DDT was a pesticide that essentially changed the way people lived in the postwar era. The Swiss chemist who first synthesized the chemical even won a Nobel Prize for its effectiveness in beating back not only insect parasites – but also most of the diseases they carried, like malaria and typhus. But it became the focus of intense scrutiny by the nascent environmental movement, and was banned in the U.S. in 1972.

But a new form of the DDT crystal is not only more effective – it is also significantly safer, according to a New York University chemistry investigation.

The newly discovered crystalline form is more effective – and means using much less of it, the chemists report in the journal Angewandte Chemie.

“The finding is a surprising one as, for decades, DDT crystals were though to exist in only one form," said Michael Ward, one of the authors. “This new knowledge opens the door to future development of a more effective produce that could diminish the dangers posed by existing forms.”

The scientists identified the new way to make the crystals by observing the formation of the known cr5ystal forms – and then tweaking that method.

The efficacy of the two crystals were tested on fruit flies. (DDT is sprayed, and the solution forms crystals which are deadly when touched by the insects, either by walking or landing on it). The new crystal form was found to be more effective at smaller amounts, they report.

“The possibility that one crystalline form may be more active than another provides an opportunity to optimize pesticide formulations with a reduced amount of compound applied, achieving the necessary protection, whether against disease or infestation, while minimizing environmental impact,” said Ward.

The authors also penned an accompanying essay in the journal which highlights the dangers of DDT. It also defends the legacy of Rachel Carson and her book Silent Spring, the 1962 book that is popularly credited with launching the environmental movement. Carson and her work are misrepresented by opponents who use a “false DDT narrative to oppose any and all environmental regulation,” they contend.

“Make no mistake: DDT in its known state has been proven time and again to be damaging to our environment, most notably wildelife,” said Bart Kahr, the senior author.

Silent Spring blamed many wide-ranging environmental problems on DDT and related pesticides. In fact, the populations of predatory birds such as the bald eagle and the peregrine falcon have rebounded since DDT use was discontinued. However, the extent of toxicity in humans retains some level of controversy even today.