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A novel preclinical model of environment-like combined benzene, toluene, ethylbenzene, and xylenes (BTEX) exposure: Behavioral and neurochemical findings. Neurotoxicol Teratol 2022; 91:107076. [DOI: 10.1016/j.ntt.2022.107076] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Revised: 01/14/2022] [Accepted: 02/08/2022] [Indexed: 12/07/2022]
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Davidson CJ, Hannigan JH, Bowen SE. Effects of inhaled combined Benzene, Toluene, Ethylbenzene, and Xylenes (BTEX): Toward an environmental exposure model. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2021; 81:103518. [PMID: 33132182 DOI: 10.1016/j.etap.2020.103518] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 10/14/2020] [Accepted: 10/15/2020] [Indexed: 06/11/2023]
Abstract
Combined environmental exposures to the volatile organic compounds (VOCs) Benzene, Toluene, Ethylbenzene, and Xylene (BTEX) pose clear risks to public health. Research into these risks is under-studied even as BTEX levels in the atmosphere are predicted to rise. This review focuses on the available literature using single- and combined-BTEX component inhaled solvent exposures in animal models, necessarily also drawing on findings from models of inhalant abuse and occupational exposures. Health effects of these exposures are discussed for multiple organ systems, but with particular attention on neurobehavioral outcomes such as locomotor activity, impulsivity, learning, and psychopharmacological responses. It is clear that animal models have significant differences in the concentrations, durations and patterns of exposure. Experimental evidence of the deleterious health and neurobehavioral consequences of exposures to the individual components of BTEX were found, but these effects were typically assessed using concentrations and exposure patterns not characteristic of environmental exposure. Future studies with animal models designed appropriately to explore combined BTEX will be necessary and advantageous to discovering health outcomes and more subtle neurobehavioral impacts of long-term environmental exposures.
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Affiliation(s)
| | - John H Hannigan
- Department of Psychology, Wayne State University, Detroit, MI, USA; Department of Obstetrics & Gynecology, Wayne State University, Detroit, MI, USA; Merrill Palmer Skillman Institute for Child & Family Development, Wayne State University, Detroit, MI, USA; Center for Urban Responses to Environmental Stressors, Wayne State University, Detroit, MI, USA
| | - Scott E Bowen
- Department of Psychology, Wayne State University, Detroit, MI, USA; Center for Urban Responses to Environmental Stressors, Wayne State University, Detroit, MI, USA.
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Lin YJ, Ling MP, Chen SC, Chen WY, Hsieh NH, Cheng YH, You SH, Chou WC, Lin MC, Liao CM. Mixture risk assessment due to ingestion of arsenic, copper, and zinc from milkfish farmed in contaminated coastal areas. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:14616-14626. [PMID: 28452032 DOI: 10.1007/s11356-017-8982-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 04/03/2017] [Indexed: 06/07/2023]
Abstract
Human health risks associated with the consumption of metal-contaminated fish over extended periods have become a concern particularly in Taiwan, where fish is consumed on a large scale. This study applied the interaction-based hazard index (HI) to assess the mixture health risks for fishers and non-fishers who consume the arsenic (As), copper (Cu), and zinc (Zn) contaminated milkfish from As-contaminated coastal areas in Taiwan, taking into account joint toxic actions and potential toxic interactions. We showed that the interactions of As-Zn and Cu-Zn were antagonistic, whereas As-Cu interaction was additive. We found that HI estimates without interactions considered were 1.3-1.6 times higher than interactive HIs. Probability distributions of HI estimates for non-fishers were less than 1, whereas all 97.5%-tile HI estimates for fishers were >1. Analytical results revealed that the level of inorganic As in milkfish was the main contributor to HIs, indicating a health risk posed to consumers of fish farmed in As-contaminated areas. However, we found that Zn supplementation could significantly decrease As-induced risk of hematological effect by activating a Zn-dependent enzyme. In order to improve the accuracy of health risk due to exposure to multiple metals, further toxicological data, regular environmental monitoring, dietary survey, and refinement approaches for interactive risk assessment are warranted.
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Affiliation(s)
- Yi-Jun Lin
- Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, 10617, Taiwan
| | - Min-Pei Ling
- Department of Food Science, National Taiwan Ocean University, Keelung City, 20224, Taiwan.
| | - Szu-Chieh Chen
- Department of Public Health, Chung Shan Medical University, Taichung, 40242, Taiwan
| | - Wei-Yu Chen
- Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan
| | - Nan-Hung Hsieh
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, 77845, USA
| | - Yi-Hsien Cheng
- Institute of Computational Comparative Medicine, Kansas State University, Manhattan, KS, 66506, USA
| | - Shu-Han You
- National Institute of Environmental Health Sciences, National Health Research Institutes, Miaoli County, 35053, Taiwan
| | - Wei-Chun Chou
- National Institute of Environmental Health Sciences, National Health Research Institutes, Miaoli County, 35053, Taiwan
| | - Ming-Chao Lin
- Center for General Education, Nanhua University, Chiayi County, 62249, Taiwan
| | - Chung-Min Liao
- Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, 10617, Taiwan.
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Fortoul TI, Avila-Costa MR, Espejel-Maya G, Mussali-Galante P, Avila-Casado MDC, Hernández-Serrato MI, Saldivar-Osorio L. Metal mixture inhalation (Cd-Pb) and its effects on the bronchiolar epithelium. An ultrastructural approach. Toxicol Ind Health 2016; 20:69-75. [PMID: 15807410 DOI: 10.1191/0748233704th196oa] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The current study explores the effects of the inhalation of lead (Pb), Cd and its mixture (Pb-Cd) in a mice model, analysing metal concentrations in the lung, and the morphological modifications in the bronchiolar epithelium identified by scanning electron microscopy after eight weeks of inhalation. Our results indicate that metal concentrations in lung were higher compared to controls; however, Pb concentrations drastically decrease in the mixture. This reduction was also observed in the inhalation chamber. The main changes observed in the bronchiole were mostly in the mixture. The modifications were mainly given by Cd alone and in the mixture, with a decreased number of nonciliated bronchiolar cells and an increased number of bundles of dividing cells. The additive effect of Pb-Cd is suggested, as the extensive damage observed was more evident when mice were exposed to the mixture, and the results endured more research in the area of inhaled mixtures.
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Affiliation(s)
- Teresa I Fortoul
- Departamento de Biología Celular y Tisular, Facultad de Medicina, National University of Mexico, Mexico City, Mexico.
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Motawei SM, Gouda HE. Screening of Blood Levels of Mercury, Cadmium, and Copper in Pregnant Women in Dakahlia, Egypt: New Attention to an Old Problem. Biol Trace Elem Res 2016; 171:308-314. [PMID: 26521060 DOI: 10.1007/s12011-015-0525-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 09/24/2015] [Indexed: 01/31/2023]
Abstract
Heavy metals toxicity is a prevalent health problem particularly in developing countries. Mercury and cadmium are toxic elements that have no physiologic functions in human body. They should not be present in the human body by any concentration. Copper, on the other hand, is one of the elements that are essential for normal cell functions and a deficiency as well as an excess of which can cause adverse health effects. To test blood levels of mercury, cadmium, and copper in pregnant women in Dakahlia, Egypt. Using atomic absorption spectrophotometry, blood levels of cadmium, mercury, and copper were measured in 150 pregnant women attending to the antenatal care in Mansoura University Hospital in Dakahlia governorate, Egypt. The mean ± SD of blood mercury, cadmium, and copper levels were found to be far from their levels in the population surveys carried in developed countries like United States of America (USA) and Canada. Heavy metal intoxication and accumulation is a major health hazard. Developing countries, including Egypt, still lack many of the regulatory policies and legislations to control sources of pollution exposure. This should be dealt with in order to solve this problem and limit its health consequences.
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Affiliation(s)
- Shimaa M Motawei
- Forensic Medicine & Clinical Toxicology Department, Faculty of Medicine, Mansoura University, Mansoura, Egypt.
| | - Hossam E Gouda
- Obstetrics & Gynaecology Department, Faculty of Medicine, Mansoura University, Mansoura, Egypt
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Khezeli T, Daneshfar A, Sahraei R. Emulsification liquid–liquid microextraction based on deep eutectic solvent: An extraction method for the determination of benzene, toluene, ethylbenzene and seven polycyclic aromatic hydrocarbons from water samples. J Chromatogr A 2015; 1425:25-33. [DOI: 10.1016/j.chroma.2015.11.007] [Citation(s) in RCA: 129] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 11/02/2015] [Accepted: 11/02/2015] [Indexed: 02/04/2023]
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Ning XA, Wang JY, Li RJ, Wen WB, Chen CM, Wang YJ, Yang ZY, Liu JY. Fate of volatile aromatic hydrocarbons in the wastewater from six textile dyeing wastewater treatment plants. CHEMOSPHERE 2015; 136:50-55. [PMID: 25930124 DOI: 10.1016/j.chemosphere.2015.03.086] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Revised: 01/30/2015] [Accepted: 03/21/2015] [Indexed: 06/04/2023]
Abstract
The occurrence and removal of benzene, toluene, ethylbenzene, xylenes, styrene and isopropylbenzene (BTEXSI) from 6 textile dyeing wastewater treatment plants (TDWTPs) were investigated in this study. The practical capacities of the 6 representative plants, which used the activated sludge process, ranged from 1200 to 26000 m(3) d(-1). The results indicated that BTEXSI were ubiquitous in the raw textile dyeing wastewater, except for isopropylbenzene, and that toluene and xylenes were predominant in raw wastewaters (RWs). TDWTP-E was selected to study the residual BTEXSI at different stages. The total BTEXSI reduction on the aerobic process of TDWTP-E accounted for 82.2% of the entire process. The total BTEXSI concentrations from the final effluents (FEs) were observed to be below 1 μg L(-1), except for TDWTP-F (2.12 μg L(-1)). Volatilization and biodegradation rather than sludge sorption contributed significantly to BTEXSI removal in the treatment system. BTEXSI were not found to be the main contaminants in textile dyeing wastewater.
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Affiliation(s)
- Xun-An Ning
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China.
| | - Jing-Yu Wang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China.
| | - Rui-Jing Li
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Wei-Bin Wen
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Chang-Min Chen
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Yu-Jie Wang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Zuo-Yi Yang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Jing-Yong Liu
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
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von Stackelberg K, Guzy E, Chu T, Henn BC. Exposure to Mixtures of Metals and Neurodevelopmental Outcomes: A Multidisciplinary Review Using an Adverse Outcome Pathway Framework. RISK ANALYSIS : AN OFFICIAL PUBLICATION OF THE SOCIETY FOR RISK ANALYSIS 2015; 35:971-1016. [PMID: 26096925 PMCID: PMC5108657 DOI: 10.1111/risa.12425] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Current risk assessment guidance calls for an individual chemical-by-chemical approach that fails to capture potential interactive effects of exposure to environmental mixtures and genetic variability. We conducted a review of the literature on relationships between prenatal and early life exposure to mixtures of lead (Pb), arsenic (As), cadmium (Cd), and manganese (Mn) with neurodevelopmental outcomes. We then used an adverse outcome pathway (AOP) framework to integrate lines of evidence from multiple disciplines based on evolving guidance developed by the Organization for Economic Cooperation and Development (OECD). Toxicological evidence suggests a greater than additive effect of combined exposures to As-Pb-Cd and to Mn with any other metal, and several epidemiologic studies also suggest synergistic effects from binary combinations of Pb-As, Pb-Cd, and Pb-Mn. The exposure levels reported in these epidemiologic studies largely fall at the high-end (e.g., 95th percentile) of biomonitoring data from the National Health and Nutrition Examination Survey (NHANES), suggesting a small but significant potential for high-end exposures. This review integrates multiple data sources using an AOP framework and provides an initial application of the OECD guidance in the context of potential neurodevelopmental toxicity of several metals, recognizing the evolving nature of regulatory interpretation and acceptance.
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Affiliation(s)
- Katherine von Stackelberg
- Harvard Center for Risk Analysis, Boston, MA 02215;
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA 02215
| | - Elizabeth Guzy
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA 02215
| | - Tian Chu
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA 02215
| | - Birgit Claus Henn
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA 02215
- Now at the Department of Environmental Health, Boston University School of Public Health, Boston, MA 02118
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Tian D, Zheng W, He G, Zheng Y, Andersen ME, Tan H, Qu W. Predicting cytotoxicity of complex mixtures in high cancer incidence regions of the Huai River Basin based on GC-MS spectrum with partial least squares regression. ENVIRONMENTAL RESEARCH 2015; 137:391-397. [PMID: 25614340 DOI: 10.1016/j.envres.2014.12.027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Revised: 12/29/2014] [Accepted: 12/30/2014] [Indexed: 06/04/2023]
Abstract
Complex mixture exposures, such as those associated with water sources, are an important issue in health risk assessment. This study assessed the cytotoxicity of chemical mixtures extracted from water sources in regions of the Huai River Basin with high cancer incidences and built statistical models of cytotoxicity based on pollution profiles that were measured with gas chromatography-mass spectrometry (GC-MS). Both surface and ground waters were collected from rural water sources of Shenqiu County, Henan Province of China from 2008 to 2011 and extracted with XAD-2 resigns. Cytotoxicity was evaluated with Chinese hamster ovary K1 (CHO-K1) cells and compared against the pollution profiles of the extracts. IC50 of water samples ranged from 0.023 to 0.338L-eq/mL. The pollutants in waters determined by GC-MS are complex and some of the compounds that contributed to cytotoxicity lack toxicity data. A partial least squares (PLS) regression model of cytotoxicity was built based on linear aggregation of predictor variables (i.e., peaks for single compounds in the gas chromatograms). The PLS model contains 2 PLS factors extracted from 141 variables. The model was validated internally with training data permutation and externally with a test sample. The model explained 92% of the cytotoxicity in the training samples and 40% in the test sample. This approach provides a general, rapid method for relating water toxicity to GC-MS chromatograms and for predicting the compounds that contribute most to toxicity.
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Affiliation(s)
- Dajun Tian
- Key Laboratory of Public Health and Safety, Ministry of Education, Department of Environmental Health, School of Public Health, Fudan University, Yi Xue Yuan Road 138, Shanghai 200032, China
| | - Weiwei Zheng
- Key Laboratory of Public Health and Safety, Ministry of Education, Department of Environmental Health, School of Public Health, Fudan University, Yi Xue Yuan Road 138, Shanghai 200032, China
| | - Gengsheng He
- Key Laboratory of the Public Health Safety, Ministry of Education, Department of Nutrition and Food Hygiene, Fudan University, Shanghai 200032, China
| | - Yuxin Zheng
- Chinese Center for Disease Control and Prevention, Nan Wei Road 29, Beijing 100050, China
| | - Melvin E Andersen
- Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709, USA
| | - Hui Tan
- Key Laboratory of the Public Health Safety, Ministry of Education, Department of Childhood and Adolescent, Fudan University, Shanghai 200032, China
| | - Weidong Qu
- Key Laboratory of Public Health and Safety, Ministry of Education, Department of Environmental Health, School of Public Health, Fudan University, Yi Xue Yuan Road 138, Shanghai 200032, China.
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Martínez-Pacheco M, Hidalgo-Miranda A, Romero-Córdoba S, Valverde M, Rojas E. MRNA and miRNA expression patterns associated to pathways linked to metal mixture health effects. Gene 2013; 533:508-14. [PMID: 24080485 DOI: 10.1016/j.gene.2013.09.049] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Accepted: 09/13/2013] [Indexed: 12/31/2022]
Abstract
Metals are a threat to human health by increasing disease risk. Experimental data have linked altered miRNA expression with exposure to some metals. MiRNAs comprise a large family of non-coding single-stranded molecules that primarily function to negatively regulate gene expression post-transcriptionally. Although several human populations are exposed to low concentrations of As, Cd and Pb as a mixture, most toxicology research focuses on the individual effects that these metals exert. Thus, this study aims to evaluate global miRNA and mRNA expression changes induced by a metal mixture containing NaAsO2, CdCl2, Pb(C2H3O2)2·3H2O and to predict possible metal-associated disease development under these conditions. Our results show that this metal mixture results in a miRNA expression profile that may be responsible for the mRNA expression changes observed under experimental conditions in which coding proteins are involved in cellular processes, including cell death, growth and proliferation related to the metal-associated inflammatory response and cancer.
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Affiliation(s)
- M Martínez-Pacheco
- Universidad Nacional Autónoma de México, Instituto de Investigaciones Biomédicas, Departamento de Medicina Genómica y Toxicología Ambiental, C.U., 04510 México, México
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Olawoyin R. Exploration of the spatial-Composite Risk Index (CRI) for the characterization of toxicokinetics in petrochemical active areas. CHEMOSPHERE 2013; 92:1207-1213. [PMID: 23714154 DOI: 10.1016/j.chemosphere.2013.04.045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 04/10/2013] [Accepted: 04/12/2013] [Indexed: 06/02/2023]
Abstract
The spatial modeling of the petrochemical active regions in the Niger Delta (ND), Nigeria was carried out through the analysis exploration and extraction of geospatial data and resultant risk maps were generated. The pollutants assessed include; heavy metals, polychlorinated aromatic hydrocarbons (PAHs), benzene-toluene-ethylene-xylene (BTEX), and total petroleum hydrocarbons (TPHs) and properties of the pollutants such as bioaccumulation, persistence and toxicity were used to calculate the Hazard Index (HI) and thus created a ranking system. The Composite Risk Index (CRI) was developed successively considering the concentrations of all pollutants and the computed HI using the samples collected in ND areas of Nigeria. The carcinogenic PAHs showed spatial abundance in the areas sampled and elevated levels of soil heavy metals were also observed. In this study, mathematical tool such as the artificial neural network (ANN) self-organizing map (SOM) and geostatistical analysis such as kriging were applied to develop the risk map of the areas which represent the spatial spread of the CRI. The results show that the application of spatially developed integral risk map for pollutant assessment is effective and facilitates with decision making with regards the environment and humans exposed in this region.
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Affiliation(s)
- Richard Olawoyin
- The John and Willie Leone Family Department of Energy and Mineral Engineering, The Pennsylvania State University, University Park, PA 16802, USA.
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Chang WJ, Joe KT, Park HY, Jeong JD, Lee DH. The relationship of liver function tests to mixed exposure to lead and organic solvents. Ann Occup Environ Med 2013; 25:5. [PMID: 24472152 PMCID: PMC3886255 DOI: 10.1186/2052-4374-25-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Accepted: 02/28/2013] [Indexed: 12/19/2022] Open
Abstract
Objective This study aims to compare liver function indices (aspartate aminotransferase [AST], alanine aminotransferase [ALT], and gamma glutamyl transferase [GGT]) among males who work with lead, organic solvents, or both lead and organic solvents, under the permissible exposure limit (PEL). Methods A total of 593 (out of 2,218) male workers who agreed to share their personal health information for medical research were selected for this study. Those excluded were hepatitis B carriers, individuals exposed to occupational risk factors other than lead and organic solvents, and individuals without liver function results. The 593 were divided into five groups: a lead-exposed group, an organic solvent-exposed group exposed to trichloroethylene (TCE co-exposed solvent group), an organic solvent-exposed group not exposed to trichloroethylene (TCE non-exposed solvent group), a lead and organic solvent-exposed group (mixed exposure group), and a non-exposed group (control group). We performed a one way-analysis of variance (one way-ANOVA) test to compare the geometric means of liver function indices among the groups, using a general linear model (GLM) to adjust for age, work duration, body mass index (BMI), smoking, and alcohol intake. In addition, we performed a binary logistic regression analysis to compare the odds ratios among groups with an abnormal liver function index, according to a cut-off value. Results The ALT and AST of the mixed exposure group were higher than those of the other groups. The GGT of the mixed exposure group was higher than the TCE co-exposed solvent group, but there was no difference among the control group, TCE non-exposed solvent group, lead-exposed group, and mixed exposure group. The same result was evident after adjusting by GLM for age, work duration, BMI, smoking, and alcohol intake, except that ALT from the mixed exposure group showed no difference from the TCE co-exposed solvent group. When the cut-off values of the AST, ALT, and GGT were 40 IU/L, 42 IU/L, and 63 IU/L, respectively, a logistic regression analysis showed no differences in the odds ratios of those who had an abnormal liver function index among the groups. However, if the cut-off values of the AST, ALT, and GGT were 30 IU/L, 30 IU/L, and 40 IU/L, respectively, the odds ratio of the AST in the mixed exposure group was 4.39 (95% CI 1.86-10.40) times higher than the control. Conclusion This study indicates that a mixed exposure to lead and organic solvents is dangerous, even if each single exposure is safe under the permissible exposure limit. Therefore, to ensure occupational health and safety in industry, a continuous efforts to study the effects from exposure to mixed chemicals is needed.
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Affiliation(s)
| | | | | | - Jong-Do Jeong
- Department of Occupational and Environmental Medicine, Pohang Sunlin Hospital, Pohang, South Korea.
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Kasi M, McEvoy J, Padmanabhan G, Khan E. Groundwater remediation using an enricher reactor-permeable reactive biobarrier for periodically absent contaminants. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2011; 83:603-612. [PMID: 21790078 DOI: 10.2175/106143011x12928814444457] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A combined enricher reactor (ER)-permeable reactive biobarrier (PRBB) system was developed to treat groundwater with contaminants that appear in batches. An enricher reactor is an offline reactor used to enrich contaminant degraders by supplying necessary growth materials, and the enriched degraders are used to augment PRBB to increase its performance after a period of contaminant absence. Bench-scale experiments on PRBBs with and without bacterial supply from the enricher reactor were conducted to evaluate PRBB removal performances for benzene, which was used as a model contaminant. Benzene absence periods of 10 and 25 days were tested in the presence and absence of ethanol. The PRBBs without the bioaugmentation from the enricher reactor experienced a decrease in performance from approximately 65% to 30% after benzene reappeared. The presence of ethanol accelerated the benzene removal performance recovery of PRBBs. The 25-day benzene absence period caused greater changes in the bacterial community structure, regardless of the ethanol availability.
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Affiliation(s)
- Murthy Kasi
- Department of Civil Engineering, North Dakota State University, Fargo, North Dakota 58105, USA
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Seliem MK, Komarneni S, Cho Y, Lim T, Shahien M, Khalil A, Abd El-Gaid I. Organosilicas and organo-clay minerals as sorbents for toluene. APPLIED CLAY SCIENCE 2011; 52:184-189. [DOI: 10.1016/j.clay.2011.02.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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Pohl HR, Mumtaz MM, Scinicariello F, Hansen H. Binary weight-of-evidence evaluations of chemical interactions--15 years of experience. Regul Toxicol Pharmacol 2009; 54:264-71. [PMID: 19445993 DOI: 10.1016/j.yrtph.2009.05.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2008] [Revised: 03/27/2009] [Accepted: 05/07/2009] [Indexed: 10/20/2022]
Abstract
The paper reflects on the last 15years of experience in the field of mixtures risk assessment. It summarizes results found in various documents developed by the Agency for Toxic Substances and Disease Registry (ATSDR) of the weight-of-evidence (WOE) approach applied to 380 binary combinations of chemicals. Of these evaluations, 156 assessments indicated possible additivity of effects [=], 76 indicated synergism (greater-than-additive effects [>]), and 57 indicated antagonism (less-than-additive effects [<]). However, 91 combinations lacked the minimum information needed for making any assessments and, hence, were undetermined. The paper provides examples of the rationale behind some of the WOE decisions and discusses the importance of expert judgments in risk assessment evaluations. Examples are given regarding the importance of human variability in mixtures' ability to affect human health and regarding the dose versus effect relationships.
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Affiliation(s)
- Hana R Pohl
- Agency for Toxic Substances and Disease Registry, U.S. Department of Health and Human Services, Division of Toxicology and Environmental Medicine, 1600 Clifton Road, F-32, Atlanta, GA 30333, USA.
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Stewart AG, Carter J. Towards the development of a multidisciplinary understanding of the effects of toxic chemical mixtures on health. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2009; 31:239-251. [PMID: 19023667 DOI: 10.1007/s10653-008-9210-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2008] [Revised: 09/10/2008] [Accepted: 09/11/2008] [Indexed: 05/27/2023]
Abstract
Mixtures can be divided into simple (chemicals with comparable properties--health risk assessments on the chemicals) and complex, which can be further subdivided into defined (a reasonably distinct composition, created at a specific time and place despite dissimilar components--risk assessments on the common source) and coincidental (chemicals without similar properties or constant composition in time or space-risk assessments on the receptor). Interactions recognized are: independent action, dose addition (additivity), and potentiation (synergy and antagonism). Unpredicted outcomes need recognition. New approaches in higher education and multidisciplinary investigations are essential. The community of the Society for Environmental Geochemistry and Health should help clarify points such as when transformations in mixtures may become important enough to alter the classification and the risk assessment. The multidisciplinary community is also well placed to support the integration of non-chemical influences into mixture analysis and to contribute to the investigation of cumulative and multiple exposures.
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Affiliation(s)
- Alex G Stewart
- Cheshire and Merseyside Health Protection Unit, Microbiology Laboratory, Countess of Chester Health Park, London Road, Chester CH12UL, UK.
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17
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Demchuk E, Ruiz P, Wilson JD, Scinicariello F, Pohl HR, Fay M, Mumtaz MM, Hansen H, De Rosa CT. Computational Toxicology Methods in Public Health Practice. Toxicol Mech Methods 2008; 18:119-35. [DOI: 10.1080/15376510701857148] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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18
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Lee JJ, Jang CS, Liang CP, Liu CW. Assessing carcinogenic risks associated with ingesting arsenic in farmed smeltfish (Ayu, Plecoglossus altirelis) in aseniasis-endemic area of Taiwan. THE SCIENCE OF THE TOTAL ENVIRONMENT 2008; 403:68-79. [PMID: 18584852 DOI: 10.1016/j.scitotenv.2008.05.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2007] [Revised: 04/29/2008] [Accepted: 05/07/2008] [Indexed: 05/26/2023]
Abstract
This study spatially analyzed potential carcinogenic risks associated with ingesting arsenic (As) contents in aquacultural smeltfish (Plecoglossus altirelis) from the Lanyang Plain of northeastern Taiwan. Sequential indicator simulation (SIS) was adopted to reproduce As exposure distributions in groundwater based on their three-dimensional variability. A target cancer risk (TR) associated with ingesting As in aquacultural smeltfish was employed to evaluate the potential risk to human health. The probabilistic risk assessment determined by Monte Carlo simulation and SIS is used to propagate properly the uncertainty of parameters. Safe and hazardous aquacultural regions were mapped to elucidate the safety of groundwater use. The TRs determined from the risks at the 95th percentiles exceed one millionth, indicating that ingesting smeltfish that are farmed in the highly As-affected regions represents a potential cancer threat to human health. The 95th percentile of TRs is considered in formulating a strategy for the aquacultural use of groundwater in the preliminary stage.
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Affiliation(s)
- Jin-Jing Lee
- Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, 106, Taiwan, Republic of China
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19
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Pohl HR, Tarkowski S, Buczynska A, Fay M, De Rosa CT. Chemical exposures at hazardous waste sites: Experiences from the United States and Poland. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2008; 25:283-91. [PMID: 21783864 DOI: 10.1016/j.etap.2007.12.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2007] [Revised: 12/03/2007] [Accepted: 12/05/2007] [Indexed: 05/23/2023]
Abstract
The U.S. Agency for Toxic Substances and Disease Registry (ATSDR) and the Polish Nofer Institute of Occupational Health collaborate on issues related to hazardous chemical exposure at or near hazardous waste sites. This paper outlines the scope of hazardous chemical exposure in the United States and in Poland and identifies priority chemicals and chemical mixtures. Special attention is paid to exposures to metals and to evaluation of the health risks associated with those exposures. Studies in the United States indicate that exposure to hazardous waste site chemicals may be associated with an increased risk of adverse developmental - specifically cardiovascular and neurodevelopmental - effects.
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Affiliation(s)
- Hana R Pohl
- Agency for Toxic Substances and Disease Registry, US Department of Health and Human Services, Atlanta, GA, USA
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20
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Farhadian M, Duchez D, Vachelard C, Larroche C. Monoaromatics removal from polluted water through bioreactors-a review. WATER RESEARCH 2008; 42:1325-1341. [PMID: 18023838 DOI: 10.1016/j.watres.2007.10.021] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2007] [Revised: 09/27/2007] [Accepted: 10/16/2007] [Indexed: 05/25/2023]
Abstract
Water contaminated by oil products is becoming a major problem in water supplies as these organic compounds cause hazards for human health. Different types of aerobic and anaerobic bioreactors have been widely used for water cleanup from organic pollutants such as petroleum hydrocarbons. Many studies report that aerobic biofilm processes are a very efficient method for monoaromatic hydrocarbons removal from contaminated water as they are able to reduce up to 99% of the pollutants from water, but generally these works do not discuss possible pollutant loss through gas stripping. On the other hand, some research is related to the ability of anaerobic bioreactors for monoaromatics treatment and results have shown that anaerobic immobilized reactors are able to remove monoaromatic compounds from water with maximal efficiencies between 95-99%. But here again, no data are found about the amount of volatile organic compounds that can be found in the biogas. Also, the data generated when a solid biomass support (activated carbon, polyurethane, etc.) is present in the medium do not take care about possible solute sorption phenomena. This paper reviews various properties of monoaromatic compounds including benzene, toluene, ethylbenzene and mixture of xylenes. The sources of pollutants, various analytical methods suitable for identification and quantitative measurement of monoaromatics, and knowledge gained on the true removal rates by aerobic and anaerobic bioreactors are reviewed and discussed in this study.
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Affiliation(s)
- Mehrdad Farhadian
- Polytech Clermont-Ferrand, Université Blaise Pascal, Aubière, Cedex, France
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21
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Pohl HR, Abadin HG. Chemical mixtures: evaluation of risk for child-specific exposures in a multi-stressor environment. Toxicol Appl Pharmacol 2008; 233:116-25. [PMID: 18353412 DOI: 10.1016/j.taap.2008.01.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2007] [Accepted: 01/25/2008] [Indexed: 10/22/2022]
Abstract
Evaluating the health impact from exposure to chemical mixtures is multifaceted. One component is exposure. Exposure, and consequently risk assessment for mixtures and chemicals in general, are often viewed in terms of a given exposure to a given population at a given location over a given time period. However, environmental exposures are present throughout human lifetime. As a result, an evaluation of risk must include the distinctive characteristics related to chemical exposures which will impact risk depending upon the particular life stage where exposure occurs. Risks to offspring may be associated with unique exposures in utero, during infancy, childhood, or adolescent periods. For example, exposure of infants to anthropogenic chemicals via breast milk may be of concern. The Agency for Toxic Substances and Disease Registry's (ATSDR's) approach to evaluating risks associated with exposure to mixtures of chemicals is presented. In addition to the breast milk issues, indoor exposure to combined air pollutants, drinking water contaminants, and soil and dust contaminants are discussed. The difference between a mixture's risk evaluation for children and adults is in the distinct exposure scenarios resulting from variations in behavior, physiology, and/or pharmacokinetics between adults and children rather than in the method for the specific mixtures evaluation per se.
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Affiliation(s)
- H R Pohl
- Agency for Toxic Substances and Disease Registry, US Department of Health and Human Services, Atlanta, Georgia, USA.
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22
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Saint-Georges F, Abbas I, Billet S, Verdin A, Gosset P, Mulliez P, Shirali P, Garçon G. Gene expression induction of volatile organic compound and/or polycyclic aromatic hydrocarbon-metabolizing enzymes in isolated human alveolar macrophages in response to airborne particulate matter (PM2.5). Toxicology 2007; 244:220-30. [PMID: 18178302 DOI: 10.1016/j.tox.2007.11.016] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2007] [Revised: 11/19/2007] [Accepted: 11/22/2007] [Indexed: 11/19/2022]
Abstract
To contribute to improve the knowledge of the underlying mechanisms of action involved in air pollution particulate matter (PM)-induced cytotoxicity, we were interested in the metabolic activation of volatile organic compounds (VOC) and/or polycyclic aromatic hydrocarbons (PAH) coated onto Dunkerque City's PM2.5 in human alveolar macrophages (AM) isolated from bronchoalveolar lavage fluid (BALF). This in vitro cell lung model is closer to the normal in vivo situation than other lung cell lines, notably in the characteristics that AM display in terms of gene expression of phase I and phase II-metabolizing enzymes. The bronchoscopic examinations and BAL procedures were carried out without any complications. After 24, 48 and 72h of incubation, calculated lethal concentrations at 10% and 50% of collected airborne PM were 14.93microg PM/mL and 74.63microg PM/mL, respectively, and indicated the higher sensibility of such target lung cells. Moreover, VOC and/or PAH coated onto PM induced gene expression of cytochrome P450 (cyp) 1a1, cyp2e1, nadph quinone oxydo-reductase-1, and glutathione S-transferase-pi 1 and mu 3, versus controls, suggesting thereby the formation of biologically reactive metabolites. In addition, these results suggested the role of physical carrier of carbonaceous core of PM, which can, therefore, increase both the penetration and the retention of attached-VOC into the cells, thereby enabling them to exert a longer induction. Hence, we concluded that the metabolic activation of the very low doses of VOC and/or PAH coated onto Dunkerque City's PM2.5 is one of the underlying mechanisms of action closely involved in its cytotoxicity in isolated human AM in culture.
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Affiliation(s)
- Françoise Saint-Georges
- Service de Pneumologie, Hôpital Saint-Philibert, Groupement Hospitalier de l'Institut Catholique-Faculté Libre de Médecine de Lille, rue du Grand But, BP 249, 59462 Lomme Cedex, France
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23
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Vichi S, Pizzale L, Conte LS, Buxaderas S, López-Tamames E. The occurrence of volatile and semi-volatile aromatic hydrocarbons in virgin olive oils from north-eastern Italy. Food Control 2007. [DOI: 10.1016/j.foodcont.2006.07.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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24
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Ihara A, Kishikawa N, Wada M, Ohba Y, Nakashima K, Kuroda N. Determination of aromatic compounds by high-performance liquid chromatography with on-line photoreactor and peroxyoxalate chemiluminescence detection. LUMINESCENCE 2007; 22:567-74. [PMID: 17768714 DOI: 10.1002/bio.1002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This paper describes a novel high-performance liquid chromatographic (HPLC) method for the determination of aromatic compounds with peroxyoxalate chemiluminescence (PO-CL ) detection following on-line UV irradiation. Aromatic compounds were UV irradiated (254 nm, 15 W) to generate hydrogen peroxide, which was determined via PO-CL detection using a mixture of bis(2,4,6-trichlorophenyl)oxalate (aryloxalate) and 2,4,6,8-tetrathiomorpholinopyrimido[5,4-d]pyrimidine (fluorophore) as a post-column CL reagent. Generation of hydrogen peroxide from aromatic compounds was confirmed using a flow injection analysis (FIA) system incorporating an enzyme column reactor immobilized with catalase. The conditions for UV irradiation were optimized using benzene and monosubstituted benzenes (phenol, benzaldehyde, nitrobenzene and N,N-dimethylaniline) by an HPLC system to evaluate the analytical performance of the proposed system. The detection limits for benzene and monosubstituted benzenes were in the range 2.1-124 pmol/injection at signal:noise (S:N) ratio = 3. Monocyclic and polycyclic hydrocarbons were also employed to investigate their CL properties. The possibility of PO-CL detection for a wide variety of aromatic compounds was shown for the first time.
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Affiliation(s)
- Ayuko Ihara
- Graduate School of Biomedical Sciences, Course of Pharmaceutical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki, Japan
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25
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Nadal M, Kumar V, Schuhmacher M, Domingo JL. Definition and GIS-based characterization of an integral risk index applied to a chemical/petrochemical area. CHEMOSPHERE 2006; 64:1526-35. [PMID: 16442585 DOI: 10.1016/j.chemosphere.2005.11.078] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2005] [Revised: 11/24/2005] [Accepted: 11/30/2005] [Indexed: 05/06/2023]
Abstract
A risk map of the chemical/petrochemical industrial area of Tarragona (Catalonia, Spain) was designed following a two-stage procedure. The first step was the creation of a ranking system (Hazard Index) for a number of different inorganic and organic pollutants: heavy metals, polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polychlorinated aromatic hydrocarbons (PAHs) by applying self-organizing maps (SOM) to persistence, bioaccumulation and toxicity properties of the chemicals. PCBs seemed to be the most hazardous compounds, while the light PAHs showed the minimum values. Subsequently, an Integral Risk Index was developed taking into account the Hazard Index and the concentrations of all pollutants in soil samples collected in the assessed area of Tarragona. Finally, a risk map was elaborated by representing the spatial distribution of the Integral Risk Index with a geographic information system (GIS). The results of the present study seem to indicate that the development of an integral risk map might be useful to help in making-decision processes concerning environmental pollutants.
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Affiliation(s)
- Martí Nadal
- Laboratory of Toxicology and Environmental Health, Rovira i Virgili University, San Lorenzo 21, 43201 Reus, Spain
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26
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de Burbure C, Buchet JP, Leroyer A, Nisse C, Haguenoer JM, Mutti A, Smerhovsky Z, Cikrt M, Trzcinka-Ochocka M, Razniewska G, Jakubowski M, Bernard A. Renal and neurologic effects of cadmium, lead, mercury, and arsenic in children: evidence of early effects and multiple interactions at environmental exposure levels. ENVIRONMENTAL HEALTH PERSPECTIVES 2006; 114:584-90. [PMID: 16581550 PMCID: PMC1440785 DOI: 10.1289/ehp.8202] [Citation(s) in RCA: 197] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Lead, cadmium, mercury, and arsenic are common environmental pollutants in industrialized countries, but their combined impact on children's health is little known. We studied their effects on two main targets, the renal and dopaminergic systems, in > 800 children during a cross-sectional European survey. Control and exposed children were recruited from those living around historical nonferrous smelters in France, the Czech Republic, and Poland. Children provided blood and urine samples for the determination of the metals and sensitive renal or neurologic biomarkers. Serum concentrations of creatinine, cystatin C, and beta2-microglobulin were negatively correlated with blood lead levels (PbB), suggesting an early renal hyperfiltration that averaged 7% in the upper quartile of PbB levels (> 55 microg/L; mean, 78.4 microg/L). The urinary excretion of retinol-binding protein, Clara cell protein, and N-acetyl-beta-d-glucosaminidase was associated mainly with cadmium levels in blood or urine and with urinary mercury. All four metals influenced the dopaminergic markers serum prolactin and urinary homovanillic acid, with complex interactions brought to light. Heavy metals polluting the environment can cause subtle effects on children's renal and dopaminergic systems without clear evidence of a threshold, which reinforces the need to control and regulate potential sources of contamination by heavy metals. Key words: arsenic, biomarkers, cadmium, dopaminergic, heavy metals, interactions, lead, mercury, renal.
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Affiliation(s)
- Claire de Burbure
- Unit of Industrial Toxicology and Occupational Medicine, Faculty of Medicine, Catholic University of Louvain, Clos Chapelle-aux-Champs 30, B-1200 Brussels, Belgium
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27
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Weed DL. Weight of evidence: a review of concept and methods. RISK ANALYSIS : AN OFFICIAL PUBLICATION OF THE SOCIETY FOR RISK ANALYSIS 2005; 25:1545-57. [PMID: 16506981 DOI: 10.1111/j.1539-6924.2005.00699.x] [Citation(s) in RCA: 179] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
"Weight of evidence" (WOE) is a common term in the published scientific and policy-making literature, most often seen in the context of risk assessment (RA). Its definition, however, is unclear. A systematic review of the scientific literature was undertaken to characterize the concept. For the years 1994 through 2004, PubMed was searched for publications in which "weight of evidence" appeared in the abstract and/or title. Of the 276 papers that met these criteria, 92 were selected for review: 71 papers published in 2003 and 2004 (WOE appeared in abstract/title) and 21 from 1994 through 2002 (WOE appeared in title). WOE has three characteristic uses in this literature: (1) metaphorical, where WOE refers to a collection of studies or to an unspecified methodological approach; (2) methodological, where WOE points to established interpretative methodologies (e.g., systematic narrative review, meta-analysis, causal criteria, and/or quality criteria for toxicological studies) or where WOE means that "all" rather than some subset of the evidence is examined, or rarely, where WOE points to methods using quantitative weights for evidence; and (3) theoretical, where WOE serves as a label for a conceptual framework. Several problems are identified: the frequent lack of definition of the term "weight of evidence," multiple uses of the term and a lack of consensus about its meaning, and the many different kinds of weights, both qualitative and quantitative, which can be used in RA. A practical recommendation emerges: the WOE concept and its associated methods should be fully described when used. A research agenda should examine the advantages of quantitative versus qualitative weighting schemes, how best to improve existing methods, and how best to combine those methods (e.g., epidemiology's causal criteria with toxicology's quality criteria).
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28
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Vichi S, Pizzale L, Conte LS, Buxaderas S, López-Tamames E. Simultaneous determination of volatile and semi-volatile aromatic hydrocarbons in virgin olive oil by headspace solid-phase microextraction coupled to gas chromatography/mass spectrometry. J Chromatogr A 2005; 1090:146-54. [PMID: 16196143 DOI: 10.1016/j.chroma.2005.07.007] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
A reliable, simple and relatively fast method for the simultaneous determination of volatile and semi-volatile aromatic hydrocarbons in virgin olive oil was developed, based on headspace solid-phase microextraction (HS-SPME). The investigation regarded eco-contaminants such as alkylated monoaromatic hydrocarbons from C1- to C4-benzenes and light polyaromatic hydrocarbons up to four aromatic rings. Sampling and chromatographic conditions were optimized by using standard solutions in deodorized olive oil and the analytical performances of the method were determined. The proposed method was then applied to real samples of virgin olive oil were the target hydrocarbons could be identified and quantified. Several of them had not been previously quantified in virgin olive oil. Moreover, by the analysis of olive oil samples an additional number of C4-benzenes could be tentatively identified.
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Affiliation(s)
- Stefania Vichi
- Dipartimento di Scienze degli Alimenti, Università degli Studi di Udine, Via Marangoni 97, 33100 Udine, Italy.
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29
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Fortoul TI, Saldivar O L, Espejel-Maya G, Bazarro N P, Mussali-Galante P, Avila-Casado MDC, Colin-Barenque L, Avila-Costa MR. Inhalation of cadmium, lead or its mixture Effects on the bronchiolar structure and its relation with metal tissue concentrations. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2005; 19:329-334. [PMID: 21783493 DOI: 10.1016/j.etap.2004.08.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2003] [Accepted: 08/24/2004] [Indexed: 05/31/2023]
Abstract
The human population in the industrialized world is constantly exposed to chemical mixtures of pollutants such as metals; information about the consequences of the interactions of these compounds on health is scarce. The current study examines the effects of the inhalation of lead (Pb), cadmium (Cd) and Pb-Cd mixture in mice models analyzing the metal concentrations in lung, and the morphological modifications in the bronchiolar epithelium identified by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) after 4 weeks of inhalation. Our results showed that metal concentrations in lung were higher compared to controls; however, Pb concentrations drastically decrease with the mixture. This reduction was also observed in the inhalation chamber. These data correlate with the morphological alterations observed, which consisted of flattened and decreased number of nonciliated bronchiolar cells (NCBC), bald ciliated cells and bundles of NCBC. These modifications were mainly given by Cd, alone or in combination with Pb. The clusters formed by NCBC cells suggest cell proliferation which probably means that after metal inhalation, the cells enhance their proliferative capacity in order to repopulate the bronchiolar wall.
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Affiliation(s)
- Teresa I Fortoul
- Departamento de Biología Celular y Tisular, Facultad de Medicina, Nacional University of Mexico (UNAM), CP 04510 Mexico City, Mexico
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