The derivation of effects threshold concentrations of lead for European freshwater ecosystems

• The main objective of the present study was to derive ecologically relevant effect threshold concentrations of (dissolved) Pb for selected European Union (EU) freshwater rivers, using the 2008EU Voluntary Risk Assessment Report as a starting point and more advanced methodologies than those used in the Voluntary Risk Assessment Report. This included 1) implementing more robust quality criteria for selecting chronic toxicity data; 2) the conversion of total to dissolved Pb concentrations using a combination of an empirical equation relating inorganic Pb solubility and geochemical speciation modeling to account for effects of dissolved organic matter; 3) the use of bioavailability models for chronic toxicity for species belonging to 3 different trophic levels; and 4) the use of robust methods for large data set handling (such as species sensitivity distribution [SSD] analysis). The authors used published bioavailability models for an algal species (Pseudokirchneriella subcapitata) and a daphnid (Ceriodaphnia dubia) and developed a new model for the fathead minnow (Pimephales promelas). The research has shown that these models are also useful for, and reasonably accurate in, predicting chronic toxicity to other species, including a snail, a rotifer, midge larvae, and an aquatic plant (read-across). A comprehensive chronic toxicity data set for Pb was compiled, comprising 159 individual high-quality toxicity data for 25 different species. By applying the total dissolved conversion and the bioavailability models, normalized toxicity values were obtained, which were then entered into a SSD analysis. Based on the parametric best-fitting SSDs, the authors calculated that ecological threshold concentrations of Pb protecting 95% of freshwater species for 7 selected European freshwater scenarios were between 6.3μg dissolved Pb/L and 31.1μg dissolved Pb/L. Environ Toxicol Chem 2016;35:1310-1320.

Ämnesord

TEKNIK OCH TEKNOLOGIER  -- Miljöbioteknik -- Vattenbehandling (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Environmental Biotechnology -- Water Treatment (hsv//eng)

NATURVETENSKAP  -- Biologi -- Biokemi och molekylärbiologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences -- Biochemistry and Molecular Biology (hsv//eng)

Nyckelord

Metal bioavailability

Risk assessment

Water quality criteria

Biochemistry

Biological materials

Data handling

Dissolution

Ecology

Lead

Quality control

Toxicity

Water

Water quality

Dissolved organic matters

Freshwater ecosystem

Geochemical speciation

Pseudokirchneriella subcapitata

Risk assessment reports

Threshold concentrations

Pollution

algae

Ceriodaphnia dubia

Chironomidae

Daphniidae

Gastropoda

Pimephales promelas

Selenastrum capricornutum

Publikations- och innehållstyp

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