Wen-Jing Wu

Residues, Distributions, Sources, and Ecological Risks of OCPs in the Water from Lake Chaohu, China

The levels of 18 organochlorine pesticides (OCPs) in the water from Lake Chaohu were measured by a solid phase extraction-gas chromatography-mass spectrometer detector. The spatial and temporal distribution, possible sources, and potential ecological risks of the OCPs were analyzed. The annual mean concentration for the OCPs in Lake Chaohu was 6.99 ng/L. Aldrin, HCHs, and DDTs accounted for large proportions of the OCPs. The spatial pollution followed the order of Central Lakes > Western Lakes > Eastern Lakes and water area. The sources of the HCHs were mainly from the historical usage of lindane. DDTs were degraded under aerobic conditions, and the main sources were from the use of technical DDTs. The ecological risks of 5 OCPs were assessed by the species sensitivity distribution (SSD) method in the order of heptachlor > γ-HCH > p,p′-DDT > aldrin > endrin. The combining risks of all sampling sites were MS > JC > ZM > TX, and those of different species were crustaceans > fish > insects and spiders. Overall, the ecological risks of OCP contaminants on aquatic animals were very low.

Levels, Distribution, and Health Risks of Polycyclic Aromatic Hydrocarbons in Four Freshwater Edible Fish Species from the Beijing Market

We first estimated the content of polycyclic aromatic hydrocarbons (PAHs) in the brain, liver, bladder, roe, and muscle of four species of edible freshwater fish from the Beijing market. The distribution characteristics of PAHs in these tissues and organs were analyzed to determine their health risks to humans. The results showed that the residual levels of wet weight and lipid-normalized weight ∑PAHs in various tissues of these fish ranged from 0.51 ng·g−1 to 28.78 ng·g−1 and from 93.62 ng·g−1 to 8203.43 ng·g−1, respectively. The wet weight contents of ∑PAHs were relatively higher in the brain and lower in the liver and muscle. But the differences were not significant. And the differences of lipid-normalized weight PAHs were significant, which in the bighead carp were found significantly the highest, followed in crucian carp, and the lowest in grass carp and carp. The contents of ∑PAHs were the highest in the liver and the lowest in the brain. In the tissues with a higher lipid content, higher residual levels of PAHs were found. The carcinogenic risks for humans from residual ∑PAHs in the various fish tissues were far below 10−5.

Effects of cetyltrimethylammonium chloride on uptake of pyrene by fish gills.

Laboratory experiments were carried out to study the effects of cationic surfactant cetyltrimethylammonium chloride (CTAC) on the uptake of pyrene by fish gills. The uptake (including adsorption) of pyrene by gills of the color carp (C.carpio var. color) exposed to 20–100 μg/L pyrene in the presence or absence of 0.2–1.0 mg/L CTAC were determined. The sorption of pyrene by mucus was preliminary studied using a four-step sequential extraction procedure. Fish gills were extracted with H2O, 0.01 M CaCl2, CH3OH and a mixture of 1:1 n-C6H14/CH2Cl2 in sequence. Results showed that pyrene mostly accumulated in mucus and on the surface of gills tissue; the cationic surfactant CTAC significantly enhanced these accumulation or adsorption on the fish gills (not in gills). CTAC could affect the bioavailability of pyrene in aquatic systems.

Distribution, partitioning and inhalation exposure of perfluoroalkyl acids (PFAAs) in urban and rural air near Lake Chaohu, China

To investigate the distribution, partitioning, and inhalation exposure risks of perfluoroalkyl acids (PFAAs), gaseous and particulate samples were collected monthly between September 2013 and September 2015 in urban and rural areas near Lake Chaohu. Twelve PFAAs were determined by liquid chromatography-mass spectrometry. The mean concentrations of PFAAs in the gaseous phase and the particulate phase were 40.31 ± 31.47 pg/m3 and 63.26 ± 41.87 pg/m3, respectively. Perfluorobutanoic acid (PFBA) was the predominant contaminant in the gaseous phase (32.56% ± 9.28%), while perfluorooctanoic acid (PFOA) was the main contaminant in the particulate phase (33.21% ± 18.69%). The ratios of gaseous to particulate distribution ranged from 0.01 to 16.75. The gaseous-particulate partitioning coefficients, ranging from 0.01 to 23.41 ± 10-2 m3/μg, were significantly correlated with PM10 concentrations and meteorological conditions, such as temperature and air pressure. The inhalation exposures of PFOA and PFOS were 1.94-60.2 pg/(kg·d) and 0.30-4.22 pg/(kg·d), respectively. The carcinogenic risk of PFOA for urban males was the highest and that for rural females was the lowest; the risks were lower than the acceptable level (10-6) defined by the US Environmental Protection Agency (USEPA). The non-carcinogenic risks of PFOA and PFOS were far below one.

Effects of sodium dodecylbenzenesulfonate on uptake of pyrene by fish gills

Laboratory experiments were carried out to study the effects of anionic surfactant sodium dodecylbenzenesulfonate (SDBS) on the uptake of pyrene by fish gills. The uptake (including adsorption) of pyrene by gills of the color carp (C. carpio var. color) exposed to 20–100 μg/L pyrene in the presence or absence of 0.2–6.0 mg/L SDBS were determined. The sorption of pyrene by mucus was preliminary studied using a four-step sequential extraction procedure. Fish gills were extracted with H2O, 0.01 M CaCl2, CH3OH and a mixture of 1:1 n-C6H14/CH2Cl2 in sequence. Results showed that SDBS significantly affected these accumulation or adsorption on the fish gills (not in gills). SDBS could affect the bioavailability of pyrene in aquatic systems.