Health survey of former workers in a Norwegian coke plant: Part. 1. Estimation of historical exposures.
OBJECTIVE
To estimate historical exposure levels at a coke plant for all agents considered to be of importance for epidemiological studies of mortality and cancer incidence.


METHODS
Time weighted average exposure (8 h TWA) was estimated based on personal measurements for polycyclic aromatic hydrocarbons (PAHs) and carbonaceous particulates. Exposure to quartz was estimated relative to the concentration of carbonaceous particulates. These estimates were adjusted for the use of airstream helmets. Exposure to other agents were estimated qualitatively (asbestos, benzene, and arsenic) or semi-quantitatively (carbon monoxide (CO) and heat) based on measurements and other indicators of exposure.


RESULTS
Exposure to PAHs was highest for those who worked at the top of the ovens (300 micrograms/m3) in the period from 1970-6. The estimated PAH exposure was reduced to an average of 65 micrograms/m3 after the introduction of exposure control measures in 1976. The estimates for carbonaceous particulates ranged from 1 to 16 mg/m3, with the highest exposure for workers at the top of the ovens and at the coke screening station.


CONCLUSIONS
The exposure of greatest concern in this study is to PAHs, but exposures to carbonaceous particulates and CO may also be of importance. The major limitations of this study are the lack of personal measurements before 1975 and the total lack of measurements for some of the exposed categories of workers. Despite these limitations, we think that this assessment reflects the actual exposures for most of the former employees. The assessment thus provides a reasonable tool for the subsequent epidemiological study and for future epidemiological follow up studies at the coke plant.
Romundstad
P R
PR
Department of Occupational Medicine, University Hospital of Trondheim, Norway.
Rønneberg
A
A
Leira
H L
HL
Bye
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D001151:Arsenic; D001194:Asbestos; D001554:Benzene; D002248:Carbon Monoxide; D003077:Coke; D006306:Health Surveys; D006358:Hot Temperature; D006801:Humans; D006841:Hydrocarbons, Aromatic; D008297:Male; D009664:Norway; D016273:Occupational Exposure; D011791:Quartz
D003077:Coke; D006841:Hydrocarbons, Aromatic; D001194:Asbestos; D011791:Quartz; D002248:Carbon Monoxide; D001554:Benzene; D001151:Arsenic