Engineered nanomaterials in water and soils: a risk quantification based on probabilistic exposure and effect...

Area of Science:

• Environmental Science
• Ecotoxicology
• Risk Assessment

Background:

• Engineered nanomaterials (ENMs) production and use are rapidly increasing.
• Assessing environmental exposure and risks of ENMs is crucial.
• Limited studies quantify ENM release and environmental concentrations.

Purpose of the Study:

• To probabilistically quantify environmental risks of ENMs.
• To compare species sensitivity distributions with predicted environmental concentrations.
• To evaluate risks for five ENMs across four environmental compartments.

Main Methods:

• Extracted 112 data points from 60 ecotoxicological studies.
• Considered five nanomaterials: nano-silver, nano-titanium dioxide, nano-zinc oxide, carbon nanotubes (CNTs), and fullerenes.
• Assessed four environmental compartments: surface water, sewage treatment plant effluents, soils, and sludge-treated soils.

Main Results:

• Marginal risk for metal-based ENMs in surface water (e.g., 0.7% for nano-silver).
• Some risk identified in sewage treatment plant effluents (e.g., 39.7% for nano-silver, 18.7% for nano-titanium dioxide).
• No significant risk predicted for terrestrial compartments, except for a marginal value for nano-titanium dioxide in sludge-treated soils.

Conclusions:

• Environmental risks from ENMs vary significantly across different compartments.
• Sewage treatment plant effluents pose a higher risk than surface water or soils.
• Factors like ENM form, test conditions, and transformation influence risk assessment.