In this study, a residential cohort was used to investigate whether cancer incidence was increased for people who had lived in the vicinity of a petrochemical complex for 12 years since the establishment. The study was conducted by a research team led by Dean Chang-Chuan Chan from the National Taiwan University College of Public Health and was published in International Journal of Hygiene and Environmental Health in March.
A cohort of 2,388 long-term residents aged above 35 years in 2009-2012 who lived within a 40 km radius of No. 6 Naphtha Cracking Complex, the largest petrochemical complex in Taiwan, was recruited.Researchers measured their internal exposure biomarkers of urinary carcinogenic metals and retrospectively compared cancer incidences between those who lived in high exposure (HE) and low exposure (LE) areas for 12 years, since the complex began operating in mid-1999. Crude cumulative incident rates (CIRs) of all cancers were calculated for new cancer cases recorded in Taiwan Health Insurance Database. Poisson regression was applied to estimate relative risks for the CIRs of all cancers between HE and LE areas during the 10-12 years since the beginning of the complex’s operation after adjusting for confounders.
All cancers were increased for residents, especially for females and elders, living within 10 km of the petrochemical complex 9 years after the complex began operating. And, this occurred via elevated pollution from a mixture of carcinogenic air pollutants emitted from power plants, oil refineries and petrochemical manufacturing plants.
The study overcome some limitations, such as the lack of individual exposure information and key risk factors in ecological studies, the absence of latent periods for cancer cases in case-control studies, and the absence of clear-cut time periods with which to classify petrochemical manufacturing operations. The implication of this study provides a good mirror when researchers try to deal with the environmental epidemiological study for a huge and complicated stationary air pollution source.
Int J Hyg Environ Health. 2018 Mar;221(2):308-314. doi: 10.1016/j.ijheh.2017.12.004. Epub 2017 Dec 14. Increased cancers among residents living in the neighborhood of a petrochemical complex: A 12-year retrospective cohort study. Yuan TH, Shen YC, Shie RH, Hung SH, Chen CF, Chan CC.