The European Chemicals Agency (ECHA) has released a detailed assessment report outlining the regulatory needs for silver and its compounds. This comprehensive evaluation is aimed at identifying and managing potential risks associated with these substances, particularly focusing on their environmental and human health impacts.
Substances Covered
The report covers 43 silver compounds, including both simple and complex forms, and details their chemical structures, registration types, and tonnage bands. Some of the key substances evaluated are:
- Silver nitrate (AgNO3)
- Silver chloride (AgCl)
- Silver carbonate (Ag2CO3)
- Silver bromide (AgBr)
- Silver iodide (AgI)
- Elemental silver (Ag) in various forms
Human Health Hazards
Several silver compounds have been identified as potential reproductive toxins. Notably, silver metal and its nanoparticle forms, silver nitrate, and other highly soluble silver compounds are suggested for further regulatory action to address reproductive toxicity. Extended one-generation reproductive toxicity studies and new in vivo toxicokinetics data have reinforced concerns about these substances.
Environmental Hazards
Silver compounds are known for their aquatic toxicity, leading to classifications under various hazard categories. Silver nitrate and silver metal are under particular scrutiny due to their widespread industrial, professional, and consumer uses which pose significant exposure risks.
Proposed Actions
ECHA proposes several regulatory actions, including:
- Compliance Checks (CCH): For silver metal, silver carbonate, and subgroup 2 silver compounds to ensure data requirements are met.
- Harmonised Classification and Labelling (CLH): Group approaches for reproductive toxicity classification.
- Occupational Exposure Limits (OEL): Setting EU-wide exposure limits for workers handling silver compounds.
- Substance Evaluation (SEv): Investigating endocrine disruption potential and thyroid toxicity.
Biocidal Uses and Non-Approval Decisions
The report also addresses the use of silver compounds as biocidal substances. Several silver-containing biocides have been evaluated, with some facing non-approval decisions due to insufficient efficacy. Coordination with the European Food Safety Authority (EFSA) has been undertaken to ensure consistent risk assessment methodologies for biocidal products used in food contact materials.
Conclusion and Future Steps
ECHA's assessment emphasises the need for robust regulatory frameworks to manage the risks associated with silver and its compounds. The proposed actions aim to enhance worker safety, protect environmental health, and ensure that these substances are used responsibly across various sectors. The report highlights the importance of continuous monitoring and data generation to keep regulatory measures up-to-date with emerging scientific evidence.
