Ecotoxicology

Ecotoxicology is the scientific study of the environmental effects of toxic substances on ecosystems. It examines how chemicals, pollutants and other stressors influence the survival, growth, reproduction and behavior of organisms, and how these effects propagate through populations and communities. The field covers aquatic and terrestrial environments, including water, soil and sediment, and considers both single substances and mixtures, as well as short- and long-term exposures. Its aim is to understand ecological risk and inform protection of biodiversity and ecosystem services.

Research methods combine laboratory tests, field studies and computational models. Model organisms commonly used in aquatic ecotoxicology include Daphnia magna, algae such as Pseudokirchneriella subcapitata, and fish like fathead minnows (Pimephales promelas) or rainbow trout. Endpoints range from acute lethality (LC50, EC50) to chronic effects on growth, reproduction and development, as well as biomarkers and behavioral changes. Mesocosm experiments and field surveys help illuminate real-world exposure and ecological interactions.

Risk assessment integrates exposure data with dose–response relationships to estimate potential effects on populations and communities. Challenges include mixture toxicity, bioaccumulation and trophic transfer, which can produce additive, synergistic or antagonistic effects. Ecotoxicology informs regulatory decisions through standardized testing and data synthesis, guiding environmental quality standards, risk boundaries and remediation priorities. International guidelines from OECD and various national agencies support harmonized methods.

Overall, ecotoxicology provides the scientific basis for preventing pollution, protecting biodiversity and maintaining ecosystem services in the face of chemical stressors and changing environmental conditions.