The Yunlin County Government has contracted National Taiwan University (NTU) to conduct a cohort study on air pollution and health among residents near the No. 6 Naphtha Cracker Complex, which is located in Miliao Township, Yunlin County, Taiwan since 2009. This is the fourth year of this series of four-year study. The study areas are 10 townships surrounding the petrochemical complex, including Baojhong, Taisi, Sihhu, Dongshih, Mailiao, Lunbei, Erlun, Citong, Yuanchang and Huwei. These townships are classified as three zones based on their distance to the petrochemical complex. Zone A includes Mailiao and Taisi which are within 10km radius of the petrochemical complex; Zone B includes Baojhong, Sihhu, Dongshih and Lunbei, townships which are located 10-20km radius of the petrochemical complex; and Zone C includes Erlun, Citong, Yuanchang and Huwei townships which are located within 20-30km radius from the petrochemical complex. The NTU research team adopted a multiple-disciplinary approach to conduct this study, including environmental monitoring and epidemiological cohort study. For environmental monitoring, we used the pollution roses to analysis the data of Taisi air monitoring station for investigating how SO2 pollution varies between different wind speeds, times of day, and periods of No. 6 Naphtha Cracker Complex development in Zone A. We used the data of Taisi photochemical monitoring station and photochemical monitoring mobiles to understand the No. 6 Naphtha Cracker Complex’ exposure impact of volatile organic compounds (VOCs) in Zone A. We conducted PM10 samples for heavy metals, PM2.5 samples for polyaromatic hydrocarbons (PAHs) by Harvard impactor, and SO2, NO, NO2, and NOx samples by Ogawa passive sampler from 40 locations in Zone A in two seasons. For the established epidemiological cohort with a total of 3,230 residents, we analyzed their health insurance data and detected their HBsAg and Anti-HVC. We analyzed the relationship between air pollutants levels and exposure dose for the epidemiological cohort, and completed biological monitoring of 2,781 residents’ urinary 1-hydroxypyren (1–OHP) and 2,394 resident’s urinary heavy metals, and conducted the metabolomics analysis for high and low exposure groups in the epidemiological cohort. We recruited a susceptible cohort of 147 new subjects, including 90 pregnant women and 57 new-born babies, and followed up 68 1-year babies and 33 2-years babies. The main findings of environmental monitoring are: (1) The results of SO2 monitoring in Zone A showed that the SO2 levels in sampling sites less than 3 km from No. 6 Naphtha Cracking Complex were higher than those in farther sampling sites. The operation of No. 6 Naphtha Cracking Complex has influenced the SO2 pollution in Zone A. The EPA has regulated a new 1-hr SO2 standard of 75 ppb, and the downwind areas of the No. 6 Naphtha Cracking Complex have been exceeding this level since operations at the complex began. (2) The No. 6 Naphtha Cracking Complex impacted on the concentrations of ethylene, polypropylene, propane, butane, and benzene in Zone A. The contribution of benzene pollution from No. 6 Naphtha Cracking Complex in Zone A is higher than that of local traffic, and the high concentration of benzene is usually caught on day time with high wind speed. (3) The results of metals and PAHs monitoring in Zone A showed that the Ant, Chry, Fl, Phe, and Pyr of PAHs and the As, Ba, Co, Cr, Li, Mn, Rb, and Sr of metals levels in sampling sites less than 5 km from No. 6 Naphtha Cracking Complex were higher than those of 90 percentile levels in whole year. The main findings of epidemiological cohort are: (1) The crude incidence rate of all cancer of residents in Zone A during 2008-2010 was 4.07 times of that during 1999-2001, and it was higher than that of residents in Zone B and Zone C during 2008-2010. (2) The significant different intensity on the metabolites of lipoprotein, lipid, amino acid, intermediate compound in the metabolism of carbohydrates, and glycoprotein were found between the residents of high exposure group with high levels of urinary V and 1-OHP and the residents of matched low exposure group. (3) After adjusting for confounding factors, multiple regression analysis showed that residents’ urinary V levels were elevated by 0.38 μg/g-creatinine with a 1 ng/m3 increase in ambient V concentrations at their addresses, and residents’ log-transformed urinary 1-OHP levels (μg/g-creatinine) were significantly elevated by 0.39 with the increase of 1 log-transformed ambient pyrene concentrations (ng/m3) at their addresses. Our main findings of this year conclude that the air pollution, exposure and health effect all show a distance-to-source trend surrounding the No. 6 Naphtha Cracking Complex.

Petrochemical Industry;Epidemiology;Air Pollution