The association of cancer risks with pentachlorophenol exposure: Focusing on community population in the areas along certain section of Yangtze River in China

Pentachlorophenol (PCP) was used in large quantities, and mainly for killing the intermediate host snails of schistosome in China, thereby resulting in ubiquitous PCP residue in the environment. However, studies considering the carcinogenicity of PCP for humans mainly focused on occupational workers, and the actual carcinogenicity of PCP for general population is uncertain. To investigate the association between cancer risks and PCP exposure in a community population, an ecological study was conducted in three contaminated areas along the Yangtze River. Standardized rate ratio (SRR) was calculated to represent the risk of cancer incidence, by using incidence in the low PCP exposure category as the reference group. A total of 15,962 cancer records were collected, and 76 water samples and 213 urine samples in three areas were examined. Our findings suggested that compared with the low PCP group, the high PCP group had significantly excessive incidences of various cancers related to different organs including lymph (SRR = 19.44, 95% CI = 15.00–25.19), blood (SRR = 17.24, 95% CI = 12.92–23.01), nasopharynx (SRR = 3.97, 95% CI = 3.75–4.21), gallbladder (SRR = 3.46, 95% CI = 3.09–3.87), pancreas (SRR = 3.41, 95% CI = 3.07–3.79), respiratory system (SRR = 3.41, 95% CI = 3.27–3.57) and liver (SRR = 3.31, 95% CI = 3.09–3.56). Taken together, our present study provides evidence that general community population exposed to high level of PCP exhibits a broader spectrum of increased cancer risks as compared to occupational groups. - Highlights: • Long-term exposure to pentachlorophenol in source of drinking water may increase malignant cancer risks. • General community population exposed to high level of PCP exhibits a broader spectrum of increased cancer risks. • Local residents pertained to the district with high PCP exposure have high levels of urinary PCP residue. • Cancer incidences in population using source water from Yangtze River were higher than those using other types of source water. - General community population exposed to high level of PCP exhibits a broader spectrum of increased cancer risks.