Abnormalities in eelpout Zoarces viviparus upon chemical exposure

Area of Science:

• Marine Biology
• Environmental Toxicology
• Developmental Biology

Background:

• Elevated frequencies of abnormal embryos in female eelpout (Zoarces viviparus) are observed in areas with high anthropogenic input.
• Specific geographic locations in Denmark, Sweden, and Germany show concerning levels of embryo malformations.

Purpose of the Study:

• To investigate the potential of selected pollutants to induce abnormalities in eelpout embryos.
• To identify specific chemicals responsible for observed malformations in wild populations.

Main Methods:

• Pregnant eelpout were injected with selected pollutants: tributyltin, dioxin, pyrene, nonylphenol, tetrabromophenylether, and heptadecafluorooctanesulfonic acid.
• Embryos were examined for abnormalities, and chemical transfer to eggs/embryos was assessed.
• Effects of individual and combined chemical exposures were evaluated.

Main Results:

• Several tested chemicals were transferred to eelpout eggs and/or embryos.
• Some exposures increased the proportion of broods with over 10% abnormal or 5% malformed embryos.
• Spinal, cranial, and eye deformities were observed, mirroring natural occurrences.
• Certain exposures led to reduced female reproductive capacity and lower embryo condition index.

Conclusions:

• The study confirms that specific anthropogenic pollutants can induce developmental abnormalities in eelpout embryos.
• These findings link environmental contaminants to observed malformations in wild fish populations.
• Pollutants pose a risk to eelpout reproduction and embryonic development, impacting overall fish health.