Nitrate Standard Questioned as Too Strict

EPA scientist says 10 ppm limit does not reflect real-world situations, but change is unlikely

Apr. 18, 2026 at 8:11am

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A bold, abstract painting in muted earth tones depicting sweeping geometric arcs, concentric circles, and precise botanical spirals, visually representing the intricate chemical and biological processes involved in the natural nitrogen cycle.A conceptual illustration of the complex natural forces behind the nitrate cycle, which scientific evidence suggests the current regulatory standard may not accurately reflect.Ostrander Today

Jay Lehr, a senior scientist with Environmental Education Enterprises in Ostrander, Ohio, argues that the longstanding 10 parts per million nitrate standard in drinking water does not accurately reflect real-world conditions. Lehr, who previously worked with the EPA on developing the standard, says the agency has known since the 1970s that the limit is too low, but environmental advocacy groups have blocked efforts to raise it to 20 ppm. While Lehr believes the agriculture industry will have to continue living with the strict standard, new scientific findings could help overcome misconceptions about nitrates and farming's role.

Why it matters

The nitrate standard is a key regulation that impacts agricultural practices, water treatment, and public health. Lehr's perspective challenges the scientific basis for the current limit and suggests the standard may need to be updated to better align with real-world conditions, though making changes to long-established regulations can be politically difficult.

The details

Lehr worked with the EPA in the 1970s on developing the 10 parts per million nitrate standard for drinking water. At one point, the EPA's drinking water advisory committee, which Lehr sat on, convinced the agency to propose raising the limit to 20 ppm. However, environmental advocacy groups opposed the change, and the stricter 10 ppm standard remained in place. Lehr argues the 10 ppm limit does not reflect actual nitrate levels found in the environment and that the EPA has known this since the standard was first established.

  • In the 1940s, nitrates were thought to cause 'blue baby syndrome', a condition where nitrates alter the ability of hemoglobin to carry oxygen.
  • From 1971 to 1978, Lehr served on the EPA's drinking water advisory committee.
  • In the early 1970s, the EPA's drinking water advisory committee, including Lehr, convinced the agency to propose raising the nitrate standard from 10 to 20 parts per million.

The players

Jay Lehr

A senior scientist with Environmental Education Enterprises in Ostrander, Ohio, who previously worked with the EPA on developing the nitrate drinking water standard and served on the EPA's drinking water advisory committee from 1971 to 1978.

Environmental Protection Agency (EPA)

The U.S. federal agency responsible for setting and enforcing environmental regulations, including the 10 parts per million nitrate standard for drinking water.

Environmental advocacy groups

Groups that opposed the EPA's proposal to raise the nitrate standard from 10 to 20 parts per million in the 1970s.

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What they’re saying

“The EPA has known since the early 1970s that the standard is too low.”

— Jay Lehr, Senior Scientist

“Once you develop a standard, it's difficult to loosen up on it.”

— Jay Lehr, Senior Scientist

The takeaway

While the current 10 parts per million nitrate standard for drinking water may not accurately reflect real-world conditions, Lehr acknowledges it is likely to remain in place due to the political difficulty of changing long-established regulations, even when new scientific evidence suggests the standard may be overly strict. Farmers will have to continue practicing good stewardship to comply with the standard.