Occurrence, spatial distribution, and risk assessment of short- and medium-chain chlorinated paraffins in sediment from black-odorous rivers across China

Contamination status, source analysis and exposure assessments of quinolone antibiotics in the south of Yancheng Coastal Wetland, China

Yancheng coastal wetland, the largest coastal wetland in the west coast of the Pacific Ocean and the margin of the Asian continent, has significant environmental, economic and social effects on local human beings. The extensive contamination and potential risk of quinolone antibiotics (QNs) on local aquaculture and human health are still not clear until now. In this study, 52 surface sediment samples were collected to investigate the contamination status and polluted sources, and evaluate ecological risks of QNs in the south of Yancheng coastal wetland. The total contents of QNs ranged from 0.33 to 21.60 ng/g dw (mean value of 4.51 ng/g dw), following the detection frequencies of QNs ranging from 19.23 to 94.23%. The highest content of QNs occurred around an aquaculture pond dominated by flumequine. The total organic carbon contents of sediment were positively correlated with sarafloxacin and lomefloxacin (p < 0.05), indicating the enhanced absorption of these QNs onto sediments. Partial QNs, such as lomefloxacin, enrofloxacin, sarafloxacin and flumequine, presented the homology features originating from the emission of medical treatment and aquaculture. There was no potential risk of QNs to human beings but a potential risk to aquatic organisms (algae > plant > invertebrate). Totally, the management and protection of Yancheng coastal wetland should be of concern with aquaculture as the important industry.

Human dermal exposure to short- and medium-chain chlorinated paraffins: Effect of populations, activities, gender, and haze pollution

Human dermal exposure to chlorinated paraffins (CPs) has not been well documented. Therefore, hand wipes were collected from four occupational populations to analyze short-chain CPs (SCCPs) and medium-chain CPs (MCCPs) in order to estimate dermal uptake and oral ingestion via hand-to-mouth contact. The total CP levels (∑SCCPs and ∑MCCPs) in wipes ranged from 71.4 to 2310 µg/m2 in security guards, 37.6 to 333 µg/m2 in taxi drivers, 20.8 to 559 µg/m2 in office workers, and 20.9 to 932 µg/m2 in undergraduates, respectively. Security guards exhibited the highest levels of ∑SCCPs among four populations (p < 0.01). In undergraduates engaged in outdoor activities, C13 emerged as the most dominant SCCPs homologue group, followed by C12, C11, and C10. The levels of ∑SCCPs and ∑MCCPs in males in light haze pollution were significantly higher than that in heavy haze pollution (p < 0.05). The median estimated dermal absorption dose of SCCPs and MCCPs via hand was 22.2 and 104 ng (kg of bw)-1 day-1, respectively, approximately 1.5 times the oral ingestion [12.3 and 74.4 ng (kg of bw)-1 day-1], suggesting that hand contact is a significant exposure source to humans.

Spatial distribution and ecological risk assessment of short and medium chain chlorinated paraffins in water and sediments of river Ravi, Pakistan

Short (SCCPs) and medium (MCCPs) chain chlorinated paraffins being the emerging organic pollutants have raised serious concerns due to their widespread use and related human health risks. However, their occurrence in aquatic bodies like rivers and associated damage to ecological integrity is yet unknown in some regions of the world. The current study is the first ever assessment of SCCPs and MCCPs in sediment and water of river Ravi, Pakistan. Spatial occurrence and associated ecological risks were investigated from sediments (n = 16) and composite water samples (n = 8) collected at eight locations along the stretch of river Ravi. The concentrations of SCCPs and MCCPs varied from below limit of detection ( Collapse

Key Words

• Aquatic body
• Partitioning coefficient
• Risk assessment
• Source identification
• Total organic carbon

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MESH Headings

• Humans
• Animals
• Chlorine
• Hydrocarbons, Chlorinated/analysis
• Paraffin/analysis
• Rivers
• Pakistan
• Environmental Monitoring
• Risk Assessment
• Carbon
• China

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Grants Collapse

Affiliation(s)

Areej Tahir College of Earth and Environmental Sciences, University of the Punjab, Lahore 54590, Pakistan
Naeem Akhtar Abbasi College of Earth and Environmental Sciences, University of the Punjab, Lahore 54590, Pakistan.
Chang He Queensland Alliance for Environmental Health Science, The University of Queensland, Brisbane 4102, Australia; Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, PR China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
Sajid Rashid Ahmad College of Earth and Environmental Sciences, University of the Punjab, Lahore 54590, Pakistan
Mujtaba Baqar Sustainable Development Study Centre, Government College University, Lahore 54000, Pakistan
Abdul Qadir College of Earth and Environmental Sciences, University of the Punjab, Lahore 54590, Pakistan

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Occurrence, composition, and spatial distribution of dechlorane plus in surface sediments of black-odorous urban rivers across China

China, one of the two dechlorane plus (DP) producers, might have become a major area of DP pollution. The environmental contamination status of DP in sediments across the whole of China has not yet been studied. In the current study, the pollution levels, spatial distribution, and compositions of DP were investigated comprehensively in surface sediments from 173 black-odorous urban rivers across China for the first time. Total DP concentrations varied from not-detected to 39.71 ng/g dw, with an average concentration of 3.20 ± 4.74 ng/g dw, which was polluted by local emission sources and presented significant differences among different sampling cities. Among the seven administrative regions of China, DP concentrations were the highest in South China and showed a decreasing trend from southeastern coastal areas to northwest inland regions. Spearman's correlation analysis suggested that the gross industrial output, gross domestic product, and daily wastewater treatment capacity were not the principal factors controlling the spatial distribution of DP. The fanti values (the concentration ratios of anti-DP to the sum of anti-DP and syn-DP) varied from 0.19 to 0.88, with those in most sediments falling in the range of DP technical product (0.60 ~ 0.80), suggesting no apparent stereoselective enrichment occurred. Moreover, the anti-Cl11-DP was detected in sediments (n.d. ~ 0.40 ng/g dw), which showed significantly and insignificantly positive correlation with the anti-DP levels and fanti, respectively, implying it might mainly originate from the byproduct of DP technical product rather than the dechlorination of anti-DP.

Identification and oxidation of chlorinated paraffins containing nitrate esters, aliphatic sulfates, and thioether amino acids in sewage sludges

Owing to the extensive production and widespread use of chlorinated paraffins (CPs), various CP structural analogs (CPSAs) have been detected in the environment, and these hydrophobic pollutants preferentially adsorb onto sludge during treatment. However, the species and sources of CPSAs in sludge and their subsequent fate during sludge oxidation treatments remain unclear. In this study, 320 nitrogen- or sulfur-containing CPs (205 CPs-N and 115 CPs-S) were detected in sludge through an analysis of Ph4PCl-enhanced ionization coupled with ultra-performance liquid chromatography (UPLC)-orbitrap-mass spectrometry (MS). The intensities of the newly found CPSAs were approximately 3.9-4.1 times those of CPs. Among these CPSAs, 273 previously unknown compounds, namely, 184 CPs-NO3, 63 CPs-SO4H, and 26 CPs-SH, were identified based on the characteristic fragments of NO3, SO4H, and SH, respectively. MS/MS analysis showed that the identified CPs-NO3 included 74 CPs-NO3, 71 CPs-NO3-NH2, 23 CPs-NO3-OH, and 16 CPs-NO3-NH2-OH; CPs-SO4H included 40 CPs-SO4H and 23 CPs-SO4H-OH; and CPs-SH could be divided into 19 2-(methylthio)acetamide-, 6 2-(methylthio)acetamide-cysteine-, and 1 N-acetylcysteine- containing CPs. High abundances of CPs-NO3 and CPs-SO4H were found in both sludge and CP commercial mixtures, indicating that these CPSAs likely originated from the production or use of industrial products. CPs-SH, which were present only in the sludge, were potentially derived from the biotransformation of CPs with amino acids. The oxidation of sludge resulted in the removal of 20.4-60.7 % of the newly identified CPSAs. The oxidation of CPs-NO3 and CPs-SO4H involved both carbon chain decomposition and hydroxylation processes, whereas CPs-SH underwent oxidation through carbon chain decomposition.

Spatial distribution, conversion, and ecological risk assessment of hexabromocyclododecanes in the sediments of black-odorous urban rivers nationwide in China

Hexabromocyclododecanes (HBCDs) have become a global pollution problem, particularly in China-a major producer and user of HBCDs. However, little is known about the HBCD pollution status in urban rivers nationwide in China. In this study, we comprehensively investigated the pollution characteristics of HBCDs in 173 sediment samples from black-odorous urban rivers across China. Total HBCD concentrations ranged from not-detected to 848 ng/g dw, showing significant differences among the various sampling cities, but generally increasing from west to east China. This distribution pattern of HBCDs was strongly associated with the local industrial output, gross domestic product, and daily wastewater treatment capacity. α-HBCD was the predominant diastereoisomer in most sediments, with an average proportion of 63.8 ± 18.8 %, followed by γ-HBCD (23.8 ± 19.5 %) and β-HBCD (12.4 ± 6.49 %), showing a significant increase of the α-HBCD proportions relative to those in HBCD commercial mixtures and an opposite trend for that of γ-HBCD. These results suggested that HBCDs might undergo isomerization from γ- to α-HBCD and biotic/abiotic degradation with preference for γ-HBCD. Of these conversions, the microbial degradation of HBCDs was further verified by the preferential transformation of (-)-α-, (+)-β-, and (-)-γ-HBCDs and the detection of HBCD-degrading bacteria, including Dehalococcoides, Bacillus, Sphingobium, and Pseudomonas. A risk assessment indicated that HBCDs pose low to moderate risks to aquatic organisms in most black-odorous urban river sediments.

Metal(loid)s in organic-matter-polluted urban rivers in China: Spatial pattern, ecological risk and reciprocal interactions with aquatic microbiome

Black-odorous urban rivers can serve as reservoirs for heavy metals and other pollutants, in which sewage-derived labile organic matter triggering the water blackening and odorization largely determine the fate and ecological impact of the heavy metals. Nonetheless, information on the pollution and ecological risk of heavy metals and their reciprocal impact on microbiome in organic matter-polluted urban rivers remain unknown. In this study, sediment samples were collected and analyzed from 173 typical black-odorous urban rivers in 74 cities across China, providing a comprehensive nationwide assessment of heavy metal contamination. The results revealed substantial contamination levels of 6 heavy metals (i.e., Cu, Zn, Pb, Cr, Cd, and Li), with average concentrations ranging from 1.85 to 6.90 times higher than their respective background values in soil. Notably, the southern, eastern, and central regions of China exhibited particularly elevated contamination levels. In comparison to oligotrophic and eutrophic waters, the black-odorous urban rivers triggered by organic matter exhibited significantly higher proportions of the unstable form of these heavy metals, indicating elevated ecological risks. Further analyses suggested the critical roles of organic matter in shaping the form and bioavailability of heavy metals through fueling microbial processes. In addition, most heavy metals had significantly higher but varied impact on the prokaryotic populations relative to eukaryotes.