A Little Less Green?

Studies challenge the benign image of pyrethroid insecticides

Rachel Carson turned the pest-control world upside down in 1962. In Silent Spring (Mariner), she documented how long-lived organochlorine pesticides, most notoriously DDT, were not only ridding croplands of insects, streets of mosquitoes, and homes of spiders but also exacting a high toll on songbirds and other nontargeted species. The chemicals’ broad-spectrum potency and resistance to breakdown, advantages in their use against pests, emerged as hazards.