Occurrence, homologue patterns and source apportionment of short- and medium-chain chlorinated paraffins in suburban soils of Shanghai, China

Chlorinated paraffin (CP) production is one important emission source for short- and medium-chain CPs (SCCPs and MCCPs) in the environment. In this study, 48 CP congener groups were measured in the surface soils and coniferous leaves collected from the inner and surrounding environment of a CP production plant that has been in operation for more than 30 years to investigate the dispersion and deposition behavior of SCCPs and MCCPs. The average concentrations of the sum of SCCPs and MCCPs in the in-plant coniferous leaves and surface soils were 4548.7 ng g dry weight (dw) and 3481.8 ng g dw, which were 2-fold and 10-fold higher than those in the surrounding environment, respectively. The Gaussian air pollution model explained the spatial distribution of CPs in the coniferous leaves, whereas the dispersion of CPs to the surrounding surface soils fits the Boltzmann equation well. Significant fractionation effect was observed for the atmospheric dispersion of CPs from the production plant. CP congener groups with higher octanol-air partitioning coefficients (K) were more predominant in the in-plant environment, whereas the ones with lower K values had the elevated proportion in the surrounding environment. A radius of approximately 4 km from the CP production plant was influenced by the atmospheric dispersion and deposition of CPs.

Section: ■ Results and Discussionmentioning

confidence: 77%

Dispersion of Short- and Medium-Chain Chlorinated Paraffins (CPs) from a CP Production Plant to the Surrounding Surface Soils and Coniferous Leaves

Gao

Zhang

et al. 2016

“…1−3 Current research on CPs mainly focuses on SCCPs which show characteristics of persistence, long-range transport, bioaccumulation, and toxicity. 2,4−7 Studies have shown that SCCPs could be detected in various environmental and human samples, including air, 8,9 dust, 10,11 soil, 12,13 sluge, 14,15 biota, 16−18 human blood, 19 breast milk, and maternal and cord serum. 20,21 Since SCCPs have been listed in Annex A of the Stockholm Convention in 2017, 22 the production and usage of MCCPs as replacement chemicals is increasing.…”

Section: Introductionmentioning

confidence: 99%

“…Chlorinated paraffins (CPs) include a range of chlorinated n -alkanes divided into short-, medium-, and long chain chlorinated paraffins (SCCPs (C 10 -C 13 ), MCCPs (C 14 -C 17 ), and LCCPs (C ≥18 )) based on the carbon chain length. CP products, such as CP-42 and CP-52, are widely used as secondary plasticizers in rubber/paints/plastics/sealants, flame retardants, and metal cutting fluids, resulting in a great amount of CPs released into the environment and entering food webs. − Current research on CPs mainly focuses on SCCPs which show characteristics of persistence, long-range transport, bioaccumulation, and toxicity. ,− Studies have shown that SCCPs could be detected in various environmental and human samples, including air, , dust, , soil, , sluge, , biota, − human blood, breast milk, and maternal and cord serum. , Since SCCPs have been listed in Annex A of the Stockholm Convention in 2017, the production and usage of MCCPs as replacement chemicals is increasing. The total registered volume of MCCPs production in Europe was about 10000–100000 t/year, much higher than that of SCCPs (1000–10000 t/year) .…”

Section: Introductionmentioning

confidence: 99%

Medium- and Short-Chain Chlorinated Paraffins in Mature Maize Plants and Corresponding Agricultural Soils

Chen

Hou

Liu

et al. 2021

For the most complex artificial chlorinated environmental contaminants, much less is known for medium-chain CPs than short-chain CPs. In this research, the spatial distributions of MCCPs and SCCPs in farmland soil and maize leaves near a CP production facility were found marginally influenced by seasonal winds. The levels of ∑MCCPs and ∑SCCPs were in the ranges of <1.51−188 and 5.41−381 ng/g dw for soils; and 77.6−52930 and 119−61999 ng/g dw for maize leaf, respectively. Bioaccumulation and tissue distributions of the CPs within maize plants were specifically analyzed. Most of the CPs were contained in the tissues directly exposed to airborne CPs. Though the estimated risk of CPs to humans through ingestion of kernels appears to be minimal, the edible safety of MCCPs in maize plants for cattle was nearly in the designated range of adverse effects. To our knowledge, this is the first report on bioaccumulation of CPs in mature maize plants, especially in the parts eaten by humans and domestic animals. It provides a baseline reference to the edible risks of CPs in agricultural food plants and alerts us to the problematic environmental behavior of MCCPs, a probable future replacement for SCCPs commercially.

“…4 However, some studies indicate that MCCPs and LCCPs are more problematic than SCCPs due to longer carbon chains and higher chlorine content, which might slow down biodegradation and increase susceptibility to bioaccumulation. 6,7 CPs are widespread among almost all environmental matrices, including air, 8,9 water, 10,11 soil, 12 sediment, 13 and wildlife, 14,15 but also in other matrices such as sewage sludge, 16 e-waste, 17 household dust, 18−20 and human breast milk. 21 The quantification of individual CP congeners in complex CP technical products presents a great analytical challenge.…”

Section: ■ Introductionmentioning

confidence: 99%

Partitioning of Chlorinated Paraffins (CPs) to Daphnia magna Overlaps between Restricted and in-Use Categories

Castro

Breitholtz

Yuan

et al. 2018

Chlorinated paraffins (CPs) are high-production volume industrial chemicals consisting of n-alkanes (with 10 to 30 carbon atoms in the chain) with chlorine content from 30 to 70% of weight. In Europe, the use of short chain chlorinated paraffins (SCCPs) has been restricted by the Stockholm Convention on POPs due to their PBT (persistent, bioaccumulative and toxic) properties. Medium (MCCPs) and long chain (LCCPs) chlorinated paraffins are used as substitution products. In this work we studied the partitioning behavior of five different CP technical mixtures from the established categories (2 SCCPs, 1 MCCP, 1 LCCP and 1 CP technical mixture covering all categories) using passive dosing, by determining the partitioning coefficient of CP technical mixtures between silicone and water ( K) as well as between organic matter and water ( K). We show that both silicone-water and organic carbon-water partition coefficients overlap between different categories of CP technical mixtures. These results indicate that in-use MCCPs and LCCPs may be equally or more bioaccumulative than restricted SCCPs. For the tested mixtures, both chlorine content and carbon chain length showed a significant correlation with both K and K.