We conducted a repeated exposure-assessment survey for task-based breathing-zone concentrations (BZCs) of monomeric and polymeric 1,6-hexamethylene diisocyanate (HDI) during spray painting on 47 automotive spray painters from North Carolina and Washington State. We report here the use of linear mixed modeling to identify the primary determinants of the measured BZCs. Both one-stage (N = 98 paint tasks) and two-stage (N = 198 paint tasks) filter sampling was used to measure concentrations of HDI, uretidone, biuret, and isocyanurate. The geometric mean (GM) level of isocyanurate (1410 μg m−3) was higher than all other analytes (i.e. GM < 7.85 μg m−3). The mixed models were unique to each analyte and included factors such as analyte-specific paint concentration, airflow in the paint booth, and sampler type. The effect of sampler type was corroborated by side-by-side one- and two-stage personal air sampling (N = 16 paint tasks). According to paired t-tests, significantly higher concentrations of HDI (P = 0.0363) and isocyanurate (P = 0.0035) were measured using one-stage samplers. Marginal R2 statistics were calculated for each model; significant fixed effects were able to describe 25, 52, 54, and 20% of the variability in BZCs of HDI, uretidone, biuret, and isocyanurate, respectively. Mixed models developed in this study characterize the processes governing individual polyisocyanate BZCs. In addition, the mixed models identify ways to reduce polyisocyanate BZCs and, hence, protect painters from potential adverse health effects.
air sampling; exposure determinants; hexamethylene diisocyanate; isocyanate; statistical modeling
Isocyanate exposure was evaluated in 33 spray painters from 25 Washington State autobody shops. Personal breathing zone samples (n = 228) were analyzed for isophorone diisocyanate (IPDI) monomer, 1,6-hexamethylene diisocyanate (HDI) monomer, IPDI polyisocyanate, and three polyisocyanate forms of HDI. The objective was to describe exposures to isocyanates while spray painting, compare them with short-term exposure limits (STELs), and describe the isocyanate composition in the samples. The composition of polyisocyanates (IPDI and HDI) in the samples varied greatly, with maximum amounts ranging from up to 58% for HDI biuret to 96% for HDI isocyanurate. There was a significant inverse relationship between the percentage composition of HDI isocyanurate to IPDI and to HDI uretdione. Two 15-min STELs were compared: (1) Oregon's Occupational Safety and Health Administration (OR-OSHA) STEL of 1000 μg/m3 for HDI polyisocyanate, and (2) the United Kingdom's Health and Safety Executive (UK-HSE) STEL of 70 μg NCO/m3 for all isocyanates. Eighty percent of samples containing HDI polyisocyanate exceeded the OR-OSHA STEL while 98% of samples exceeded the UKHSE STEL. The majority of painters (67%) wore half-face air-purifying respirators while spray painting. Using the OROSHA and the UK-HSE STELs as benchmarks, 21% and 67% of painters, respectively, had at least one exposure that exceeded the respirator's OSHA-assigned protection factor. A critical review of the STELs revealed the following limitations: (1) the OR-OSHA STEL does not include all polyisocyanates, and (2) the UK-HSE STEL is derived from monomeric isocyanates, whereas the species present in typical spray coatings are polyisocyanates. In conclusion, the variable mixtures of isocyanates used by autobody painters suggest that an occupational exposure limit is required that includes all polyisocyanates. Despite the limitations of the STELs, we determined that a respirator with an assigned protection factor of 25 or greater is required to protect against isocyanate exposures during spray painting. Consequently, half-face air-purifying respirators, which are most commonly used and have an assigned protection factor of 10, do not afford adequate respiratory protection.
autobody; hexamethylene diisocyanate; occupational exposure limits; polyisocyanates; respiratory protection; STEL
Although urinary 1,6-hexamethylene diamine (HDA) is a useful biomarker of exposure to 1,6-hexamethylene diisocyanate (HDI), a large degree of unexplained intra- and inter-individual variability exists between estimated HDI exposure and urine HDA levels. We investigated the effect of individual and workplace factors on urine HDA levels using quantitative dermal and inhalation exposure data derived from a survey of automotive spray painters exposed to HDI. Painters' dermal and breathing-zone HDI-exposures were monitored over an entire workday for up to three separate workdays, spaced approximately one month apart. One urine sample was collected before the start of work with HDI-containing paints, and multiple samples were collected throughout the workday. Using mixed effects multiple linear regression modeling, coverall use resulted in significantly lower HDA levels (p = 0.12), and weekday contributed to significant variability in HDA levels (p = 0.056). We also investigated differences in urine HDA levels stratified by dichotomous and classification covariates using analysis of variance. Use of coveralls (p = 0.05), respirator type worn (p = 0.06), smoker status (p = 0.12), paint-booth type (p = 0.02), and more than one painter at the shop (p = 0.10) were all found to significantly affect urine HDA levels adjusted for creatinine concentration. Coverall use remained significant (p = 0.10), even after adjusting for respirator type. These results indicate that the variation in urine HDA level is mainly due to workplace factors and that appropriate dermal and inhalation protection is required to prevent HDI exposure.
To study inhalation and dermal exposure to hexamethylene diisocyanate (HDI) and its oligomers as well as personal protection equipment (PPE) use during task performance in conjunction with urinary hexamethylene diamine (HDA) in car body repair shop workers and industrial spray painters.
Personal task based inhalation samples (n = 95) were collected from six car body repair shops and five industrial painting companies using impingers with di‐n‐butylamine (DBA) in toluene. In parallel, dermal exposure was assessed using nitril rubber gloves. Gloves were submerged into DBA in toluene after sampling. Analysis for HDI and its oligomers was performed by LC‐MS/MS. Urine samples were collected from 55 workers (n = 291) and analysed for HDA by GC‐MS.
Inhalation exposure was strongly associated with tasks during which aerosolisation occurs. Dermal exposure occurred during tasks that involve direct handling of paint. In car body repair shops associations were found between detectable dermal exposure and glove use (odds ratio (OR) 0.22, 95% confidence interval (CI) 0.09 to 0.57) and inhalation exposure level (OR 1.34, 95% CI 0.97 to 1.84 for a 10‐fold increase). HDA in urine could be demonstrated in 36% and 10% of car body repair shop workers and industrial painting company workers respectively. In car body repair shops, the frequency of detectable HDA was significantly elevated at the end of the working day (OR 2.13, 95% CI 1.07 to 4.22 for 3–6 pm v 0–8 am). In both branches HDA was detected in urine of ∼25% of the spray painters. In addition HDA was detected in urine of a large proportion of non‐spray painters in car body repair shops.
Although (spray) painting with lacquers containing isocyanate hardeners results in the highest external exposures to HDI and oligomers, workers that do not perform paint related tasks may also receive a considerable internal dose.
isocyanate; oligomers; dermal; biomonitoring; spray painting
Urinary 1,6-hexamethylene diamine (HDA) may serve as a biomarker for systemic exposure to 1,6-hexamethylene diisocyanate (HDI) in occupationally exposed populations. However, the quantitative relationships between dermal and inhalation exposure to HDI and urine HDA levels have not been established. We measured acid-hydrolyzed urine HDA levels along with dermal and breathing-zone levels of HDI in 48 automotive spray painters. These measurements were conducted over the course of an entire workday for up to three separate workdays that were spaced approximately 1 month apart. One urine sample was collected before the start of work with HDI-containing paints and subsequent samples were collected during the workday. HDA levels varied throughout the day and ranged from nondetectable to 65.9 μg l−1 with a geometric mean and geometric standard deviation of 0.10 μg l−1 ± 6.68. Dermal exposure and inhalation exposure levels, adjusted for the type of respirator worn, were both significant predictors of urine HDA levels in the linear mixed models. Creatinine was a significant covariate when used as an independent variable along with dermal and respirator-adjusted inhalation exposure. Consequently, exposure assessment models must account for the water content of a urine sample. These findings indicate that HDA exhibits a biphasic elimination pattern, with a half-life of 2.9 h for the fast elimination phase. Our results also indicate that urine HDA level is significantly associated with systemic HDI exposure through both the skin and the lungs. We conclude that urinary HDA may be used as a biomarker of exposure to HDI, but biological monitoring should be tailored to reliably capture the intermittent exposure pattern typical in this industry.
biomarkers; creatinine; dermal exposure; 1,6-hexamethylene diamine; 1,6-hexamethylene diisocyanate; inhalation exposure; urine analysis
Quantification of amines in biological samples is important for evaluating occupational exposure to diisocyanates. In this study, we describe the quantification of 1,6-hexamethylene diamine (HDA) levels in hydrolyzed plasma of 46 spray painters applying 1,6-hexamethylene diisocyanate (HDI)-containing paint in vehicle repair shops collected during repeated visits to their workplace and their relationship with dermal and inhalation exposure to HDI monomer. HDA was detected in 76% of plasma samples, as heptafluorobutyryl derivatives, and the range of HDA concentrations was ≤0.02–0.92 μg l−1. After log-transformation of the data, the correlation between plasma HDA levels and HDI inhalation exposure measured on the same workday was low (N = 108, r = 0.22, P = 0.026) compared with the correlation between plasma HDA levels and inhalation exposure occurring ∼20 to 60 days before blood collection (N = 29, r = 0.57, P = 0.0014). The correlation between plasma HDA levels and HDI dermal exposure measured on the same workday, although statistically significant, was low (N = 108, r = 0.22, P = 0.040) while the correlation between HDA and dermal exposure occurring ∼20 to 60 days before blood collection was slightly improved (N = 29, r = 0.36, P = 0.053). We evaluated various workplace factors and controls (i.e. location, personal protective equipment use and paint booth type) as modifiers of plasma HDA levels. Workers using a downdraft-ventilated booth had significantly lower plasma HDA levels relative to semi-downdraft and crossdraft booth types (P = 0.0108); this trend was comparable to HDI inhalation and dermal exposure levels stratified by booth type. These findings indicate that HDA concentration in hydrolyzed plasma may be used as a biomarker of cumulative inhalation and dermal exposure to HDI and for investigating the effectiveness of exposure controls in the workplace.
biomarker; dermal exposure; 1,6-hexamethylene diamine (HDA); 1,6-hexamethylene diisocyanate (HDI); inhalation exposure; plasma
To determine the effectiveness of protective suits and gloves by biomonitoring.
Fifteen male spray painters at a ship coating factory were studied for two weeks. Workers wore no protective clothing during the first week and wore protective suits and gloves during the second week. Sampling was conducted on four consecutive working days each week. Ethyl benzene and xylene in the air were collected by using 3M 3500 organic vapour monitors. Urine was collected before and after each work shift.
Urinary mandelic acid (MA) and methyl hippuric acid (MHA) levels were divided by the personal exposure concentrations of ethyl benzene and xylene, respectively. Mean (SE) corrected MA and MHA concentrations in the first week were 1.07 (0.18) and 2.66 (0.68) (mg/g creatinine)/(mg/m3), and concentrations in the second week were 0.50 (0.12) and 1.76 (0.35) (mg/g creatinine)/(mg/m3) in the second week, respectively. Both MA and MHA concentrations in the second week (when spray painters wore protective suits and gloves) were lower than in the first week, respectively (p<0.001, p = 0.011). Mean decrease in MA and MHA biomarkers were 69% and 49%, respectively.
This study successfully evaluated the effectiveness of chemical protective suits and gloves by using biomarkers as urinary MA and MHA. This method is feasible for determining the performance of workers wearing personal protective equipment. Moreover, the experimental results suggest that dermal exposure may be the major contributor to total body burden of solvents in spray painters without protective suits and gloves.
Objectives: To identify and quantify determinants of captan exposure among 74 private orchard pesticide applicators in the Agricultural Health Study (AHS). To adjust an algorithm used for estimating pesticide exposure intensity in the AHS based on these determinants and to compare the correlation of the adjusted and unadjusted algorithms with urinary captan metabolite levels.
Methods: External exposure metrics included personal air, hand rinse, and dermal patch samples collected from each applicator on 2 days in 2002–2003. A 24-h urine sample was also collected. Exposure determinants were identified for each external metric using multiple linear regression models via the NLMIXED procedure in SAS. The AHS algorithm was adjusted, consistent with the identified determinants. Mixed-effect models were used to evaluate the correlation between the adjusted and unadjusted algorithm and urinary captan metabolite levels.
Results: Consistent determinants of captan exposure were a measure of application size (kilogram of captan sprayed or application method), wearing chemical-resistant (CR) gloves and/or a coverall/suit, repairing spray equipment, and product formulation. Application by airblast was associated with a 4- to 5-fold increase in exposure as compared to hand spray. Exposure reduction to the hands, right thigh, and left forearm from wearing CR gloves averaged ∼80%, to the right and left thighs and right forearm from wearing a coverall/suit by ∼70%. Applicators using wettable powder formulations had significantly higher air, thigh, and forearm exposures than those using liquid formulations. Application method weights in the AHS algorithm were adjusted to nine for airblast and two for hand spray; protective equipment reduction factors were adjusted to 0.2 (CR gloves), 0.3 (coverall/suit), and 0.1 (both).
Conclusions: Adjustment of application method, CR glove, and coverall weights in the AHS algorithm based on our exposure determinant findings substantially improved the correlation between the AHS algorithm and urinary metabolite levels.
agriculture; captan; dermal exposure—pesticides, determinants of exposure; exposure assessment—mixed models; orchards; pesticide exposure; variance components
Rationale: Associations between oligomeric isocyanate exposure, sensitization, and respiratory disease have received little attention, despite the extensive use of isocyanate oligomers.
Objectives: To investigate exposure–response relationships of respiratory symptoms and sensitization in a large population occupationally exposed to isocyanate oligomers during spray painting.
Methods: The prevalence of respiratory symptoms and sensitization was assessed in 581 workers in the spray-painting industry. Personal exposure was estimated by combining personal task-based inhalatory exposure measurements and time activity information. Specific IgE and IgG to hexamethylene diisocyanate (HDI) were assessed in serum by ImmunoCAP assay and enzyme immunoassays using vapor and liquid phase HDI–human serum albumin (HDI–HSA) and HSA conjugates prepared with oligomeric HDI.
Measurements and Main Results: Respiratory symptoms were more prevalent in exposed workers than among comparison office workers. Log–linear exposure–response associations were found for asthmalike symptoms, chronic obstructive pulmonary disease–like symptoms, and work-related chest tightness (prevalence ratios for an interquartile range increase in exposure of 1.2, 1.3 and 2.0, respectively; P ⩽ 0.05). The prevalence of specific IgE sensitization was low (up to 4.2% in spray painters). Nevertheless, IgE to N100 (oligomeric HDI)–HSA was associated with exposure and work-related chest tightness. The prevalence of specific IgG was higher (2–50.4%) and strongly associated with exposure.
Conclusions: The results provide evidence of exposure–response relationships for both work-related and non–work-related respiratory symptoms and specific sensitization in a population exposed to oligomers of HDI. Specific IgE was found in only a minority of symptomatic individuals. Specific IgG seems to be merely an indicator of exposure.
oligomer; isocyanate; asthma; spray painter; sensitization
Water based paints contain organic solvents and many additives, such as biocides, surfactants, pigments, binders, amines, and monomers. The chemical complexity may introduce new potential health hazards to house painters, in particular irritative and allergic disorders. This study was performed to compare how house painters experience work with water based paints or solvent based paints, and to evaluate whether exposure to water based paints increases mucous membrane and dermal symptoms among house painters. 255 male house painters aged 20 to 65 were invited to participate in the study. Controls were two industrial populations, in total 302 men, without exposure to water based paints. Self administered questionnaires were used to assess the painter's experiences of working with different types of paints and the occurrence of symptoms in the exposed and unexposed groups. Hygiene measurements were performed during normal working days when only water based paints and no solvent based paints were used. The painters were exposed to low concentrations of dust, metals, ammonia, formaldehyde, and volatile organic compounds. The work environment was considered better when working with water based paints than with solvent based paints. There were more complaints of frequent urination when working with water based paint. Taste or olfactory disturbances were less common. General as well as work related eye and skin irritation was more common among the exposed workers. For other symptoms no significant differences were found. The study indicates that the introduction of water based paints has improved the work environment for house painters. Water based paints cause less discomfort and airway irritation than the earlier solvent based paints. Adverse general health effects seem low. Some of the painters may have dermal symptoms caused by the components in water based paints.
We investigated the utility of 1,6-hexamethylene diamine (HDA) hemoglobin adducts as biomarkers of exposure to 1,6-hexamethylene diisocyanate (HDI) monomer. Blood samples from 15 spray painters applying HDI-containing paint were analyzed for hemoglobin HDA (HDA-Hb) and N-acetyl-1,6-hexamethylene diamine (monoacetyl-HDA-Hb) by GC-MS. HDA-Hb was detected in the majority of workers (≤1.2–37 ng/g Hb), whereas monoacetyl-HDA-Hb was detected in one worker (0.06 ng/g Hb). The stronger, positive association between HDA-Hb and cumulative HDI exposure (r2 = 0.3, p < 0.06) than same day exposure (p ≥ 0.13) indicates long-term elimination kinetics for HDA-Hb adducts. This association demonstrates the suitability of HDA-Hb adducts for further validation as a biomarker of HDI exposure.
1,6-hexamethylene diamine (HDA); hemoglobin; adduct; biomarker; 1,6-hexamethylene diisocyanate (HDI)
Bridge painters are exposed to lead during several job tasks performed during the workday, such as sanding, scraping, and blasting. After the Occupational Safety and Health Administration standard was passed in 1993 to control lead exposures among construction workers including bridge painters, this study was conducted among 84 bridge painters in the New England area to determine the significant predictors of blood lead levels. Lead was measured in personal air and hand wipe samples that were collected during the 2-week study period and in blood samples that were collected at the beginning and at the end of the study period. The personal air and hand wipe data as well as personal behaviors (i.e., smoking, washing, wearing a respirator) and work site conditions were analyzed as potential determinants of blood lead levels using linear mixed effects models. Our results show that the mean air lead levels over the 2-week period were the most predictive exposure measure of blood lead levels. Other individual-level significant predictors of blood lead levels included months worked on bridge painting crews, education, and personal hygiene index. Of the site-level variables investigated, having a containment facility on site was a significant predictor of blood lead levels. Our results also indicate that hand wipe lead levels were significantly associated with higher blood lead levels at the end of the study period compared with the beginning of the study period. Similarly, smoking on site and respirator fit testing were significantly associated with higher blood lead levels at the end of the study period. This study shows that several individual-level and site-level factors are associated with blood lead levels among bridge painters, including lead exposure through inhalation and possible hand-to-mouth contact, personal behaviors such as smoking on site, respirator fit testing, and work site conditions such as the use of better containment facilities. Accordingly, reduction in blood lead levels among bridge painters can be achieved by improving these workplace practices.
air lead levels; blood lead levels; bridge painters; hand wipes; lead; work site conditions
Isocyanate chemicals essential for polyurethane production are widely used industrially, and are increasingly found in consumer products. Asthma and other adverse health effects of isocyanates are well-documented and exposure surveillance is crucial to disease prevention. Hexamethylene diisocyanate (HDI)-specific serum immunoglobulin G (IgG) was evaluated as an exposure biomarker among workers at a US Air Force Air Logistics Center, which includes a large aircraft maintenance facility.
HDI-specific IgG (HDI-IgG) titers in serum samples (n = 74) were measured using an enzyme-linked immunosorbent assay based upon the biuret form of HDI conjugated to human albumin. Information on personal protective equipment (PPE), work location/tasks, smoking, asthma history, basic demographics, and HDI skin exposure was obtained through questionnaire.
HDI-specific serum IgG levels were elevated in n = 17 (23%) of the workers studied. The prevalence and/or end-titer of the HDI-IgG was significantly (P < 0.05) associated with specific job titles, self-reported skin exposure, night-shift work, and respirator use, but not atopy, asthma, or other demographic information. The highest titers were localized to specific worksites (C-130 painting), while other worksites (generator painting) had no or few workers with detectable HDI-IgG.
HDI-specific immune responses (IgG) provide a practical biomarker to aid in exposure surveillance and ongoing industrial hygiene efforts. The strategy may supplement current air sampling approaches, which do not assess exposures via skin, or variability in PPE use or effectiveness. The approach may also be applicable to evaluating isocyanate exposures in other settings, and may extend to other chemical allergens.
biomarker; exposure; HDI; hygiene; occupational
OBJECTIVES: To study the role of individual and occupational risk factors for asthma in furniture workers. METHODS: 296 workers were examined (258 men, 38 women) with a questionnaire of respiratory symptoms and diseases, baseline spirometry, bronchial provocative test with methacholine, and skin prick tests. Non-specific bronchial hyperreactivity was defined as when a provocative dose with a fall of 20% in forced expiratory volume in 1 second (PD20FEV1) was < 0.8 mg and atopy in the presence of at least one positive response to skin prick tests. Workers were subdivided into spray painters (exposed to low concentrations of diisocyanates and solvents), woodworkers (exposed to wood dusts), and assemblers (control group). RESULTS: The prevalences of attacks of shortness of breath with wheezing and dyspnoea were higher in spray painters (13.5% and 11.5% respectively) than in woodworkers (7.7% and 6.3%) or in assemblers (1.6% and 1.6%); prevalences of chronic cough, asthma, and rhinitis were also slightly but not significantly higher in spray painters and in woodworkers than in assemblers. The difference in the prevalence of respiratory symptoms among the job titles was due to the atopic subjects, who showed a higher prevalence of chronic cough, wheeze, shortness of breath with wheeze, dyspnoea, and asthma in spray painters than in the other groups. The prevalence of non-specific bronchial hyperreactivity in subjects who performed bronchial provocative tests was 17.7%, with no significant difference among groups. Asthma symptoms were significantly associated with non-specific bronchial hyperreactivity. Asthma-like symptoms plus non-specific bronchial hyperreactivity was found in 4% of assemblers, 10% of woodworkers, and 13.3% of spray painters (chi 2 = 2.6, NS). Multiple logistic analysis taking into account individual (smoke, atopy, age) and occupational (job titles) risk factors confirmed that spray painters had higher prevalence of chronic cough than assemblers, and a trend in increasing the prevalence of shortness of breath with wheeze, dyspnoea, and asthma. CONCLUSIONS: Painters in the furniture industry, particularly atopic subjects, are at higher risk of asthma-like symptoms than other job titles. In these workers asthma-like symptoms are more sensitive than non-specific bronchial hyperreactivity in detecting a negative effect of the occupational exposure.
This article describes methodological approaches for reconstructing long-term occupational exposure to organic solvents among construction painters. A detailed exposure questionnaire was administered to 125 painters to develop a job exposure matrix (JEM). The questionnaire inquired about painting activities with solvent-based paints and use of protection equipment for the previous 25 years in 5-year intervals. Current and historical distributions of solvent air concentrations were assessed for the same time period based on the following information: industrial hygiene measurements, paint composition changes, and VOC emission rate changes from architectural and industrial maintenance coatings. Changes in protection factors of respirators were also assessed. A cumulative solvent exposure index was calculated for each painter through Monte Carlo simulations by combining appropriate input distributions of solvent air concentrations and protection factors of respirators with JEM. Sensitivity simulations revealed that the historical variations in solvent air concentrations had a higher impact on the cumulative solvent exposure index than changes in protection factors for respirators. Fifty-eight percent of painters were classified with a different exposure quartile when the solvent exposure index was used vs. an exposure based only on years using solvent-based paints, suggesting the need for more detailed exposure analysis than just years working when conducting epidemiologic studies for this worker population.
exposure; modeling; organic solvents; painters
To assess the risks of reproductive disorders and birth defects in offspring of male painters with exposure to organic solvents, and to determine the shape of the dose‐response relationship.
Random samples of painters and carpenters were drawn from workers affiliated with the Dutch Trade Union for Construction Workers, the Netherlands, 2001. Information on reproductive outcomes, occupational exposures, and lifestyle habits was retrospectively obtained through self‐administered questionnaires filled in by 398 painters exposed to organic solvents in paints, thinners, and cleansers in the period of three months before the last pregnancy, and 302 carpenters with little or no exposure to solvents. A statistical model was used to estimate quantitative exposure measures.
Workers employed as painters at three months before pregnancy had an increased risk (odds ratio 6.2, 95% CI 1.4 to 27.9) of congenital malformations in offspring compared to carpenters. There was a positive exposure‐response trend with increasing exposure to organic solvents based on quantitative model predicted exposure estimates using toluene as a marker. There was some indication of an increased risk of functional developmental disorders in offspring among painters with intermediate and high model predicted exposure. The risk of low birth weight children seemed to be slightly increased among painters as well. Results for other reproductive outcomes (time to pregnancy, spontaneous abortion, and preterm birth) did not show increased risks.
This study showed a positive association between paternal occupational exposure to organic solvents and congenital malformations in offspring. However, the small numbers of cases, especially when examining different exposure levels, as well as the self‐reported nature of exposure and outcome variables, may hamper interpretation of the results.
paternal exposure; pregnancy; solvents
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.
construction; occupational exposure; oil-based paints; painting; solvents
The association between spray paint exposure and bone remodeling received little attention despite the high usage of spray paints in automobile industries, steel furniture workshops etc.
The present study was aimed at investigating the level of serum markers of bone formation in spray painters. The spray painting subjects were selected from automobile body repair workshops in Chennai region of TamilNadu which constitutes 30% of India's automobile industry.
Setting and Design:
All the study subjects, exposed to spray paint were working in a workshop without standard spraying room and did not wore any aerosol removing respirator. The controls were selected from random population irrespective of occupation. Data relevant to the socioeconomic features and personal history was collected using a questionnaire. The current study included 50 spray painters and 25 control subjects of same age group.
Materials and Methods:
We examined the level of serum calcium, serum phosphorus, serum differentiation markers of bone such as alkaline phosphatase (bone specific) and serum osteocalcin in which these levels were found to be high in serum of spray painters.
The current study concludes dysregulation in bone remodeling of spray painters exposed to chronic solvents and paint pigments.
Bone remodeling; paint pigments; serum markers
Epoxy resin systems have been associated with occupational asthma in several case reports, but medical publications contain little on the potential adverse respiratory effects of these chemicals in exposed worker populations. To further evaluate the association of workplace exposure to epoxy paints and respiratory dysfunction, the cross workshift changes in pulmonary function and symptoms of 32 shipyard painters exposed to epoxy paints were compared with 28 shipyard painters not exposed to epoxy paints. The prevalence of lower respiratory tract symptoms was significantly higher among painters exposed to epoxy paints compared with controls. Among exposed painters the mean cross workshift change in forced expiratory volume in one second (FEV1) (-3.4%) was greater than the decrement in the non-exposed group (-1.4%). A significant linear relation was seen between % decrement in FEV1 and hours of exposure to epoxy paints. This study suggests that epoxy resin coatings as used by shipyard painters are associated with increased lower respiratory tract symptoms and acute decrements in FEV1. Adequate respiratory protection and medical surveillance programmes should be established in workplaces where exposure to epoxy resin systems occurs.
We report a case of a spray painter who developed malignant fibrous histiocytoma (MFH) of the maxillary sinus following long-term exposure to chromium, nickel, and formaldehyde, implying that these agents are probable causal agents of MFH.
The patient developed right-sided prosopalgia that began twenty months ago. The symptom persisted despite medical treatment. After two months, he was diagnosed with MFH through imaging studies, surgery, and pathological microscopic findings at a university hospital in Seoul. His social, medical, and family history was unremarkable.
The patient had worked for about 18 years at an automobile repair shop as a spray painter. During this period, he had been exposed to various occupational agents, such as hexavalent chromium, nickel, and formaldehyde, without appropriate personal protective equipment. He painted 6 days a week and worked for about 8 hours a day.
Investigation of the patient’s work environment detected hexavalent chromium, chromate, nickel, and formaldehyde.
The study revealed that the patient had been exposed to hexavalent chromium, formaldehyde, and nickel compounds through sanding and spray painting. The association between paranasal cancer and exposure to the aforementioned occupational human carcinogens has been established. We suggest, in this case, the possibility that the paint spraying acted as a causal agent for paranasal cancer.
Malignant fibrous histiocytoma; Spray painter; Occupational exposure; Chromium; Nickel; Formaldehyde
OBJECTIVES--To examine if car painters who work with polyurethane paints that contain hexamethylenediisocyanate (HDI) and hexamethylenediisocyanate biuret trimer (HDI-BT) develop acute as well as chronic impairment of lung function. METHODS--In this study data were reanalysed from two earlier studies on a group of car painters to see if a decrease in lung function within the week is a marker of vulnerability in those workers. Data on changes in forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) within the week were available for 20 car painters who were also examined six years later. RESULTS--10 men showed a decline in FVC within the week. There were no significant differences in age, duration of employment, exposures during the follow up period, or smoking between car painters who had decline in lung function within the week and car painters who had not. A significant correlation was found between the change in FVC within the week and the long term (six year) change in FVC, standardised for the effects of aging and smoking, and adjusted for the number of peak exposures. CONCLUSIONS--The results suggest that the decrease in FVC within the week might serve as a guide to identify car painters at risk of a further decrement in lung function above the effects of aging, smoking, and exposure.
Hexamethylene diisocyanate (HDI) is used widely to manufacture polyurethanes for paints and coatings. It is an irritant and a chemical asthmagen. The U.S. Occupational Safety and Health Administration time-weighted average permissible exposure limit is 5 ppb and the ceiling limit is 20 ppb. We sought to develop a sensitive and specific immuno-bioassay to supplement workplace air monitoring and detect recent HDI exposure. For this, we produced rabbit antiserum to HDI-adducted keyhole limpet hemocyanin (HDI-KLH). The specificity of the antiserum was demonstrated by its reaction with a variety of HDI-conjugated proteins and the absence of reactions with conjugates of other diisocyanates, namely toluene diisocyanate and diphenyl methylene diisocyanate. Four immunoassays were developed and compared for their ability to detect decreasing quantities of HDI-adducted human serum albumin (HSA) containing 2 mol HDI adduct per mol HSA (HDI(2)-HSA) as determined by matrix-assisted laser desorption time-of-flight (MALDI-TOF) mass spectrometry. The sensitivities of some of the assays are within the range (0.82-45 nM) of current analytic methods. A Western analysis procedure has a sensitivity of 600 nM HDI adduct on HSA. ELISA inhibition assay, in which microtiter plates are coated with the HDI(2)-HSA antigen, has a sensitivity of 300 nM HDI adduct. An immunoblot assay has a sensitivity of 9 nM HDI adduct. The most sensitive bioassay (1.8 nM HDI adduct) is a three-antibody sandwich ELISA in which wells of microtiter plates are coated with the IgG fraction of the anti-HDI-KLH antisera. Compared with analytic methods for HDI biomonitoring, the immunoassays are faster and less costly and accommodate numerous samples simultaneously. The assays have the potential to affect industrial biomonitoring programs significantly.
OBJECTIVE--This study was undertaken to assess whether contaminated personal clothing worn beneath a coverall (normal workwear) is a source of potentially significant dermal exposure to polycyclic aromatic hydrocarbons (PAHs) in coal liquefaction workers. METHODS--An intervention study was conducted over a two week period involving 10 workers that reflected the range of activities performed at the factory. A cross over design was used to examine the influence of normal workwear (personal clothing worn beneath a coverall) and intervention workwear (new coverall, shirt, trousers, underwear, socks, and boots) upon excretion of urinary 1-hydroxypyrene (1-OHP) and skin pad deposition of pyrene. RESULTS--The impact of intervention was noted in three ways: (1) A notable reduction (55%) in the mass of 1-OHP excreted on the first day of the intervention phase was found. The median reduction in mass excreted (22.7 nmol) was significant from zero at the 5% level; (95% confidence interval (95% CI) 9.5-40.8 nmol). (2) A notable reduction (82%) in skin pad deposition of pyrene on the first day of the intervention phase was found. The median reduction of 13.20 ng.cm-2 was significant from zero at the 5% level; (95% CI 7.3-26.4 ng.cm-2). (3) About a 50% reduction in 1-OHP concentration over the working week occurred during the intervention phase; an increase of 2.07 mumol/mol creatinine was found from the start to the end of the work period during the intervention phase compared with an increase of 4.06 mumol/mol creatinine during the normal phase. This reduction was not significant at the 5% level. CONCLUSION--The results indicate that on the first day of the working week investigated, significant reductions in absorbtion (as measured by excretion of urinary 1-OHP) and deposition of PAHs (as measured by skin pad deposition of pyrene) can be effected by improvements in workwear policy. The impact of the improved workwear regimen was also detected by reduction in spot urinary 1-OHP concentrations, although this effect was less pronounced. One implication of the findings is that exposure to PAHs may arise from workers' own contaminated personal clothing. As a consequence of this study an improved workwear policy has been implemented at the factory.
Background: The authors recently developed a Dermal Exposure Assessment Method (DREAM), an observational semiquantitative method to assess dermal exposures by systematically evaluating exposure determinants using pre-assigned default values.
Aim: To explore the accuracy of the DREAM method by comparing its estimates with quantitative dermal exposure measurements in several occupational settings.
Methods: Occupational hygienists observed workers performing a certain task, whose exposure to chemical agents on skin or clothing was measured quantitatively simultaneously, and filled in the DREAM questionnaire. DREAM estimates were compared with measurement data by estimating Spearman correlation coefficients for each task and for individual observations. In addition, mixed linear regression models were used to study the effect of DREAM estimates on the variability in measured exposures between tasks, between workers, and from day to day.
Results: For skin exposures, spearman correlation coefficients for individual observations ranged from 0.19 to 0.82. DREAM estimates for exposure levels on hands and forearms showed a fixed effect between and within surveys, explaining mainly between-task variance. In general, exposure levels on clothing layer were only predicted in a meaningful way by detailed DREAM estimates, which comprised detailed information on the concentration of the agent in the formulation to which exposure occurred.
Conclusions: The authors expect that the DREAM method can be successfully applied for semiquantitative dermal exposure assessment in epidemiological and occupational hygiene surveys of groups of workers with considerable contrast in dermal exposure levels (variability between groups >1.0). For surveys with less contrasting exposure levels, quantitative dermal exposure measurements are preferable.
A 46-year-old man who had worked as a bumper spray painter in an automobile body shop for 15 years developed lung cancer. The patient was a nonsmoker with no family history of lung cancer. To determine whether the cancer was related to his work environment, we assessed the level of exposure to carcinogens during spray painting, sanding, and heat treatment. The results showed that spray painting with yellow paint increased the concentration of hexavalent chromium in the air to as much as 118.33 μg/m3. Analysis of the paint bulk materials showed that hexavalent chromium was mostly found in the form of lead chromate. Interestingly, strontium chromate was also detected, and the concentration of strontium chromate increased in line with the brightness of the yellow color. Some paints contained about 1% crystalline silica in the form of quartz.
exposure assessment; hexavalent chromium; lung cancer; painting