Biomedical subjects

Zi-jian Wang

Publications and source records attributed to Zi-jian Wang.

8 recordsLinked to original sources

PubMed2006

[Comparison between biomimetic sampling technique using semipermeable membrane device and bioconcentration in caged fish for polycyclic aromatic hydrocarbons].

Semipermeable membrane device (SPMD) was recently accepted to estimate the time-integrated concentrations of bioavailable hydrophobic organic compounds (HOCs) in a similar manner as lipophilic bioconcentration. However few field researches were carried out to verify the similarities of SPMD and fish in concentrating HOCs from water. In present work, SPMD and caged crucian carps (Carassius auratus) were deployed side-by-side at five sites in Meiliang Bay, Taihu Lake for 32 days and concentrations of polycyclic aromatic hydrocarbons (PAHs) in SPMD and fish were analyzed. The results showed that the composition of PAHs and relative concentration of individual PAH in SPMD and fish were quite similar. There was significant correlation between bioconcentration factors (lg BCF) and device concentration factors (lg DCF) for concentrations of PAHs (p < 0.0001). However in a quantitative analysis, lipid-normalized concentrations of PAHs in SPMD and fish were similar, and the ratios of the concentrations of PAHs in fish and SPMD were ranged from 0.47 to 4.12. In summary, SPMD could be the surrogate to estimate PAHs levels in fish in fresh water lake.

Animals↗

PubMed2006

[Genotoxicity of soil irrigated by wastewater using umu/SOS test].

umu/SOS test is used to screen the accumulation of genotoxic substances in soil irrigated with wastewater in urban Beijing. The relative genotoxicity is evaluated based on the weight of soil used for extraction that could result in a positive reaction (or the induction ratio R equals 2) and the characteristics of genotoxic substances could be evaluated by the slop of linear part of the dose/effect relationship, R reaches the maximum when the amount of soil in each cell is about 10 mg. In a case study on a wastewater or reclaimed water irrigation area, the genotoxicity of soil samples could be observed and it may be attributed to the accumulation of PAHs, according to relevant information.

DNA Damage↗

PubMed2006

[Comparative study on accumulation of Ah-receptor agonists in contaminated soil based on EROD bioassay and chemical analysis].

The potential ecological risk by wastewater or reclaimed water for irrigation is of great concerns in recent years, but little work was done on the chronic toxicities through long term accumulation of persistent organic chemicals in soil. In present work, concentration of Ah-receptor agonists in soil organic extract was measured by an ethoxyresorfin O-deethylase (EROD) bioassay, which was calibrated and expressed by the 2, 3, 7, 8-tetrachlorodibenzo- p-dioxin (2, 3, 7, 8-TCDD) toxic equivalent (TEQbio). Simultaneously, 16 PAHs in soil were analyzed and their TEQs (total as TEQ(PAHs)) were calculated according to their toxic equivalent factors (TEFs) cited from literature. By bioassay, it was found that the concentration level of Ah-receptor agonists in soil irrigated using reclaimed water could be as high as 97.4 ng/kg, which was obviously higher than that in background soil using ground water irrigation regime (56.0 ng/kg). In comparing the results from bioassay and chemical analysis, the percentage of TEQ(PAHs) in TEQbio increased from 10.3% in background soil to 78.6% in the soil irrigated by reclaimed water. Use of reclaimed water for irrigation could result in the accumulation of Ah-receptor agonists in soil,and a major part of them in this case could be attributed to the accumulation of 16 priority PAHs in soils.

Animals↗

PubMed2005

[Assessing the ecological risk of effluents from different advanced treatment units by using a battery of bioassay].

In this paper, effluents from different advanced treatment units, which were reclaimed for Olympic Park, were assessed regarding to the removal efficiencies of the technologies on acute toxicants, Ah-acceptor chemicals and estrogenic substances by using a battery of bioassays. The results showed that advanced treatments using ultra-filtration and activated carbon absorption were suitable for removal of toxic organic substances from STP effluent. Activated carbon absorption was the most effective technology to remove acute toxicants and Ah-acceptor chemicals, and the removal efficiency of Ah-acceptor chemicals reached 98%. Ultra-filtration was suitable for removing nonpolar acute toxicants and polar estrogenic chemicals. Nonpolar fraction extracted from water after ultra-filtration treatment showed 100% percentage survival of cell in the acute toxic assay. E2-TEQ was reduced from 0.13 pmol x L(-1) to 0.04 pmol x L(-1) in the polar fraction extracted from water after ultra-filtration. Treatments with micro-filtration and osmosis did not manifest sufficient efficiencies for removal of toxic organic substances. In complex matrix, interactions may occur among different toxic components to interfere the bioassay results. Therefore fractionation of organic concentrate before bioassay is necessary.

Biological Assay↗

PubMed2005

Distribution, sources and potential toxicological significance of polycyclic aromatic hydrocarbons(PAHs) in Guanting Reservoir sediments, China.

The Guanting Reservoir lost its function as the second biggest drinking water source for Beijing due to the pollutions from the upstream flow of Yongding River in 1997. From 1998, lots of studies were carried out to renew the function of Guanting Reservoir as domestic drinking water source before 2008 Olympic Games. This is the first time that polycyclic aromatic hydrocarbon concentrations in the surface sediment of Guanting Reservoir have been analyzed. A distinctive spatial distribution of PAHs was observed. Sediments from four sites along Inlet of Yongding River to reservoir bam had PAHs concentrations of 1377-2855 microg/g dw in descending order. The composition of PAHs is investigated and used to assess petrogenic, combustion and naturally derived of the sediments samples of Guanting Reservoir. Special PAHs ratios, such as phenanthrene/anthracene (P/A) and fluoranthene/pyrene (FI/Pyr) were calculated to assess the relative importance of different origins. The data confirmed a relatively high level of petrogenic contamination in four sites. These high PAHs levels were associated with the input of untreated and partially treated industrial sewage. In addition, the concentrations of PAHs compounds of samples indicated that sediments of reservoir were most likely to pose potential biological impairment.

Chemical Fractionation↗

PubMed2005

[New method to assess phosphorus bioavailability in the sediments and soils].

A new method to assess phosphorus bioavailability in the sediments and soils was developed by using a homemade iron oxide/ cellulose acetate membrane(FeO/CAM). The results show that the amount of bioavailable phosphorus(FeO-P) desorbed from the sediment and soil increased with the shaking time,and FeO-P desorption would come to equilibrium after 16 ot 20h. With the increase of the ratio between soil mass and water volume, the quantity of the desorbed FeO-P would decrease and then went planar after 20 to 30g/L. The quantity of the desorbed FeO-P had no significant difference between the FeO/CAMs of 20 to 30cm2. The dynamics of FeO-P desorption from the sediments and soils would be accelerated by appropriately increasing the shaking frequency. In short, FeO/ CAMs overcome many disadvantages of iron oxide impregnated filter paper and are easy to be commercialized; therefore it may have a better future in the application to assessing phosphorus hioavailability in the sediments and soils.

Biological Availability↗

PubMed2004

Responses of antioxidative enzymes to accumulation of copper in a copper hyperaccumulator of Commoelina communis.

Discovery of a copper hyperaccumulator is very important for phytoremediation of copper-contaminated soil. In the present study a link was established between the copper accumulation in hyperaccumulator and that in nonaccumulator species of Commelina communis and its responses of antioxidative enzymes, including superoxide dismutase, guaiacol peroxidase, and ascorbate peroxidase. It was verified that copper exerted little physiological damage to copper hyperaccumulator species of Commelina communis at copper accumulation of >1,000 microg/g in dry leaf tissue. However, in nonaccumulator species of Commelina communis superoxide dismutase, guaiacol peroxidase, and ascorbate peroxidase were activated, and malondialdehyde content was increased, which were symptoms of physiological damage by copper intoxication. Therefore, antioxidative enzymes can be used as an indicator of copper toxicity before the visible symptoms can be observed.

Ascorbate Peroxidases↗

PubMed2004

[Preliminary health risk assessment of heavy metals in drinking waters in Beijing].

Concentrations distribution of the Cu, Hg, Cd, As in drinking water in the 8 city districts and 10 counties in Beijing was studied based on a total of 120 random samples. Health risks associated with 4 metals in drinking water were assessed using USEPA health risk assessment model. The results showed that the concentrations of the heavy metals in drinking water in Beijing ranged from 0.81 to 6.96 micrograms.L-1 for Cu, 0.34-0.82 microgram.L-1 for Cd, 0.10-0.74 microgram.L-1 for Hg and 0.19-3.02 micrograms.L-1 for As. Among the health risks caused by the carcinogens in drinking water, the largest risk associated with As should be in Tongzhou County (2.0 x 10(-5).a-1) and that with Cd should be in Changping County (2.3 x 10(-6).a-1), while both were significantly lower than the maximum allowance levels recommended by ICRP(5 x 10(-5).a-1). Among the non-carcinogenic risks in drinking water, the largest risk was the risk associated with Hg, followed by Cu. The non-carcinogenic risks levels ranged from 10(-8) to 10(-9), much lower than the maximum allowance levels recommended by ICRP.

China↗