Elimination of short-chain chlorinated paraffins in diet after Chinese traditional cooking-a cooking case study.

Short-chain chlorinated paraffins (SCCPs) were listed in the Stockholm Convention in 2017 yet are still used in large-tonnage in China. Diet is the main external exposure pathway of many persistent organic pollutants (POPs), but SCCP diet exposure has not been studied completely thus far. In this study, samples of 122 raw foods were collected from markets in Beijing, cooked with Chinese traditional cooking methods, and analyzed for SCCPs. Overall, SCCP levels in the raw food materials ranged from0.67 to 5100 ng g-1 wet weight (ww). SCCP elimination was found in six out of seven kinds in the cooking case study. Concentrations in the raw food used for cooking ranged from 3.6 to 52 ng g-1 ww, while the corresponding values in the cooked food ranged from 0.67 to 10.8 ng g-1 ww. The SCCP elimination rate ranged from 12% to 93%. The daily average intake of SCCPs for the general population through raw food and cooked food was assessed. The total daily SCCP intake via these foods was 403 and 145 ng kg-1 bw d-1, which suggests that different assessing approaches may result in different estimated SCCP diet exposure amounts.