OBJECTIVETo explore the effect of polycyclic aromatic hydrocarbons on the neurobehavioral function of coke oven workers.

METHODS200 healthy adult male coke oven workers were selected from a coke plant of a state-owned steel enterprise in Taiyuan City. 88 controls occupationally unexposed to polycyclic aromatic hydrocarbons (PAHs) were selected from the same enterprise. All the subjects participated in this investigation voluntarily in their consent. Concentration of B(a)P in the working environment was monitored by High Performance Liquid Chromatography (HPLC). Urine samples were sampled immediately after working shifts. The level of urinary 1-hydroxypyrene was determined by HPLC. General information of workers correlated with the investigation was collected in a questionnaire according to the same criteria by well-trained investigators. Neurobehavioral core test battery (NCTB) recommended WHO was performed on coke oven workers and controls to test the neurobehavioral changes and the mood state.

RESULTSthe concentration of B(a)P at oven bottom,oven side and oven top were 0.0195 microg/m3, 0.186 microg/m3 and 1.624 microg/m3 respectively, that at oven side and oven top being higher than the one stipulated by the occupational hygiene criterion. Urinary 1-hydroxypyrene was significantly different between the exposure group (3.42 +/- 0.98 micromol/mol creatinine) and control group (2.75 +/- 1.09 micromol/mol creatinine). No significant differences were found between exposure group and control group of age, working years, smoking, drinking and unhealthy food consumption; however, compared to the controls, the scores of total digital span, the forward digital span, and right dotting in the coke oven workers were lower, but that of total dotting was higher, with a statistical significance. According to urinary 1-hydroxypyrene concentration, all the subjects were divided into three groups. (<3.10 micromol/mol creatinine, 3.10 micromol/mol creatinine, >3.87 micromol/mol creatinine). Significant differences of the total digital span, the forward digital span, backward digital span, digit symbol and Benton visual retentions existed in different urinary 1-hydroxypyrene concentration groups and showed a dose-response tendency. Results of multiple stepwise regression analysis and correlation analysis showed that the level of urinary 1-hydroxypyrene affected memory and perception of coke oven workers and negative correlations between the level of urinary 1-hydroxypyrene and changes in neurobehavioral function were found.

CONCLUSIONPAHs mainly causes decrease of memory and perception in coke oven workers.