Steroid hormones in the aquatic environment.

Area of Science:

• Environmental chemistry
• Ecotoxicology
• Endocrinology

Background:

• Steroid hormones are vital natural regulators of physiological processes in vertebrates.
• Both natural and synthetic steroid hormones are widely used as pharmaceuticals.
• Advances in analytical chemistry reveal widespread aquatic contamination by steroid hormones.

Purpose of the Study:

• To assess the ecotoxicological impact of steroid hormones on aquatic vertebrates.
• To investigate the effects of individual and mixed steroid hormone exposures.
• To highlight the need for further research on sources and impacts of aquatic steroid hormone pollution.

Main Methods:

• Environmental monitoring to quantify steroid hormone concentrations in rivers.
• Laboratory ecotoxicology experiments using fish and amphibians.
• Analysis of effects of individual and combined hormone exposures on reproduction.

Main Results:

• Steroid hormones, including transformation products, are ubiquitous aquatic contaminants.
• Low concentrations (sub-ng/L) of some steroid hormones adversely affect aquatic vertebrate reproduction.
• Mixtures of steroid hormones can inhibit reproduction at concentrations below individual effect thresholds.

Conclusions:

• Steroid hormones represent a significant environmental pollutant concern for aquatic ecosystems.
• Further research is crucial to identify sources, characterize complex mixtures, and assess impacts on aquatic vertebrates.
• A robust aquatic risk assessment for steroid hormones requires comprehensive understanding of their environmental behavior and effects.