Copper can be introduced into a water supply by corrosion in your household plumbing system. Short-term exposure to higher doses can cause gastrointestinal distress, such as vomiting, nausea and diarrhea. Long-term exposure can lead to liver and/or kidney damage. Children under one year of age and people with Wilson’s Disease should consult their doctor since they might have more trouble maintaining proper levels of copper in their organism, and can be more exposed to its toxicity.