ABSTRACT
OBJECTIVE: To explore the dose-response relationship between exposure to polycyclic aromatic hydrocarbons (PAHs) and the elevation of some serum liver enzymes in coke oven workers. METHODS: Cumulative exposure level of total 16 PAHs (CEL-PAHs) and urinary 1-hydroxypyrene (1-OHP) concentrations were assessed, liver enzymes including alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT) and alkaline phosphatase (ALP) were determined between coke oven workers and non-occupational PAHs exposed workers with negative hepatitis B surface antigens (HBsAg). RESULTS: The exposure levels of PAHs in coke oven workers were significantly higher than in control group (P < 0.05). Compared with referents, significant elevation of serum ALT can be found in the group of CEL-PAHs minor than 50 microg/(m3 x a) or in the group of urinary 1-OHP concentrations minor than 2.3 micromol/mol creatinine, as well as significant elevation of serum AST in the group of CEL-PAHs minor than 50 microg/(m3 x a) (P < 0.05). Compared with control group, the elevation of enzyme level in all four serum liver and the higher prevalence of abnormal serum ALT, AST and GGT level can be found both in the group of CEL-PAHs higher than 200 microg/(m3 x a) and in the group of urinary 1-OHP concentrations higher than 10.0 micromol/mol creatinine (P < 0.05), especially for the elevation of enzyme level in serum GGT (10-fold increase in CEL-PAHs resulted in 1.24-fold increase in serum GGT, as well as 10-fold increase in urinary 1-OHP resulted in 1.19-fold increase) and higher prevalence in serum GGT (logistic analysis: adjusted Odds Ratio: 6.2 - 7.2, P < 0.05). CONCLUSION: The elevation of some liver enzymes in coke oven workers may be related to their high exposure level of PAHs.