Biomedical subjects

Hans Kromhout

Publications and source records attributed to Hans Kromhout.

At least 19 recordsLinked to original sources

PubMed2007

Inter-rater agreement in the assessment of exposure to carcinogens in the offshore petroleum industry.

OBJECTIVES: To evaluate the reliability of an expert team assessing exposure to carcinogens in the offshore petroleum industry and to study how the information provided influenced the agreement among raters. METHODS: Eight experts individually assessed the likelihood of exposure for combinations of 17 carcinogens, 27 job categories and four time periods (1970-1979, 1980-1989, 1990-1999 and 2000-2005). Each rater assessed 1836 combinations based on summary documents on carcinogenic agents, which included descriptions of sources of exposure and products, descriptions of work processes carried out within the different job categories, and monitoring data. Inter-rater agreement was calculated using Cohen's kappa index and single and average score intraclass correlation coefficients (ICC) (ICC(2,1) and ICC(2,8), respectively). Differences in inter-rater agreement for time periods, raters, International Agency for Research on Cancer groups and the amount of information provided were consequently studied. RESULTS: Overall, 18% of the combinations were denoted as possible exposure, and 14% scored probable exposure. Stratified by the 17 carcinogenic agents, the probable exposure prevalence ranged from 3.8% for refractory ceramic fibres to 30% for crude oil. Overall mean kappa was 0.42 (ICC(2,1) = 0.62 and ICC(2,8) = 0.93). Providing limited quantitative measurement data was associated with less agreement than for equally well described carcinogens without sampling data. CONCLUSION: The overall kappa and single-score ICC indicate that the raters agree on exposure estimates well above the chance level. The levels of inter-rater agreement were higher than in other comparable studies. The average score ICC indicates reliable mean estimates and implies that sufficient raters were involved. The raters seemed to have enough documentation on which to base their estimates, but provision of limited monitoring data leads to more incongruence among raters. Having real exposure data, with the inherent variability of such data, apparently makes estimating exposure in a rigid semiquantitative manner more difficult.

Carcinogens↗

PubMed2007

Nurses with dermal exposure to antineoplastic drugs: reproductive outcomes.

BACKGROUND: Nurses and other hospital workers are exposed to antineoplastic drugs during daily activities. Previous studies suggest that antineoplastic drugs at occupational exposure levels may be toxic to reproduction, but these studies are not consistent or conclusive. METHODS: Self-administered questionnaires were completed by 4393 exposed and nonexposed nurses employed between 1990 and 1997 (79% response). Questions were asked about pregnancy outcome, work-related exposures, and lifestyle. Exposure to antineoplastic drugs was estimated using task-based dermal exposure measurements and self-reported task frequencies. Time to pregnancy was modeled using survival analysis, and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for other reproductive outcomes using multiple logistic regression analysis. Associations were further explored by nonparametric regression modeling. RESULTS: Nurses highly exposed to antineoplastic drugs took longer to conceive than referent nurses (adjusted hazard ratio = 0.8; CI = 0.6-0.9). Exposure to antineoplastic drugs was associated with premature delivery (OR per unit increase in ln[exposure] = 1.08; CI = 1.00-1.17) and low birth weight (OR per unit increase in ln[exposure] = 1.11; 1.01-1.21). Penalized smoothed spline plots corroborated these log-linear relations. Spontaneous abortion, stillbirth, congenital anomalies, and sex of offspring appeared not to be related to exposure to antineoplastic drugs. CONCLUSION: Antineoplastic drugs may reduce fertility and increase poor neonatal outcomes among occupationally exposed oncology nurses.

Adult↗

PubMed2006

Exposure to wood dust among carpenters in the construction industry in the Netherlands.

Exposure to wood dust was measured among 26 carpenters at 13 building projects. Sampling days were chosen randomly. Individual tasks, based on technology applied and material used during a working day, were sampled separately. From these task-based measurements, 8 h time-weighted average concentrations were calculated. Sampling was performed in accordance with a protocol that was developed by the carpentry and furniture industry and which was especially designed for sampling of wood dust. Eight hours time-weighted average exposure to wood dust ranged from 0.8 to 11.6 mg m(-3) with a geometric mean (GM) of 3.3 mg m(-3) and a geometric standard deviation (GSD) of 2.1. The probability of exceedance of the OEL, when comparing the estimated concentrations against the Dutch OEL of 2 mg m(-3), was 75%. The highest exposures were measured during sawing of Cempanel sheets. Task-based measurements showed lowest exposures when working outdoors (n = 11, AM = 2.2 mg m(-3)), but even then 5 out of 11 task-based exposures exceeded 2 mg m(-3). Indoors the exposure was 5.2 mg m(-3) (AM, n = 29) and when working both indoors and outdoors exposure was 16.2 mg m(-3) (AM, n = 4). In conclusion, long-term average exposure to wood dust among carpenters at construction sites is more than 1.5 times the present occupational exposure limit of 2 mg m(-3). The estimated probability of exceedance of the OEL was 75% and a reduction of exposure with a factor 5 is needed to bring the probability of exceedance below 5%. It is intended to lower the exposure limit to 1 mg m(-3) by 1 January 2007. In that case the probability of exceedance of the OEL is 95% and a reduction of exposure with a factor 10 is needed to bring the probability of exceedance below 5%. This can be achieved by using alternative materials, preparation of building material in workshops equipped with exposure controls, alternative equipment and improved ventilation and good housekeeping.

Air Pollution, Indoor↗

PubMed2006

Inhalation and dermal exposure to eight antineoplastic drugs in an industrial laundry facility.

OBJECTIVES: The aims of the study were to quantify levels of dermal and inhalation exposure to antineoplastic drugs in an industrial laundry service in the Netherlands and to test the removal efficiency of the washing procedure for removal of antineoplastic drugs. METHODS: During four workdays dermal and inhalation exposure to eight frequently used antineoplastic drugs (cyclophosphamide, ifosfamide, methotrexate, 5-fluorouracil, etoposide, cytarabine, gemcitabine and chlorambucil) were measured for all job titles involved in handling unwashed laundry. To test the removal efficiency of the washing procedure, 10 x 10 cm sections were excised before and after the washing procedure. These sections were taken from 15 bed sheets that were collected in hospitals of patients who were treated with one of the selected antineoplastic drugs. RESULTS: During none of the four measurement days, detectable levels of any of the eight antineoplastic drugs (cyclophosphamide, ifosfamide, methotrexate, 5-fluorouracil, etoposide, cytarabine, gemcitabine, or chlorambucil) were found on workers' skin of hands or in any of the air samples. Only four out of the 15 bed sheets from patients that were treated with antineoplastic drugs appeared to be contaminated with detectable levels of antineoplastic drugs before the washing procedure (range 13.0-3,060 ng/100 cm(2)). After the pre-washing and after the complete washing procedure, no detectable levels of any of the eight antineoplastic drugs were found anymore in the selected bed sheets. CONCLUSIONS: The implementation of guidelines for working with antineoplastic drugs seems to be successful in reducing exposure to antineoplastic drugs of workers in this laundry facility to an acceptable, non-detectable level and to remove antineoplastic drug contamination from bed linen.

Antineoplastic Agents↗

PubMed2006

Urinary pesticide concentrations among children, mothers and fathers living in farm and non-farm households in iowa.

In the spring and summer of 2001, 47 fathers, 48 mothers and 117 children of Iowa farm and non-farm households were recruited to participate in a study investigating take-home pesticide exposure. On two occasions approximately 1 month apart, urine samples from each participant and dust samples from various rooms were collected from each household and were analyzed for atrazine, metolachlor, glyphosate and chlorpyrifos or their metabolites. The adjusted geometric mean (GM) level of the urine metabolite of atrazine was significantly higher in fathers, mothers and children from farm households compared with those from non-farm households (P < or = 0.0001). Urine metabolites of chlorpyrifos were significantly higher in farm fathers (P = 0.02) and marginally higher in farm mothers (P = 0.05) when compared with non-farm fathers and mothers, but metolachlor and glyphosate levels were similar between the two groups. GM levels of the urinary metabolites for chlorpyrifos, metolachlor and glyphosate were not significantly different between farm children and non-farm children. Farm children had significantly higher urinary atrazine and chlorpyrifos levels (P = 0.03 and P = 0.03 respectively) when these pesticides were applied by their fathers prior to sample collection than those of farm children where these pesticides were not recently applied. Urinary metabolite concentration was positively associated with pesticide dust concentration in the homes for all pesticides except atrazine in farm mothers; however, the associations were generally not significant. There were generally good correlations for urinary metabolite levels among members of the same family.

Acetamides↗

PubMed2006

Occupational exposure to inhalable wood dust in the member states of the European Union.

The aim of this study was to estimate occupational exposure to inhalable wood dust by country, industry, the level of exposure and type of wood dust in 25 member states of the European Union (EU-25) for the purposes of hazard control, exposure surveillance and assessment of health risks. National labour force statistics, a country questionnaire (in 15 member states, EU-15), a company survey (in Finland, France, Germany and Spain), exposure measurements (from Denmark, Finland, France, Germany, The Netherlands and the United Kingdom) and expert judgements were used to generate preliminary estimates of exposure to different types of wood dust. The estimates were generated according to industrial class (six wood industries, four other sectors) and level of exposure (five classes). These estimates were reviewed and finalized by national experts from 15 member states. Crude estimates were generated also for 10 new member states (EU-10). The basic data and final estimates were included in the WOODEX database. In 2000-2003, about 3.6 million workers (2.0% of the employed EU-25 population) were occupationally exposed to inhalable wood dust. Of those, construction employed 1.2 million exposed workers (33%), mostly construction carpenters. The numbers of exposed workers were 700,000 (20%) in the furniture industry, 300,000 (9%) in the manufacture of builders' carpentry, 200,000 (5%) in sawmilling, 150,000 (4%) in forestry and <100,000 in other wood industries. In addition, there were 700,000 exposed workers (20%) in miscellaneous industries employing carpenters, joiners and other woodworkers. The numbers of exposed workers varied by country ranging from <3,000 in Luxembourg and Malta to 700,000 in Germany. The highest exposure levels were estimated to occur in the construction sector and furniture industry. Due to limited exposure data there was considerable uncertainty in the estimates concerning construction woodworkers. About 560,000 workers (16% of the exposed) may be exposed to a level exceeding 5 mg m(-3). Mixed exposure to more than one species of wood and dust from wooden boards was very common, but reliable data on exposure to different species of wood could not be retrieved. This kind of assessment procedure integrating measurement data, company data, country-specific data and expert judgement could also serve as one model for the assessment of other occupational exposures.

Air Pollutants, Occupational↗

PubMed2006

Field comparison of inhalable aerosol samplers applied in the european rubber manufacturing industry.

Several studies have been done in Europe to evaluate exposure to dust and fumes in the rubber industry. However, different aerosol sampling devices have been used which perform differently depending on the environmental conditions and particle size distribution. To compare measurements of rubber dust and fumes among countries and surveys we initiated a field comparison of personal inhalable samplers using a novel reference inhalable aerosol sampler (CALTOOL). Measurements were done in four factories in the Netherlands, Sweden, Poland and Germany in the mixing and milling and curing department. The Seven-hole sampler, PAS-6 sampler, Millipore (25 and 37 mm) cassette, IOM sampler and a Polish sampler were mounted on the reference CALTOOL device and used simultaneously. All samplers except the IOM sampler under-sampled inhalable dust. To compare measurements from different studies and countries, correction factors should be applied to all but the IOM sampler, which was the only sampler that performed similar to the CALTOOL sampler.

Aerosols↗

PubMed2006

Exposure, health complaints and cognitive performance among employees of an MRI scanners manufacturing department.

PURPOSE: To assess sensory effects and other health complaints that are reported by system testers working near magnetic resonance imaging (MRI) magnets, realizing that it is believed that exposure up to 8 T is safe for humans. MATERIALS AND METHODS: Levels of exposure to static magnetic fields (SMFs), movement speed during exposure, health complaints, and cognitive performance among employees in an MRI-manufacturing department and at a reference department have been analyzed. Mercury concentrations in urine samples were determined to analyze whether they depend on exposure to SMFs. RESULTS: Average exposure of system testers was 25.9 mT/8 hours at a 1.0-T system and 40.4 mT/8 hours at a 1.5-T system. Vertigo, metallic taste, and concentration problems were more reported among workers of MRI-fabrication than in the reference department. Cognitive performance was tested outside the SMF, and no significant changes were detected. CONCLUSION: This study suggests that any effects on cognitive functions are acute and transient and disappear rapidly after exposure has ended. All complaints, except for headaches, were more frequently reported by "fast movers" than by "slow movers," and depended on field strength and duration of exposure. Mercury-levels in urine were not affected.

Cognition Disorders↗

PubMed2006

Acute neurobehavioral effects of exposure to static magnetic fields: analyses of exposure-response relations.

PURPOSE: To assess exposure-response relations between exposure to magnetic fields and neurobehavioral effects. MATERIALS AND METHODS: Twenty company volunteers completed a neurobehavioral test battery after they moved their heads with the magnetic field absent, and while they moved their heads in the inhomogenous stray fields of 1.5 and 3.0 T MRI magnets. RESULTS: The value of the stray fields at the position of the head of the volunteer was estimated to be 0.6 T and 1.0 T on the 1.5 T and 3.0 T systems, respectively. Exposure-response relations were found for visual (-2.1%/100 mT) and auditory (-1.0%/100 mT) working memory, eye-hand coordination speed (-1.0%/100 mT), and visual tracking tasks (-3.1%/100 mT). Eye-hand precision, scanning speed, and visual contrast sensitivity were apparently not influenced by the magnetic field strength. CONCLUSION: Additional research should focus on the potential side effects of interventional MR procedures because of the exposure to strong magnetic fields of these systems.

Adult↗

PubMed2005

Biological monitoring of carbon disulphide and phthalate exposure in the contemporary rubber industry.

OBJECTIVES: We studied the range in urinary levels of 2-thiothiazolidine-4-carboxyl acid (TTCA), a metabolite of CS2 and phthalic acid (PA), a common metabolite of phthalates, across factories and departments in the contemporary rubber manufacturing industry. METHODS: Spot urine samples from 101 rubber workers employed in nine different factories were collected on Sunday and during the workweek on Tuesday, Wednesday and Thursday at approximately 4 pm. In total, 386 urine samples were successfully analyzed. RESULTS: Levels of both biomarkers increased significantly by a factor 2 (paired t-test P-value <0.05) during the working week as compared to the Sunday biomarker levels with absolute increases of approximately 70 microg/l and 5 micromol/mol creatinine for PA and TTCA, respectively. Levels in both biomarkers did not differ markedly between working days. Increases seemed to be restricted to specific factories and/or departments (e.g. molding and curing). CONCLUSIONS: The results of this study demonstrate that rubber workers in the contemporary rubber industry are exposed to phthalates and low levels of CS2 ( approximately 0.05 ppm) as measured by PA and TTCA, respectively. Exposures to both compounds are largely driven by specific circumstances in factories. Therefore, when estimating exposures to phthalates and CS2 detailed information should be collected on the type and amount of phthalate containing ester plasticizers, dithiocarbamates and thiurams used. Preferably, personal exposure data should be collected. In this case, biological monitoring seems a reasonable approach. However, in the case of PA attention should be given to individual background levels as this could lead to a substantial overestimation of the occupational contribution to total phthalate exposure.

Air Pollutants, Occupational↗

PubMed2005

A database of exposures in the rubber manufacturing industry: design and quality control.

The concerted action EXASRUB was initiated to create a database management system for information on occupational hygiene measurements that could be used to develop exposure models in the European rubber manufacturing industry. Quality of coding was assessed by calculating percentages of agreement and Cohen's kappa statistics (kappa) for an intra- and inter-centre recoding of randomly selected subsets of the measurements. In a 6-month period, 59 609 measurements from 523 surveys in 333 factories from as early as 1956 to 2003 were coded. The database consists primarily of measurements of N-nitrosamines (36%), rubber dust (23%), solvents (14%) and rubber fumes (10%). Coding of epidemiologically relevant information was done consistently with inter-centre kappa between 0.86 and 1.00. For occupational hygiene information, values of kappa were estimated to be between 0.67 and 1.00. The proposed method resulted in a large quantity of exposure measurements with auxiliary information of varying completeness and quality. Analyses showed that coding of epidemiologically relevant information in such a multi-centre, multi-country study was coded consistently. Larger errors however, occurred in coding of occupational hygiene information. This was primarily caused by lack of information in the primary records of measurements, emphasizing the importance of having a universal system in place to collect and store measurement information by occupational hygienists for future use.

Chemical Industry↗

PubMed2005

Are variance components of exposure heterogeneous between time periods and factories in the European carbon black industry?

Occupational exposure to chemical agents can vary enormously within- and between-workers, even when carrying out the same jobs. When repeated measurements are available, the variance components can be estimated using random- or mixed-effects models. Pooling the variance components across the fixed effects, in mixed-effects models, reduces the complexity of the models; especially, when there are a large number of fixed effects. The analyses presented in this paper tested the assumptions of homogeneity in the variance components between factories and surveys for inhalable dust exposure in the European carbon black manufacturing industry. In total, 5296 measurements from 1771 workers were available collected during two surveys carried out between 1991 and 1995. Workers were grouped into eight job categories, and for each of these separate mixed-effects models were developed, including factory, survey and in some cases the interaction term as the fixed effects. The likelihood ratio test was used to test the assumptions of homogeneity of the variance components. Statistically significant heterogeneity of the variance components was observed for two of the eight job categories, 'Fitter/Welder' and 'Warehouseman'. The heterogeneity was due mainly to differences in variance between the factories. When estimating the probability of overexposure for all the factories combined, there was little difference between the models with and without heterogeneous variance components for 'Fitters/Welders'. For the 'Warehousemen' the probability of overexposure in the last survey changed marginally from 4% in the pooled model to 6% in the heterogeneous model. Larger differences between the models were observed when estimating the probability of overexposure for individual factories, which was due to over- or under-estimation of the variance components in the pooled models. In conclusion, for most job categories pooling of the variance components appears to be justified in this database. In addition, no large differences were found when determining the industry-wide probability of 'overexposure' when comparing the pooled with the heterogeneous models. However, when evaluating the factory-specific probability of 'overexposure' or when using the models to provide exposure estimates for epidemiological studies heterogeneity in the variance components should be investigated.

Analysis of Variance↗

PubMed2005

Lung function decline, chronic bronchitis, and occupational exposures in young adults.

RATIONALE: Occupational exposures to vapors, gas, dust, or fumes have been shown to be a risk factor of airway obstruction in cross-sectional studies in the general population. OBJECTIVES: Our aim was to study the relationships between specific occupations and occupational exposures during a 9-yr follow-up period and changes in lung function and symptoms of chronic bronchitis. METHODS: Subjects from the general population aged 20 to 45 yr were randomly selected in 1991-1993 within the European Community Respiratory Health Survey. Follow-up took place from 1998 to 2002 among 4,079 males and 4,461 females in 27 study centers. A total of 3,202 men and 3,279 women twice completed lung function measurements. Job history during follow-up was linked to a job exposure matrix and consequently translated into cumulative exposure estimates. MAIN RESULTS: Individuals exposed to dusts, gases, and fumes during the period of follow-up did not have a steeper decline of FEV1 than did individuals with consistently white-collar occupations without occupational exposures (relative change among men and women, + 1.4 and -3.1 ml/yr, respectively; p > 0.2), nor an increase of prevalence or incidence of airway obstruction defined as an FEV1/FVC ratio of less than 0.7. The incidence of chronic phlegm increased in men exposed to mineral dust (relative risk, 1.94 [1.29-2.91]) and gases and fumes (relative risk, 1.53 [0.99-2.36]), which was not modified by smoking. CONCLUSION: Occupational exposures to dusts, gases, and fumes occurring during the 1990s are associated with incidence of chronic bronchitis, although these did not impair lung function in a population of relatively young age.

Adult↗

PubMed2005

Dermal exposure to cyclophosphamide in hospitals during preparation, nursing and cleaning activities.

OBJECTIVES: To determine levels of potential and actual dermal exposure to cyclophosphamide (CP) during performance of oncology-related tasks in hospitals and to investigate the relationship with potential sources and surface contamination levels of CP. METHODS: Dermal exposure to CP was determined for tasks with potential exposure to CP: preparation of CP, decanting of patients' urine, washing of the patient, removal of bed sheets of treated patients and cleaning of patients' toilets on oncology wards. Exposure was assessed by the collection of nitrile and latex protective medical gloves (potential exposure), washing of hands (actual exposure), from cotton pads attached to (un)covered forearms (potential or actual exposure) and a wipe sample of the forehead (actual exposure). Bulk samples (i.e. application fluids and patients' excreta) and possible contact surfaces were monitored to assess the amount of CP available for dermal exposure. RESULTS: Pharmacy technicians, oncology nurses and cleaning personnel showed actual and potential dermal exposure to CP during performance of their daily duties. Exposure occurred predominantly on the hands and sporadically on the forehead and forearms. Although all nurses used gloves during handling of patients' urine and sometimes during the other nursing tasks, skin underneath gloves was repeatedly contaminated. Results of tests on bulk and surface contamination samples confirmed that patients intravenously treated with CP excrete the unmetabolised drug, which could subsequently lead to dermal exposure of hospital personnel. A clear relationship was found between dermal exposure levels and direct sources of exposure for all tasks, except for handling patients' urine. CONCLUSIONS: We demonstrated for the first time that actual dermal exposure to CP is common among oncology nurses working with patients treated with this anti-neoplastic drug. Pharmacy technicians and cleaning personnel, on the other hand, are potentially exposed to CP, and protection provided by gloves seemed to be sufficient.

Antineoplastic Agents, Alkylating↗

PubMed2005

Comparison of self-reported occupational exposure with a job exposure matrix in an international community-based study on asthma.

BACKGROUND: Self-reports are frequently used to assess occupational exposures in epidemiological studies on asthma, but the validity and influence of asthma status on performance is unclear. METHODS: Data on self-reported exposure to air pollutants were obtained for 16,752 randomly selected working individuals from 40 study centers, and compared to exposures obtained by a job exposure matrix (JEM). The influence of current asthma symptoms or medication was investigated. RESULTS: Specificity of self-reports amounted to 0.83 and 0.87, and sensitivity 0.48 and 0.42 for asthmatics and non-asthmatics, respectively, when compared with the JEM. Self-reported exposure, but not exposure assessed by the JEM, was more prevalent in areas with a higher community prevalence of asthma. CONCLUSIONS: The prevalence of self-reported occupational exposures seems to depend on asthmatic health status at both the individual and the community level. Associations between self-reports and asthma are likely to be biased, especially in pooled analyses combining different areas with varying prevalence rates of asthma.

Adult↗

PubMed2005

Dermal exposure assessment to benzene and toluene using charcoal cloth pads.

Charcoal cloth pads have been used to assess volatile chemicals on the skin in a laboratory setting; however, they have not yet been applied to measure dermal exposure in occupational settings. This study aimed at evaluating whether charcoal pads can be used to assess dermal exposure to benzene and toluene in workers of a petrochemical plant. Inhalation and dermal exposure levels to benzene and toluene were assessed for workers of a petrochemical plant performing different jobs. Benzene uptake was assessed by determining S-phenylmercapturic acid in workers' urine samples. Dermal exposure levels on the charcoal pads were adjusted for ambient air levels of benzene and toluene by subtracting the amount of benzene or toluene measured in personal air from the amount of benzene or toluene measured on the charcoal pad. In general, measured external and internal exposure levels were low. The estimated contribution of the dermal route to internal benzene exposure levels was less than 0.06% for all jobs. Toluene personal air concentrations and benzene and toluene dermal exposure levels differed statistically significantly between job titles. For benzene, differences between jobs were larger for adjusted dermal exposures (maximum 17-fold, P = 0.02) than for inhalation exposures (maximum two-fold, P = 0.08). Also for toluene, although less clear, differences between jobs were larger for adjusted dermal exposures (maximum 23-fold, P = 0.01) as compared to inhalation exposures (maximum 10-fold, P = 0.01). Charcoal pads appeared to measure dermal exposures to benzene and toluene in addition to ambient air levels. Future studies applying charcoal cloth pads for the dermal exposure assessment at workplaces with higher dermal exposure to organic solvents may provide more insight into the biological relevance of dermal exposure levels measured by charcoal cloth pads. In addition, the design of the dermal sampler might be improved by configuring a dermal sampler, where part of the sampler is protected against direct contact and splashes, but still permeable for the gas phase. This design would most likely result in a better ability to correct for airborne concentrations at a given body location.

Administration, Cutaneous↗

PubMed2005

Reliability of a semi-quantitative method for dermal exposure assessment (DREAM).

Valid and reliable semi-quantitative dermal exposure assessment methods for epidemiological research and for occupational hygiene practice, applicable for different chemical agents, are practically nonexistent. The aim of this study was to assess the reliability of a recently developed semi-quantitative dermal exposure assessment method (DREAM) by (i) studying inter-observer agreement, (ii) assessing the effect of individual observers on dermal exposure estimates for different tasks, and (iii) comparing inter-observer agreement for ranking of body parts according to their exposure level. Four studies were performed in which a total of 29 observers (mainly occupational hygienists) were asked to fill in DREAM while performing side-by-side observations for different tasks, comprising dermal exposures to liquids, solids, and vapors. Intra-class correlation coefficients ranged from 0.68 to 0.87 for total dermal exposure estimates, indicating good to excellent inter-observer agreement. The effects of individual observers on task estimates were estimated using a linear mixed effect model with logged DREAM estimates as explanatory variable; "task", "company/department", and the interaction of "task" and "company/department" as fixed effects; and "observer" as a random effect. Geometric mean (GM) dermal exposure estimates for different tasks were estimated by taking the exponent of the predicted betas for the tasks. By taking the exponent of the predicted observer's intercept (exp(omega i)), a multiplier (M(O)) was estimated for each observer. The effects of individual observers on task estimates were relatively small, as the maximum predicted mean observers' multiplier was only a factor 2, while predicted GMs of dermal exposure estimates for tasks ranged from 0 to 1226, and none of the predicted individual observers' multipliers differed significantly from 1 (t-test alpha = 0.05). Inter-observer agreement for ranking of dermal exposure of nine body parts was moderate to good, as median values of Spearman correlation coefficients for pairs of observers ranged from 0.29 to 0.93. DREAM provides reproducible results for a broad range of tasks with dermal exposures to liquids, solids, as well as vapors. DREAM appears to offer a useful advance for estimations of dermal exposure both for epidemiological research and for occupational hygiene practice.

Administration, Cutaneous↗

PubMed2005

Polycyclic aromatic hydrocarbons and fatal ischemic heart disease.

BACKGROUND: Several toxicologic and epidemiologic studies have produced evidence that occupational exposure to polycyclic aromatic hydrocarbons (PAH) is a risk factor for ischemic heart disease (IHD). However, a clear exposure-response relation has not been demonstrated. METHODS: We studied a relation between exposure to PAH and mortality from IHD (418 cases) in a cohort of 12,367 male asphalt workers from Denmark, Finland, France, Germany, Israel, The Netherlands and Norway. The earliest follow up (country-specific) started in 1953 and the latest ended in 2000, averaging 17 years. Exposures to benzo(a)pyrene were assessed quantitatively using measurement-driven exposure models. Exposure to coal tar was assessed in a semiquantitative manner on the basis of information supplied by company representatives. We carried out sensitivity analyses to assess potential confounding by tobacco smoking. RESULTS: Both cumulative and average exposure indices for benzo(a)pyrene were positively associated with mortality from IHD. The highest relative risk for fatal IHD was observed for average benzo(a)pyrene exposures of 273 ng/m or higher, for which the relative risk was 1.64 (95% confidence interval=1.13-2.38). Similar results were obtained for coal tar exposure. Sensitivity analysis indicated that even in a realistic scenario of confounding by smoking, we would observe approximately 20% to 40% excess risk in IHD in the highest PAH-exposure categories. CONCLUSIONS: Our results lend support to the hypothesis that occupational PAH exposure causes fatal IHD and demonstrate a consistent exposure-response relation for this association.

Cause of Death↗