Assessment of contaminants of emerging concern in European apex predators and their prey by LC-QToF MS wide-scope target analysis.

Apex predators are good indicators of environmental pollution since they are relatively long-lived and their high trophic position and spatiotemporal exposure to chemicals provides insights into the persistent, bioaccumulative and toxic (PBT) properties of chemicals. Although monitoring data from apex predators can considerably support chemicals' management, there is a lack of pan-European studies, and longer-term monitoring of chemicals in organisms from higher trophic levels. The present study investigated the occurrence of contaminants of emerging concern (CECs) in 67 freshwater, marine and terrestrial apex predators and in freshwater and marine prey, gathered from four European countries.

Evaluation of acute-to-chronic ratios of fish and to predict acceptable no-effect levels.

Background: Acute-to-chronic extrapolation is an important approach to predict acceptable no-effect levels from acute data which has some uncertainties, but is valuable for risk assessment of chemical substances. With regard to the still limited and heterogenic data of chronic fish tests, conclusions on aquatic hazard estimation need to be checked and the question arises whether the chronic toxicity to fish can be adequately derived from acute data. A comprehensive dataset including ecotoxicological studies of 203 substances was used to investigate acute-to-chronic ratios (ACR) for both fish and .

Evaluation of the integrated testing strategy for PNEC derivation under REACH.

Species sensitivity evaluation represents an approach to avoid chronic toxicity testing of aquatic vertebrates in accordance with the animal welfare concept of the EU chemicals regulation. In this study a data set of chemicals is analysed for relative species sensitivity between Daphnia and fish in chronic testing to evaluate under what condition chronic fish tests can be waived without underestimating the environmental hazard. Chronic fish toxicity is covered in 84% of the evaluated substances by the chronic invertebrate test and an assessment factor of 50.

The Dessau workshop on bioaccumulation: state of the art, challenges and regulatory implications.

Bioaccumulation plays a vital role in understanding the fate of a substance in the environment and is key to the regulation of chemicals in several jurisdictions. The current assessment approaches commonly use the octanol-water partition coefficient (log ) as an indicator for bioaccumulation and the bioconcentration factor (BCF) as a standard criterion to identify bioaccumulative substances show limitations. The log does not take into account active transport phenomena or special structural properties (e.

Problems faced when evaluating the bioaccumulation potential of substances under REACH.

The identification and regulation of substances that combine persistence, bioaccumulation potential, and toxicity ("PBT" substances) is one central aspect of the European chemical legislation REACH (Registration, Evaluation, Authorisation, and Restriction of Chemicals), because these substances may elicit adverse long-term effects after release to the environment. The determination of a substance that has persistence, bioaccumulation potential, and toxicity is based on a set of distinct cutoff criteria identified in Annex XIII of the REACH regulation. Regarding the bioaccumulation potential, the evaluation is focused on the substance's bioconcentration factor as single decisive criterion.

Heavy metal toxicity to Lemna minor: studies on the time dependence of growth inhibition and the recovery after exposure.

Environmental concentrations of toxic substances are not necessarily constant but fluctuate over time. Periods of intense exposure might be followed by episodes with a relatively low or no exposure, in principle allowing exposed organisms to recover from toxic injury. The growth reproduction assay with the limnic vascular plant Lemna minor allows for convenient studies on the time dependence of the aquatic toxicity of chemicals.