Exposure to organic solvents among handicraft car painters: A pilot study in Italy

Using biomonitoring as a complementary approach in BTEX exposure assessment in the general population and occupational settings: a systematic review and meta-analysis

Hazardous organic compounds such as benzene, toluene, ethylbenzene, o-xylene, m-xylene, and p-xylene (known as BTEX) found at work and at home can cause adverse health effects of human beings throughout their lives. Biological monitoring, an exposure assessment method, considers all exposed organic and non-organic compounds. Our goal was to perform a systematic review and a statistical analysis (meta-analysis) of peer-reviewed publications to assess urinary concentrations of BTEX biomarkers in both occupationally-exposed population and the general population. Several major electronic databases, including Scopus, Embase, Medline, Web of Science, and Google scholar (grey literature), were searched for biomonitoring studies of BTEX. Overall, 33 studies met the eligible criteria for the systematic review and six met the full inclusion criteria for meta-analysis. For meta-analysis, we included studies in which unmetabolized BTEX compounds were measured in urine samples. Due to insufficient data, studies that measured BTEX metabolites in urine samples and unmetabolized BTEX compounds in blood samples were excluded from the meta-analysis but were analyzed in the qualitative synthesis. Most studies showed increased urinary concentrations of BTEX in exposed individuals (mainly workers) compared to unexposed individuals. The results showed that the highest total BTEX concentrations were recorded in painters and policemen. This study showed that the undoubted associations between lifestyle and environmental factors and urinary levels of BTEX or its metabolites have not yet been confirmed in current biomonitoring studies. This is attributed to the few studies reported in this research area, the lack of homogeneous information, and the disagreement in the published results of the studies.

[Cancer risk evaluation in individuals occupationally exposed to organic solvents]

OBJECTIVE

To evaluate the frequency of micronuclei (MNs) and influence of GSTM1 and GSTT1 gene polymorphisms as biomarkers of cancer risk in car painters (n=152) compared to unexposed individuals (n=152).

METHODS

Molecular epidemiology study, cross-sectional analysis of gen and environment interaction. The evaluation of MN and genetic polymorphisms was determined by molecular tests in lymphocytes from subjects involved in the study.

RESULTS

It was determined that the frequency of MNs is 1.6 higher in the exposed group compared to the reference group (1.39 ± 0.92 versus 0.87 ± 0.78, p<0.0001). There was no increase in the frequency of MNs associated with the polymorphisms in GSTM1 and GSTT1.

CONCLUSIONS

The increase of MNs in car painters serves to alert the increased risk of cancer in this population exposed to organic solvents. These results can be used in Occupational Epidemiological Surveillance Programs, as a prevention strategy and policies to regulate and control the use of solvents at a national level and in other countries with a large informal sector of individuals exposed to these chemicals to reduce the risk of cancer.

A Preliminary Assessment of Health and Safety in the Automobile Industry in Brunei Darussalam: Workers' Knowledge and Practice of Organic Solvents

Automobile industries worldwide extensively use organic solvents. Yet, limited studies have examined the health and safety of handling these solvents, which can only be assured if workers have appropriate knowledge and demonstrate safe practices. A cross-sectional study was conducted to preliminary explore the knowledge and practice among workers who are involved in handling organic solvents in the automobile industry in the largest urban district in Brunei Darussalam. Qualitative data were sourced from open-ended questions, observations, and pictorial evidence through still photographs. Quantitative analysis showed that 75% of the workers practice reading labels, 94.1% use fully covered clothes, 82.4% wear gloves, and 98.5% practice proper hand washing. Furthermore, 98.5% of workers cover container lids. The qualitative analysis illustrated that workers have general knowledge of materials containing solvents but could not identify the exact solvents, the harmful effects of the solvents, pathophysiology, and harmful effects on specific body systems. Health and safety were found to be practiced, albeit not consistently. Health and Safety Authorities in Brunei Darussalam must review and enforce specific policies on the use of organic solvents so that they can be practiced consistently and safely in the automobile industry. Cooperation and collaboration in adhering to the policies are mandatory to ensure health and safety at work.

Volatile organic compounds: A proinflammatory activator in autoimmune diseases

The etiopathogenesis of inflammatory and autoimmune diseases, including pulmonary disease, atherosclerosis, and rheumatoid arthritis, has been linked to human exposure to volatile organic compounds (VOC) present in the environment. Chronic inflammation due to immune breakdown and malfunctioning of the immune system has been projected to play a major role in the initiation and progression of autoimmune disorders. Macrophages, major phagocytes involved in the regulation of chronic inflammation, are a major target of VOC. Excessive and prolonged activation of immune cells (T and B lymphocytes) and overexpression of the master pro-inflammatory constituents [cytokine and tumor necrosis factor-alpha, together with other mediators (interleukin-6, interleukin-1, and interferon-gamma)] have been shown to play a central role in the pathogenesis of autoimmune inflammatory responses. The function and efficiency of the immune system resulting in immunostimulation and immunosuppression are a result of exogenous and endogenous factors. An autoimmune disorder is a by-product of the overproduction of these inflammatory mediators. Additionally, an excess of these toxicants helps in promoting autoimmunity through alterations in DNA methylation in CD4 T cells. The purpose of this review is to shed light on the possible role of VOC exposure in the onset and progression of autoimmune diseases.

Biomonitoring of Workers Exposed to Volatile Organic Compounds Associated with Different Occupations by Headspace GC-FID

The present study has been undertaken to analyze the total accumulated burden of volatile organic compounds (VOCs) in blood of occupationally exposed workers. The headspace technique combined with gas chromatography with flame ionization detector was used for the quantitative analysis of the different volatile organic compounds (isopropyl alcohol, phenol, benzene, dichloromethane, ethanol, ethyl acetate, and toluene) in 80 blood samples from the workers belonging to different occupations i.e., shoe polish workers, thinner handlers, paint workers, furniture polish workers, petrol station attendants, textile dyeing workers, printing press workers, and dry port workers as biomonitoring is one of the most promising methods for analyzing the individual burden of VOCs. Another purpose of this study was to investigate the correlation between detected concentrations of VOCs and associated health issues reported by the workers of these professions. Results of the study revealed the presence of different VOCs in blood samples of approximately 70 workers out of 80, and statistical analysis proved a strong relationship between the reported work experience, working hours, and diseases and the detected concentrations of respective volatile organic compounds.

Risk Assessment of Benzene, Toluene, Ethyl Benzene, and Xylene Concentrations from the Combustion of Coal in a Controlled Laboratory Environment

A D-grade type coal was burned under simulated domestic practices in a controlled laboratory set-up, in order to characterize the emissions of volatile organic compounds (VOCs); namely, benzene, toluene, ethylbenzene, and xylenes (BTEX). Near-field concentrations were collected in a shack-like structure constructed using corrugated iron, simulating a traditional house found in informal settlements in South Africa (SA). Measurements were carried out using the Synspec Spectras GC955 real-time monitor over a three-hour burn cycle. The 3-h average concentrations (in µg/m³) of benzene, toluene, ethylbenzene, p-xylene, and o-xylene were 919 ± 44, 2051 ± 91, 3838 ±19, 4245 ± 41 and 3576 ± 49, respectively. The cancer risk for adult males and females in a typical SA household exposure scenario was found to be 1.1 and 1.2 respectively, which are 110- and 120-fold higher than the U.S. Environmental Protection Agency (EPA) designated risk severity indicator (1 × 10-6). All four TEX (toluene, ethylbenzene, p-xylene and o-xylene) compounds recorded a Hazard Quotient (HQ) of less than 1, indicating a low risk of developing related non-carcinogenic health effects. The HQ for TEX ranged from 0.001 to 0.05, with toluene concentrations being the lowest, and ethylbenzene the highest. This study has demonstrated that domestic coal burning may be a significant source of BTEX emission exposure.

Critique of the IARC 100F Working Group Evaluation of Occupational Benzene Exposure: Suggestions for the October 2017 Benzene-Only Working Group Meeting

Health agencies and institutions utilize International Agency for Research on Cancer (IARC) monographs because they are said to represent authoritative cancer evaluations and scientific references. The United States National Cancer Institute has provided support for the IARC Monographs Program for more than three decades. The Volume 100F Monograph, which was published in 2012, reports the evaluations of benzene and more than two dozen other agents performed by the IARC Working Group (WG) that met in Lyon, France from 20 to 27 October 2009. All had already been judged to be human carcinogens. This commentary discusses errors in the occupational exposure section (1.1.3) of the 100F Benzene Monograph ("monograph"). Millions of workers in developed and developing countries have long been known to be routinely exposed to benzene. Since exposures may exceed occupational exposure limits, the hope is that this commentary will be considered by the IARC benzene-only WG at its meeting in October 2017.

Evaluating the impact of ambient benzene vapor concentrations on product water from Condensation Water From Air technology

Globally, drinking water resources are diminishing in both quantity and quality. This situation has renewed interest in Condensation Water From Air (CWFA) technology, which utilizes water vapor in the air to produce water for both potable and non-potable purposes. However, there are currently insufficient data available to determine the relationship between air contaminants and the rate at which they are transferred from the air into CWFA untreated product water. This study implemented a novel experimental method utilizing an environmental test chamber to evaluate how air quality and temperature affects CWFA untreated product water quality in order to collect data that will inform the type of water treatment required to protect human health. This study found that temperature and benzene air concentration affected the untreated product water from a CWFA system. Benzene vapor concentrations representing a polluted outdoor environment resulted in benzene product water concentrations between 15% and 23% of the USEPA drinking water limit of 5μg/l. In contrast, product water benzene concentrations representing an indoor industrial environment were between 1.4 and 2.4 times higher than the drinking water limit. Lower condenser coil temperatures were correlated with an increased concentration of benzene in the product water. Environmental health professionals and engineers can integrate the results of this assessment to predict benzene concentrations in the product water and take appropriate health protective measures.

Comparison of the volatile organic compound recovery rates of commercial active samplers for evaluation of indoor air quality in work environments

The Industrial Safety and Health Law in Japan established administrative levels for volatile organic compounds (VOCs) in indoor air. In the present study, these 49 VOCs were extracted from the absorbents of commercial active samplers from Sibata Scientific Technology (carbon-bead active sampler), SKC Inc. (Anasorb CSC sorbent tube), and Gastec (bead-shaped activated carbon tube) using carbon disulfide, and the recovery rates were compared. The VOCs were added to the adsorbents at three concentration levels relative to the administrative levels (×0.5, ×1, and ×2). The following mean recovery rates of the 49 VOCs were obtained at the ×0.5, ×1, and ×2 levels: 86, 93, and 92% for the Sibata sampler; 78, 82, and 84% for the SKC sampler; and 94, 93, and 90% for the Gastec sampler. With the Sibata sampler, the recovery rates of 78% (×0.5), 84% (×1), and 90% (×2) of the VOCs measured in this study were adequate (80-120%); the corresponding percentages for the SKC sampler were 67% (×0.5), 69% (×1), and 69% (×2), and those for the Gastec sampler were 92% (×0.5), 86% (×1), and 86% (×2). The effects of the octanol-water partition coefficients and vapor pressures of the VOCs on the recovery rates were investigated. The recovery rates increased with increases in the octanol-water partition coefficient and the vapor pressure and then leveled off. The recovery rates for the o-, m-, and p-cresol isomers were much lower than those obtained for other VOCs at all three concentration levels and with all samplers.

[Occupational exposure to benzene in Brazil: estimates based on an occupational exposure matrix]

This study estimates the number of exposed workers and the prevalence of occupational benzene exposure in Brazil. Due to the lack of available local measurements for the study, data were used from an occupational exposure matrix, the Finnish National Job-Exposure Matrix (FINJEM), which covers proportions of individuals exposed to benzene, calculated as environmental measures. In Brazil, the 2010 Demographic Census identified 86,353,839 workers in the workforce and employed. Applying the FINJEM parameters, an estimated 7,376,761 (8.5%) belonged to potentially exposed occupational groups, while 770,212 were considered exposed to benzene, corresponding to an occupational group-weighted prevalence of 0.9%, higher in men (1.1%) than in women (0.6%). Exposed individuals were concentrated in the category of Machine and Motor Operators and Mechanics (62%). The number of exposed and prevalence of occupational exposure to benzene are high, even when compared to Finnish parameters, suggesting the need for monitoring and control of this carcinogen in Brazil.

Exposición a COVs en fábricas de muebles de dos poblaciones del norte de Colombia

<p><strong>Objetivos</strong> Evaluar la exposición a compuestos orgánicos volátiles (COVs) en trabajadores de fábricas artesanales de mueblesde dos poblaciones de Sucre (Sincelejo y Sampués), Norte de Colombia. Determinar posibles signos y/o síntomas relacionados con la exposición a estos contaminantes.</p><p><strong>Métodos </strong>Estudio transversal analíticocon aplicación de una encuesta. La población objetivo estuvo conformada por 66 individuos, 41 expuestos y 25 controles. Se tomaron muestras personales para las concentraciones de benceno, tolueno, etilbenceno y xilenos (en ambos grupos) y se contrastó con posibles efectos en la salud atribuidos a estos contaminantes.</p><p><strong>Resultados </strong>Las concentraciones de benceno, tolueno y m/p-xileno fueron mayores en el grupo expuesto (9,5 mg/m³, 8,1 mg/m³ y 12,1 mg/m³) en comparación con el grupo control(0,2 mg/m³, 0,3 mg/m³ y 0,03 mg/m³).Dolor muscular 82,9 % (RP=3,8; IC95%:1,2-11,8) y somnolencia 65,9 % (RP=4,9; IC95%:1,7-14,7)estuvieron asociados a mayor exposición (p&lt; 0,05). Factores como el uso de mezclas solventes (thinner) en el trabajo y el tráfico vehicularpueden contribuir a estos resultados.</p><p><strong>Conclusiones </strong>La contribución de diversas fuentes aumenta la exposición personal a los COVs, de los trabajadores de las fábricas artesanales de muebles en el Norte de Colombia. Adicionalmente, el uso excesivo de estos compuestos puede estar generando efectos adversos en la salud de los trabajadores.</p>

Benzene exposure among auto-repair workers from workplace ambience: a pioneer study from Pakistan

OBJECTIVES

In Pakistan, the reports on benzene exposure among workers in chemical industries are almost non-existing due to limited research work in the field of exposure science. This study aimed to investigate such exposure in a widely adopted occupation in Rawalpindi city.

MATERIAL AND METHODS

In this cross-sectional study, 60 blood samples (N = 20/group) of mechanics (MCs), spray painters (PNs) and control participants (CN) were analyzed. The socio-economic and demographic information of workers and that of workplaces was documented using a short questionnaire.

RESULTS

We identified that the workers in spray-painting occupation are highly at risk of benzene exposure. The results showed that PNs were more at risk of exposure to benzene than MCs, and this exposure was significantly correlated with long working hours (r = 0.68, p < 0.001). Moreover, there are several limitations in workplace setups, which need to be addressed in order to mitigate workers health risk in this occupation. In addition to the reckless use of chemicals, other identified predictors of exposure included active and passive smoking, poor workplace hygiene and substandard ventilation.

CONCLUSIONS

To mitigate workplace exposure, it is necessary to reduce working hours and encourage regular use of self-protective equipments and adoption of proper hygiene in chemical workplaces.

A comparison of owner and expert evaluation of health and safety in small collision repair shops: a pilot study

BACKGROUND

Workplace evaluation is one of the first steps in reducing the risk of injuries and illnesses, and is part of several programs that promote a participatory approach to occupational health among small business owners. The usefulness of written safety evaluations is contingent upon non-safety professionals obtaining accurate and reliable results.

OBJECTIVES

The purpose of this study was to better understand auto body shop owners' ability to correctly identify occupational health and safety issues within their businesses.

METHODS

In this study, 11 auto body shop owners used a 25-question checklist, developed specifically for this industry, to identify key safety and health problems. Owner results were compared with those of an industrial hygienist (IH) experienced in using the assessment form.

RESULTS

The average number of safety problems identified by the IH was twice as large as the number identified by business owners (P = 0.02). The average percentage agreement of answers between owners and the IH was 81% (SD = 21%). Shop owners were more accurate in assessing the presence of written safety programs and records than the presence of unsafe work conditions. Overall, owners' sensitivity (ability to correctly identify a safety-deficient item) was low (0.22).

CONCLUSIONS

Collision shop owners had some difficulty correctly identifying many unsafe/non-compliant items or situations in their facility. Naïve users' ability to correctly identify potentially hazardous situations--sensitivity--should be the metric of concern for the validity of safety assessments, and efforts should be directed at bringing this number as close to one as feasible.

Air monitoring of aromatic hydrocarbons during automobile spray painting for developing change schedule of respirator cartridges

In the absence of End of Service Life Indicator (ESLI), a cartridge change schedule should be established for ensuring that cartridges are changed before their end of service life. Factors effecting service life of cartridges were evaluated, including the amount of atmospheric contamination with aromatic hydrocarbon vapors in the workplace, temperature, and relative humidity of the air. A new change schedule was established based on comparing the results of air monitoring and workplace conditions, laboratory experiment, and the NIOSH MultiVapor software. Spray painters were being exposed to aromatic hydrocarbons in a range exceeding occupational exposure limits. The cartridge change schedule was not effective and could no longer provide adequate protection against organic contaminants for sprayers. Change schedules for respirator cartridges should be reduced from 16-24 hours to 4 hours. NIOSH's service life software program could be applied to developing cartridge change schedules.

Risk assessment of volatile organic compounds benzene, toluene, ethylbenzene, and xylene (BTEX) in consumer products

Exposure and risk assessment was performed by evaluating levels of volatile organic compounds (VOC) benzene, toluene, ethylbenzene, and xylene (BTEX) in 207 consumer products. The products were categorized into 30 different items, consisting of products of different brands. Samples were analyzed for BTEX by headspace-gas chromatography/mass spectrometry (headspace-GC/MS) with limit of detection (LOD) of 1 ppm. BTEX were detected in 59 consumer products from 18 item types. Benzene was detected in whiteout (ranging from not detected [ND] to 3170 ppm), glue (1486 ppm), oil-based ballpoint pens (47 ppm), and permanent (marking) pens (2 ppm). Toluene was detected in a leather cleaning product (6071 ppm), glue (5078 ppm), whiteout (1130 ppm), self-adhesive wallpaper (15-1012 ppm), shoe polish (806 ppm), permanent pen (609 ppm), wig adhesive (372 ppm), tapes (2-360 ppm), oil-based ballpoint pen (201 ppm), duplex wallpaper (12-52 ppm), shoes (27 ppm), and air freshener (13 ppm). High levels of ethylbenzene were detected in permanent pen (ND-345,065 ppm), shoe polish (ND-277,928 ppm), leather cleaner (42,223 ppm), whiteout (ND-2,770 ppm), and glue (ND-792 ppm). Xylene was detected in permanent pen (ND-285,132 ppm), shoe polish (ND-87,298 ppm), leather cleaner (12,266 ppm), glue (ND-3,124 ppm), and whiteout (ND-1,400 ppm). Exposure assessment showed that the exposure to ethylbenzene from permanent pens ranged from 0 to 3.11 mg/kg/d (men) and 0 to 3.75 mg/kg/d (women), while for xylene, the exposure ranges were 0-2.57 mg/kg/d and 0-3.1 mg/kg/d in men and women, respectively. The exposure of women to benzene from whiteout ranged from 0 to 0.00059 mg/kg/d. Hazard index (HI), defined as a ratio of exposure to reference dose (RfD), for ethylbenzene was 31.1 (3.11 mg/kg/d/0.1 mg/kg/d) and for xylene (2.57 mg/kg/d/0.2 mg/kg/d) was 12.85, exceeding 1 for both compounds. Cancer risk for benzene was calculated to be 3.2 × 10(-5) based on (0.00059 mg/kg/d × 0.055 mg/kg-d(-1), cancer potency factor), assuming that 100% of detected levels in some products such as permanent pens and whiteouts were exposed in a worst-case scenario. These data suggest that exposure to VOC via some consumer products exceeded the safe limits and needs to be reduced.

Human biological monitoring of suspected endocrine-disrupting compounds

Endocrine-disrupting compounds are exogenous agents that interfere with the natural hormones of the body. Human biological monitoring is a powerful method for monitoring exposure to endocrine disrupting compounds. In this review, we describe human biological monitoring systems for different groups of endocrine disrupting compounds, polychlorinated biphenyls, brominated flame retardants, phthalates, alkylphenols, pesticides, metals, perfluronated compounds, parabens, ultraviolet filters, and organic solvents. The aspects discussed are origin to exposure, metabolism, matrices to analyse, analytical determination methods, determinants, and time trends.

Hematological Evidence of Occupational Exposure to Chemicals and Other Factors among Auto-Repair Workers in Rawalpindi, Pakistan

Objectives

Occupational exposure to aromatic solvents causes many serious health hazards to workers, especially if an ambient environment increases the exposure during routine working hours. This study was conducted on two related groups, i.e., automobile mechanics (MCs) and automobile spray painters (PNs), with an effort to analyze effects of chemical exposure on hematological parameters, keeping a focus on environmental parameters and workers’ personal behavioral characteristics that could be held responsible for increasing exposure risk.

Methods

A preliminary survey of various chemicals used in these places was done, and 78 blood samples were collected from three groups (control, n = 24; mechanics, n = 25; painters, n = 29). Demographic features of workers were recorded through a short questionnaire.

Results

Results showed that mean red blood cell (RBC) count was lower both in MCs [t(51) = 2.38, p < 0.021, r = 0.32] and in PNs [t(47) = 2.12, p < 0.03, r = 0.29], whereas mean hemoglobin (Hb) was significantly lower in MCs [t(51) = 2.5, p = 0.017, r = 0.33]. Combined data for exposed groups for smokers (SMs) versus nonsmokers (NSs) showed that SMs had a significantly lower number (RBC count: t(52) = 2.28, p < 0.027, r = 0.25; Hb count: t(52) = 2.71, p < 0.009, r = 0.30] of these parameters than NSs, even compared to the control group. Moreover, logistic regression results showed that smoking is a significant predictor of reduction in RBC and Hb counts, besides occupational exposure and work experience to a little extent among exposed workers. Mean white blood cell count [t(47) = 2.63, p < 0.01, r=0.35], mean corpuscle volume [t(47)= –2.82, p = 0.007, r = 0.29], and packed cell volume [t(47)= –2.28, p = 0.027, r = 31] were higher exclusively in painters, which could be related to exposure to benzene in addition to isocyanate.

Conclusion

It appeared that workplace exposure may be complex due to interaction of multiple factors and PNs face much more exposure to isocyanate and aromatic solvents than MCs, which had significant effects on their hematopoiesis. Smoking enhances exposure risk manifolds, and among MCs it showed combined effects along with occupational exposure. There is a need to create awareness among these workers to adopt self-safety measures during routine tasks and also of a separate study to elucidate actual occupational exposure among them, eliminating confounding factors.

Chemical exposure in occupational settings and related health risks: a neglected area of research in Pakistan

In Pakistan a huge number of workers is routinely exposed to various types of chemical contaminants but there is a dearth of information as to the impact of these agents, due to a lack of a routine surveillance system and proper reporting. Prolonged and sometimes acute occupational exposures to varied organic chemicals may result in numerous health related problems. Studies from all over the world have shown adverse health outcomes of chemicals that are commonly used in various occupations. Such chemical exposures are not just confined to the workplace, but the residents surrounding industrial sites also face significant health risks due to indirect chemical exposure. Occupational exposure is a multidimensional risk factor that varies from one occupation to another, and is associated with health decline in workers. Common determinants of workplace hazards include improper, or lack of use of self-protective equipment, active and passive exposure to cigarette smoke as well as the socio-demographic and economic background of workers. There may be more than one cause of occupational stress and psychophysical disturbance among workers such as workload, lower salaries, and lack of social and medical facilities; indeed, their general health is poor. Therefore, in Pakistan, it is particularly important to focus on these issues and set rules and regulations to create occupational hazard awareness among workers, which will promote health safety at work places. If priorities are given to the correct use of self-protective equipment, adopting proper hygiene at the workplace and to avoid smoking, occupational exposures and consequent health risks may be minimized significantly.

Evaluation of neuropsychological symptoms and exposure to benzene, toluene and xylene among two different furniture worker groups in Izmir

This study was conducted to determine whether there was any exposure to toluene, xylene and benzene and to assess the health impact of these solvents on workers in furniture enterprises in Karabaglar, Izmir. This cross-sectional study covered furniture enterprises in Karabaglar, Izmir. This study was comprised of an exposed group consisting of workers engaged in painting and varnishing and therefore exposed either directly or indirectly toluene, xylene and benzene in the workplace and the non-exposed group engaged in other aspects of production. While a total of 261 individuals completed questionnaires, 210 workers agreed to provide blood samples. Blood solvents levels were determined using gas chromatograph at Ege University, Intoxication Research and Application Centre. The modified EUROQUEST questionnaire was used to assess neuropsychological symptoms and neurological and general examination were performed. Occupational and exposure history, demographic and work-related information was collected. In this study of workers, blood toluene and benzene levels were found to be significantly higher among those engaged in painting and varnishing compared to those who perform other tasks. The average blood toluene and benzene concentrations among exposed workers were 6.95 times and 1.64 times respectively higher than those in the nonexposed groups. Smokers and participants who worked in excess of 8 hours/day had higher blood toluene and benzene levels. The most frequently work-related health complaints were back pain, allergies and asthma. No differences were found in the average scores in the neuropsychological symptoms questionnaire between exposed and non-exposed groups. Neurological examination of two individuals with these complaints revealed a loss of reflexes. The workers were unaware that they were being exposed to solvents at work. Tobacco smoke is a major source of internal exposure to benzene. Improving working conditions in furniture work places is a priority.

Benzene exposure in childhood: Role of living environments and assessment of available tools

Benzene is a widespread air pollutant and a well-known human carcinogen. Evidence is needed regarding benzene intake in the pediatric age group. We investigated the use of urinary (u) trans,trans-muconic acid (t,t-MA), S-phenylmercapturic acid (SPMA), and unmodified benzene (UB) for assessing exposure to low concentrations of environmental benzene and the role of living environment on benzene exposure in childhood. u-t,t-MA, u-SPMA, u-UB and u-cotinine were measured in urine samples of 243 Italian children (5-11 years) recruited in a cross-sectional study. Analytical results were compared with data obtained from questionnaires about participants' main potential exposure factors. u-UB, u-t,t-MA and u-SPMA concentrations were about 1.5-fold higher in children living in urban areas than in those in the rural group. Univariate analyses showed that u-UB was the only biomarker able to discriminate secondhand smoke (SHS) exposure in urban and rural children (medians=411.50 and 210.50 ng/L, respectively); these results were confirmed by the strong correlation between u-UB and u-cotinine in the SHS-exposed group and by multivariate analyses. A regression model on u-SPMA showed that the metabolite is related to residence area (p<0.001), SHS exposure (p=0.048) and gender (p=0.027). u-UB is the best marker of benzene exposure in children in the present study, and it can be used as a good carcinogen-derived biomarker of exposure to passive smoking, especially related to benzene, when urine sample is collected at the end of the day. In addition, it is important to highlight that SHS resulted the most important contributor to benzene exposure, underlining the need for an information campaign against passive smoking exposure.

Health risk assessment of exposure to selected volatile organic compounds emitted from an integrated iron and steel plant

Workplace air samples from sintering, cokemaking, and hot and cold forming processes in the integrated iron and steel industry were analyzed to determine their volatile organic compound (VOC) concentration. Sixteen VOC species including three paraffins (cyclohexane, n-hexane, methylcyclohexane), five chlorinated VOC species (trichloroethylene, 1,1,1-trichloroethane, tetrachloroethylene, chlorobenzene, 1,4-dichlorobenzene), and eight aromatics (benzene, ethylbenzene, styrene, toluene, m,p-xylene, o-xylene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene) were selected to measure their noncancer risk for workers. Concentrations of toluene, xylene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, dichlorobenzene, and trichloroethylene were high in all four processes. Carbon tetrachloride and tetrachloroethylene concentrations were high in the hot and cold forming processes. The noncancer risk followed the increasing order: cokemaking > sintering > hot forming > cold forming. 1,2,4-trimethylbenzene and 1,3,5-trimethylbenzene contributed 44% to 65% and 13% to 20% of noncancer risk, respectively, for the four processes. Benzene accounted for a high portion of the noncancer risk in cokemaking. The hazard index (HI: 17-108) of the average VOC concentrations suggests that health risks can be reduced by improving workplace air quality and protecting workers.

Occupational exposure to organic solvents during bridge painting

Exposure to volatile organic compounds (VOCs) from bridge painting was measured in New York City and New Jersey during the summer and fall seasons from 2005 to 2007. The effect of painting activities (paint coating layer, confinement setup, and application method) and meteorological conditions (temperature, humidity, and wind speed) on solvent exposure to aromatic, ketone, ester, and alkane compounds were individually evaluated. Mixed-effect models were used to examine the combination effects of these factors on the air concentration of total VOCs as the individual compound groups were not present in all samples. Air concentration associated with spraying was not affected by meteorological conditions since spraying was done in a confined space, thus reducing their impact on solvent air concentration. The mixed models for brushing and rolling samples included two fixed factors, i.e. application method and temperature, and one random factor, i.e. sampling day. An independent dataset (daily air samples) was used to validate the mixed model constructed for brushing and rolling samples. The regression line of the predicted values and actual measurements had a slope of 1.32 +/- 0.15 for daily brushing and rolling samples, with almost all points being within the 95% confidence bands. The constructed model provides practical approaches for estimating the solvent exposure from brushing and rolling activities among construction painters. An adjusted mean air concentration derived from the activity-specific spray samples was the best estimate for that painting application.

Benzene exposure: an overview of monitoring methods and their findings

Benzene has been measured throughout the environment and is commonly emitted in several industrial and transportation settings leading to widespread environmental and occupational exposures. Inhalation is the most common exposure route but benzene rapidly penetrates the skin and can contaminant water and food resulting in dermal and ingestion exposures. While less toxic solvents have been substituted for benzene, it still is a component of petroleum products, including gasoline, and is a trace impurity in industrial products resulting in continued sub to low ppm occupational exposures, though higher exposures exist in small, uncontrolled workshops in developing countries. Emissions from gasoline/petrochemical industry are its main sources to the ambient air, but a person's total inhalation exposure can be elevated from emissions from cigarettes, consumer products and gasoline powered engines/tools stored in garages attached to homes. Air samples are collected in canisters or on adsorbent with subsequent quantification by gas chromatography. Ambient air concentrations vary from sub-ppb range, low ppb, and tens of ppb in rural/suburban, urban, and source impacted areas, respectively. Short-term environmental exposures of ppm occur during vehicle fueling. Indoor air concentrations of tens of ppb occur in microenvironments containing indoor sources. Occupational and environmental exposures have declined where regulations limit benzene in gasoline (<1%) and cigarette smoking has been banned from public and work places. Similar controls should be implemented worldwide to reduce benzene exposure. Biomarkers of benzene used to estimate exposure and risk include: benzene in breath, blood and urine; its urinary metabolites: phenol, t,t-muconic acid (t,tMA) and S-phenylmercapturic acid (sPMA); and blood protein adducts. The biomarker studies suggest benzene environmental exposures are in the sub to low ppb range though non-benzene sources for urinary metabolites, differences in metabolic rates compared to occupational or animal doses, and the presence of polymorphisms need to be considered when evaluating risks from environmental exposures to individuals or potentially susceptible populations.

Validation of urine density correction in cases of hippuric acid and un-metabolized toluene in urine of workers exposed to toluene

To investigate if it is appropriate to apply urine density correction when a urine sample is dense or dilute. Data on hippuric acid (HA-U), toluene (Tol-U), creatinine (CR) and specific gravity (SG) in end-of-shift urine samples and exposure to air-borne toluene were cited from previous publications. In practice, 837 cases were available, and they were classified into dense, intermediate and dilute groups taking 0.3 and 3.0 g/l of CR and 1.010 and 1.030 of SG as cut-off points. Lines of regression of HA-U and Tol-U (as observed, CR-corrected or SG-corrected) with air-borne toluene were calculated for each density groups, and correlation coefficients (CCs) were compared. The dense groups gave CCs similar to those of the intermediate groups. Dilute versus intermediate group comparison also gave promising results. These conclusions were however based primarily on the findings with observed values, because the numbers of cases in the dilute or dense group were limited when CR- or SG-correction was applied. Literature survey showed that urine density correction does not always improve the correlation between solvents in air and exposure makers in urine. It was concluded that no correction for urine density may be necessary in evaluating HA-U and Tol-U in dense (and probably also dilute) urine samples as markers of occupational toluene exposure. Just in case when correction for urine density is desired for any reason, SG-correction may be recommended.

Environmental and biological monitoring of volatile organic compounds in the workplace

The exposure of workers to volatile organic compounds (VOCs) in the workplace has been evaluated in four different occupations, namely: house painters, varnishing workers, car painters and petrol station workers. The study was carried out by analyzing the ambient air within the workers' breathing zone as well as the alveolar air of these workers, which was selected as the biomarker of exposure. Twenty six VOCs were measured in the air samples. Nearly all target VOCs were found in the ambient air of the workplaces assessed, usually involving in the most abundant compounds, toluene, o-xylene and N-butyl acetate, concentrations between 60 and 51,110 microg m(-3). The same VOCs were found in the alveolar air of workers after their work shift, at concentrations whose amount depended on the compound and occupation involved. Toluene, at concentrations between 90 and 29,840 microg m(-3), o-xylene, between 30 and 12,285 microg m(-3), and N-butyl acetate, between 10 and 8045 microg m(-3), were also the most abundant compounds found in the alveolar air of workers after exposure. The post-work concentrations of VOCs in alveolar air correlated significantly with ambient air concentrations, obtaining correlation coefficients over 0.9 for the compounds studied. Furthermore, a general trend towards greater absorption of benzene derivatives by the human body (the average percentage of absorption is 50%) than that of esters (average percentage of 20%) has been observed in the data obtained throughout the study.

Contact dermatitis in car repair workers

BACKGROUND

Occupational contact dermatitis (OCD) is a common skin disorder with a poor prognosis.

OBJECTIVES

The objectives of this study were to (1) estimate the prevalence of CD among car repair workers, (2) study some risk factors associated with CD, and (3) conduct an intervention skin care education program.

SUBJECTS AND METHODS

A cross-sectional study was conducted in 87 car repair workers with regular and direct exposure to chemicals at the industrial zone in Zagazig City, Egypt and 76 unexposed assembly booksellers. All workers were subjected to a questionnaire and clinical examination, and those who were diagnosed clinically as CD were patch tested. Intervention study with a skin care education program was carried out on 47 car repair workers. Re-evaluation of the intervention group after 5 months was done.

RESULTS

The total prevalence of CD among car repair workers (18.4%) was significantly higher compared with their controls (3.9%), with the highest prevalence among car mechanics (24.1%) and painters (20.7%); 16.1% of them reported recurrent dermatitis in the last 12 months. Nickel accounted for most positive patch test reactions (33.3%). A significant association was noticed between the prevalence of CD and age, smoking, atopic background and duration of work. After the intervention study, a significantly higher knowledge level about CD was reported.

CONCLUSION

The most important risk factors for OCD among the car repair workers are atopic background and long duration of work. Skin care education program is an important tool for prevention of CD and control of exposure to substances hazardous to the skin.