The Effect of Pesticides on the Environment
Whenever the subject of pesticides comes up, it's easy to point a finger at farmers. But we homeowners, with our manicured lawns and exotic flower gardens, have nothing to be smug about. Each year we pour approximately 136 million pounds of pesticides on our homes, lawns, and gardens, which amounts to three times more per acre than the average farmer applies. In fact, most of the wildlife pesticide poisonings reported to the U.S. Environmental Protection Agency result from home use. According to the EPA's wildlife mortality incident database, just three of the chemicals commonly used in the garden and home--diazinon, chlorpyrifos, and brodifacoum--kill thousands of birds each year.
In the early 1990s two California metropolitan areas--the City of Davis and central Contra Costa County--discovered levels of diazinon and chlorpyrifos, high enough to harm aquatic organisms, in their storm-water systems. After testing, officials in both places determined that the greatest source of pesticides in local surface waters was single-family homes.
"Chlorpyrifos is very prevalent," says Jacques DeBra, pollution prevention program manager with the City of Davis Public Works Department. "It's like mowing the lawn. People have been using it for years. It's hard to get them to look at alternatives."
Oddly enough, both diazinon and chlorpyrifos (see chart, below), because of their high toxicity to birds and wildlife, meet the Environmental Protection Agency's criteria for "restricted use," which means that they require a permit and training to purchase. The Rachel Carson Council petitioned the EPA to upgrade the label for diazinon in 1997 and last year requested that the use of chlorpyrifos be banned around dwellings.
When and where pesticides are used is also critical. The majority of bird kills occur in February in southern states, where the...