Site-specific hazard evaluation for improved groundwater risk assessment.

Area of Science:

• Environmental Science
• Ecotoxicology
• Hydrogeology

Background:

• Groundwater is a vital global resource, making water quality and contamination critical concerns for ecosystems and human populations.
• The WaterJPI "We-Need" project focuses on water needs, availability, quality, and sustainability, using Italian aquifers as case studies.
• Assessing groundwater contamination impacts is essential for effective resource management and environmental protection.

Purpose of the Study:

• To conduct a site-specific groundwater hazard assessment for the Cremona and Bologna aquifers in Italy.
• To evaluate the potential ecological impacts of detected contaminants (boron, fluoride, ammonium) on aquatic organisms.
• To investigate the influence of testing media on toxicity assessment outcomes.

Main Methods:

• Simulated groundwater from Cremona (CSW) and Bologna (BSW) aquifers using synthetic waters.
• Prepared synthetic waters with specific concentrations of boron, fluoride, and ammonium.
• Conducted acute toxicity tests using Daphnia magna and Fish Embryo Toxicity Tests (FET) with Danio rerio in synthetic waters and culture media.

Main Results:

• Boron, fluoride, and ammonium showed no ecological hazard effects at concentrations found in the Cremona and Bologna aquifers.
• Toxicity assessment results were dependent on the testing medium and the specific aquatic organism used.
• Significant variations in toxicity were observed between synthetic waters and standard culture media.

Conclusions:

• Groundwater contamination by boron, fluoride, and ammonium at detected levels in the studied aquifers does not present an ecological hazard.
• The choice of testing medium significantly influences ecotoxicity results, emphasizing the need for careful consideration in hazard assessments.
• Site-specific hazard assessments require adapted testing protocols that account for media and organism-specific responses for greater relevance.