American Industrial Hygiene Conference and Exposition, May 19-23, 1997, Dallas, Texas. Fairfax, VA: American Industrial Hygiene Association, 1997 May; :76-77
The National Institute for Occupational Safety and Health (NIOSH) and the United States Forest Service (USFS) is currently conducting an epidemiologic study to assess the potential that exposures to tree-marking paint might be causing reproductive problems. Since exposures during tree-marking operations have never been quantified, an industrial hygiene survey was conducted at two USFS regions to characterize current exposures to these paints. Seven bulk paint samples were analyzed for volatile organic compounds (VOCs) and elements, and the results were used to select specific compounds for personal exposure assessment based on whether the compounds have had any documented association with reproductive health effects and whether a method for assessment existed. The personal exposure assessment consisted of collecting full-shift personal breathing zone (PBZ) air samples during tree-marking operations and spot urine samples at the end of the shift from 10 workers (5 per region). PBZ samples were analyzed for toluene, xylene, ethyl benzene, propylene glycol monomethyl ether aceta te, n-butyl acetate, methyl isobutyl ketone (MIBK), a total hydrocarbon measurement (based on Stoddard solvent), elements, and total particulate. Urine samples were analyzed for hippuric acid (toluene metabolite), o-cresol (also a toluene metabolite), total methylhippuric acids (xylene metabolites), mandelic acid (ethyl benzene metabolite), methyl ethyl ketone (MEK), and MIBK. The results suggest that paint exposures as a result of marking trees are quite low. Except for low concentrations of Stoddard solvent (1.02 to 6.3 mg/ m3) and xylene (0.07 to 0.12 ppm), inhalation exposures to VOCs were not quantifiable. This is not surprising, since the work is outside. The results are similarly low or not detected for inhalation exposures to elements. The urine sampling results suggest that internal doses received from paint exposure also range from not detected to quite low. In both locations, the hippuric acid concentrations were all well below the 1.5 grams per gram of creatinine (g/g Cr) which is normally found in urine. o-Cresol was not detected in workers from one region, but was detected in workers from the other at concentrations just above the analytical limit of detection and the refer- ence range of <0.1 milligrams per liter (mg/L), which suggests that the internal dose to toluene was low. Also, two workers from one region and three from the other had detectable MEK concentrations in their urine that were all an order of magnitude below the American Conference of Governmental Industrial Hygienists Biological Exposure Index (ACGIH BEITM) of 2 mg/L, but above the reference range of <0.1 mg/L for unexposed populations. Overall, the PBZ and urine samples suggest a very low level of VOC and element exposure from tree-marking operations. These sampling results indicated that the only individual compounds that a tree-marker might have been exposed to in detectable concentrations during these surveys and that have a slight but potential, association to reproductive health effects were MEK, toluene, and manganese. All the measured exposures were well below any current occupational exposure limits, but the relevant occupational exposure limits are not based on reproductive effects. Reproductive systems are quite sensitive, and even very low paint exposure could not be completely dismissed as a possible contributor to reproductive health effects, if any association is documented by the epidemiologic study.
Forestry-workers; Forestry; Epidemiology; Paints; Painting; Reproductive-hazards; Reproductive-effects; Reproduction; Exposure-levels; Industrial-hygiene; Workers; Worker-health; Breathing-zone; Air-samples; Urinalysis; Toluenes; Xylenes; Propylenes; Methyl-compounds; Hydrocarbons; Particulates; Inhalants; Exposure-levels
American Industrial Hygiene Conference and Exposition, May 19-23, 1997, Dallas, Texas