Short- and medium-chain chlorinated paraffins in sediments from the Laizhou Bay area, North China: Implications for transportation from rivers to marine environment

Abstract

The concentrations of short-and medium-chain chlorinated paraffins (SCCPs and MCCPs) were measured for riverine and marine sediments from the Laizhou Bay area in order to investigate their spatial distributions, possible sources and transport behaviors. Concentrations of SCCPs and MCCPs in riverine sediments varied from 8.4 to 2000 ng g À1 dw and from 1.8 to 3200 ng g À1 dw, respectively. Higher concentrations were found exclusively at industrial sites. Emissions from local factories were the main source of CPs in river sediments of this region. It was 5e22 ng g-1 dw and 6e63 ng g À1 dw with an average value of 11 ng g À1 dw and 9 ng g À1 dw for SCCPs and MCCPs in marine sediments of Laizhou Bay, respectively. In addition to riverine input, ship related emissions are suggested to be another important source of CPs in the Laizhou Bay. MCCPs/SCCPs values and compositional profiles of SCCPs were found to vary along with CP concentrations. A distinct shift to congener groups with shorter carbon chains and lower chlorination from emission sources to remote areas was noticed. The role of log octanol-water partition coefficient (LogK ow ) values indicated decisive in their transportation from emission sources to remote areas in the Laizhou Bay area.

Status of short-chain chlorinated paraffins in matrices and research gap priorities in Africa: a review

“…In the aquatic environment, SCCPs are more likely to be adsorbed in sediment since they have low water solubility and high carbon partition coefficients (Environment Canada 2008). There are quite a number of studies that have been reported globally (Wang et al 2019a;Pan et al 2018;Pan et al 2020;Huang et al 2019a;Wang et al 2020a;Labadie et al 2019).…”

“…Thus, Shanghai aquatic system is mainly contaminated by MCCPs than SCCPs. Another study by Pan et al (2018) determined SCCP concentration in sediments from industrial, urban and rural areas of the Laizhou Bay, North China, from 14 September 17 to October 2009. SCCP concentration ranged from 8.4 to 2000 ng g −1 with ∑SCCP concentration of 160 ng g −1 dw.…”

Distributions, transports and fates of short- and medium-chain chlorinated paraffins in a typical river-estuary system

“…All the samples were corrected by blanks, but not by surrogate recoveries. Detailed information about the analytical method is described in the supplementary information and in our latest study (Pan et al, 2018).…”

“…CPs are commonly used as additives in the rubber industry, such as in marine coatings, rubber tires, and polyurethane materials (Tong et al, 2003;Wei et al, 2016). Many researchers have reported that compared to SCCPs, MCCPs are more prone to be adsorbed onto particles and settle in sediment instead of being transported by water over long distance (Chen et al, 2011;Ma et al, 2014;Pan et al, 2018;Zeng et al, 2013a). Thus, the mooring fishing boats might be a major contributor to MCCPs in the Xiaoqing River.…”

“…Among all the rivers flowing into Laizhou Bay, the artificial Xiaoqing River is a large contributor to pollution fluxes and runoff (Pan et al, 2011;Pan et al, 2018;Zhong et al, 2011). It originates from Jinan City and flows downstream through the heavily urbanized and industrialized cities of Zibo, Weifang, Binzhou, Dongying, and finally discharges into Laizhou Bay.…”