We studied the toxicity of sediments downstream of lead-zinc mining areas in southeast Missouri, using chronic sediment toxicity tests with the amphipod, Hyalella azteca, and pore-water toxicity tests with the daphnid, Ceriodaphnia dubia. Tests conducted in 2002 documented reduced survival of amphipods in stream sediments collected near mining areas and reduced survival and reproduction of daph...

objective: metal concentrations in 53 soil samples of shahr-e-babak were determined.  methods: assessment of enrichment factor and geo-accumulation index revealed higher degree of contamination of cd, pb, and cu in soil samples. moreover, results of metal fractionation study revealed high amount of cd and pb are associated in weakly bounds may lead to environmental risk of these metals.  result...

heavy metal toxicity has serious adverse effects on the environment. the metal sequestering characteristics of a novel metal binding peptide (glu-cys) 11 gly+linker+hexahistidine (ec 11 :his 6 ) was investigated to determine if it can absorb cu 2+ or zn 2+ cations. molecular dynamics simulations were carried out using a model of 6 cu 2+ or zn 2+ and other ions enclosed in a fully hydrated simul...

The toxicity of metals, including mercury, is expressed differently in different media, and the addition of soluble organics to the growth medium can have a significant impact on bioassay results. Although the effect of medium composition on metal toxicity is generally attributed to its effect on metal speciation (i.e., the chemical form in which the metal occurs), the importance of individual ...

Some of metal ions are the most dangerous pollutants due to their acute toxicity and carcionogenetiy. Exposure to high concentrations of these metal ions causes lung, nasal and throat cancers. Therefore, interest and demand is increasing for metal determination in biological and environmental samples [1]. Metal ions were generally determined with atomic absortion spectrophotometry or inductivel...

Multifunctional metal chelators that can modulate the amyloid β (Aβ) peptide aggregation and its interaction with metal ions such as copper and zinc hold considerable promise as therapeutic agents for Alzheimer's disease (AD). However, specific rather than systemic metal chelation by these compounds is needed in order to limit any side effects. Reported herein are two novel small bifunctional c...

Although the toxicity of metal contaminated soils has been assessed with various bioassays, more information is needed about the biochemical responses, which may help to elucidate the mechanisms involved in metal toxicity. We previously reported that the earthworm, Eisenia fetida, accumulates cadmium in its seminal vesicles. The bio-accumulative ability of earthworms is well known, and thus the...

The biotic ligand model (BLM) is widely used to predict the toxicity of metals. There are two main principles underlying this model: 1) the concentration at the biotic ligand (BL) is directly related to the adverse effects and 2) the concentration at the BL depends on the dissolved metal concentration and the water chemistry. The latter determines the complexation of the metals with dissolved o...