An Analysis of the Exposure Level of Polycyclic Aromatic Hydrocarbons in Downwind Residents of a Coking Plant and its Influencing Factors

Objective To investigate the exposure level of polycyclic aromatic hydrocarbons (PAHs) in downwind residents of a coking plant and its influencing factors using the hydroxy metabolites (2-hydroxy naphthalene, 9-hydoxy fluorene, 1-hydroxy phenanthrene, 1-hydroxy pyrene, and 3-hydroxy benzoapyrene) of PAHs in the urine as biomarkers.

Methods A health questionnaire was used to collect the health information of the non-occupational population who were long-term residents in the downwind areas of the polluting enterprise; meanwhile, their urine samples were collected for determination of hydroxy metabolites of PAHs using high-performance liquid chromatography. A Spearman correlation analysis was performed between the test results of the above 5 metabolites and variables such as population gender, age, body mass index, daily smoking quantity, mean drinking frequency, frequency of having barbecues, and duration of outdoor activities. A multiple linear regression analysis was performed taking the test results of the above five metabolites as dependent variables and the above seven variables as independent variables.

Results The Spearman correlation analysis showed that 2-hydroxy naphthalene was positively correlated with daily smoking quantity and frequency of having barbecues (P < 0.01); 1-hydroxy phenanthrene and 1-hydroxy pyrene were positively correlated with age, daily smoking quantity, and duration of outdoor activities (P < 0.01); 3-hydroxy benzoapyrene was positively correlated with duration of outdoor activities (P < 0.01). The multiple linear regression analysis showed that an increased daily smoking quantity was associated with higher urine levels of 2-hydroxy naphthalene, 9-hydoxy fluorene, 1-hydroxy pyrene, and 3-hydroxy benzoapyrene (P < 0.05); an increased frequency of having barbecues per month was associated with higher urine levels of 1-hydroxy pyrene and 3-hydroxy benzoapyrene (P < 0.05); an increased duration of outdoor activities was associated with higher urine levels of 1-hydroxy phenanthrene and 1-hydroxy pyrene (P < 0.05).

Conclusion Smoking quantity, frequency of having barbecues, and duration of outdoor activities are influencing factors for exposure to PAHs in this population.