The latest figures from the U.S. Environmental
Protection Agency (EPA) show the use of pesticides for the
non-agricultural sector to be around 213 million pounds. That is
roughly twenty-five percent of all pesticide use in the United
States. Homeowners alone use at least 90 million pounds of
pesticides per year on lawns and gardens. And the trend is
increasing. From 1998 to 2001, home usage of pesticides jumped by 42
percent. These figures are underestimations since they only measure
the actual chemical, not the entire pesticide product formulation,
which typically includes more than one chemical. Suburban lawns and
gardens receive far heavier pesticide applications per acre than
agricultural areas.
Homeowners apply between 3.2 to 9.8 lbs per acre
of pesticides on lawns. On average 2.7 lbs per acre of pesticides
are applied on agricultural land.
A recent 2004
study found that certain types of dogs exposed to pesticide-treated
lawns and gardens increases their risk of bladder cancer by four to
seven times. The study adds to earlier research published by the National Cancer
Institute that found elevated rates of canine malignant lymphoma in
dogs exposed to lawn pesticides such as 2,4-D, which is the most
popular pesticide used by homeowners and the main ingredient found
in “weed and feed” products. The latest EPA assessment of 2,4-D
acknowledges the susceptibility of dogs to poisoning by 2,4-D and
other similarly structured lawn pesticides but does not propose any
label warnings to users. Pets, especially dogs, are highly
susceptible and attracted to slug and snail baits containing a
neurotoxicant, metaldehyde, that at very small doses can cause
tremors, seizure, and death.
Of 30 commonly used pesticides used on lawns
and landscapes, 16 are toxic to birds, 24 are toxic to fish and
other aquatic organisms, 11 are toxic to bees, and 11 have the
potential to disrupt the endocrine (hormonal) system in wildlife and
humans. Lawn and garden pesticides are also deadly to beneficial
insects and soil life vital to a naturally healthy lawn. Most
pesticides are broad spectrum, meaning the chemical kills both
“pests” and harmless or beneficial species. For example, carbaryl,
the sixth most widely used pesticide in the home and garden sector,
is highly toxic to honey bees and especially dangerous because it
can be carried back to the hive and kill newly emerged worker bees.”
Other studies show pesticides reduce earthworm populations and
activity. Pesticides that run off lawns into local waterways can
kill or contaminate fish or other aquatic species that contribute to
ecosystem health and serve as food for other fish. Harmful effects
can occur at concentrations far below those that cause death or
obvious signs of toxicity. For example, salmon are extremely
sensitive to certain types of lawn pesticides (such as diazinon,
carbaryl, and malathion) that can affect their ability to feed and
avoid predators.
Consumer and
professional landscape pesticide use both contribute to levels of
pesticides found in streams and other surface water. According to the U.S.
Geological Survey (USGS), “Information now available from the first
phase of the National Water Quality Assessment (NAWQA) program shows
that pesticides are widespread in streams and groundwater, occurring
in geographic and seasonal patterns that follow land use and related
pesticide use.” Results from the NAWQA Program also indicate that several pesticide
mixtures found in urban area streams approach or exceed water
quality criteria, especially in streams that experience seasonal
periods.” Studies
by the USGS also show 2,4-D to be the herbicide most frequently
detected in streams and shallow ground water throughout the country
from home and garden use.
Each year,
approximately 11,000 tons of inorganic nitrogen and 2,100 tons of
total phosphorus are transported by rivers and streams to Puget
Sound and its adjacent waters in the state of Washington. Nearly 1/3
of the nitrogen and 1/4 of the phosphorus come from fertilizers.
Nutrient runoff is three times higher from urban and agricultural
lands than from forest land. Transport of fertilizers and
pesticides in urban areas is greatly increased by paved surfaces and
storm drains.
Pesticides can
drift thousands of miles in the air from the application area, into
people's homes and bloodstreams, exposing them to pesticides without
their knowledge or consent. Alarming levels of pesticides are
found in the indoor air and dust of people's homes. In a 2003 study,
a majority of the homes sampled contained current, old and newly
banned pesticides in the dust, such as pentachlorophenol (86%), DDT
(65%), chlordane (53%), chlorpyrifos (18%). Many of the pesticides found are
suspected endocrine disruptors that mimic cells and can lead to
several cancers and other problems. In a study of pesticides and
their metabolites in urine, the Centers for Disease Control found
that children ages 6-11 had six metabolites of organophosphate
insecticides, three chlorinated phenols and the herbicide 2,4-D.
Even low levels
of pesticides can be dangerous. According to the American Medical
Association's Council on Scientific Affairs, “Particular uncertainty
exists regarding the long-term health effects of low dose pesticide
exposure…. Considering these data gaps, it is prudent for
homeowners, farmers and workers to limit pesticides exposures to
themselves and others, and to use the least toxic chemical pesticide
or non chemical alternative.”