Pesticides -- Good for Your Health? Part 2

June 30, 2002

By Michael Jessen

Pesticides were first used more than 3,000 years ago, but the modern agri-chemical industry was born during World Wars I and II. Chemicals and technologies developed to kill during warfare were later concentrated on the farm to destroy pests and weeds. Chemical weapons found new killing fields.

Ancient Romans used sulphur as a fumigant and common salt to control unwanted vegetation. The Chinese later used arsenic to control garden pests. The first synthetic pesticide -- potassium dinitro-2-cresylate -- was marketed in Germany in 1892. Crop dusting on cotton began after World War I. German scientists experimenting with nerve gas during World War II synthesized the organophosphorous insecticide Parathion. It was marketed in 1943 and is still widely used today. During the 1950s and 60s the use of organophosphate and carbamate insecticides mushroomed and became a major industry. Today more pesticides are used in more countries than ever before and approximately 80 percent of the world's pesticide production is controlled by only 20 companies. Annual sales total more than $26 billion.

The connection between pesticide development and warfare should give humans a clue to their danger. Pesticides are toxic and poisonous yet they are deliberately spread over large areas. Pesticides include insecticides that kill insects, herbicides to kill plants, fungicides to kill funguses, and rodenticides to kill rodents. Why should it be a surprise that chemicals developed to strike dead targeted species might also harm and kill unintended creatures?

Some farmers and all the pesticide manufacturers tell us these chemicals are needed to provide our food. Crop production and yield would fall by 40 percent they proclaim. But living with chemicals has become a risk to human beings. Pesticide regulation is all about balancing this risk with their economic benefit. All too often, chemicals will stay in use because government decides that the economic benefit outweighs the human health risk. While eating should be a "no risk" activity, pesticide use has forced us to balance the need to protect public health with the need to provide the public with an adequate food supply.

As evidence of the effects of pesticide use on human health mounts, a growing number of scientists, doctors, legislators, and even communities are calling for a halt to pesticide use because the risk is unacceptable. What follows is just some of the documentation that is damning our continued use of dangerous pesticides.

 Learning disabilities and certain cancers are on the increase in children and pesticides and industrial chemicals may be to blame says Philip Landrigan, director of the Center for Children's Health and the Environment at the Mount Sinai School of Medicine. His center ran a series of ads in the New York Times earlier this month about the hazards of industrial chemicals, including pesticides. Dr. Landrigan says less than half of the 3,000 chemicals produced in high volume in the U.S. have even minimal toxicity data and fewer than 10 percent have undergone testing to determine if they damage the developing brain of the fetus and reproductive organs. In addition to learning disabilities, Dr. Landrigan alleges steep increases in the rates of leukemia and brain cancer in children are due, at least in part, to certain chemicals. Dr. Landrigan's testimony on June 11, 2001 before the U.S. Senate Committee on Environment and Public Works about the link between cancer and the environment is available at It makes chilling reading.

 The recent World Conference on Breast Cancer held in Victoria heard that rates of breast cancer between 1980 and 2000 have almost doubled around the world, with the U.S., Canada, Great Britain, European countries leading the pack. Helen Lynn of the Women's Environmental Network (WEN) in the United Kingdom told delegates about studies that found more than 170 chemicals lodged in human breast and fat tissue. Some of the chemicals mimic hormones and Lynn said they are at least partially responsible for an increase in breast cancer rates. She told delegates to lobby their politicians to ban chemicals like organochlorine pesticides. WEN's web site at provides a list of environmental links to breast cancer including a number of pesticides such as lindane. Many are already banned but still persist in the environment.

 A recently released video chronicles American anthropologist Elizabeth Guillette's investigation into the harmful side effects of pesticide exposure on children. Playing with Poison, a 46-minute film, asks many questions about the use of pesticides and the effects they are having on our children. Dr. Guillette studied the children of the Yaqui Valley, one of Mexico's largest agricultural areas, providing much of North America's fruits and vegetables, and has had high pesticide use since the 1950s. She compared these children to those of a town in the foothills which is nearly identical except it has no agricultural industry and virtually no pesticide use. The children exhibited significant and disturbing neurological differences; the valley children are far behind those of the foothills in physical co-ordination, energy and learning capabilities. The film also explores the effects of household pesticides and the many ways in which children are exposed to these harmful materials. There has been little research done on the effects of pesticides on humans and her work is slowly breaking new ground. Neurotoxicologist David Carpenter of the University of Albany says, "I have suspected for a long time that pesticides cause these effects, but no one has demonstrated it so convincingly." "I was shocked at the lack of science that exists on pesticides," says North Vancouver's John Ritchie, maker of the film. "That's why making people aware of Elizabeth's study is so important." Playing with Poison originally aired on the Canadian Broadcasting Corporation's The Nature of Things. It is now available through Bullfrog Films at, or by calling 1.800.543.FROG or by email at You can read more about Guillette's study at

 A recently published study in Environmental Health Perspectives documents exposure to pesticides used in low income homes, specifically the exposures of 316 African-American and Dominican women in New York City. "Residential Pesticide Use During Pregnancy Among a Cohort of Urban Minority Women," published in the May 2002 issue (vol. 110, no 5, pp 507-514) finds that 100% of all women monitored had detectable levels of the pesticides diazinon, chlorpyrifos, propoxur and o-phenylophenol and 30% had detectable levels of eight pesticides. Exposure assessments were determined by monitoring 72 women's personal air monitors for 48 hours during their third trimester of pregnancy, to help confirm self-reported questionnaire data. 85% of the women reported using pesticides in their home during pregnancy, roach control being the primary purpose. 9% reported the purchase of illegal pesticides. Exposure levels were higher for African-American woman than for Dominicans. And housing disrepair was closely correlated to the increased use of pesticides. The authors state that "Diazinon exposures for some women may have exceeded health-based levels, and [the] findings support recent federal action to phase out residential use of this insecticide." For a copy of the study, see

 The Proceedings of the National Academy of Sciences published in mid-April the findings of scientist Tyrone Hayes who had recently ended his contract with the chemical giant Syngenta, the maker of atrazine. His independent experiment found that atrazine was linked to high rates of prostrate cancer among workers at a Syngenta manufacturing plant in Louisiana. Another study found that, at a level 30 times lower than the U.S. Environmental Protection Agency's tap water standard of 3 parts per billion, atrazine causes sexual deformities in frogs.

 One of the most eloquent critics of pesticides is Dr. Sandra Steingraber ( author of Living Downstream (Vintage Books, 1998) and Having Faith: An Ecologist’s Journey to Motherhood (Perseus Publishing, 2001). In chapter six of Living Downstream, Steingraber details the research showing how the estrogen mimicking pesticide endosulfan stimulates breast cancer cells to divide and multiply. She says toxaphene is another pesticide that is also estrogenic and a possible cause of some breast cancers. But toxaphene was identified as an animal carcinogen in 1979 and banned in 1982. Endosulfan, introduced in 1954, is still widely used on salad crops. Steingraber appeared on the May 10th PBS program NOW with Bill Moyers. "Children have home and garden pesticides in their urine and they're peeing out wood preservatives," she told Moyers. "Women have termite poisons and toilet deodorizers and flame-retardants in their breast milk. It's time that our public policy takes action to get our kids out of harms way. Let the science go on, let the proof-making and the research happen, but let's keep our kids safe while the research goes on." The transcript of the program is available at

 A study conducted in 2000 at Stanford University showed that individuals who were exposed to pesticides in home or garden were 70 percent more likely to develop Parkinson's disease than those who were not exposed. Other research has determined a link between pesticides and Alzheimer's disease. Parkinson's and Alzheimer's are the two most common neurodegenerative disorders in North America and affect more than a million people, including about one percent of the population over age 60.

 In 1999 European researchers found that Swedish sufferers of non-Hodgkin's lymphoma were 2.7 times more likely to have been exposed to the herbicide MCPA (found in weed and feed type products) and 2.3 times more likely to have been exposed to the herbicide glyphosate (Round-Up).

 According to a Health Canada study of 97 Ontario farmers, 2,4-D, the most common weedkiller on Canadian lawns and golf courses, is often absorbed into the semen of men who spray the pesticide and then passed on to their partners during sex. If the woman is pregnant, the fetus is also exposed to the pesticides. The department wants to know if the men's exposure could harm their children. Health Canada calls the pesticide amounts "trace levels", but did admit the importance of understanding the relationship between pesticide-handling practices, the presence of pesticide residues in semen and the risk of adverse reproductive effects. About half of the men had detectable levels of pesticides, averaging 20 to 30 parts per million in seminal fluid. Those with 2,4-D in their semen generally had it in their urine as well. "Given the importance of semen as a potential carrier of chemicals posing reproductive hazards, it is crucial to understand the relationship between pesticide-handling practices, the presence and levels of pesticide residues in semen and the risk of adverse reproductive outcomes," the department said in a summary of the study, which was published in a research journal called Reproductive Toxicity. The study is the first to make some initial estimates of exposure and comparisons between pesticides levels in semen and urine. The Ontario farmers were not so bad compared with farmers in Argentina, whose 2,4-D levels were as much as 300 times higher than those of Ontario men. The men in Argentina had significant damage to their sperm cells. 2,4-D has been used extensively for the past 40 years, and is one of the main chemicals now under scrutiny in the City of Ottawa's debate on lawn and garden pesticides. In broad-leafed plants such as dandelions, 2,4-D acts as a growth hormone, causing a burst of uncontrolled growth that ultimately kills the weed while not affecting the grass.

 "The cumulative effects of being exposed to many different pesticides over a lifetime represent an unquantified and unacceptable risk to all Canadian children." That unequivocal statement comes from the Environmental Standard Setting and Children's Health Report, released in 2000 by the Ontario College of Family Physicians and the Canadian Environmental Law Association ( as part of the Children's Environmental Health Project. The executive summary of the report is available at

Those are just some of the most recent research studies. There are more I could cite, but I'll stop here. You get the picture. Sandra Steingraber writes how the U.S. EPA classifies chemicals into five categories -- A through E -- to identify their carcinogenicity to humans, with A being known carcinogens, B the probable human carcinogens, C the possible, D the unknown due to lack of data, and E the noncarcinogens. "The fact that numerous chemicals with long-standing membership in Groups A through C are still allowed to be manufactured, sold, released, dumped, imported, exported, or otherwise used comes as a surprise to many knowledgeable people," she writes. Steingraber and I include ourselves here.

What is also surprising is the our Canadian government has passed a new Pest Control Products Act without enshrining the precautionary principle in it as it was asked to do by many, many organizations and individuals. The Stockholm Convention, a treaty to ban the use of 12 persistent organic pollutants (POPs) -- including a number of the worst pesticides -- has been signed and ratified by Canada. Precaution is operationalized throughout the Stockholm Convention, with specific references in the preamble, the objective and the provision on identifying new POPs. Our politicians should have to answer to the public why they are still willing to risk the health of Canadian women, children and the elderly. Bill C-53 ( -- an Act to protect human health and safety and the environment by regulating products used for the control of pests -- was passed by the House of Commons and received first reading in the Senate on June 13. The House and the Senate then adjourned for the summer recess and won't sit again until the week of September 16. There's still time to lobby the Senate to strengthen the bill. Contact information for all current senators is available at

A Swiss study released last month contradicts the claim of some farmers and pesticide producers that pesticides are needed in modern agriculture. The Swiss researchers said organic farming may produce slightly lower yields, but in the long run it is more efficient and much easier on the environment. Organic farms have more fertile soil and a higher biodiversity, both of which have been shown to increase efficiency, the researchers reported in the journal Science. Insects such as pest-eating spiders and beetles flourished in the organic systems. Earthworms and weeds, which can often be beneficial, also were more common in organic farms. The Swiss Federal Research Station for Agroecology and Agriculture in Zurich spent 21 years comparing conventional farming to organic farming, which uses no synthetic pesticides or fertilizers.

On June 28, 2001, the Supreme Court of Canada, in a landmark decision, upheld the town of Hudson, Quebec’s bylaw 207, which bans pesticide use on public and private property for aesthetic purposes. The bylaw had been challenged in the Quebec courts and then at the Supreme Court by lawn pesticide companies after they were charged with violating the ban. The court’s decision goes farther than simply upholding Hudson's bylaws. It points out that the relevant pieces of legislation in other provinces have wording that is comparable. Correctly worded bylaws in other parts of Canada could enjoy the same interpretation as the Hudson bylaw. The Sierra Club of Canada has drafted regionally specific bylaws ( that citizens can take to their local councils to ban or restrict pesticides.

Forty-eight communities across Canada have already established bylaws banning the use of cosmetic pesticides on public and private greenspaces. Parks in the resort municipality of Whistler are now "pesticide free". RMOW parks have long been pesticide free, what’s new is that the "high maintenance" planting boxes in the village are now also pesticide free. BC Rail will also respect Whistler as a "pesticide free" zone, due in large part to the efforts of the RMOW Engineering Department. A growing group of physicians, scientists and environmentalists worldwide have been emphatic in their warnings to governments and the public. Their warnings suggest that the vast majority of these chemicals are linked to a host of childhood and adult cancers as well as numerous other diseases and developmental problems. The Ontario College of Family Physicians, Canadian Association of Physicians for the Environment, members of the Canada Health Advisory Council, Dr. David Suzuki and countless environmental groups are among the Canadians who support this position. If your community is not one of those that has banned the cosmetic use of pesticides on lawns, school grounds and parks, join with other like-minded folk and urge them to do so as soon as possible. You can find out more about school pesticide use reduction at The report Poisoned Schools: Invisible Threats, Visible Actions was released by the Center for Health, Environment and Justice in March 2001. It is available at Unthinkable Risk: How Children are Exposed and Harmed When Pesticides are Used at School released in April 2000 is available from the Northwest Coalition for Alternatives to Pesticides (NCAP) at

NCAP has over 40 articles on alternatives for specific household problems including termites, carpenter ants, dandelions, and roof moss. These articles have information about identification, biology, prevention, habitat modification, as well as physical, biological and least-toxic chemical controls. For example:

 Ants can be controlled by removing their food supply and by sealing their point of entry.  Lawn weeds, such as dandelions, can be prevented by maintaining a healthy lawn. Water deeply but less frequently, and leave grass clippings on the lawn to fertilize.  Carpenter ants can be controlled by removing the nest and replacing damaged wood. They can be prevented by repairing leaky plumbing and by moving wood and branches away from the house.  Slugs and snails can be deterred with traps, beer baits and copper strip barriers.  Tips for other pest problems are available at:

There is no doubt that some pesticides present a great risk to human health. We may not have definitive proof but there is enough to warrant caution. The last word goes to Sandra Steingraber. "What is needed is a new approach to chemical regulation that acknowledges our duty to protect pregnant women from harm. Here is one possible benchmark: if a chemical is not safe for a six-week-old embryo, it is not safe and should not be allowed into the environment." That's the kind of precaution that should have been built into Bill C-53.

RESOURCES - The Green Communities Association at has links to community groups as well as a Pesticide Free Naturally campaign. The testimony of Jean-Dominique Levesque-René to the Standing Committee on Environment and Sustainable Development on September 25, 2001 about how his bout with non-Hodgkin's lymphoma was caused by pesticides is available at His is now crusading to get communities to ban pesticides. Copies of "Pesticides and Your Child: An Overview of Exposures and Risks" are available from CPR! - 412-1 Nicholas Street, Ottawa, Ont. K1N 7B7, phone (613) 241-4611. A lot of resources are available on the Sierra Club of Canada site at Beyond Pesticides is at Canadians Against Pesticides (CAP) is at The Environmental Factor, a successful new generation of lawn care companies that offer such magical products as nematodes to help keep unwanted pests under control. This all-Canadian company was awarded the 2000 Ethics in Action award for its socially responsible business policies. Visit Go for Green - a national, non-profit organization dedicated to encouraging Canadians to be healthy, environmentally responsible citizens. The Go for Green web site hosts ten Garden for Life Fact Sheets that offer how to green your garden naturally. Go to Health Canada’s healthy lawn care site is located at The Elora Centre for Environmental Excellence (ECEE) Pesticide-Free site is located at Halifax Regional Municipal Council passed a bylaw in August 2000 that will ban the use of pesticides on all properties in HRM affected by the by-law commencing April 1, 2003. The bylaw can be downloaded from The best set of links about pesticides including more than a dozen pesticide bylaw sites is at

Michael Jessen is a Nelson-based consultant helping businesses and communities profit by implementing sustainable practices. He can be reached at 250-229-5632 or by e-mail at His business -- Zero Waste Services -- has an award-winning web site at

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