Association between oil spill clean-up work and thyroid cancer: Nine years of follow-up after the Hebei Spirit oil spill accident.

In 2007, an unprecedented oil spill occurred in Taean, Korea. Although crude oil contains chemicals that could increase thyroid cancer risk, few studies have examined the long-term effects of oil exposure during clean-up and thyroid cancer incidence. We investigated the long-term thyroid cancer incidence among participants involved in clean-up work. 1798 participants engaged in at least two surveys since the baseline was tracked from 2008 to 2018. Participants reported the days they participated in oil clean-up works and cancer diagnoses. Cox proportional hazard models were used to estimate the hazard ratios between clean-up work duration and thyroid cancer. Over the 9-year follow-up, 30 thyroid cancer cases were diagnosed. A positive association was observed between clean-up duration and thyroid cancer risk. This effect was more pronounced among residents living <50 m from traffic roads. Our results indicate that crude oil clean-up work participation may increase the thyroid cancer risk.

Long-term effects of the Hebei Spirit oil spill on the prevalence and incidence of allergic disorders.

The Hebei Spirit oil spill accident occurred in December 2007, approximately 10 km off the coast of Taean, South Korea, a location notably close to residential areas. Crude oil substances have been detected in various environmental mediums since the accident, yet previous studies have primarily focused on the acute effects of oil exposure due to the short latency period of allergic diseases. Therefore, this study evaluated the long-term effects of oil spill exposure on allergic disorders. Our study included adult residents who had participated in the Health Effects Research on Hebei Spirit Oil Spill (HEROS) study up to five years post-incident, which was a prospective cohort to monitor the health status of Taean residents. We used two indicators to assess oil spill exposure, namely the distance from the initial contaminated coastline to each participant's residence and the number of days participants had engaged in oil clean-up work. Current symptoms such as asthma, allergic rhinitis, atopic dermatitis, allergic conjunctivitis, and multimorbidity were considered allergic disorders. In the baseline survey, the prevalence of asthma, allergic rhinitis, atopic dermatitis, allergic conjunctivitis, and allergic multimorbidity symptoms was associated with both exposure indicators; however, these associations were not observed in the two consecutive surveys. Significant longitudinal associations between oil spill exposure indicators and the four allergic disorders, as well as multimorbidity incidences, were observed during a five-year follow-up period. Our results suggest that oil spill exposure can affect acute and long-term allergic symptoms in residents near the accident site.

Evaluating the feasibility of air environment management system for VOCs through 'VOCs specification' of petroleum refining industry.

The chemical industry releases various types of volatile organic compounds (VOCs) into the atmosphere, and the concentration of VOCs emitted from chimneys is regulated worldwide. However, some VOCs such as benzene are highly carcinogenic, while others such as ethylene and propylene may cause secondary air pollution, owing to their high ozone-generating ability. Accordingly, the US EPA(United State, Environment Protect Agency) introduced a fenceline monitoring system that regulates the concentration of VOCs at the boundary of a facility, away from the chimney source. This system was first introduced in the petroleum refining industry, which simultaneously emits benzene, affecting the local community because of its high carcinogenicity, and ethylene, propylene, xylene, and toluene, which have a high photochemical ozone creation potential (POCP). These emissions contribute to air pollution. In Korea, the concentration at the chimney is regulated; however, the concentration at the plant boundary is not considered. In accordance with the EPA regulations, Korea's petroleum refining industries were identified and the limitations of the Clean Air Conservation Act were studied. The average concentration of benzene at the research facility examined in this study was 8.53 µg/m3, which complied with the benzene action level of 9 µg/m3. However, this value was exceeded at some points along the fenceline, in proximity to the benzene-toluene-xylene (BTX) manufacturing process. The composition ratios of toluene and xylene were 27% and 16%, respectively, which were higher than those of ethylene or propylene. These results suggest that reduction measures in the BTX manufacturing process are necessary. This study shows that legal regulations should enforce reduction measures through continuous monitoring at the fenceline of petroleum refineries in Korea.Implications: Although volatile organic compounds(VOCs) are essential in various industrial sites, they adversely affect the health of people in the near community. Benzene is highly carcinogenic, so it is dangerous if exposed continuously. In addition, there are various types of VOCs, which combine with atmospheric ozone to generate smog. Globally, VOCs are managed as Total VOCs. However, through this study, VOCs have priority, and in the case of the petroleum refining industry, it is suggested that VOCs should be preemptively measured and analyzed to be regulated. In addition, it is necessary to minimize the impact on the local community by regulating the concentration at the fenceline beyond the chimney measurement.