Jeff Crisler, Division of Drinking and Groundwater, Ohio Environmental Protection Agency
Karen Mancl, Professor Food, Agricultural and Biological Engineering, The Ohio State University
It is rare that lead or copper is found in water sources naturally. Since household plumbing is often constructed with copper pipe and brass fittings connected by solder that may contain lead, household plumbing is the most common source of lead and copper in drinking water. In very old water systems, lead pipes and fittings can still be found. If water distributed through the system is corrosive, metals can leach into drinking water.
Lead has no benefit in drinking water. Therefore, the goal for lead levels in water is zero. Lead can cause a variety of health effects when people are exposed to excessive levels for a short period of time. These effects include interference with red blood cell chemistry, delays in normal development in babies and young children, slight deficits in attention span, hearing, and learning ability in children. Slight increases in blood pressure occur in some adults. Lifelong exposure has the potential to cause stroke, kidney disease, or cancer.
To avoid even short-term exposure, an action level of 15 parts per billion (ppb) has been set by US EPA.
The most obvious sign of copper in water is green stains that develop on plumbing fixtures. At low levels copper is an essential nutrient. Copper is found in vitamin/mineral pills. However, at higher levels people can suffer stomach and intestinal distress, liver and kidney damage, and anemia. Persons with Wilson's Disease may be more sensitive than others to the effects of copper.
To avoid even short-term exposure, an action level of 1.3 parts per million (ppm) [that is 1300 ppb] has been set by US EPA.
To guard against exposure of lead to water system customers, the U.S. Congress added the lead/copper rule to the Safe Drinking Water Act when it was amended in 1986. The rule took effect beginning in 1991. While the rule is complicated, water systems throughout Ohio have worked to protect their customers and comply with the law. To review the rule check www.epa.gov/safewater/dwh/c-ioc.html.
Since lead and copper are rarely present in the source water, water systems must work to keep lead and copper from dissolving into their water from the plumbing in people's homes. Water systems go through a series of steps to deal with lead and copper concerns.
| Step 1. Monitor, in customers' homes, water that has stood in their plumbing for at least 6 hours. In this way if the water is corrosive, the first glass of water drawn after a night of standing in contact with household plumbing will show the highest expected lead and copper levels. | |
| Step 2. If at least 90% of the required household samples are below 15 ppb lead and/or 1.3 ppm copper, the water supply is not required to treat the water to reduce corrosion. However, the system must continue to monitor for lead and copper. | Step 2. If more than 10% of the required household samples exceed 15 ppb lead and/or 1.3 ppm copper, the water supply must install water treatment equipment to reduce the corrosivity of the water. If lead exceeds 15 ppb, the water supply must also notify their customers. |