Copper compounds, while being generally non-toxic for large mammals, are very toxic for insects and other smaller animals. It’s why they are widely used in eve

Copper compounds, while being generally non-toxic for large mammals, are very toxic for insects and other smaller animals. It’s why they are widely used in everything from marine anti-fouling paint to wood ‘pickling’ treatments. And copper compounds will form in a wide variety of acidic and anoxic environments.