Is 'Green' Gold and Silver Nanoparticle Synthesis Environmentally Friendly?

Area of Science:

• Nanotechnology
• Materials Science
• Environmental Science

Background:

• 'Green' synthesis is commonly used for gold and silver nanoparticles.
• 'Green' synthesis is often claimed to be eco-friendly compared to chemical methods.

Purpose of the Study:

• To critically evaluate the environmental claims of 'green' nanoparticle synthesis.
• To determine if 'green' synthesis is truly eco-friendly.

Main Methods:

• Review of existing literature on nanoparticle synthesis.
• Analysis of comparative life cycle assessments (LCAs) for 'green' versus chemical synthesis of gold and silver nanoparticles.

Main Results:

• Comparative LCAs suggest 'green' synthesis of gold and silver nanoparticles is not inherently eco-friendly.
• The term 'green' for these nanoparticle synthesis methods is a misnomer.

Conclusions:

• 'Green' synthesis of gold and silver nanoparticles should not be automatically equated with being environmentally friendly.
• The terms 'eco-friendly' or 'environmentally friendly' require robust, comparative cradle-to-nanoparticle life cycle assessments for validation.