Lead Leaching vs Plastic Leaching vs Copper Leaching: What's Safe?

All piping materials leach substances into drinking water to some degree, but what are the effects on water quality and human health? While lead pipes were banned in 1987, millions are still in use. Today, plastic pipes and copper pipes are most commonly installed. Leaching from all pipes could pose risks, but some options are safer than others. Here’s an overview based on current research.

Lead Leaching:

Dangerous

Lead is an established neurotoxin and dangerous to human health; prolonged exposure can lead to cognitive decay. According to the Environmental Protection Agency, no level of lead is safe for consumption.

Lead leaching occurs as pipes age, shedding metal flakes from the pipe wall and contaminating the water passing through. While the recommended parts-per-billion (ppb) for lead is zero, the federal government allows up to 15 ppb, which means some municipalities may have “allowable” levels of lead contamination.

To mitigate the possibility of lead consumption, decision makers should take action by testing their water for lead. If lead is confirmed – even 1 ppb – the pipes should be immediately and fully replaced.

Plastic Leaching:

Likely Dangerous

Plastic is manufactured using complex chemical blends, hydrocarbons and other additives. Over time these added substances release (leach) from pipe walls as they age and are degraded by natural forces, such as running water (especially hot water), exposure to sunlight, permeation by chemicals, and other factors.

Chemical leaching from plastic has been well documented. In 2018, a comprehensive study found 163 substances leached from plastic piping, including known human toxins and carcinogens such as benzene, which is regulated at just 5 ppb (three times worse than lead). Possibly more concerning, 74 of the leached substances are not currently regulated, meaning the effect on human health is unknown.

If plastic pipes are used to transport potable water, it is wise to replace them immediately. Plastics are manufactured with substances that increase the pipe’s resistance to wear and tear. In just a few years, these agents can dissipate, exposing chemical components to transported water.

Copper Leaching:

Safe for Most People

Copper pipes leach traces of copper at levels generally regarded as safe. Moreover, at these low levels, copper is an essential nutrient to maintain blood health and support muscle elasticity; this is especially true for the heart. Other common sources of copper include dark chocolate, shellfish and whole grains.

While too much copper leaching is unhealthy, it is not a concern for individuals unaffected by Wilson’s Disease, which prevents the body from automatically regulating copper. The limit for copper is 1,300 ppb, but average levels in North America range from 20- 75 ppb; much less than what is considered unsafe. Copper piping can safely be used for a variety of installations without fear.