U.S. EPA’s Lead & Copper Rule Underscores Very Different Toxicological Profiles for Lead and Copper

by Carrie Claytor, CDA

Lead in Drinking Water Concerns Grip North America

Concerns about the impact of Flint, Michigan drinking water on human health arose in 2015 after the city changed its water source from Lake Huron (which was treated with corrosion control chemicals) to the Flint River (which was not treated adequately for corrosion control). Corrosive waters from the Flint River caused aging lead pipes to leach into the water supply, resulting in toxic levels of lead in drinking water. Between six and twelve thousand children may have been exposed and since lead toxicity can result in permanent adverse health effects, especially in young children, a state of emergency was declared.

Elevated lead in drinking waters from aging lead plumbing materials is a problem across North America. A 2016 review of the U.S. Environmental Protection Agency’s (USEPA) enforcement data by USA Today revealed nearly two thousand drinking water systems serving six million people in all fifty states have experienced excessive or harmful levels of lead, in fact 373 of these systems failed repeatedly for excessive lead. In Canada, water toxicity experts estimate that at least 200,000 households are at risk of being exposed to lead in drinking water.

The “Lead and Copper Rule”

To protect the quality of public drinking waters, the U.S. Congress passed The Safe Drinking Water Act and The Reduction of Lead in Drinking Water Act. An amendment to the Safe Drinking Water Act known as the Lead and Copper Rule was enacted by USEPA because both lead and copper are common plumbing materials and the leaching of both of these metals can be controlled with water treatment techniques.

It is important to understand that the toxicological profiles of lead and copper resulting from drinking water exposure are very different, especially since they are both regulated under the same Lead and Copper Rule. The bottom line is this: because it is toxic even at extremely low levels, the lead action level set in the Lead and Copper Rule is only 0.015 parts per million (15 parts per billion). This is eighty seven times less than the 1.3 parts per million action level level set for copper.

While the Lead and Copper Rule mandates corrosion control for both types of pipes, additional requirements are necessary only for lead pipes. These include:

  • Consumer notices about lead by public water utilities;
  • Consumer confidence reports about health risks of lead in drinking water;
  • Public education for consumers whose drinking water exceeds 15 parts per billion lead;
  • Lead service line replacement for water systems that fail to meet 15 parts per billion lead after corrosion control treatment; and,
  • Extra precautions for large drinking water systems planning to switch to a new drinking water source (this last provision was enacted after the Flint crisis).

Different Toxicological Profiles

While lead and copper plumbing materials have been delivering water to communities for thousands of years, researchers learned only in the 20th century that these two materials have very different toxicological profiles. Thus, even though they are both regulated under the same regulatory framework of the Lead and Copper Rule, lead and copper differ greatly both in the types of adverse health effects that may arise following drinking water exposure and the concentrations at which these effects could occur.

  • Copper is an essential trace element, necessary, like some other metals, in the daily human diet to maintain good health because of the vital life-support functions that it provides. Without adequate copper intake humans get sick. Copper is essential to the healthy development and regulation of red blood cells, iron, cholesterol, glucose, immune systems, and the destruction of damaging free-radicals. A small amount of dietary copper should be ingested every day for good human health. The need for dietary copper has been acknowledged by health authorities around the world. The evidence suggests that dietary copper deficiency is a worldwide problem, while the incidence of adverse effects due to excess copper is relatively infrequent.
  • Lead is a neurotoxin that can cause long-term health effects, even at very low exposure levels. No amount of lead in children's blood is considered safe by any health authority. The USEPA has set a goal of “zero” parts per million of lead in drinking water because no safe level of exposure is known. And as of 2014, it became illegal to install new pipes, pipe fittings, other plumbing fixtures and solders that are not "lead free” (i.e., containing more than 0.25% lead).

Copper Tube Replaces Lead

Flint’s water quality experts decided early this year to replace approximately 15,000 lead service lines with copper . Several other major U.S. and Canadian cities either plan to or have recently implemented replacement programs of various scopes (e.g., Lansing, Michigan; Madison and Milwaukee, Wisconsin; Louisville, Kentucky; and Toronto, Ontario).

Experts are predicting that many municipalities, both large and small, will be coming forward with concerns regarding lead in their drinking water systems. If municipal water utility authorities and building owners across North America accelerate lead service line replacement programs, copper tube would likely be the replacement material of choice in a large majority of these systems. Today, some 80% of all water service installations, repairs and replacements in North America are made with copper.

Copper is the Best Plumbing Material for Potable Water

At a time when the U.S. plumbing industry is permitted to use only trace amounts of lead (less than 0.25% lead) in new plumbing materials, copper tube and fittings and no-lead copper alloy valves, fittings and components, joined with lead-free solders or flameless, solderless joining systems offer the best in lead-free plumbing performance. But, lead is only one regulated contaminant that can enter drinking water from the materials used in potable water systems. Other metals, plastics, and concrete all have the potential to leach small amounts of contaminants that are regulated under the Safe Drinking Water Act. Unlike copper, most of these regulated contaminants do not offer any health benefit or are not essential. Because of this, copper continues to fulfill its position as the superior plumbing material for drinking water – because of its corrosion resistance, formability, joinability, durability, dependability, light weight, economy, recyclability and safety.