Abstract | OBJECTIVE: To determine whether hepatic biochemical changes, as measured by routinely available tests indicative of hepatocellular necrosis, cholestasis, or altered hepatic clearance of bilirubin, occur in association with low to moderate exposure to styrene commonly experienced in industrial production. METHODS: RESULTS: A consistent and significant linear trend for increasing direct bilirubin and direct/total bilirubin ratio was found in association with increasing exposure to styrene, by both air and blood monitoring, in both studies. Mean direct bilirubin concentrations increased from 0.05-0.08 mg% in referents to 0.12-0.19 in workers exposed above 25 ppm, with a significant exposure-response trend (p<0.005). Significantly increased direct/total bilirubin ratios, ranging from 0.22 to 0.35 were associated with exposure to styrene (p<0.001), indicating diminished hepatic clearance of conjugated bilirubin. Also, a significant linear association between the hepatic transaminases ALT and AST and exposure to styrene was found in pooled regression analyses, with an increase in AP of about 10 IU/ml in workers exposed above 25 ppm air or 0.275 mg/l blood styrene in pooled analyses from both studies. CONCLUSIONS: The consistent finding of increased direct bilirubin and AP concentrations in these two independent studies provides evidence for diminished hepatic clearance of conjugated bilirubin with associated cholestasis in workers exposed to styrene. The finding of a significant linear association between hepatic transaminase concentrations and exposure to styrene in pooled analyses is consistent with mild hepatic injury and associated metabolic dysfunction.
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Authors | C A Brodkin, J D Moon, J Camp, D Echeverria, C A Redlich, R A Willson, H Checkoway |
Journal | Occupational and environmental medicine
(Occup Environ Med)
Vol. 58
Issue 2
Pg. 95-102
(Feb 2001)
ISSN: 1351-0711 [Print] England |
PMID | 11160987
(Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- Biomarkers
- Styrene
- gamma-Glutamyltransferase
- Aspartate Aminotransferases
- Alanine Transaminase
- Alkaline Phosphatase
- Bilirubin
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Topics |
- Adult
- Alanine Transaminase
(blood)
- Alkaline Phosphatase
(blood)
- Analysis of Variance
- Aspartate Aminotransferases
(blood)
- Bilirubin
(blood)
- Biomarkers
(blood)
- Chemical and Drug Induced Liver Injury
- Cross-Sectional Studies
- Female
- Humans
- Liver Diseases
(enzymology)
- Male
- Occupational Exposure
(adverse effects)
- Styrene
(adverse effects)
- gamma-Glutamyltransferase
(blood)
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