Mechanistic models predicting copper (Cu) toxicity to aquatic biota in natural waters require organic and inorganic water chemistry, and quantified values for Cu binding by sensitive biological receptors. In bioaccumulation experiments using larval fathead minnows (FHM; Pimephales promelas), we investigated time to asymptotic accumulation of Cu and quantified the conditional stability constants...

The biomass of Vaucheria sessilis forms algal mats in many freshwaters. There is a need to find the method of algal biomass utilization. Vaucheria sessilis is a rich source of micro- and macronutrients and can be used as a soil amendment. In the paper, the elemental composition of enriched, via bioaccumulation process, macroalga was investigated. For this purpose, two independent techniques wer...

This study concerns the bioaccumulation of the long-lived nuclear waste product 99Tc in duckweed (Lemna minor L.). 99Tc was present as the oxyanion TcO4-, being the main chemical form of technetium in aerobic water systems. In contrast with terrestrial plants, bioaccumulation in duckweed proved to be independent of the nitrate concentration in the medium. However, uptake is controlled by electr...

The present study investigated the acute toxic effects of a metal-loaded Bauxsol reagent (MLBR), containing more than 6,450 mg kg(-1) of bound metal, on the earthworm Eisenia fetida. Bauxsol is manufactured by Virotec Global Solutions of Gold Coast, Queensland, Australia. The E. fetida were exposed to 0, 10, 20, 40, 60, and 80% treatments of MLBR plus cow manure for 28 d. Good motility and no m...

Benthic macroinvertebrates have many useful properties that make possible the use of these organisms as sentinel in biomonitoring programmes in freshwater. Combined with the characteristics of the water and sediment, benthic macroinvertebrates are potential indicators of environmental quality. Thus, the spatial occurrence of potentially toxic metals (Al, Zn, Cr, Co, Cu, Fe, Mn and Ni) in the wa...

Bioaccumulation in aquatic species is a critical end point in the regulatory assessment of chemicals. Few measured fish bioconcentration factors (BCFs) are available for fragrance ingredients. Thus, predictive models are often used to estimate their BCFs. Because biotransformation can reduce chemical accumulation in fish, models using QSAR-estimated biotransformation rates have been developed. ...

Mandated efforts to assess chemicals for their potential to bioaccumulate within the environment are increasingly moving into the realm of data inadequacy. Consequently, there is an increasing reliance on predictive tools to complete regulatory requirements in a timely and cost-effective manner. The kinetic processes of absorption, distribution, metabolism, and elimination (ADME) determine the ...

Selenium is essential for most of living organisms. In normoxic to moderately hypoxic freshwaters, Se exists predominantly in the (+VI) and (+IV) oxidation states as selenate and selenite respectively, whereas in the biota it is incorporated as Se (-II) or Se (0). At low concentrations, it acts against oxidative damages, but it may be toxic at higher levels. In filter feeders, such as the fresh...

the spatial and temporal distribution of heavy metals in water, sediment and fish (dry weight basis) of buriganga river, bangladesh were determined by atomic absorption spectrophotometer. in water concentration of pb, cd, ni, cu and cr varied seasonally and spatially from 58.17 to 72.45î¼g/l, 7.08 to 12.33î¼g/l, 7.15 to 10.32î¼g/l, 107.38 to 201.29î¼g/l and 489.27 to 645.26î¼g/l, respectively. ...

Traditionally, water quality guidelines/criteria are based on lethality tests where results are expressed as a function of waterborne concentrations (e.g. LC50). However, there is growing interest in the use of uptake and binding relationships, such as biotic ligand models (BLM), and in bioaccumulation parameters, such as critical body residue values (e.g. CBR50), to predict metal toxicity in a...