Solvent toxicity to amphibian embryos and larvae

Area of Science:

• Environmental Toxicology
• Amphibian Biology

Background:

• Organic micropollutants pose risks to aquatic life.
• Hydrophobic micropollutants require organic co-solvents for water dissolution.
• Understanding co-solvent toxicity is crucial for ecological risk assessment.

Purpose of the Study:

• To evaluate the toxicity of methanol, methylene chloride, DMSO, acetone, and ethanol on common frog (Rana temporaria) embryos and tadpoles.
• To determine safe concentrations of these solvents when used as co-solvents for micropollutant studies.

Main Methods:

• Exposure of Rana temporaria embryos (with and without jelly coats) and tadpoles to various concentrations of selected organic solvents.
• Mortality rate assessment for both life stages and different solvent exposure conditions.

Main Results:

• Embryos showed higher mortality rates than tadpoles across tested solvents.
• Jelly-coated embryos were more sensitive to solvent toxicity, except for acetone.
• Safe co-solvent concentrations were identified: <= 0.001 ml/l for embryos (Acetone, DMSO, Methylene Chloride) and <= 0.01 ml/l for tadpoles (Ethanol, Acetone, Methylene Chloride).

Conclusions:

• Solvent choice and concentration are critical when studying micropollutant toxicity in aquatic models.
• Acetone, DMSO, and methylene chloride demonstrate potential as effective and relatively safe co-solvents for frog embryo studies.
• Ethanol, acetone, and methylene chloride are suitable co-solvents for tadpole studies within specified concentration limits.