Health Risk Assessment Of Workers Research Articles

Optimization of benzene exposure risk assessment: An integrated approach utilizing internal and external concentrations with a focus on biomarkers S-PMA & t, t-MA

In the majority of occupational settings within China, the concentrations of benzene are observed to fall markedly below the demarcated detection thresholds. Employing traditional risk assessment models, the presence of exceptionally low airborne benzene exposure concentrations may infuse heightened degrees of uncertainty. Consequently, the necessity arises to investigate risk assessment methodologies more apt for the prevalent exposure environment among employees. In the present study, a pharmacokinetic model premised on urinary benzene metabolites (S-PMA and t, t-MA) was employed to ascertain a more precise daily airborne benzene exposure concentration per individual. This value was integrated into the linear multistage model as the ‘internal exposure concentration’. In conjunction with the U.S National Environmental Protection Agency's (EPA) inhalation risk assessment model predicated on the external exposure concentration, the Singapore Ministry of Manpower's (MOM) model, and the linear multistage (LMS) model, the carcinogenic and non-carcinogenic effects of benzene were evaluated for 1781 benzene-exposed employees across 76 enterprises in Jiangsu Province. Findings suggest that in the linear multilevel model assessment, the cancer risk levels based on t, t-MA and S-PMA were higher in the printing and recording media reproduction industry, automobile manufacturing industry, general equipment manufacturing industry and the furniture manufacturing industry (median 2.842 × 10−4, 2.819 × 10−4, 2.809 × 10−4, and 2.678 × 10−4), which align more consistently with the actual benzene exposure circumstances of each industry's study participants, with overall risk levels calculated by the linear multistage model exceeding those of the EPA inhalation risk assessment model and the MOM model. This implies that the linear multistage model of internal exposure, based on the reciprocal of benzene biomarkers S-PMA and t, t-MA for airborne benzene exposure, presents enhanced sensitivity and suitability for the current occupational health risk assessment of workers. Without doubt, biomarker-based benzene exposure risk assessment emerges as the optimal choice.

Health risk assessment of workers' exposure to BTEX and PM during refueling in an urban fuel station.

The proximity of fuel stations to the roads and the activities inside the station can contribute to PM and VOCs and impose health risks on station workers. The study presents the exposure and health risk assessment of the fuel station personnel to total volatile organic compounds (TVOCs) and particulate matter (PM) during refueling operations. TVOCs and PM monitoring were carried out at a fuel station in Chennai, India, for 1 week in March 2021, covering both weekdays and weekends. The health risks were assessed using EPA's health impact assessment methodology. Exposure to TVOCs (3177.39 ± 5450.32 μg/m3) exceeded the EPA standard of 5 μg/m3, by more than 500 times, peaking during refueling operations. The average concentrations of PM10, PM2.5, and PM1 were 76.55 ± 23.08 μg/m3, 41.81 ± 9 μg/m3, and 30.38 ± 7.56 μg/m3, respectively. The concentrations were observed to be high during morning and evening hours due to the increased traffic on the adjacent road and inside the fuel station. The synergistic health risks linked with long-term exposure to high concentrations of BTEX and PM were also estimated. At the fuel station, a significant contribution to the SOA formation potential was shown by toluene, followed by m-xylene, p-xylene, o-xylene, ethylbenzene, and benzene. Furthermore, the deposition of airborne particles in the workers' respiratory tract was calculated using the Multiple Path Particle Dosimetry model while considering the daily average exposure duration of 12 h. The results showed that 59% of PM10 particles were deposited in the head region, whereas 11% and 10% of PM2.5 and PM1 particles were deposited in the pulmonary region. Hence, the health risk assessment indicated no non-cancer risk of exposure to PM (hazard quotient = 0.13) to station personnel exposed regularly for 1 year. However, prolonged exposure to VOCs for more than 1 year can result in both carcinogenic and non-carcinogenic risk (hazard quotient = 0.045 and cancer risk > 10-6) in workers.

Health risk assessment of workers exposed to lead dust in informal e-waste recycling workshops

ABSTRACT Informal recycling of electronic waste (e-waste) has attracted significant attention due to its economic benefits and rapid growth rate in many parts of the world. Unfortunately, unsafe conditions of recycling workshops possess chronic exposure to workers and lead to elevated blood lead concentrations (BLCs). Upon measuring the lead concentration in the dust of recycling workshops and the e-wastes in southwestern region of Iran, the related health risks were assessed in 30 exposed workers and 30 non-exposed habitants cases based on the determination of BLC. The average BLCs in exposed workers and non-exposed habitants cases were 24 μg/dL and 7 μg/dL, respectively. The geo-accumulation index (Igeo) revealed heavy contamination of dust in informal e-waste recycling workshops (IERWs) (5023 μg/kg) and significantly lower levels in unexposed areas (49 μg/kg). Health risk assessment indicated that lead exposure from IERWs appears to be a potential threat to workers and indirectly to their families.

Use of Biomonitoring in Health Risk Assessment of Workers to Heavy Metals in Industrial Environment

The problem of occupational and work exposure to trace and toxic metals existed at the beginning of industrialization which even persists today. Biomonitoring is the analytical science with multidisciplinary applications that guides industrialist in assessment, management and prevention of trace and toxic metal exposure to workers at workplace. In the present research work, 40 workers were included for the study as subjects out of which, 20 were exposed and 20 were included as controls. Head hair samples were collected from all the subjects and were pretreated for decontamination by wash-ing then digested to get colourless solution prior to analysis for lead (Pb) and cadmium (Cd) with an Atomic Absorption Spectrophotometer.

Machine learning assessment of white blood cell counts in workers exposed to benzene: a historical cohort study.

To explore the fitting effect of the ARIMA, GM(1,1), and RANSAC model in the changes of white blood cells (WBC) in benzene-exposed workers, and select the optimal model to predict the WBC count of workers. Among 350 employees in an aerospace process manufacturing enterprise in Nanjing, workers with 10years of benzene exposure were selected, and used Excel software to organize the WBC data, and the ARIMA model and RANSAC model were established by R software, and the GM(1, 1) model was established by DPS software, and the magnitude of the mean absolute percentage error (MAPE) of fitting three models to WBC counts was compared. The MAPE based on the ARIMA(2,1,2) model is 6.78%, the MAPE based on the GM(1,1) model is 5.19%, and the MAPE based on the RANSAC model is 6.37%, so the GM( 1,1) model was more suitable for fitting the trend of WBC counts in benzene exposed workers in this study. The GM(1,1) model is suitable for fitting WBC counts in a small sample size and can provide a short-term prediction of WBC counts in benzene-exposed workers and provide basic information for occupational health risk assessment of workers.

Health Risk Assessment for Pest Control Workers Using Biocidal Products after COVID-19 Outbreak: A Comparison of EU and US

After the COVID-19 outbreak, the workloads of disinfection have remarkably increased. As disinfectants are harmful to human, health risk assessment of disinfection workers is needed to ensure their safety. However, the acceptable operator exposure level (AOEL) for most disinfectants are not established. Moreover, the method of calculating the AOEL varies across the countries. This study aims to identify the health risks of disinfection workers based on two different risk assessment methods of EU and US after the COVID-19 outbreak. We surveyed 533 disinfection workers to identify exposure patterns of disinfectants. The inhalation and dermal exposure were calculated based on different work types. The AOEL was calculated and compared using the EU and US methods. The health risks of workers are determined by hazard index based on whether the exposure exceeds AOEL. Workers used 53 chemicals from 175 biocidal products, and only 34 chemicals (65%) had AOEL. 17 Chemicals with absorption factors for each route or AOEL were selected for risk assessment. When compared the estimated AOEL was calusing EU and US methods, only 2 (4%) were the same. The result of health risk assessment showed 10 (19%) were exceed 1 (acceptable level) using EU method, while 9 (17%) were exceed 1 using US method. This study performed the health risk assessment of disinfection workers based on EU and US methods after the COVID-19 outbreak. Only 65% had an AOEL, and health risks of workers were differd according to risk calculation methods of EU and US. Given the increasing use of biocides after the COVID-19 outbreak, AOEL need to be established for health risk assessment of workers. Biocides, Risk assessment, Reference dose, AOEL, COVID-19, pest control worker This study was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2021R1F1A1063967).

Integrated model of health risk assessment for workers having to work outdoors under exposure to cooling meteorological factors

Natural resources extraction involves continuous exposure to cooling meteorological factors typical for open production grounds. This necessitates relevant health risk assessment and management of health risks caused by exposure to these harmful occupational factors. However, the available risk assessment models do not provide a possibility to perform complete assessment of the existing risks created by exposure to meteorological hazards. The study design included the following. We performed hygienic assessment of working conditions and health of workers employed by “Samotlorneftegaz” Joint Stock Company (JSC) who had to perform their work tasks under exposure to cooling meteorological factors on open production grounds; the assessment involved calculating the group health risk. Individual peculiarities were assessed using subjective (547 people took part in questioning) and objective assessment methods (76 people took part in estimating thermal state of their bodies and 54 people participated in thermometry with cold stress). Finally, we assessed prior and posterior risks. The prior group risk assessment made it possible to identify risk groups who had a significant risk of developing occupational and non-occupational diseases and to rank working places as per health hazards. The posterior risk assessment confirmed the results produced by the prior risk assessment regarding potentiating negative effects produced by cooling meteorological factors. The assessment of developing general and local thermoregulation disorders revealed that certain individual peculiarities made a substantial contribution into their development. Among them, we can mention long-term outdoor work (60 % of work time or more) under exposure to cooling meteorological factors; a chronic pathology; tobacco smoking. The results produced by this study allowed us to suggest an integrated model for risk assessment, management and communication about health risks caused by working under exposure to cooling meteorological factors.

Application of five methods in the occupational health risk assessment of workers exposed to welding fumes

Objective: To assess the health risks of welding fume jobs with five occupational health risk assessment methods, and to compare the advantages, disadvantages and applicability of these methods in the health risk assessment of welding fume. Methods: The International Commission for Mining and Metals (ICMM) occupational health risk assessment method, MES method, the qualitative method and comprehensive index method in GBZ/T 298-2017 "Technical Guidelines for Occupational Health Risk Assessment of Chemical Hazardous Factors in the Workplace" were used to assess the risk of welding fume exposure positions in four manufacturing enterprises in Tianjin in March, 2020. The assessment results of different methods were standardized by risk ratio (RR) . Results: After the results were standardized, the results of enterprises 1, 2 and 4 were negligible risks, enterprise 3 was medium risk in the ICMM matrix method and MES method, and the results of ICMM quantitative method for each enterprise were negligible risk, low risk, extremely high risk and low risk, respectively. The results of the qualitative assessment of the guidelines for all companies were negligible risks, and the comprehensive index method were medium risks. Conclusion: The five models are all suitable for occupational health risk assessment of welding fumes, but they all have certain shortcomings. They should be combined with qualitative and semi-quantitative assessment results for comprehensive analysis.

Effect of welding operations on the health status of workers with low working age

Objective To explore the impact of welding operations on the health status of workers with low working age, and provide a basis for occupational health risk assessment for workers of low working age. Methods Used the method of cluster sampling to randomly selected workers from an automobile manufacturing plant in Guangzhou as research subjects: 982 workers with welding posts of 1 year ≤working age ≤5 years were welding groups, 707 workers with simple exposure noise of 1 year ≤working age ≤5 years were assembly groups, and 717 workers in pre-job medical examinations were pre-job groups from June 2017 to September 2018. Then conducted occupational health checks on all subjects, investigated and detected the occupational hazards in welding posts and assembly posts. Results There was no statistical difference between the noise over-standard rate of welding posts' (59.3%, 16/27) and the assembly posts' (47.4%, 9/19) (P>0.05) . The over-standard rate of welding fume, manganese and its inorganic compounds in welding posts was 11.11% (3/27) . The results of occupational health examination showed that the detection rate of disease or abnormal of the welding group was 78.4% (770/982) higher than 70.2% (496/707) in the assembly group and 53.0% (380/717) in the pre-job group (the value of 2 were 14.92 and 122.37, respectively, P<0.05) . The rate of hearing loss of the assembly group and the welding group were 14.7% (104/707) and 19.3% (190/982) , respectively, which was higher than that of the pre-job group (10.5%, 75/717) , and the hearing loss rate gradually increased with the increase of working age (the value of linear-by-linear association were 12.04 and 44.67, respectively, P<0.01) . Compared with the hearing loss rate of each working age of the assembly group, the hearing loss rate of each working age of the welding group was higher, and when the working age was 3 years, the risk of hearing loss in the welding group was 2.70 times that of the assembly group (P<0.01) . The rate of pulmonary dysfunction in the welding group was 19.2% (189/982) higher than that in the pre-job group (12.6%, 90/717) , and it increased with the increase of working age (the value of linear-by-linear association was 15.97, P<0.01) . Conclusion Welding work seriously damages the health of workers with low working age, increases the hearing loss of workers and the occurrence of pulmonary dysfunction; manganese and its compounds increases noise-induced damage to the hearing system. Key words: Welding fume; Manganese and its compounds; Low working age; Hearing loss; Pulmonary ventilation dysfunction

An Environmental Health Risk Assessment of Workers’ Ambient Exposure to Particulate Matter of 2.5 Microns or Less at a Concrete Batching Plant

An Environmental Health Risk Assessment of Workers’ Ambient Exposure to Particulate Matter of 2.5 Microns or Less at a Concrete Batching Plant

THE HYGIENIC ASSESSMENT OF THE WORKING ENVIRONMENT IN INDIVIDUAL OCCUPATIONS IN BUILDING ORGANIZATIONS

Introduction. The development of the construction industry is accompanied by the use of new technologies and building materials. Materials based on mineral wool (MW) became to be widely used. The article presents the results of the study of working environment factors and the determination of the safe for health work experience based on the health risk calculation for workers in contact with MW. Material and methods. To quantify the air pollution of the working area at the construction site, samples were taken using an aspirator and a dust meter. An absorption method using a spectrophotometer was used to determine the chemical composition of the dust. Statistical analysis and mathematical modeling were carried out using a standard software package Microsoft Excel, STADIA. Results. A table for the rapid health risk assessment of workers in contact with MW was developed. The risk of health loss is determined as “High” (R = 11.3). Discussion. Working conditions under the performance of heat-insulating works at facades cladding with the use of MW are classified as harmful (class 3.2) on the dust content in working zone air. In the course of the study, coarse dust and fine dust were found in the air. The data on the change of the dust concentration depending on air humidity, the concentration of dust particles of different dispersion at different distances from the place of work is presented. The chemical composition of dust is presented, the presence of heavy metals is established. Dependences for the determination of safe for health work experience under the influence of the various concentration of dust and the duration of contact are constructed. Сonclusions. On the basis of the research to improve the legal support in the field of occupational health and safety, a number of activities for workers engaged in work with the use of MW are proposed.

Indoor air quality and health risk assessment for workers in packaging production factory, Can Tho city, Viet Nam

The production of packaging goods for cement is one of the most important industries, contributing to income of many workers. Production activities, however, cause air pollution and health risk. The study was conducted to assess air quality and health risks of workers through air quality data and interviewing employees from 2016-2017 at a packaging production factory, Cantho city, Vietnam. The findings indicated that temperature and noise exceeded the national technical regulations (QCVN 22-26: 2016/TT-BYT) while the humidity, wind speed, light, respirable particles, toxic gases (benzene, toluene, methyl ethyl ketone (MEK)) were in accordance with the national standards for occupational health and safety (Decision 3733/2002/QĐ-BYT). However, health risk assessment showed that long-term exposure in this factory would result in severe impact on health of workers due to indoor air pollution. The non-cancer risk caused by benzene, toluene and MEK for workers in the working sections such as printing, film coating, weaving, spinning and pasting was expected to cause serious impact on workers’ health. The cancer risk (benzene) index was in the range of 1.3 x 10-5 to 7.7 x 10-4 and averaged at 3.3 x 10-4. The study clearly showed that benzene greatly contributes to serious workers’ health effects. Appropriate protection measures such as treatment of air pollutants, regular health check, wearing protective clothes should be implemented to mitigate impact of indoor air pollution at the factory. More importantly, it is necessary to reconsider the standard values of benzene, toluene, methyl ethyl ketone to ensure health of workers.&#x0D; Công nghiệp sản xuất bao bì xi măng thuộc lĩnh vực ngành xây dựng là một trong những ngành công nghiệp quan trọng, đã góp phần mang lại nguồn thu nhập cho nhiều người lao động. Tuy nhiên hoạt động sản xuất cũng gây ra những vấn đề về ô nhiễm môi trường không khí và rủi ro sức khỏe. Nghiên cứu được thực hiện nhằm đánh giá mức độ ô nhiễm môi trường không khí và đánh giá rủi ro sức khỏe của công nhân thông qua số liệu chất lượng môi trường không khí và phỏng vấn trực tiếp người lao động trong khoảng thời gian từ 2016 - 2017. Kết quả nghiên cứu cho thấy nhiệt độ, tiếng ồn vượt qui chuẩn cho phép (QCVN 22-26:2016/TT-BYT) trong khi độ ẩm, tốc độ gió, ánh sáng, bụi hô hấp, hơi khí độc (Benzen, toluen, methyl ethyl ketone) đạt chuẩn cho phép theo tiêu chuẩn vệ sinh an toàn lao động (QĐ 3733/2002/QĐ-BYT). Tuy nhiên, kết quả đánh giá rủi ro sức khỏe cho thấy công nhân làm việc lâu dài sẽ bị ảnh hưởng nghiêm trọng đến sức khỏe do ô nhiễm không khí. Rủi ro không gây ung thư do benzene, toluene và MEK gây ra đối với công nhân ở từng khu vực có thể gây ảnh hưởng nghiêm trọng đến sức khỏe công nhân làm việc ở các khu vực sản xuất như in, tráng màng, dệt, kéo sợi và dán. Benzene gây rủi ro ung thư với xác suất từ 1 đến 7 người trong 10.000 người trong quá trình làm việc lâu dài tại nhà máy. Nghiên cứu cho thấy benzene đóng góp rất lớn vào khả năng gây ảnh hưởng nghiêm trọng đến sức khỏe công nhân. Môi trường không khí bên trong nhà máy cần được cải thiện hơn nữa đồng thời tuyên truyền nâng cao ý thức công nhân thực hiện nghiêm túc bảo hộ lao động, tổ chức khám sức khỏe định kỳ cho công nhân. Quan trọng hơn là cần điều chỉnh lại các giá trị qui chuẩn để đảm bảo an toàn sức khỏe cho công nhân đang làm việc tại những nơi có sự hiện diện của khí độc như benzene, toluen, methyl ethyl ketone.

Health Risk Assessment of Workers at the Mining Company PT. HIJ Site in South Kalimantan: An Overview

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PAHs exposure and occupational health risk assessment of workers in coal tar pitch factory

Objective: To Investigation of industrial sites involving coal tar pitch to detect PAHs in the occupational environment and to assess their occupational health risks to workers. Methods: Taking coal tar pitch enterprises as the research object, and making the occupational health field investigation and inspection. Detecting the 16 PAHs in the samples by high performance liquid chromatography (HPLC) , analyze the PAHs exposed dose of the workers in the place, and using cumulative toxic equivalent quantity method, loss of life expectancy method and carcinogenic risk factor method to assessment worker's occupational health risk. Results: In the 15 posts involved, Some workers' exposed to the total concentration of PAHs is higher than others, the maximum exposure concentration is 1931.45ng/m3. There are different hazard risk levels in different working post due to different processes.The lifetime risk of workers is significantly higher than the acceptable range. Some workers has higher carcinogenic risk and workers' life expectancy loss is up to 1033.95 hours. Conclusion: Part of the coal tar pitch workers exposed to higher concentrations of PAHs, and beyond the occupational exposure limits.And there is a high occupational health risk due to high exposure to PAHs.

에폭시 바닥코팅작업장에서의 페닐 글리시딜 에테르 취급 근로자에 대한 건강 위험성 평가

에폭시 바닥코팅작업장에서의 페닐 글리시딜 에테르 취급 근로자에 대한 건강 위험성 평가

Coking wastewater treatment plant as a source of polycyclic aromatic hydrocarbons (PAHs) to the atmosphere and health-risk assessment for workers

PAHs were identified and some of them were determined in the air around a coking wastewater treatment plant (WWTP) using passive air samplers. Seventy seven PAHs were found in the emissions from the degreasing tanks, the aeration tanks and the secondary clarifiers. ∑PAH concentrations within the plant (373.3±27.3–12959.5±685.9ng/m3) were 3–41 times higher compared to the reference sites (315.7±50.2–363.4±77.5ng/m3). The identification of numerous PAHs and high concentrations of these selected ones in the air of the studied sites indicated that the coking WWTP was a new source of atmospheric PAHs. Variations in the PAH pattern were observed in air within the coking WWTP. For example, Flu and Pyr accounted for 35–46% of the total contents at the degreasing tanks, but less than 10% at the hydrolytic tanks. The calculation of the diagnostic ratios suggested that PAHs in the emissions had the source characters of coal combustion. Furthermore, highly elevated PAH concentrations were determined at the degreasing tanks compared to the other tanks (i.e., aeration tanks and secondary clarifiers) and likely associated with their high concentrations in the coking wastewater and increased volatilization at high water temperature. Health risk assessments were carried out by evaluating the inhalation PAH exposure data. The resultant inhalation exposure levels due to TEQBaP for workers ranged from 1.6±0.6 to 71.2±8.2ng/m3, and the estimated lung cancer risks were between 0.1×10−3±0.1×10−4 and 5.2×10−3±0.5×10−3, indicating PAHs in the air around the degreasing tanks and the aerobic tanks would have potential lung cancer risk for the operating workers.

Bacterial Community Composition of Biological Degreasing Systems and Health Risk Assessment for Workers

Biological degreasing system is a new technology based on the degradation capabilities of microorganisms to remove oil, grease, or lubricants from metal parts. No data is available about the potential biological health hazards in such system. Thus, a health risk assessment linked to the bacterial populations present in this new degreasing technology is, therefore, necessary for workers. We performed both cultural and molecular approaches in several biological degreasing systems for various industrial contexts to investigate the composition and dynamics of bacterial populations. These biological degreasing systems did not work with the original bacterial populations. Indeed, they were colonized by a defined and restricted group of bacteria. This group replaced the indigenous bacterial populations known for degrading complex substrates. Klebsiella pneumoniae, Klebsiella oxytoca, Pseudomonas aeruginosa, and Pantoea agglomerans were important members of the microflora found in most of the biological degreasing systems. These bacteria might represent a potential health hazard for workers.

Evaluation of a suitable DNA damage biomarker for human biomonitoring of exposed workers

The objective of this study was to identify a sensitive and noninvasive biomarker of early genotoxic effects, for health risk assessment of workers exposed to mixtures of low doses of xenobiotics. We studied 30 workers exposed to antineoplastic drugs, 57 workers exposed to different mixtures of polycyclic aromatic hydrocarbons (PAHs) (41 airport workers and 16 paving workers) and 76 controls. Comet and micronucleus (MN) tests were performed on lymphocytes and exfoliated buccal cells. The MN assay on lymphocytes did not show significant differences between exposed and controls, while the MN assay on exfoliated buccal cells showed higher values in workers exposed to antineoplastics as compared with controls (0.85 vs. 0.48, P = 0.042). The comet assay on lymphocytes showed a higher comet percentage value (18.11 vs. 11.24 in controls, P = 0.001) and mean tail moment (TM) value (21.84 vs. 16.72 in controls, P = 0.003) in individuals exposed to PAHs as compared with controls; no significant differences were found in exposed to antineoplastics. The comet assay on exfoliated buccal cells did not show significant differences between exposed and control groups for comet percentages, whereas the TM value was higher in workers exposed to PAHs (55.1 vs. 32.31 for controls, P < 0.001). These results show that exfoliated buccal cells, obtained by a noninvasive procedure, represent robust target cells to assess the occupational exposure to inhalable mixture of chemicals at low doses. The comet assay seems to be suitable to promptly evaluate the genotoxic effects of PAHs mixtures that also contain volatile substances. The MN test is suitable to evaluate the effects of antineoplastics. Inc.

Oral Carcinogenicity and Toxicity of 2‐Amino‐4‐chlorophenol in Rats

This study was carried out to clarify the subchronic and chronic toxicity, and carcinogenicity of 2-amino-4-chlorophenol(ACP). Carcinogenicity, and chronic and subchronic toxicity of ACP were examined by feeding 10 rats of both sexes ACP-containing diet at a dose level of 0 (control), 512, 1,280, 3,200, 8,000 or 20,000 ppm (w/w) for 13 wk and 50 rats of both sexes at a dose level of 0, 1,280, 3,200 or 8,000 ppm for 2 yr. The 13-wk oral subchronic toxicity of ACP was characterized by proliferative lesions leading to development of tumors in the forestomach and urinary bladder and by erythrocyte toxicity as evidenced by decreases in red blood cell counts, hemoglobin and hematocrit and concurrent increases in methemoglobin levels and reticulocyte counts. Both simple and papillary and/or nodular types of transitional cell hyperplasias were observed in the urinary bladder of ACP-fed male rats. The proliferative lesions appeared at higher doses of ACP after the 13-wk administration than clear erythrocyte toxicity did. The 2-yr oral administration of ACP significantly increased incidences of squamous cell papillomas and carcinomas in the forestomach of male and female rats and transitional cell carcinomas in the urinary bladder of male rats. These tumor incidences increased dose-dependently. Notably, clear signs of erythrocyte toxicity were not evident after the 2-yr administration of ACP. Clear evidence of carcinogenic activity of ACP was shown in male and female rats. These data might be useful for the health risk assessment of workers exposed to ACP.

Health Risk Assessment of Workers' Exposure to Organic Compounds in a Tire Factory

This study focuses on a health risk assessment related to chemical exposure via inhalation for workers in a tire factory. Specifically, several volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs) were measured in the four different points of the vulcanization unit. A chemical transport model was developed in order to better represent the workers' exposure to the chemicals. Then, a risk assessment methodology was employed to evaluate the potential adverse health effects of the chemicals according to their carcinogenicities. Concentrations measured near the milling machine and press in the vulcanization unit were generally higher than the respective occupational exposure limit values. The corresponding estimated cumulative cancer risks for the carcinogens at the each sampling point were higher than the designated acceptable risk level of 1 × 10− 4. With respect to non-carcinogenic risks, the hazard indexes, both individually and cumulatively, were lower than the specified level of one. The high cancer risk estimated in this study suggests that the VOCs and SVOCs exposure for workers in the vulcanization unit should not be neglected. The results obtained in this study are valuable to plant managers, government officials, and regulators in the risk evaluation process.