Historical Long-term Exposure to Pentachlorophenol CausingRisk of Cancer - A Community Study

Background: Pervious studies suggested occupational workers exposure to pentachlorophenol (PCP) mightcontribute to increased risk of cancer. However, few studies have focused on associations between PCP and cancerrisk at the community level.
Objective: The present study was to explore the cancer risk for the communitypopulation living long-term in a PCP contaminated area.
Methods: All the cancer cases diagnosed in 2009-2011 in Tongling City were collected. The cancer patients’ residencies were geo-referenced in each district. Thehistorical PCP usage for each district of Tongling was calculated as the PCP pollution index, which was furtherused to divide into PCP exposure categories. Standardized rate ratios (SRRs) of cancer incidence were applied todetect the cancer risk as exposure grade elevated. Correlation analysis was performed to analyze the relationshipbetween PCP pollution and cancer incidence.
Results: A total of 5,288 cancer cases (3,451 male and 1,837 female)were identified. PCP usage was correlated with the incidence of leukemia (r=0.88, P=0.002) for males, and withcancer of the esophagus for males (r=0.83, P=0.008) and females (r=0.71, P=0.020). Compared with the lowexposure category, significant SRRs for total cancer sites was obtained for high PCP exposure category (SRR=1.61,95%CI=1.59-1.62). Most SRR values of the cancer sites were significantly increased as exposure grade elevatedand exposure time extended.
Conclusion: The present study found that community residents living in the PCPcontaminated area had increased risk of cancers. Leukemias, lymphomas and nasopharyngeal and esophagealcancers are most possibly associated with PCP exposure.