The CDC states that copper is a natural metal found in soil, rock, plants, water and animals. All living things, including humans, need copper in their diet for good health, so trace amounts in the body are not harmful. However, excess amounts of copper can cause health problems.
Exposure to a higher amount of copper can cause irritation of the nose, eyes, mouth and cause headaches, among other symptoms. The Agency for Toxic Substances and Disease Registry’s full public health statement on copper highlights exposure effects.
EPA regularly reviews the use of copper as an antimicrobial and assesses its risk to human health and the environment and strictly regulates antimicrobial uses of copper.