[Transfer and Fate of Polybrominated Diphenyl Ethers in an Electrical Equipment Dismantling Area Using a Multimedia Fugacity Model].

The multimedia fugacity model (Ⅲ) was used to simulate the distribution, transfer and fate of typical polybrominated diphenyl ethers (PBDEs) in air, water, soil and sediment in an electrical equipment dismantling area in eastern China. The modeling data were compared with monitored values in air, soil and sediment for validation purpose. Moreover, the transfer fluxes between different compartments were analyzed in order to infer the main transfer process.

[Effects of Acidic and Basic Modification on Activated Carbon for Adsorption of Toluene].

Activated carbons (ACs) were modified by acidic solutions (HSO, HNO, or HPO) and basic solutions (NaOH or NH·HO), then HSOmodified ACs were re-modified by basic solutions, respectively, in order to investigate the key factors of physico-chemical properties that mainly affected the adsorption of ACs. BET surface area, micropore volume, and surface functional groups were characterized and the adsorption capacity of toluene on the modified ACs was measured. Results showed that BET area,micropore area and micropore volume decreased and the acidic functional groups increased by the acidic treatment, while the basic treatment showed the opposite changing trend in the physico-chemical properties of ACs.

[Toluene, Benzene and Acetone Adsorption by Activated Carbon Coated with PDMS].

To improve the adsorption selectivity of volatile organic compounds ( VOCs) , activated carbon ( AC) was modified by polydimethylsiloxane (PDMS) and characterized by BET analysis and Boehm titration. Dynamic adsorption column experiments were conducted and Yoon-Neslon(Y-N) model was used to identify adsorption effect for toluene, beuzene and acetone on AC when relative humidity was 0%, 50% and 90%, respectively. The results showed that the BET area, micropore volume and surface functional groups decreased with the PDMS modification, and surface hydrophobicity of the modified AC was enhanced leading to a lower water adsorption capacity.

Enhanced adsorption of benzene vapor on granular activated carbon under humid conditions due to shifts in hydrophobicity and total micropore volume.

A series of hydrophobic-modified (polydimethylsiloxane (PDMS) coating) activated carbons (ACs) were developed to answer a fundamental question: what are the determinants that dominate the adsorption on ACs under humid conditions? Using column experiments, an inter-comparison among bare-AC and PDMS-coated ACs was conducted regarding the association of surface characteristics and adsorption capacity. Primary outcomes occurred in two dominating markers, hydrophobicity and total micropore volume, which played a key role in water adsorption on ACs. However, their contributions to water adsorption on ACs substantially differed under different Pwater/Pair conditions.

[Distribution and health risk of HCHs and DDTs in a contaminated site with excavation].

Air samples were collected to analyze the distribution of HCHs and DDTs around a contaminated site during its excavation. The carcinogenic risks and non-carcinogenic risks through breath exposure were studied by health risk assessment modes. The results showed that, there was an obvious seasonal variation of HCHs and DDTs in air around the excavating area.

[Pollution characteristics and ecological risk of polybrominated diphenyl ethers (PBDEs) in river sediments from an electrical equipment dismantling area].

Polybrominated diphenyl ethers (PBDEs) were determined in sediments collected from a river which through an electrical equipment dismantling area. The results showed that concentrations of PBDEs ranged from 101 to 20,400 ng · g(-1) with an average of 3,700 ng · g(-1), and BDE209 was the most dominant homologue accounted for more than 94% of all detected homologues. The concentration of PBDEs was higher in the middle of river than that in upstream and downstream and the average concentration in downstream was higher than the upstream, with a peak of concentration in the area near by dismantling industrial park.

[Pollution patterns and health risk assessment for polychlorinated biphenyls in soils from a capacitor storage site].

Concentration profiles of polychlorinated biphenyls (PCBs) and toxicity risks of dioxin-like PCBs were investigated in soils collected from a capacitor-burial site. Based on the USEPA model of human health risk assessment, cancer and non-cancer risks for these soils were also estimated when used for residential and industrial purposes. It was observed that the average concentrations of total PCBs (sigma PCBs, 22 congeners) in the soils were 6.

Distribution and ecological risk of polychlorinated biphenyls and organochlorine pesticides in surficial sediments from Haihe River and Haihe Estuary Area, China.

Polychlorinated biphenyl (PCB) and organochlorine pesticide (OCP) were analyzed in surficial sediments from the Haihe River and Haihe Estuary Area, Tianjin, China. The concentrations of [summation operator]PCBs (the sum of 32 PCB concentrations) and [summation operator]OCPs (the sum of eight OCPs concentrations) in the sediments from this area ranged from n.d.

[Pollutant distribution in organo-mineral aggregates in topsoils from a site contaminated by organochlorine pesticides].

Four different soil particle-size fractions that is clay, silt, fine sand and coarse sand ( <2 microm, 2-20 microm, 20-200 microm, > 200 microm) from the topsoils in an organochlorine pesticide (OCP) field were separated by physical method to characterize the OCPs distribution in soils and to study the effect of organic matter and mineral composition in different separates on pollutants distribution. The results show that the concentrations of HCHs and DDTs in silt with 463.1 mg x kg(-1) and 1225.

[Distribution and sources of endocrine-disrupting pesticides in Beijing Guanting reservoir].

Distribution and sources of endocrine-disrupting pesticides in Guanting reservoir were studied. The results show that pesticide values in a few sites are considerately high considering to being used as a drinking water source. The variation in concentration of pesticides among sites was expected to be caused from several pathways such as contaminants through the rivers and drainage of contaminated water from the surrounding agricultural fields.