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Du Q, Chen H, Shi Z, Zhou H. Case Report: Long segmental lesions of the spinal cord caused by exposure to xylene. Front Neurol 2023; 14:1121421. [PMID: 37396768 PMCID: PMC10313390 DOI: 10.3389/fneur.2023.1121421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Accepted: 05/23/2023] [Indexed: 07/04/2023] Open
Abstract
Xylene has the potential to cause nervous system disturbances since it is a lipophilic substance with high affinity for lipid-rich tissue, such as the brain. Involvement in the spinal cord, especially long segmental spinal cord lesions that permeate almost the entire cervical and thoracic spinal cord, is extremely rare. We report two cases of occupational exposure to excessive xylene, both of which presented with severe and rapidly progressive numbness and weakness in the limbs that, more importantly, led to poor outcomes: one died and the other was left severely disabled. In both, spinal magnetic resonance imaging showed long segmental lesions in the cervicothoracic spinal cord. These findings may provide some insights into the effects of xylene as an isolated agent on the spinal cord injury.
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2
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Jeong MH, Han Y, Oh IS, Kim DM, Son DW, Jung MS, Yang H, Lee K, Shin JY, Kim HR, Chung KH. Pre-validation of a Calu-3 epithelium cytotoxicity assay for predicting acute inhalation toxicity of chemicals. Toxicol In Vitro 2021; 75:105136. [PMID: 33675894 DOI: 10.1016/j.tiv.2021.105136] [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: 09/11/2020] [Revised: 02/25/2021] [Accepted: 03/01/2021] [Indexed: 10/22/2022]
Abstract
Although in vivo inhalation toxicity tests have been widely conducted, the testing of many chemicals is limited for economic and ethical reasons. Therefore, we previously developed an in vitro acute inhalation toxicity test method. The goal of the present pre-validation study was to evaluate the transferability, reproducibility, and predictive capacity of this method. After confirming the transferability of the Calu-3 epithelium cytotoxicity assay, reproducibility was evaluated using 20 test substances at three independent institutions. Cytotoxicity data were analyzed using statistical methods, including the intra-class correlation coefficient and Bland-Altman plots for within- and between-laboratory reproducibility. The assay for the 20 test substances showed excellent agreement within and between laboratories. To evaluate the predictive capacity, 77 test substances were analyzed for acute inhalation toxicity. Accuracy was measured using a cutoff of 40%, and the relevance was analyzed as a receiver-operating characteristic (ROC) curve. An accuracy of 72.73% was obtained, and the area under the ROC curve was 0.77, indicating moderate performance. In this study, we found that the in vitro acute inhalation toxicity test method demonstrated good reliability and relevance for predicting the acute toxicity of inhalable chemicals. Hence, this assay has potential as an alternative test for screening acutely toxic inhalants.
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Affiliation(s)
- Mi Ho Jeong
- School of Pharmacy, Sungkyunkwan University, Suwon, Gyeonggi-do 16419, Republic of Korea
| | - Yubin Han
- School of Pharmacy, Sungkyunkwan University, Suwon, Gyeonggi-do 16419, Republic of Korea
| | - In-Sun Oh
- School of Pharmacy, Sungkyunkwan University, Suwon, Gyeonggi-do 16419, Republic of Korea
| | - Dong Min Kim
- School of Pharmacy, Sungkyunkwan University, Suwon, Gyeonggi-do 16419, Republic of Korea
| | - Dong-Won Son
- Biotoxtech, 53, Cheongju, Chungcheongbuk-do 28115, Republic of Korea
| | - Mi-Sook Jung
- Biotoxtech, 53, Cheongju, Chungcheongbuk-do 28115, Republic of Korea
| | - Hyoseon Yang
- National Center for Efficacy Evaluation of Respiratory Disease Product, Korea Institute of Toxicology, Jeongeup 56212, Republic of Korea
| | - Kyuhong Lee
- National Center for Efficacy Evaluation of Respiratory Disease Product, Korea Institute of Toxicology, Jeongeup 56212, Republic of Korea
| | - Ju-Young Shin
- School of Pharmacy, Sungkyunkwan University, Suwon, Gyeonggi-do 16419, Republic of Korea
| | - Ha Ryong Kim
- College of Pharmacy, Daegu Catholic University, Gyeongsan, Gyeongsangbuk-do 38430, Republic of Korea.
| | - Kyu Hyuck Chung
- School of Pharmacy, Sungkyunkwan University, Suwon, Gyeonggi-do 16419, Republic of Korea.
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3
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Gospavic R, Knoll P, Mirzaei S, Popov V. Physiologically Based Pharmacokinetic (PBPK) Model for Biodistribution of Radiolabeled Peptides in Patients with Neuroendocrine Tumours. ASIA OCEANIA JOURNAL OF NUCLEAR MEDICINE & BIOLOGY 2016; 4:90-7. [PMID: 27408897 PMCID: PMC4938879 DOI: 10.7508/aojnmb.2016.02.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Objective(s): The objectives of this work was to assess the benefits of the application of Physiologically Based Pharmacokinetic (PBPK) models in patients with different neuroendocrine tumours (NET) who were treated with Lu-177 DOTATATE. The model utilises clinical data on biodistribution of radiolabeled peptides (RLPs) obtained by whole body scintigraphy (WBS) of the patients. Methods: The blood flow restricted (perfusion rate limited) type of the PBPK model for biodistribution of radiolabeled peptides (RLPs) in individual human organs is based on the multi-compartment approach, which takes into account the main physiological processes in the organism: absorption, distribution, metabolism and excretion (ADME). The approach calibrates the PBPK model for each patient in order to increase the accuracy of the dose estimation. Datasets obtained using WBS in four patients have been used to obtain the unknown model parameters. The scintigraphic data were acquired using a double head gamma camera in patients with different neuroendocrine tumours who were treated with Lu-177 DOTATATE. The activity administered to each patient was 7400 MBq. Results: Satisfactory agreement of the model predictions with the data obtained from the WBS for each patient has been achieved. Conclusion: The study indicates that the PBPK model can be used for more accurate calculation of biodistribution and absorbed doses in patients. This approach is the first attempt of utilizing scintigraphic data in PBPK models, which was obtained during Lu-177 peptide therapy of patients with NET.
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Affiliation(s)
- Radovan Gospavic
- Ascend Technologies Ltd, Eastleigh, UK; Faculty of Civil Engineering, University of Belgrade, Belgrade, Serbia
| | - Peter Knoll
- Institute of Nuclear Medicine with PET-Center, Wilhelminenspital, Vienna, Austria
| | - Siroos Mirzaei
- Institute of Nuclear Medicine with PET-Center, Wilhelminenspital, Vienna, Austria
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Niaz K, Bahadar H, Maqbool F, Abdollahi M. A review of environmental and occupational exposure to xylene and its health concerns. EXCLI JOURNAL 2016. [PMID: 26862322 DOI: 10.17179/excli2015-623,2015-623] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Xylene is a cyclic hydrocarbon, and an environmental pollutant. It is also used in dyes, paints, polishes, medical technology and different industries as a solvent. Xylene easily vaporizes and divides by sunlight into other harmless chemicals. The aim of the present review is to collect the evidence of the xylene toxicity, related to non-cancerous health hazards, as well as to provide possible effective measurement to minimize its risk ratio. For current study a bibliographic search of more than 250 peer-reviewed papers in scientific data including PubMed, and Google Scholar about xylene was done. But approximately 130 peer-reviewed papers relevant to xylene were included (Figure 1(Fig. 1)). All scientific data was reviewed with key words of "xylene toxicity", "xylene toxic health effects", "environmental volatile organic compounds", "human exposure to xylene", "xylene poisoning in laboratory workers", "effects of xylene along with other hydrocarbons", "neurotoxicity of selected hydrocarbons", and "toxic effects of particular xylene isomers in animals". According to these studies, xylene is released into the atmosphere as fugitive emissions from petrochemical industries, fire, cigarette, from different vehicles. Short term exposure to mixed xylene or their individual isomers result in irritation of the nose, eyes and throat subsequently leading toward neurological, gastrointestinal and reproductive harmful effects. In addition long term exposure to xylene may cause hazardous effects on respiratory system, central nervous system, cardiovascular system, and renal system. The health concerns of xylene are well documented in animals and human. It is important to improve health policies, launch xylene related health and toxicity awareness campaigns, to get rid of its dangerous outcomes. Chronic diseases have become a threat to human globally, with special prominence in regions, where xylene is used with other chemicals (benzene, toluene etc.) especially in petroleum and rubber industry. The mechanism of toxicity and interactions with endocrine system should be followed up which is the main threat to human health.
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Affiliation(s)
- Kamal Niaz
- Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, International Campus, Tehran, Iran
| | - Haji Bahadar
- Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, International Campus, Tehran, Iran
| | - Faheem Maqbool
- Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, International Campus, Tehran, Iran
| | - Mohammad Abdollahi
- Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, International Campus, Tehran, Iran; Department of Toxicology and Pharmacology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran 1417614411, Iran
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5
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Chen N, Deng D, Li Y, Xing X, Liu X, Xiao X, Wang Y. The xylene sensing performance of WO3 decorated anatase TiO2 nanoparticles as a sensing material for a gas sensor at a low operating temperature. RSC Adv 2016. [DOI: 10.1039/c6ra09195d] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Here, the pristine and WO3 decorated TiO2 nanoparticles were synthesized by a one-step hydrothermal without the use of a surfactant or template, and used to fabricate gas sensors.
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Affiliation(s)
- Nan Chen
- Department of Physics
- Yunnan University
- Kunming
- People's Republic of China
| | - Dongyang Deng
- School of Materials Science and Engineering
- Yunnan University
- Kunming
- People's Republic of China
| | - Yuxiu Li
- School of Materials Science and Engineering
- Yunnan University
- Kunming
- People's Republic of China
| | - Xinxin Xing
- School of Materials Science and Engineering
- Yunnan University
- Kunming
- People's Republic of China
| | - Xu Liu
- School of Materials Science and Engineering
- Yunnan University
- Kunming
- People's Republic of China
| | - Xuechun Xiao
- School of Materials Science and Engineering
- Yunnan University
- Kunming
- People's Republic of China
- Yunnan Province Key Lab of Micro-Nano Materials and Technology
| | - Yude Wang
- Department of Physics
- Yunnan University
- Kunming
- People's Republic of China
- Yunnan Province Key Lab of Micro-Nano Materials and Technology
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6
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Niaz K, Bahadar H, Maqbool F, Abdollahi M. A review of environmental and occupational exposure to xylene and its health concerns. EXCLI JOURNAL 2015; 14:1167-86. [PMID: 26862322 PMCID: PMC4743476 DOI: 10.17179/excli2015-623] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 10/31/2015] [Indexed: 11/17/2022]
Abstract
Xylene is a cyclic hydrocarbon, and an environmental pollutant. It is also used in dyes, paints, polishes, medical technology and different industries as a solvent. Xylene easily vaporizes and divides by sunlight into other harmless chemicals. The aim of the present review is to collect the evidence of the xylene toxicity, related to non-cancerous health hazards, as well as to provide possible effective measurement to minimize its risk ratio. For current study a bibliographic search of more than 250 peer-reviewed papers in scientific data including PubMed, and Google Scholar about xylene was done. But approximately 130 peer-reviewed papers relevant to xylene were included (Figure 1(Fig. 1)). All scientific data was reviewed with key words of "xylene toxicity", "xylene toxic health effects", "environmental volatile organic compounds", "human exposure to xylene", "xylene poisoning in laboratory workers", "effects of xylene along with other hydrocarbons", "neurotoxicity of selected hydrocarbons", and "toxic effects of particular xylene isomers in animals". According to these studies, xylene is released into the atmosphere as fugitive emissions from petrochemical industries, fire, cigarette, from different vehicles. Short term exposure to mixed xylene or their individual isomers result in irritation of the nose, eyes and throat subsequently leading toward neurological, gastrointestinal and reproductive harmful effects. In addition long term exposure to xylene may cause hazardous effects on respiratory system, central nervous system, cardiovascular system, and renal system. The health concerns of xylene are well documented in animals and human. It is important to improve health policies, launch xylene related health and toxicity awareness campaigns, to get rid of its dangerous outcomes. Chronic diseases have become a threat to human globally, with special prominence in regions, where xylene is used with other chemicals (benzene, toluene etc.) especially in petroleum and rubber industry. The mechanism of toxicity and interactions with endocrine system should be followed up which is the main threat to human health.
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Affiliation(s)
- Kamal Niaz
- Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, International Campus, Tehran, Iran
| | - Haji Bahadar
- Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, International Campus, Tehran, Iran
| | - Faheem Maqbool
- Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, International Campus, Tehran, Iran
| | - Mohammad Abdollahi
- Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, International Campus, Tehran, Iran
- Department of Toxicology and Pharmacology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran 1417614411, Iran
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7
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Richtwerte für Dimethylbenzole in der Innenraumluft. Bundesgesundheitsblatt Gesundheitsforschung Gesundheitsschutz 2015; 58:1378-89. [DOI: 10.1007/s00103-015-2252-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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8
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Jamalzadeh S, Haghighi M, Asgari N. Synthesis and physicochemical characterizations of nanostructured Pd/carbon-clinoptilolite-CeO2 catalyst for abatement of xylene from waste gas streams at low temperature. J IND ENG CHEM 2014. [DOI: 10.1016/j.jiec.2013.11.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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9
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Huizer D, Huijbregts MA, van Rooij JG, Ragas AM. Testing the coherence between occupational exposure limits for inhalation and their biological limit values with a generalized PBPK-model: The case of 2-propanol and acetone. Regul Toxicol Pharmacol 2014; 69:408-15. [DOI: 10.1016/j.yrtph.2014.05.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 05/10/2014] [Accepted: 05/12/2014] [Indexed: 10/25/2022]
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10
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Chambers DM, Ocariz JM, McGuirk MF, Blount BC. Impact of cigarette smoking on volatile organic compound (VOC) blood levels in the U.S. population: NHANES 2003-2004. ENVIRONMENT INTERNATIONAL 2011; 37:1321-1328. [PMID: 21703688 DOI: 10.1016/j.envint.2011.05.016] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Revised: 04/15/2011] [Accepted: 05/25/2011] [Indexed: 05/26/2023]
Abstract
The impact of cigarette smoking on volatile organic compound (VOC) blood levels is studied using 2003-2004 National Health and Nutrition Examination Survey (NHANES) data. Cigarette smoke exposure is shown to be a predominant source of benzene, toluene, ethylbenzene, xylenes and styrene (BTEXS) measured in blood as determined by (1) differences in central tendency and interquartile VOC blood levels between daily smokers [≥1 cigarette per day (CPD)] and less-than-daily smokers, (2) correlation among BTEXS and the 2,5-dimethylfuran (2,5-DMF) smoking biomarker in the blood of daily smokers, and (3) regression modeling of BTEXS blood levels versus categorized CPD. Smoking status was determined by 2,5-DMF blood level using a cutpoint of 0.014 ng/ml estimated by regression modeling of the weighted data and confirmed with receiver operator curve (ROC) analysis. The BTEXS blood levels among daily smokers were moderately-to-strongly correlated with 2,5-DMF blood levels (correlation coefficient, r, ranging from 0.46 to 0.92). Linear regression of the geometric mean BTEXS blood levels versus categorized CPD showed clear dose-response relationship (correlation of determination, R(2), ranging from 0.81 to 0.98). Furthermore, the pattern of VOCs in blood of smokers is similar to that reported in mainstream cigarette smoke. These results show that cigarette smoking is a primary source of benzene, toluene and styrene and an important source of ethylbenzene and xylene exposure for the U.S. population, as well as the necessity of determining smoking status and factors affecting dose (e.g., CPD, time since last cigarette) in assessments involving BTEXS exposure.
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Affiliation(s)
- David M Chambers
- Centers for Disease Control and Prevention, National Center for Environmental Health, Atlanta, GA 30341, United States.
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11
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Su FC, Mukherjee B, Batterman S. Trends of VOC exposures among a nationally representative sample: Analysis of the NHANES 1988 through 2004 data sets. ATMOSPHERIC ENVIRONMENT (OXFORD, ENGLAND : 1994) 2011; 45:4858-4867. [PMID: 25705111 PMCID: PMC4335682 DOI: 10.1016/j.atmosenv.2011.06.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Exposures to volatile organic compounds (VOCs) are ubiquitous due to emissions from personal, commercial and industrial products, but quantitative and representative information regarding long term exposure trends is lacking. This study characterizes trends from1988 to 2004 for the 15 VOCs measured in blood in five cohorts of the National Health and Nutrition Examination Survey (NHANES), a large and representative sample of U.S. adults. Trends were evaluated at various percentiles using linear quantile regression (QR) models, which were adjusted for solvent-related occupations and cotinine levels. Most VOCs showed decreasing trends at all quantiles, e.g., median exposures declined by 2.5 (m, p-xylene) to 6.4 (tetrachloroethene) percent per year over the 15 year period. Trends varied by VOC and quantile, and were grouped into three patterns: similar decreases at all quantiles (including benzene, toluene); most rapid decreases at upper quantiles (ethylbenzene, m, p-xylene, o-xylene, styrene, chloroform, tetrachloroethene); and fastest declines at central quantiles (1,4-dichlorobenzene). These patterns reflect changes in exposure sources, e.g., upper-percentile exposures may result mostly from occupational exposure, while lower percentile exposures arise from general environmental sources. Both VOC emissions aggregated at the national level and VOC concentrations measured in ambient air also have declined substantially over the study period and are supportive of the exposure trends, although the NHANES data suggest the importance of indoor sources and personal activities on VOC exposures. While piecewise QR models suggest that exposures of several VOCs decreased little or any during the 1990's, followed by more rapid decreases from 1999 to 2004, questions are raised concerning the reliability of VOC data in several of the NHANES cohorts and its applicability as an exposure indicator, as demonstrated by the modest correlation between VOC levels in blood and personal air collected in the 1999/2000 cohort. Despite some limitations, the NHANES data provides a unique, long term and direct measurement of VOC exposures and trends.
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Affiliation(s)
- Feng-Chiao Su
- Environmental Health Sciences, School of Public Health, University of Michigan, MI, USA
| | - Bhramar Mukherjee
- Biostatistics, School of Public Health, University of Michigan, MI, USA
| | - Stuart Batterman
- Environmental Health Sciences, School of Public Health, University of Michigan, MI, USA
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Yoshida T. Estimation of absorption of aromatic hydrocarbons diffusing from interior materials in automobile cabins by inhalation toxicokinetic analysis in rats. J Appl Toxicol 2011; 30:525-35. [PMID: 20809541 DOI: 10.1002/jat.1522] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Aromatic hydrocarbons, as well as aliphatic hydrocarbons, diffusing from interior materials in automotive cabins are the most common compounds contributing to interior air pollution. In this study, the amounts of seven selected aromatic hydrocarbons absorbed by a car driver were estimated by evaluating their inhalation toxicokinetics in rats. Measured amounts of these substances were injected into a closed chamber system containing a rat, and the concentration changes in the chamber were examined. The toxicokinetics of the substances were evaluated on the basis of the concentration-time course using a nonlinear compartment model. The amounts absorbed in humans at actual concentrations in automobile cabins without ventilation were extrapolated from the results obtained from rats. The absorbed amounts estimated for a driver during a 2 h drive were as follows (per 60 kg of human body weight): 30 microg for toluene (interior median concentration, 40 microg m(-3) in our previous study), 10 microg for ethylbenzene (12 microg m(-3)), 6 microg for o-xylene (10 microg m(-3)), 8 microg for m-xylene (11 microg m(-3)), 9 microg for p-xylene (11 microg m(-3)), 11 microg for styrene (11 microg m(-3)) and 27 microg for 1,2,4-trimethylbenzene (24 microg m(-3)). Similarly, in a cabin where air pollution was marked, the absorbed amount of styrene (654 microg for 2 h in a cabin with an interior maximum concentration of 675 microg m(-3)) was estimated to be much higher than those of other substances. This amount (654 microg) was approximately 1.5 times the tolerable daily intake of styrene (7.7 microg kg(-1) per day) recommended by the World Health Organization.
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Affiliation(s)
- Toshiaki Yoshida
- Osaka Prefectural Institute of Public Health, 1-3-69, Nakamichi, Higashinari-ku, Osaka 537-0025, Japan.
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Aylward LL, Kirman CR, Blount BC, Hays SM. Chemical-specific screening criteria for interpretation of biomonitoring data for volatile organic compounds (VOCs)--application of steady-state PBPK model solutions. Regul Toxicol Pharmacol 2010; 58:33-44. [PMID: 20685286 DOI: 10.1016/j.yrtph.2010.05.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Revised: 05/20/2010] [Accepted: 05/21/2010] [Indexed: 12/16/2022]
Abstract
The National Health and Nutrition Examination Survey (NHANES) generates population-representative biomonitoring data for many chemicals including volatile organic compounds (VOCs) in blood. However, no health or risk-based screening values are available to evaluate these data from a health safety perspective or to use in prioritizing among chemicals for possible risk management actions. We gathered existing risk assessment-based chronic exposure reference values such as reference doses (RfDs), reference concentrations (RfCs), tolerable daily intakes (TDIs), cancer slope factors, etc. and key pharmacokinetic model parameters for 47 VOCs. Using steady-state solutions to a generic physiologically-based pharmacokinetic (PBPK) model structure, we estimated chemical-specific steady-state venous blood concentrations across chemicals associated with unit oral and inhalation exposure rates and with chronic exposure at the identified exposure reference values. The geometric means of the slopes relating modeled steady-state blood concentrations to steady-state exposure to a unit oral dose or unit inhalation concentration among 38 compounds with available pharmacokinetic parameters were 12.0 microg/L per mg/kg-d (geometric standard deviation [GSD] of 3.2) and 3.2 microg/L per mg/m(3) (GSD=1.7), respectively. Chemical-specific blood concentration screening values based on non-cancer reference values for both oral and inhalation exposure range from 0.0005 to 100 microg/L; blood concentrations associated with cancer risk-specific doses at the 1E-05 risk level ranged from 5E-06 to 6E-02 microg/L. The distribution of modeled steady-state blood concentrations associated with unit exposure levels across VOCs may provide a basis for estimating blood concentration screening values for VOCs that lack chemical-specific pharmacokinetic data. The screening blood concentrations presented here provide a tool for risk assessment-based evaluation of population biomonitoring data for VOCs and are most appropriately applied to central tendency estimates for such datasets.
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Clewell HJ, Tan YM, Campbell JL, Andersen ME. Quantitative Interpretation of Human Biomonitoring Data. Toxicol Appl Pharmacol 2008; 231:122-33. [DOI: 10.1016/j.taap.2008.04.021] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2008] [Revised: 04/19/2008] [Accepted: 04/28/2008] [Indexed: 10/22/2022]
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Abstract
INTRODUCTION Most human environments are characterised by the presence of a large number of chemical substances which belong, for the most part, to the group of volatile organic compounds (VOC). BACKGROUND The first epidemiological transverse studies have revealed that respiratory symptoms could be related to high domestic exposure to VOC. More recently, the results of longitudinal studies have suggested a possible influence of VOC exposure on the immune status of the newborn child after maternal exposure, the enhancement of sensitisation and the risk of asthma or respiratory symptoms. VIEWPOINT AND CONCLUSIONS Further studies are needed to understand the mechanisms underlying the health effects of VOC. These should rely on greater knowledge of the individual exposure concentrations of these compounds and their sources. Proposals to improve the indoor environment could be made to reduce exposure and prevent the health effects of VOC.
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