There is a longstanding joke among journalists here that the term “EPA scientist” belongs in the pantheon of oxymorons at the same level as “military intelligence” and “congressional ethics.”
The truth of that quip was reinforced this month when an expert panel at the National Academy of Sciences found that the chemical perchlorate can be ingested safely by humans at doses more than 20 times higher than those deemed safe by EPA scientists.
The assessment, released by the academy on January 10th, is considered crucial for intelligent and cost-efficient regulation of perchlorate, a prime ingredient from rocket fuel that has seeped into drinking water supplies affecting 11-million people in 35 states.
Prodded by lobbyists from the environmental community and the plaintiffs’ bar, the EPA began drafting the first national standards for perchlorate in 1998. In 2002, its scientists concluded that perchlorate levels in drinking water should be no higher than 1 part per billion.
Following in the EPA’s wake, the states of Massachusetts and California have begun work on drafting regulations to mandate safe levels of perchlorate in drinking water. Massachusetts has joined the EPA in suggesting a safe level of 1 part per billion, while California initially is considering a three parts per billion requirement.
Those extremely low levels would force municipalities, the Department of Defense, military contractors and tens of thousands of other manufacturers to spend billions of dollars leaching perchlorate from aquifers and industrial sites.
Almost everyone involved in the massive cleanup protested that perchlorate poses no threat to human health even at levels several hundred times as high as that proposed by the EPA.
To resolve the dispute, the National Academy of Sciences asked a 15-member panel of experts chosen by its National Research Council to review all of the pertinent scientific literature.
After extensive study, the panel concluded that humans could safely ingest levels as high as 0.0007 milligrams per kilogram of bodyweight—more than 20 times the dose of 0.00003 milligrams per kilogram that EPA scientists had recommended.
“This should protect even the most sensitive populations,” said Richard B. Johnston, Jr., a physician with the University of Colorado’s School of Medicine, who chaired the panel.
The NAS committee said it concluded that perchlorate was far less likely to cause thyroid problems in humans than the EPA had determined because humans are much less susceptible to thyroid disruptions than rats, the subject of earlier studies used by the EPA.
This is not the first time that EPA scientists have been called on the carpet for grossly overstating risks of chemicals that later turned out not only to be safe, but useful.
In the 1970s its scientists wanted to ban sweeteners like cyclamate and saccharin because high doses of them caused cancer in rats.
In 1988, they lent support to an activist attempting to ban the spraying of Alar on apples claiming it presented an “intolerable risk” for cancer in children because high doses produced cancer in rodents. The result: a nationwide panic that forced many apple growers in states like Washington, Michigan and Virginia into bankruptcy.
The EPA continues to push bans for many highly-effective industrial and agricultural chemicals by labeling them as “probable human carcinogens”—often on the basis of just one “rodent-consumption” study.
One of the most far-reaching is chlorine, a critical treatment to ensure safe-drinking water which is under attack by eco-activists because large doses can cause cancer in mice.
Perchlorate itself is a mixture of one part chlorine and four parts oxygen. While it occurs naturally in certain areas of Chile and Texas, it also has been used in fertilizers for decades so trace amounts can show up in milk and produce as well as water.
The National Academy of Sciences review of perchlorate comes at a time when scientists at prestigious universities such as Yale, Stanford, Michigan State and Harvard are raising the questions about the validity of using high-dose animal tests to predict human cancer risks.
Elizabeth Whelan, president of the American Council on Science and Health, points out that animal carcinogens abound both in nature and in man-made products. And she notes that if the rat-to-human extrapolation were applied to natural, organic foods, “we would have nothing left to eat.”
Congress can remedy this situation by rescinding outdated laws like the 1958 Delaney Clause that requires the U.S. Food and Drug Administration to ban food additives causing cancer at any dose in any lab animal no matter how negligible the risk. It’s clear that the physical health of the American people won’t be jeopardized by realistic standards that are based on studies involving humans rather than rats. It’s equally clear, that overly stringent standards will jeopardize the economic health of all Americans.
In the meantime, regulators at the EPA and their counterparts in California and Massachusetts ought to follow the guidance of the National Academy of Sciences’ blue-ribbon panel in setting standards for perchlorate. Common sense should be the order of the day.
