Levels and distribution of PCDD/Fs, dl-PCBs, and organochlorine pesticides in sediments from the lower reaches of the Haihe River basin, China

Abstract

The concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), dioxin-like polychlorinated biphenyls (dl-PCBs), and organochlorine pesticides (OCPs) in surface sediments from the lower reaches of the Haihe River basin, northern China, were determined by high-resolution gas chromatograph-high-resolution mass spectrometer. The concentrations of 2,3,7,8-substituted PCDD/Fs, dl-PCBs, and total OCPs [sum of hexachlorobenzene, hexachlorocyclohexanes, and dichlorodiphenyltrichloroethane (DDTs)] in 17 sediment samples were in the ranges of 11.6-1,180,924 pg/g dry weight (dw), 18.7-50,017 pg/g dw, and 1.7-35,280 ng/g dw, respectively. The contamination levels in the samples varied significantly between the different sites. Abnormally high concentrations of PCDD/Fs, dl-PCBs, and some OCPs were found in sediments from the lower reaches of the main channel of the Haihe River and the Dagu Drainage River, which were attributed to the historical production of pentachlorophenol and other pesticides near these locations. High levels of DDTs were detected in the Yongding New River sediment, which were likely to have originated from the discharge of wastewater from a dicofol factory upstream. In samples taken from other sites, the concentrations of these pollutants were at levels comparable to those documented in other areas of China. This preliminary investigation suggests that historical pesticide production in the Haihe River basin has contributed significantly to the contamination of this aquatic ecosystem and that further attention to this issue is warranted.

An assessment of the concentrations of PCDDs/Fs in contaminated bottom sediments and their sources and ecological risk

“…However, other experimental results suggest that the concentrations of PCDDs/Fs in sediments are not all dependent on TOC (Ikenaka et al 2005;Lee et al 2006;Pan et al 2010;Nunes et al 2011;Li et al 2012;Eichbaum et al 2016). Li et al (2012) report a poor correlation between PCDDs/Fs and TOC in bottom sediments, indicating that they are influenced by seasonal changes, while Vẚcha et al 2011note a weak correlation between POP concentration and the content and quality of organic matter in sediment. In addition, PCDD/F levels have been found to be as much as 16-fold higher in silt and clay particles than in sand or coarse particles (Lee et al 2006).…”

“…Similar results were reported in the studies of other authors (Lee et al 2006;Waszak and Dąbrowska 2009;Nieuwoudt et al 2009;Chen et al 2013;Nie et al 2013;Lewnadowski et al 2014). The high share of OCDD and HpCDD in the total PCDDs/Fs could be associated with atmospheric input from a variation of combustion process and the historical use of sodium pentachlorophenate as a wood preservative, herbicide, fungicide, bactericide, algaecide, snail cider and insecticide in the study area (Lee et al 2006;Li et al 2012;Nie et al 2013). Urbaniak et al (2013) highlight the role of industrial and domestic effluents, spills and other factors as the main sources of elevated concentrations of PCDDs/Fs in urban reservoir sediments, with a particular emphasis on the effects of atmospheric deposition and further scouring of deposited PCDDs/ Fs during rains (storm water runoff).…”

“…Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/Fs) are both examples of persistent organic pollutants (POPs) (Lee et al 2006;Li et al 2012;Lewandowski et al 2014;Förstner et al 2016;Louchouarn et al 2018). The persistence and hydrophobicity of PCDDs/Fs and their resistance to degradation make them a significant ecotoxicological problem, one that is difficult to control (Nieuwoudt et al 2009;Roumak et al 2018).…”

“…Moreover, due to their high octanol-water partition confections (log K ow 4-8), PCDDs/Fs undergo bioaccumulation in sediment-dwelling organisms and biomagnification in both aquatic and terrestrial food chains (Lee et al 2006;Micheletti et al 2007;Nunes et al 2011;Nie et al 2013;Urbaniak et al 2014;Förstner et al 2016;Roumak et al 2018). Consequently, the determination of PCDD/F concentrations in bottom sediments plays an important part in determining their ecological risk and human exposure (Micheletti et al 2007;Li et al 2012). The precise qualitative and quantitative composition of organic matter, including humus substances, soluble organic matter and black carbon fractions, is believed to be a key element in determining potential PCDD/F accumulation in bottom sediments (Perminova et al 2006(Perminova et al , 2019Ghosh 2007).…”

Spatial distribution and seasonal variation of four current-use pesticides (CUPs) in air and surface water of the Bohai Sea, China

“…The target compounds are expected to discharge into the Bohai Sea through the runoff of the Yellow and Haihe Rivers (Fig. 1), which are among the seven largest water systems in China, and receive large volumes of industrial or agricultural wastewater leading to serious pollution levels (Li et al, 2013;Li et al, 2016). For example, the Yellow River flows through Zibo City, which is the largest production base of Chlorpyrifos in Northern China (15,000 t/y), this may explain the high concentration of Chlorpyrifos in SW6 and SW7.…”