The term pesticide is inclusive of insecticides, herbicides, fungicides, fumigants, algaecides, aviacides, and rodenticides. Pesticides target about 2,000 different pests (specific bugs, weeds, molds, birds, rodents, etc.). However they can affect as many as 200,000 non-target species including people. It is important to understand how these chemicals affect our ecosystems.
ECOTOXICOLOGY
Ecotoxicology is the study of how chemicals impact on the environment. The ECOTOX (ECOTOXicology) database provides single chemical toxicity information for aquatic and terrestrial life. When evaluating the effects of pesticides in the environment, the following must be considered:
- Toxicity (What is its effect on an organism, i.e. does it affect respiration, is it a neurotoxin, does it lead to cancer?
- Volatility (Is it readily vaporized and difficult to handle?)
- Effect on non-target species (Are beneficial insects also killed and how does that affect the balance of species in an eco-system?)
- Persistence in the environment (How long does it take to breakdown and become harmless?)
- Chemical breakdown (What happens when the chemical breaks down? Does it form toxins?)
- Motility in the environment (Is the chemical dispersed into ground water and rainwater as with Atrazine?)
- Fat solubility (Is it absorbed and stored in the fat of animals, thereby entering the food chain as in the case of DDT)
- Synergy (How does the chemical interact with the environment to create new toxins? There is very little research on the health effects of the ‘chemical soup’ created by all the chemicals human activity create.)
Other environmental hazards associated with pesticide use may include:
- Worker exposure during production
- The possibility of industrial accidents (e.g. Seveso, Bhopal, Basle)
- The possibility of transportation accidents (e.g. the loss of containers holding a seed treatment substance in the North Sea)
- Incorrect use in the field
- Improper storage and disposal of unused chemicals and packaging
PESTICIDE CLASSES (Back to Top)
Classes of Insecticides
- Oils are petroleum products that are used to coat either water or soil or plants to prevent insect emergence.
- Inorganics have restricted use because of their toxicity to humans and persistence in the environment. They include lead arsenic, sulfur derivatives, paris green, and calcium arsenate.
- Botanicals are derived from plant material. They are safer than petrochemicals for the environment because they break down into harmless compounds within days. However, some are very toxic to humans, birds, fish, or plants at the time they are sprayed and they are not selective because they kill any insect that eats them.
- Synthetics or Organics are used mostly today and can be classified as follows:
- Carbamates which are relatively new and break down to less toxic chemicals and do not accumulate in fat. They include Furadan, Lunnate, and Sevin.
- Organophosphates which are mainly contact pesticides, although some are absorbed by respiration. They act as nerve agents and in higher animals cause nausea, salivation, muscle spasm, coma, convulsions. They include Azodrin, Parathion, Malathion.
- Organochlorides (chlorinated hydrocarbons) are fat soluble, persistent, mobile, and very stable. The central nervous system is the main target, causing hyperactivity and convulsions. They include DDT, dieldrin, aldrin. Another organochlorine is polycholrinated biphenyls or PCBs. PCBs pose serious health problems.
- Biological methods utilize organisms to control pests. These include the introduction of other organisms such as lady beetles, ‘beneficial nematodes’ or praying mantis. Even this natural method can also have unwanted consequences. When parasitic flies were introduced to control gypsy moth infestations (an accidentally introduced pest), at first it was hailed as a successful control measure, but years later it was discovered that the flies had done more damage to non-target species.
Classes of Herbicides (Back to Top)
- Inorganics include arsenic, copper, and sulfur compounds.
- Organics include: contact herbicides such as Atrazine, simazine, and pentachlorophenol.
- Systemic herbicides such as 2,4-D and 4,5-T and silvex. Substituted ureas such as fenuron, diuron, and nurea, are a group of systemic herbicides that are water soluble so as to be quickly absorbed by roots, accumulating in leaves to inhibit photosynthesis.
- Soil sterilants such as Treflan, Dymid, Aatrex, Dowpon, and Sutan.
There are approximately 875 registered pesticide active ingredients. The number of common pesticide degradation products is unknown. Only a few pesticide parent compounds and degradation products are routinely tested for. (Analytical methods to detect pesticide degradates are either difficult, expensive, or unavailable.)
References for the above information include:
Anderson, Beiswenger, Purdom. Environmental Science [3d Ed.], Merrill Publishing Co., Columbus,
1987.
Rombke and Moltmann. Applied Ecotoxicology. CRC Press, 1996,
Rodale’s Chemical–FreeYard & Garden. Rodale Press, 1991.
Pesticide Resistance (Back to Top)
Pesticide resistance - both herbicide and insecticide resistance is a growing problem. "Today, pests that were once major threats to human health and agriculture but that were brought under control by pesticides are on the rebound. Mosquitoes that are capable of transmitting malaria are now resistant to virtually all pesticides used against them. This problem is compounded because the organisms that cause malaria have also become resistant to drugs used to treat the disease in humans." (R.G. Bellinger, PhD, Clemson University, Pest Resistance to Pesticides, pdf) Pesticide resistance poses a significant threat to the food industries and public health. Croplife International (representing companies like BASF, Bayer CropScience, Dow Agrosciences, DuPont, FMC, Monsanto, Sumitomo and Syngenta, etc) has formed several international groups to contain the problem including the Insecticide Resistance Action Committee, the Herbicide Resistance Action Committee the Fungicide Resistance Action Committee. The Herbicide Resistance Action Committee (HRAC), the North American Herbicide Resistance Action Committee (NAHRAC), and the Weed Science Society of America (WSSA) post Weed Science a database monitoring the evolution of herbicide-resistant weeds. ON Nov. 06, 2005 they listed "304 Resistant Biotypes, 182 Species (109 dicots and 73 monocots) and over 270,000 fields." Pesticide Resistance Management at Michigan State University - U. Michigan's database currently lists 540 pesticide resistant arthropods - mites, mosquitoes, leafrollers, etc. (Nov. 2005). 171 resistant species have been recorded in Canada, such as DDT resistant mosquitoes and diazinon resistant leafrollers. Multiple resistances are found in many insects including maggots, beetles and mites. These are serious findings.
The solution to pesticide resistance is multifold. First and foremost, a reduction in the general usage of pesticides is mandatory. They are overused and used incorrectly. Pesticides use should be limited to critical situations. The same pesticide should not be used in subsequent treatments, rather a rotation of chemicals can help to limit the evolution or resistance. Good agricultural practice including such things as crop rotation should help to limit pest problems. Organic farmers are able to eliminate all synthetic pesticides. Pesticides for cosmetic purposes, e.g. lawn care, should be stopped.
Pesticides and Lawn Care (Back to Top)
The cosmetic use of pesticides poses unnecessary risks to public health and the environment. In addition, overuse of pesticides is upsetting soil ecology, creating weed and pest resistance while at the same time wasting resources. Many communities have banned cosmetic use of pesticides.
In July of 2001, the Supreme Court upheld a decision to permit communities to ban pesticide use on lawns. Presented with the evidence from the Ontario College of Family Physicians, the Canadian Public Health Association and the Learning Disabilities Association of Canada who concurred that "pesticides affect neurological development, reproduction, growth, and the functioning of the immune and endocrine systems" along with information from the U.S. National Cancer Institute survey which found "that children with leukemia are six times more likely to come from homes where pesticides were used," the judges saw fit to allow communities to ban pesticide use. Since this decision, numerous communities have done just that.
Unfortunately, in
my
About 200 different pesticides are permitted for lawn
care in the US and Canada. According to Vermont Public Interest Group (VPIRG), "Americans maintain over 25 million acres of lawn, with an average amount of 5 to 10 pounds of pesticide (active ingredient*) used per acre per year. That rate of pesticide use is more than three times as high as rates of pesticide use on farms, and it means that we are exposing ourselves, our children and our environment to the unintended effects of as much as 200 million pounds of pesticides nationwide from lawn care alone"
(
Healthy Lawn Care for Healthy Communities). The figures for
Canada are not readily known. Excessive pesticides use for the maintenance
of a uniform green groundcover is having unfortunate consequences.
Pesticides,
after all, are poisons. Pesticide use has been shown to cause cancers,
neurological disorders and endocrine disruption. One needs only to
scan the
Environment and Human Health Inc. (EHHI) have put together a thorough report entitled Risks from Lawn Care Pesticides. "Some chemicals commonly used on lawns and gardens have been associated with birth defects, mutations, adverse reproductive effects, and cancer in laboratory animals. Children, infants, and fetuses may be especially vulnerable to the health effects of pesticides before the age of five, when their cells are normally reproducing most rapidly." EHHI provide well documented information and recommendations for change. In April 2004, the Ontario College of Family Physicians released a comprehensive review of the health risks from pesticides. Become informed read a Sample of Recent Studies of Health Impacts of Pesticides from the Minnesota Center for Environmental Advocacy.
There is no question that pesticide use has caused and is continuing to cause environmental damage. Since the ravages of DDT, no one is mindless of the potential to do harm. Yet many are unaware that overuse of pesticides is leading to the development of pesticide resistant species - just as overuse of antibiotics has contributed to the evolution of disease-causing organisms resistant to drug therapy. "In less than a generation, resistance has grown exponentially. Weed resistance now includes over 163 species. Today there are 504 resistant insect species, 272 resistant weed biotypes, 163 weed species (98 broadleaf and 65 grassy) 150 resistant fungi in 59 countries,"(Canola Council http://www.canolacouncil.org/pestresistance.aspx). Pesticides are important chemicals needed to combat serious infestations. If we continue to allow casual use of pesticides, our agricultural industry will suffer and our ability to combat serious problems will be diminished.
It
is hard to say to the public, you shouldn’t use these products for
cosmetic purposes. After all, a lush green uniform lawn has become something
of a status symbol. Heedless of the environmental costs associated
with pesticide use, (including the fact that pesticides are energy
intensive to produce and come predominantly from the cracking of crude
petroleum oils or from natural gas), most homeowners just want a pretty
product. They are unaware of their particular soil composition and are
unaware of the millions of extraordinary creatures living in their yards.
Unknowing, they buy a bag of Weed
and Feed or hire a company and regularly distribute fertilizers
and pesticides. Most people are ill-equipped to recognize that
their actions can actually increase pest outbreaks by upsetting
the complex web of life beneath their feet. For six years now,
I have refrained from pesticide use. My beautiful lawn and garden have won
awards and my yard is rich with life. A pretty product is very obtainable
without pesticide use.
We have become far too comfortable with casting granules of poisons at our feet simply to create a uniform green groundcover. Pesticides are important chemicals and this is not an appropriate use of them. Responsible government should act to protect the public and the environment as a whole from harm caused by the needless cosmetic use of pesticides.
May 21, 2003, Toronto city banned the cosmetic use of pesticides for lawn care. They join numerous Canadian municipalities and the province on Quebec in restricting the use of pesticides. Please work to support a pesticide bylaw in your community.
Environment Canada posts 12 Easy steps to... Get Your Lawn Off Drugs. You will find sites abounding on the web to help you reduce pesticide usage. The Pesticide Free Ontario is one of many groups providing action kits to help communities reduce pesticide usage.
Catherine Kavassalis - Nov. 2005
Links of Interest: (Back to Top)
- Health Canada Pesticide Management Regulatory Agency
- PMRA is the federal agency responsible for the regulation of pest control products in Canada. As the federal authority under the Pest Control Products Act (PCPA). See Factsheet of pesticide regulation.
- Managing the Safety of Pesticides in Canada
- This is a 2003 report from the Commissioner of the Environment and Sustainable Development. "Overall, we conclude that the federal government is not managing pesticides effectively. We found weaknesses in many areas, such as re-evaluations, and we noted that problems in some areas spilled over into other activities. For example, gaps in monitoring mean that re-evaluations depend on incomplete, inconsistent, and out-of-date information."
- EPA - Chemicals Evaluated for Carcinogenic Potential (2002)
- The EPA has compiled data on carcinogenic potential for an extensive list of chemicals including pesticides and herbicides.
- EPA - ECOTOX
- The ECOTOXicology database (ECOTOX) is a source for locating single chemical toxicity data for aquatic life, terrestrial plants and wildlife.
- EPA Office of Pesticide Programs
- This branch of the EPA was created to "protect public health and the environment from the risks posed by pesticides and to promote safer means of pest control." Endangered Species Protection Program was created to protect endangered species from harmful pesticides.
- EPA Integrated Risk Information System (IRIS)
- This is a database of information on human health effects that may result from exposure to various chemicals in the environment, for use in risk assessments, decision-making, and regulatory activities.
- Federal Insecticide, Fungicide and Rodenticide Act (FIFRA)
- FIFRA provides for federal control of pesticide distribution, sale, and use. In addition, under FIFRA, EPA can suspend or restrict the use of certain pesticides if an endangered species will be adversely affected.
- USDA Agricultural Chemical Usage
- The USDA's National Agriculture Statistics Service provides chemical application rates and acres treated by major producing states and US for field crops annually (corn, soybeans, cotton, potatoes, wheat); selected fruit crops and selected vegetable crops are reported in alternate years.
- USGS National Water Quality Assessment Project (NAWQAP)
- NAWQAP's Pesticide Synthesis Project has released numerous publications including: Pesticides in Ground Water (and Pesticides in Ground Water for kids); Pesticides in the Atmosphere; Pesticides in Surface Water, etc.
- USGS Midcontinent Herbicide Project
- The USGS has begun to study the affect of herbicides on the soil and water in the mid United States. They hope to provide information that will lead to the improvement of agricultural practices and protect water systems.
- USGS Contaminant Exposure and Effects - Terrestial Vertebrates Database
- The Biomonitoring of Environmental Status and Trends (BEST) program is designed to assess and monitor the effects of environmental contaminants on terrestrial vertebrates on the Atlantic Coast. Currently, the CEE-TV database contains approximately 4,000 records containing ecotoxicological exposure and effects information on over 150,000 individuals representing 200 species of amphibians, reptiles, birds, and mammals residing in estuaries.
Pesticide Free
Organization providing information and action
- EXtension TOXicology NETwork
- This site supplies pesticide toxicology and environmental chemistry information for the general public - fully searchable and selectively retrievable.
- Spectrum Laboratories Compound Database
- This site is under construction but includes technical data sheets on various compounds, including pesticides like Atrazine.
- Pesticide Action Network
- PANNA (Pesticide Action Network North America) works to replace pesticide use with ecologically sound and socially just alternatives. This is one of five PAN Regional Centers worldwide, PAN UK is also excellent. They have developed an extensive pesticide database.
- Pesticides and Birds Campaign
- This organization is working to reduce the number of pesticide related bird kills. This site provides information from EPA and Fish and Wildlife Services on die-offs related to pesticides.
- Beyond Pesticides
- Beyond Pesticides began in 1981 as the National Coalition Against the Misuse of Pesticides, a non-profit membership organization that was formed to serve as a national network committed to pesticide safety and the adoption of alternative pest management strategies which reduce or eliminate a dependency on toxic chemicals.
- Northwest Coalition for Alternatives to Pesticides
- Promotes sustainable resource management, prevention of pest problems, use of alternatives to pesticides, and the right to be free from pesticide exposure.
Misc.
- Pesticide.net
- Pesticide related news compiled by the law firm of Wright & Sielaty and scientific and regulatory consultants at ChemReg Int'l. They list only briefs online and there is a subscription fee for full text access.
- Information on Pesticides and Other Chemicals
- Cornell University's Breast Cancer Research Center has developed an excellent database for pesticide research - particularly as it relates to cancer.
- A Problem with Fertilizer Industry in Indiana
- This article from the Indianapolis Star 24aug01 reported on a state investigation of fertilizer storage and handling sites. "Problems varying from missing contingency plans to spills of chemicals that might be polluting waterways, raises questions about how safely fertilizer and pesticides are handled at such facility."
- Effects of the Herbicide Atrazine on Tiger Salamanders
- This is a USGS supported research paper explaining the negative effects of atrazine on this species.
- Atrazine in Lake Michigan
- This is a brief page created by the Lake Michigan Federation concerned about the use of Atrazine and the contamination of land and water in the Lake Michigan area. They are awaiting a full reporting for the EPAs Lake Michigan Mass Balance Project .
- Background Information on Cyanazine
- In 1992, the EPA announced a voluntary phase out of cyanazine. "Cyanazine is essentially atrazine with cyanide attached to it." This information sheet was produced in 1995 by the Environmental Working Group.
| West Nile Virus and Mosquito Spaying
(Back to Top) The CDC provides a wide variety of information about the West Nile Virus. Only 1% of people bitten by an infection-carrying mosquito (which is again a small fraction of the mosquito population) will experience serious effects. Adults over 50 with compromised immune systems are the most likely to be adversely affected. Such individuals should take extra precautions to reduce exposure. Most others are not likely to be made seriously ill by being bitten. (See 2001 pdf: Epidemic/Epizootic West Nile Virus in the United States: Guidelines for Surveillance, Prevention, and Control). To put things in perspective, look at the Canada's CBC report on West Nile. Particularly their statistics page on Causes of Death. The Center for Disease Control and Prevention currently reports 277 deaths due to West Nile for 2002 in the U.S., (see CDC WN Case Count). In 2000, nearly 20,000 Americans died of drug-induced causes and another 20,000 died of alcohol-induced causes. 5,430 Americans died from injuries suffered while at work and 28,663 people died from firearms. 14,478 people died from HIV/AIDS, (see CDC's Mortality Data). These figures are presented to provide perspective. Concern over West Nile is warranted and precautions should be taken, but panic should not drive the reckless use of pesticides. If you are concerned about the disease, take appropriate avoidance measures, e.g. don't spend time outdoors when mosquitoes are most active, wear protective clothing, etc. "In the United States, as of November, 2002, the Centers for Disease Control and Prevention reported that children under age 9 made up only about 1 per cent of the 2,354 cases in which there was any kind of serious infection. None of the 201 people who had died in the United States was younger than 24. All of which leads to the argument that it could be better to be infected early with a mild case of the illness; especially if that protection will last you for life. It is a way of thinking, point out experts, that often prevailed before vaccines were available. At measles or mumps "parties," parents tried to expose their children to these illnesses." (May 12, West Nile's threat to children debated, Toronto Globe and Mail). Food for thought. The USGS site Managing West Nile, Harvard School of Public Health's, Mosquito Born Viruses pages and Cornell's West Nile information page are particularly good for more in-depth information. Note that "One vaccine has been conditionally licensed by the USDA-APHIS's Center for Veterinary Biologics (USDA conditional licensed 8/101) for use in horses in the USA." Work on vaccinations for at risk humans is underway. Local monitoring is important. Managing local mosquito populations may help to reduce the risk of exposure. According to the CDC, "The most effective and economical way to control mosquitoes is by larval source reduction. ...Control of adult mosquito populations by aerial application of insecticides is usually reserved as a last resort." If mosquitoes carrying the virus are detected, larval control can be initiated along with public education. (See Larval Habitats of Mosquitoes) For information on mosquito repellents see the June 1st article in the Annals of Internal Medicine, Mosquitoes and Mosquito Repellents: A Clinician's Guide. Healthy wetlands provide habitat for many natural enemies of mosquitoes. These natural predators keep the mosquito population low. The Indiana Department of Natural Resources advocates wetland restoration to decrease mosquito populations. Natural wetlands provide habitat for the natural enemies of mosquitoes and prevent or reduce flooding, which can provide breeding areas for mosquitoes. Learn more from IDNRs HEALTHY WETLANDS DEVOUR MOSQUITOES. Purdue also has prepared a pdf file called Management of Ponds, Wetlands, and Other Water Reservoirs to Minimize Mosquitoes WQ-41-W and from the US Fish and Wildlife Service: WETLANDS RESTORATION AND MOSQUITO CONTROL. ANVIL is the trademarked name for one of the more common pesticides being used to confront mosquito populations. This compound contains 10% sumithrin (a synthetic pyrethroid) 10% piperonyl butoxide and 80% inert ingredients (including polyethylene benzene PEB). (See also New York State Anvil Information Sheet for information about safety and usage.) Although this pesticide is safer than some, it is still a poison which should be used with due consideration. Whether the local risk of contracting West Nile Virus outweighs the risk of exposure to these substances is subject to debate. NY City NoSpray Coalition is one group actively opposing the spraying of Anvil. They have filed suit against the city of New York citing violations of the Clean Water Act, the Conservation and Recovery Act along with other state and local environmental protection laws in association with spraying. In their suit they claim spraying was not preceded by 48 hours of public notice and that, "two deaths were associated with exposure to pyrethroids in that time period, as well as 15 major health cases" and that spraying came within 100 feet of waterways. (See brief ) The EPA provides a datasheet on synthetic pyrethroids. Pyrethroids and piperonyl butoxide are listed in the Hazardous Substances Data Bank as Chemicals Associated with Asthma and both are likely to be have genotoxic effects - carcinogens, (See EPA documents 1 and 2 and 3). If spraying is to occur it must be done so safely - away from people and bodies of water (the EPA prohibits the direct application of products containing pyrethroids to open water or within 100 feet of lakes as it is highly toxic to fish and aquatic life). Proper notification of where and when applications are to occur is critical. Those applying the product should take great care. If spraying has occurred near you wash exposed skin, toys, furniture etc. Restrict children from playing in sprayed areas. Draft Press Release to notify public about spraying. West
Nile virus, fragmentation and the brown-headed cowbird |
-----------------
Site Under Construction
Site developed by Catherine Kavassalis <c.kavassalis@gmail.com>
Site hosted by Evul networks
Last modified December 11, 2005 . Site Stats