Skin exposure to epoxy chemicals in construction coating, assessed by observation, interviews, and measurements.

BACKGROUND: Epoxy resin systems (ERSs) are among the leading causes of occupational allergic contact dermatitis. OBJECTIVES: To identify riskful exposures and sources of skin exposure, and to quantify skin exposure to diglycidyl ether of bisphenol A (DGEBA) epoxy monomer, in construction coating work. METHODS: Skin exposure to epoxy chemicals was studied in 5 coating companies through (a) interviews and visual observation, (b) quantifying DGEBA on 12 workers' skin by tape-stripping, (c) measuring DGEBA on 23 surfaces by wipe-sampling, and (d) quantifying DGEBA in new sewage pipe. Acetone extracts of the tapes, wipes and sawdust from a newly hardened sewage pipe were analysed by gas chromatography/mass spectrometry. RESULTS: Identified riskful exposures were, for example, mixing ERSs, handling coating pots, and working above shoulder level. Epoxy stains on, for example, tools, equipment and clothing were seen in all workplaces. Protective gloves were of varying quality, and were not always suitable for chemicals. The amount of DGEBA on the workers' skin varied considerably. All screened tool handles were contaminated. Two-day-old epoxy sewage pipe contained 3.2% DGEBA. CONCLUSIONS: Construction coating entails skin contact with ERSs directly and via contaminated surfaces, personal protective equipment, and recently hardened epoxy materials. Observation is a useful method for assessing skin exposure in coating work.

Detecting chronic solvent encephalopathy in occupations at risk.

Chronic solvent encephalopathy (CSE) is under-reported worldwide due to difficulties in recognition and differences in national legislation. Although its occurrence in developed countries has declined, new cases continue to be detected. Our aim was to determine whether CSE can be detected in risk trades, using a stepwise screening procedure. Another aim was to evaluate if this method detects more cases than present occupational health service (OHS) practices do in Finland, a country with decreasing exposures, high OHS coverage and an annual rate of around forty cases of suspected CSE and seven cases of occupational CSE. The studied fields, based on the national occurrence of CSE, were industrial and construction painting, floor layering, the printing press industry, boat construction, reinforced plastic laminating and the metal industry. We obtained contact information from trade union registers and municipal OHS. A postal survey including the Euroquest (EQ) neurotoxic symptom questionnaire, Beck's Depression Inventory (BDI) and the Alcohol Use Disorders Identification Test-Consumption (Audit-C), and questions on exposure and medical conditions, was sent to 3,640 workers in the age range of 30-65 years in two Finnish provinces. The survey resulted in 1,730 responses (48%). This was followed by a clinical examination, with methods applicable to OHS, of subjects fulfilling the criteria: three or more EQ memory and concentration symptoms and sufficient exposure, a BDI score≤18, an AUDIT-C score≤8, and no evident medical condition explaining their symptoms. Of 338 respondents with memory and concentration symptoms, 129 subjects fulfilled all the criteria, of which 83 participated in clinical examinations. We found 38 CSE compatible cases. The study shows that more CSE compatible cases can be detected when the screening is directed towards the occupational fields at greatest risk. This stepwise method is more effective for finding CSE compatible cases than regular OHS activity. The number of cases was similar to the total annual occurrence, of new CSE-suspected cases, although the sample represented approximately 18% of the abundantly exposed workforce in Finland. Combining of exposure and medical differential diagnostics to neurotoxic symptom questionnaire, decreases the amount of cases needing clinical examinations. This two-step procedure can be carried out with methods suitable for OHS and other primary health care, both in industrialized and developed countries.

Airborne concentrations of volatile organic compounds, formaldehyde and ammonia in Finnish office buildings with suspected indoor air problems.

A database of indoor air concentrations of volatile organic compounds (VOCs) (n = 528), formaldehyde (n = 76), and ammonia (n = 47) in office environments was analyzed to suggest interpretation guidelines for chemical measurements in office buildings with suspected indoor air problems. Indoor air samples were collected for VOCs from 176 office buildings, 23 offices for formaldehyde, and 14 office buildings for ammonia in 2001-2006. Although the buildings had reported indoor air complaints, a walk-through inspection by indoor air specialists showed no exceptional sources of indoor air pollutants. The measurements of chemical pollutants did not indicate any clear reason for the complaints. The geometric mean concentration of total volatile organic compounds (TVOC) was 88 microg m(-3) in office rooms and 75 microg m(-3) in the open plan offices. The mechanical supply and exhaust ventilation significantly (p < 0.004) decreased the indoor air concentration of TVOC. The highest mean concentration and frequency distributions were determined for the individual VOCs. The most common VOCs found in > or = 84% of the indoor samples include toluene, xylene (p,m), 1-butanol, nonanal, and benzene. According to concentrations, the most abundant VOCs were 2-(2-ethoxyethoxy)ethanol, acetic acid, 1,2-propanediol, and toluene. The geometric mean concentration of formaldehyde and ammonia in the office buildings was 11 microg m(-3) (3-44 microg m(-3) and 14 microg m(-3) (1-49 microg m(-3), respectively. On the basis of statistical analyses, the guideline value indicating a usual concentration of the pollutant in office buildings is 70 microg m(-3) for TVOC, 7 microg m(-3) for most individual VOCs, 10 microg m(-3) for formaldehyde, and 12 microg m(-3) for ammonia. The guidance value suggested for TVOC is 250 microg m(-3), for formaldehyde 15 microg m(-3), and for ammonia 25 microg m(-3). If the guidance value is exceeded, this may indicate the existence of an exceptional source and the need for additional environmental investigations. The levels should not be used for the evaluation of health risks. The guideline values are applicable in a subarctic climate for modern, urban office buildings.

Quantitative risk assessment in relation to occupational exposure to polychlorinated biphenyls in the removal of old sealants from buildings.

OBJECTIVES: The objectives of the study were to assess exposure to polychlorinated biphenyls (PCB) among workers involved in the removal of old sealants containing PCB and to evaluate the related long-term health risks by means of quantitative risk assessment. METHODS: Workers' exposure via different exposure routes was estimated from air and material samples and exposure calculations. The health risks were evaluated using unit risks and a reference dose based on animal tests and evaluations made by the Environmental Protection Agency in the United States. RESULTS: The estimated exposure of the workers was higher than that of the general population. It was about 10-fold higher than the reference dose and average dietary intake (both 0.02 microg/kg-day). The calculated point estimate of excess cancer risk was 4.6 x 10(-4) cancer cases per lifetime. CONCLUSIONS: The estimated excess cancer risk among workers was low, although the PCB exposure of these workers was higher than the dietary intake of the general population. This quantitative risk assessment method can be used to evaluate the health risk of groups of workers by occupational health professionals.

Worker exposure to polychlorinated biphenyls in elastic polysulphide sealant renovation.

Worker exposure to polychlorinated biphenyls (PCBs) in renovation of prefabricated houses was assessed by biological monitoring of 24 PCB congeners including the 10 most abundant PCBs in elastic polysulphide sealants. Serum samples from 22 exposed and 21 non-exposed men were analysed using gas chromatography-mass spectrometry with negative chemical ionization. Total PCB concentration of 24 PCB congeners in workers' serum varied between 0.6 and 17.8 microg/l (mean 3.9 microg/l, median 1.9 microg/l). The Finnish upper reference limit for occupationally non-exposed persons (3 microg/l) was exceeded in the serum samples of 10 workers. Concentrations for non-exposed persons were 0.3-3.0 microg/l (mean 1.7 microg/l, median 1.5 microg/l). The concentration for the sum of the 10 most abundant PCB congeners in elastic polysulphide sealants in serum samples taken in autumn after the renovation season was 2-10 times higher than in samples from the same workers (n=5) taken in the previous spring. The concentrations of PCB congeners PCB 28, 52, 77, 101, 138, 153 and 180 in hygienic samples taken from the breathing zone of the workers were low, ranging from not detected to 3.1 microg/m3. The concentrations of PCB 28 and 52 in sera were positively correlated with the concentrations in air samples taken from the breathing zone of six workers (r=0.70 and 0.80).