The distribution in water and sediment, the sources/sinks and the risk of perfluorinated compounds (PFCs) in Lake Taihu, China were investigated. The total PFCs concentration was 164 to 299 ng L(-1) in water and 5.8 to 35 ng g(-1) (dw) in sediment. The highest concentrations of perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) in water were 29.2 ng L(-1) and 136ngL(-1). PFOS was la...

An exhaustive study of the distribution of butyltin species was conducted in the sediment of the Saguenay Fjord (Canada), a semi-enclosed marine system with sediment permanently submitted to sub-Arctic cold conditions. Concentrations of total butyltins (tributyltin [TBT], dibutyltin, and monobutyltin) ranged from 6 to 288 ng Sn/g dry weight and were typical of those reported for contaminated co...

A growing body of evidence shows that the effectiveness of in-situ activated carbon (AC) amendment to treat hydrophobic organic contaminants (HOCs) in sediments can be reliably predicted using a mass transfer modeling approach. This study analyzes available field data for characterizing AC-sediment distribution after mechanical mixing of AC into sediment. Those distributions are used to develop...

Baihua Reservoir in Guizhou Province, China, experienced serious Hg contamination from Guizhou Organic Chemical Plant (GOCP) between 1971 and 1997. However, the biogeochemical cycling of Hg in this reservoir is not well studied. Sediment cores were collected in fall 2002, spring 2003 and in spring and fall 2004. THg and MeHg concentrations in all sediment profiles ranged from 0.26 to 38.9 mg/kg...

This work investigates arsenic mobility, bioavailability and toxicity in marine port sediments using chemical sequential extraction and laboratory toxicity tests. Sediment samples were collected from two different Mediterranean ports, one highly polluted with arsenic and other inorganic and organic pollutants (Estaque port (EST)), and the other one, less polluted, with a low arsenic content (Sa...

the shape of a submerged vane is a major factor in the design of a vane system and affects the performance and secondary currents generated by the vanes. this study investigated the effect of five vane shapes on bed sediment processes (local scour at the leading edge and transverse distribution of sediment downstream of the vanes) at four flow intensities for a total of 20 experiments. the resu...

the levels of 19 organochlorine pesticides (ocps) in surface water and under water sedimentsfrom tanks located nearby the prime agricultural areas of kanyakumari district, tamil nadu, india wereinvestigated to evaluate their pollution risks. a total of 36 surface water samples at 9 sampling sites and27 sediment samples at 9 sampling stations were collected from tanks, which were the water sourc...

Title of Dissertation: THE IMPORTANCE OF PHYSICAL MIXING AND SEDIMENT CHEMISTRY IN MERCURY AND METHYLMERCURY BIOGEOCHEMICAL CYCLING AND BIOACCUMULATION WITHIN SHALLOW ESTUARIES Eun-Hee Kim, Doctor of Philosophy, 2004 Dissertation Directed By: Professor Robert P. Mason, Marine Estuarine Environmental Science The objective of this study was to examine, using mesocosm experiments, the long-term ef...