DDT: The 50th Anniversary Everyone Forgot

Photo: Michigan State University ornithologist George Wallace

By Dave Dempsey

Engulfed in a mammoth chemical crisis involving a family of chemicals known as PFAS, Michigan has something to learn from a 50th anniversary that passed unnoticed last month.  In April 1969, Michigan became the first state to effectively ban DDT.

It wasn’t easy or quick.  Michigan State University ornithologist George Wallace found as early as the 1950s that mass die-offs of robins on campus were directly attributable to DDT application — research that Rachel Carson cited in her 1962 classic Silent Spring.  Most state and federal officials, however, and the all-powerful farm lobby, opposed tough action on the pesticide.  But gradually, things began to change.

Michigan Department of Natural Resources Director Ralph MacMullan became a leader in the fight to ban the so-called “hard pesticides.”  Defying the state Agriculture Department and Governor George Romney, he campaigned for bans on DDT, dieldrin, and other bioaccumulative chemicals.

“The effects of this storing-up of pesticides in animals,” MacMullan wrote, “from the smallest to largest is not completely known, but gaps are beginning to be filled in. Man, for the first time in his history, has chemicals at his disposal that can completely alter his own food chain.  By wiping out certain insects or minute sea-creatures he removes link after link in the very delicately balanced chain of life on which he depends… [T]here is enough evidence for us to be greatly concerned and to start bringing the unnecessary and widespread use of these persistent chemicals to a halt.”  Fears of harm to human health, as well as fish and wildlife, from DDT exposure mounted.

In the late winter and early spring of 1969, government agencies found alarmingly high levels of DDT in coho salmon, which in just three years had become the centerpiece of Michigan’s lucrative sportfishery. In February 1969, the Michigan Department of Agriculture – which had regulatory responsibility over commercial food sales as well as control of pesticides application – tested Lake Michigan salmon captured by a Grand Rapids packing company at weirs on spawning streams.  The company had pulled two million pounds of fish from the state’s waters in the fall of 1968 for dressing, canning, or storage in freezers. To its dismay, MDA found relatively high levels of dieldrin in the salmon and embargoed from sale 500,000 pounds of fish.

Soon after, the U.S. Food and Drug Administration examined interstate shipments of coho, found high levels of DDT, and seized 14 tons of fish. Federal agencies moved to set a “tolerance” level – a limit on the amount of DDT residue permitted in fish sold in interstate commerce – of 3.5 parts per million. Only Lake Michigan smelt might pass inspection under that level, said Dr. Wayne Tody, the DNR’s fish chief. Now more was at stake than the elusive matter of ecosystem integrity.  Two industries, commercial fishing and sportfishing-based tourism, were at risk from the use of pesticides to protect another, agriculture. “End of Sports Fishing Near?” asked a headline in the April 10, 1969, Lansing State Journal.

Since 1962, the Michigan State University Agricultural Experiment Station had already eliminated DDT from many of its recommendations for insect control, and recommended reduced dosages in the remaining instances.  In February 1969, under Dr. Gordon Guyer, the Station decided to eliminate DDT from its recommendations altogether. This would have the effect of phasing out, over time, the use of DDT by Michigan farmers.

Notified of this decision and worried about losing his pesticide control authority if left alone defending DDT, Michigan Department of Agriculture Director B. Dale Ball chose a more aggressive route: he proposed cancellation of DDT registrations for all but three minor uses, to take effect within 60 days.  The Commission of Agriculture agreed with the proposal in April 1969, thus making Michigan the first state to cancel most uses of DDT.  MacMullan cheered the action.

The state’s current struggle with PFAS is analogous in only one way — in the aggressiveness, or lack of same, with which our state agencies tackle the problem.  DDT is a particular chemical, while PFAS are a family of thousands. Yet the basic issue persists — will Michigan wait for the feds, or exercise its own powers as a guardian of the Great Lakes as well as its 10 million people?

There are good signs in both the aggressive public drinking water supply testing program that began under former Governor Rick Snyder and the directive by Governor Gretchen Whitmer  for development of a drinking water standard for PFAS (there is no federal standard).  Both of these actions put Michigan in the vanguard of states grappling with PFAS.

But it’s only the beginning.  The state must develop plans for handling and disposal of stocks of the key PFAS chemicals, address the health concerns of citizens exposed to PFAS in their drinking water or through direct contact, and coerce polluters into paying for necessary cleanup, among other things.