used to assess nanomaterial physicochemical properties and their in vitro effects. Current methods lack the desired sensitivity, reliability, correlation and sophistication to provide more than limited, often equivocal, pieces of the overall nanomaterial performance parameter space, particularly in realistic physiological or environmental models containing cells, proteins and solutes. Therefore, improved physicochemical nanomaterial assays are needed to provide accurate exposure risk assessments and genuine predictions of in vivo behavior and therapeutic value. Simpler model nanomaterial systems in buffer do not accurately duplicate this complexity or predict in vivo behavior. A diverse portfolio of complementary material characterization tools and bioassays are required to validate nanomaterial properties in physiology.
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Affiliation(s)
- Clinton F Jones
- Department of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, Salt Lake City, UT 84112-5820, USA
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Sgro LA, Simonelli A, Pascarella L, Minutolo P, Guarnieri D, Sannolo N, Netti P, D'Anna A. Toxicological properties of nanoparticles of organic compounds (NOC) from flames and vehicle exhausts. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2009; 43:2608-2613. [PMID: 19452924 DOI: 10.1021/es8034768] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We examined the biological reactivity in vitro of nanoparticles of organic compounds (NOC) with diameters, d = 1-3 nm, a class of combustion-generated particulate relatively unstudied compared to larger more graphitic soot particles because of their small size even though they may contribute significantly to the organic fraction of PM sampled from vehicle exhausts and urban atmospheres. We tested NOC samples collected from 2004 model vehicle emissions and laboratory flames. NOC produced a dose dependent mutagenic response in Salmonella bacteria, suggesting that NOC may add significantly to the overall mutagenicity of vehicle emissions. Incubation with peptides caused agglomeration and precipitate of the otherwise stable NOC suspension, but the chemical and/or physical nature of the NOC-peptide interactions could not be resolved. A significant cytotoxic response was measured above a critical dose of NOC in mouse embryo fibroblasts NIH3T3 cells along with possible evidence of cellular uptake by optical and confocal microscopy. The toxicological assays showed that NOC collected from flames and vehicle exhausts effectively interacted in vitro with both prokaryotic and eukaryotic cells. Differences in mutagenic potencies observed for various Salmonella strains with and without metabolic activation indicate differences in the chemical composition of NOC collected from different vehicles and flames.
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Affiliation(s)
- L A Sgro
- Department of Chemical Engineering, University of Naples, Federico II, P. Tecchio 80, 80125 Naples, Italy.
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