According to the EPA, drinking water should have no more than 10 mg/L of nitrate. Water with less than 10 mg/L of nitrate is considered safe to drink. This measurement will also appear as 10 ppm (parts-per-million). Nitrates are considered to be a primary water quality contaminant, meaning the contaminant levels are enforced by law. The EPA sets “maximum contaminant levels” (or MCLs) for these contaminants, as drinking water with elevated levels could potentially lead to health complications and illness. Other contaminants regulated by the EPA’s primary standards include lead, arsenic, asbestos, and bacteria like giardia and cryptosporidium.