Antimicrobial silver: uses, toxicity and potential for resistance

Area of Science:

• Environmental science
• Microbiology
• Toxicology

Background:

• Silver compounds, including silver ions and nanoparticles, are extensively utilized in various biological applications due to their potent antimicrobial properties.
• While silver ions present minimal immediate human health risks, the toxicity and environmental impact of silver nanoparticles remain largely unclarified.
• The widespread use of silver-based products raises concerns about increased environmental silver release and its ecological consequences.

Purpose of the Study:

• To provide a comprehensive overview of the applications, toxicity, and environmental spread of silver compounds.
• To elucidate bacterial silver resistance mechanisms and their dissemination.
• To highlight the importance of understanding silver toxicity and resistance for safe applications and ecological impact assessment.

Main Methods:

• Literature review of existing studies on silver compound applications.
• Analysis of research on silver toxicity mechanisms in biological systems.
• Investigation of bacterial silver resistance determinants and their genetic basis.

Main Results:

• Silver ions exhibit strong antimicrobial activity with low immediate human health risks, driving widespread product use.
• The risks associated with silver nanoparticles are not fully understood, yet their use may increase environmental silver levels.
• Silver resistance genes are prevalent in environmental and clinical bacteria, often located on mobile genetic elements facilitating horizontal gene transfer.

Conclusions:

• Detailed knowledge of silver toxicity and bacterial resistance mechanisms is essential for optimizing silver-based applications.
• Understanding these mechanisms is critical for assessing and mitigating the impact of silver on human health and ecosystems.
• Further research is needed to clarify the risks of silver nanoparticles and their environmental fate.