Identification and evaluation of chlorinated nonane paraffins in the environment: A persistent organic pollutant candidate for the Stockholm Convention?
Short-chain chlorinated paraffins (SCCPs), with 10–13 carbon atoms, are persistent organic pollutants under the Stockholm Convention because they are persistent, toxic, and bioaccumulative. However, little information is available on CPs with <10 carbon atoms. C9-CPs were identified and quantified in environmental matrices in this study. The occurrences and sources of C9-CPs in environmental samples were investigated by determining C9-CPs in technical CP products and environmental matrices, including indoor air and sediment, by GC×GC‒ECNI‒TOFMS. Quantitative structure-property relationship modeling revealed C9-CPs have high octanol-water partition coefficients (log Kow 5.99), octanol-air partition coefficients (log Koa 7.24), and bioaccumulation factors (log BAF 4.07), indicating C9-CPs are semivolatile and could bioaccumulate. C9-CPs were detected in different fish (at 3.4–153 ng/g dw), confirming they can bioaccumulate. C9-CPs were found in soil (at 3.0–25.6 ng/g dw) and biota (at 7.5–57.8 ng/g dw) from the Antarctic, demonstrating they can undergo long-range transport and are global pollutants. This is the first comprehensive study reporting the sources, occurrences, and fates of C9-CPs in the environment, laying foundations for further evaluation of C9-CPs and their inclusion as candidate persistent organic pollutants under the Stockholm Convention.