Lead seeps into the water supply from the lead pipes, solder and fixtures used extensively across the United States. There is no safe level of lead exposure, especially for children, who can suffer harmful and potentially chronic effects ranging from stomach pain to brain damage.

Magnesium is a mineral that enters water when rain soaks into the ground, running through sand, soil, and rock. The presence of magnesium creates hard water. Although this is not a direct health hazard, magnesium in water can cause buildup in pipes, shortened life spans for your appliances, increased soap and detergent use, dry skin, dull hair, and spotted dishes.

Nitrates are essential for food, flowers and greener lawns, which makes them a major ingredient in most fertilizers. Although nitrates are naturally occurring in soil, overuse of fertilizer is the largest cause of contamination. Nitrates spread on lawns and fields can move quickly through soil and grow more concentrated in groundwater, creating potential health risks for everyone, especially infants and pregnant women.

PFOA and PFOS are artificial chemicals that were widely used in the manufacturing of industrial and consumer products until the year 2000. Prior to phasing them out of production, PFOA and PFOS were released into the environment and contaminated drinking water supplies, especially near manufacturing sites. The presence of these chemicals in drinking water may result in health issues including developmental effects, cancer, liver damage, immune disorders and thyroid imbalance.