Integrated Pest Management
PROBLEM: Conventional Pesticides
Decades after DDT was banned in the United States and most of the world, it’s still being detected in penguins in Antarctica, thousands of miles from where it was used.1 Do you think the pesticides you spray in your garden are somehow staying out of your homes? Anything you spray to kill bugs or weeds in your garden is also being brought in to your home. Concentrations of pesticides in dust indoors is higher than it is in the soil outside, even on farms.2
It is understandable to feel overwhelmed by the number of pests in your home and garden. If you have a particularly nasty infestation, it may seem like the only solution is massive amounts of bug spray, or better yet, a “bomb” that will fill your house with a cloud of insect-killer. And it’s true that after using these methods you will likely find dozens of dead organisms littering your property. When it comes to weeds, you may be tempted to buy a solution in a bottle instead of getting down on your hands and knees to pull them from the ground. But these chemicals can be harmful in ways we cannot always predict.
When DDT was first used, it was considered a “miracle” pesticide. It wiped out virtually every organism that harmed crops. However, it was later discovered that DDT (and its relatives DDE and DDD, which are what DDT can break down into in the environment) did not just disappear after it killed unwanted insects. This pesticide is particularly persistent in the environment, and is retained in the soil. When the pesticide is washed downstream and into rivers and lakes, it accumulates in the bodies of fish, which are eaten by birds such as the Brown Pelican, Peregrine Falcon, and Bald Eagle. When one ton of contaminated fishes are turned into 200 pounds of seabirds, none of the toxins are lost, they are only more concentrated—this is called bioconcentration.3 When these birds are exposed to high levels of DDT in their diet, they don’t die outright. Instead, they lay eggs with such thin shells that the offspring don’t have a chance to fully develop before the eggs fall apart.
Though DDT has been banned in most parts of the world, its effects demonstrate the danger of using toxins to kill every possible pest without giving a second thought to the possible repercussions. If you are spraying pesticides, inside or out, you are going to end up breathing in the same toxins that you’re using to kill other organisms.
The EPA has found that pyrethroids, some of the more popular synthetic insecticides on the market today, may impact the immune systems of children4 and may be neurotoxic during development.5 Is your garden worth the risk?
In the 1940s, farmers in the United States lost seven percent of their crops to pests; since the 1980s, they’ve lost 13 percent, despite the fact that they’re using more pesticides than ever.6 This is because people using pesticides are unintentionally creating pressure on pests that results in artificial selections; the only pests that survive spraying are the ones with a mutation that keeps them alive, and the next generation will be largely composed of these resistant pests.
So if pesticides and herbicides are potentially dangerous, and in the long run ineffective, what is the alternative?
1 “Antarctic Melt Releasing DDT, Tainting Penguins,” National Geographic News, May 12, 2008, http://news.nationalgeographic.com/news/2008/05/080512-penguins-ddt.html (accessed December 13, 2010).
2 R. Lewis et al., “Measuring and Reducing Exposure to the Pollutants in House Dust,” American Journal of Public Health 85 (1995).
3 Paul R. Ehrlich, David S. Dobkin, and Darryl Wheye, “DDT and Birds,” http://www.stanford.edu/group/stanfordbirds/text/essays/DDT_and_Birds.html (accessed December 13, 2010).
4 “Permethrin & Resmethrin (Pyrethroids),” The Environmental Protection Agency, (2007), www.epa.gov/teach/chem_summ/pyrethroids_summary.pdf
5 Timothy J. Shafer, Douglas A. Meyer, Kevin M. Crofton, “Developmental Neurotoxicity of Pyrethroid Insecticides: Critical Review and Future Research Needs,” Environmental Health Perspectives 113, no. 2, (2005), http://ehp03.niehs.nih.gov/article/fetchArticle.action?articleURI=info:doi/10.1289/ehp.7254 (accessed December 13, 2010).