Ecotoxicity evaluation of a liquid detergent using the automatic biotest ECOTOX

Area of Science:

• Environmental Science
• Ecotoxicology
• Aquatic Biology

Background:

• Synthetic detergents are prevalent aquatic pollutants from domestic, institutional, and industrial use.
• Understanding detergent toxicity is crucial for aquatic ecosystem health.

Purpose of the Study:

• To evaluate the toxicity of a liquid dishwashing detergent on the freshwater alga Euglena gracilis (E. gracilis).
• To assess both short-term and long-term effects on various E. gracilis physiological parameters.

Main Methods:

• Utilized the automatic biotest ECOTOX for toxicity assessments.
• Monitored Euglena gracilis (E. gracilis) parameters: motility, swimming velocity, gravitactic orientation, cell compactness, and cell growth.
• Conducted short-term (1-hour) and long-term exposure experiments.

Main Results:

• Short-term exposure (1h) caused maximum adverse effects on motility, velocity, and cell shape, with some recovery observed later.
• Long-term exposure led to significant disturbances in E. gracilis.
• Motility, cell growth, and cell compactness were the most sensitive parameters, with EC50 values of 0.064%, 0.18%, and 2.05% respectively.
• Detergent exposure impaired gravitactic orientation at higher concentrations (EC50 for upward swimming: 1.75%, r-value: 2.52%).

Conclusions:

• Liquid dishwashing detergent poses significant ecotoxicological risks to aquatic organisms like Euglena gracilis (E. gracilis).
• Motility and growth are key indicators of detergent stress in E. gracilis.
• Long-term exposure effects are more severe than short-term effects, emphasizing the need for careful detergent management in aquatic environments.