Letters of support from prominent Ottawa doctors:
- Alex MacKenzie M.D., Ph.D.
- Richard van der Jagt, MD, FRCP
- Paul Claman M.D., F.R.C.S.(C).
- Jennifer Armstrong, BSc., M.D.
Letter from Alex MacKenzie M.D., Ph.D.:
Assessment of Pesticide Harm
Despite ample scientific evidence of harm from cosmetic pesticides there will never be consensus as long as the pesticide industry hires scientists to dissect and refute studies. Nevertheless, the evidence of harm is compelling for top medical researchers and doctors who are calling for an end to ornamental pesticide use. This is a brief overview of science in estimation of harm and pesticide evaluation.
What sorts of toxicity are assessed?
Acute toxicity testing is relatively easy – there are quick results, with identifiable outcomes. Today, this testing does not cover the approximately 15% of the population with hypersensitivity to chemicals, nor children and the unborn. Indeed, even acute pesticide poisonings are largely undiagnosed, according to the Canadian Medical Association Journal (May 28, 2002) which notes "Pesticide exposure can cause many different health effects, from acute problems such as dermatitis and asthma exacerbation to chronic problems such as chronic obstructive pulmonary disease and cancer." Unfortunately, potential toxic effects are not limited to immediate toxicity such as irritation.
Long term toxicities are more difficult to determine. One must never forget the lesson of DES, and recognise the possibility of the most important effects appearing in the next generation. (The drug DES, taken for morning sickness, led to daughters' illnesses and cancer after puberty). Delayed reproductive, neurological and immunological changes are all possible. Ills include allergy, intellectual impairment, cancer, autoimmune diseases and frequent infections.
Single agents may be tolerated while multiple chemical effects are potentially devastating, and the logistics of mixture testing are intractable. Even if we had simple, reliable tissue culture models of all effects (we don't), the number of compounds to which people are exposed in this polluted, high-tech, convenience-oriented world means it would be impossible for an army of scientists with the best equipment to carry out the experiments necessary to address all effects of combinations. Science simply cannot examine all eventualities when introducing thousands of never-seen-before chemicals to our environment. Indeed, the long term consequences of additive, cumulative and synergistic effects of pesticides on the health and environment of Canadians are all unknown. Cumulative effects of pesticides not only with the same mechanism of toxicity, but also with differing mechanisms of toxicity are of concern.
Many recent scientific studies are providing strong evidence that pesticides do pose cumulative risks. However, these effects are not considered when registering pesticides. Some toxicities, and only of active ingredients, are examined. "Inert" ingredients can be at least problematic, and cumulative effects are not addressed. When consulted by City of Ottawa staff regarding cosmetic pesticides, the PMRA said that it "cannot address the synergistic nature of products and ingredients because there is no effective way to judge potential element combinations. The potential combinations and dosages are endless." (Ottawa HRSS report, Nov 2002)
Scientific examinations of long term effects of pesticides
Epidemiological Studies
It is not ethical to expose pregnant women to toxic chemicals in order to see the effects on the children, nor can we intentionally expose people to mixtures of pesticides to test for cumulative, additive or synergistic effects. (note: Human single-agent studies have been done in the past, and in other jurisdictions prisoners may still be encouraged to test chemicals. Such information cannot ethically be considered in support of product registration. Nevertheless, it is distributed by the 2,4-D Task Force to Ottawa City Council.)
Information on pesticide effects on people is based on epidemiological studies during the last few decades. These are rife with problems, because these studies are reports of unintentional "experiments" carried out in real life, usually with the subjects self-reporting, little independent or reliable information on actual exposures, and of course no control of a multitude of other variables. Thus any study suggesting pesticide toxicities, for example to farmers, will be subject to criticism because exposure, for example, to diesel exhaust from tractors and sunshine, were not "controlled".
Canada has no tracking of pesticides sales or use. Not knowing what is sprayed where hinders epidemiological studies. Epidemiologists need both tracking of pesticides and full disclosure of pesticide compositions.
Advances in testing, diagnosis and medical care mean that today’s diagnostic data, not only for cancer but for other ills as well, cannot be compared to historical controls. For example, we don’t really know how many "bad boys", in a different society and educational system fifty years ago, really had ADHD, or how intelligent or physically co-ordinated the population really was. You cannot compare illness rates between time periods with and without antibiotics, with different standards of hygiene, nutrition and health care.
However, one remarkable epidemiological study by Dr. Elizabeth Guillette is unfolding. She tells a compelling story about extensive intellectual and physical compromise of "normal" Mexican children exposed to pesticides, in comparison to an otherwise very similar population not exposed. Her work highlights the chilling possibility that significant community-wide deficits go largely unnoticed, but are real and immediate threats to our future.
Animal studies are problematic, because of difficulties extrapolating results to humans, and for the logistical reasons discussed above.
Laboratory studies of tissues in culture are also difficult to extrapolate to people. This is relevant because this sort of study is used to test new drugs. If we had reliable models, more effective treatments for cancer would have been found. We don’t even know how to model some relevant effects in the laboratory, much less project combinations of a variety of impacts. Once again, the sheer numbers of necessary experiments renders this approach impossible, even if reliable methods were in place.
Sound Science
While the PMRA claims to base its decisions on "a scientifically based approach", in fact, and by their own admission to Ottawa staff, thorough scientific examination of relevant questions is impossible. Furthermore, registration would more properly be based upon peer-reviewed scientific analysis conducted in an open public forum. Testing data provided by the industry is considered confidential. Most of the formulation is secret. Secrecy has no place in science.
The PMRA is apparently unworkable. Many pesticides now in use were approved before current testing criteria were in place. They are being slowly re-evaluated, and many are eventually removed from use due to toxicity. Some pesticides now in use on Ottawa lawns and gardens have been known to pose unacceptable risks for over a decade, and would not be approved if brought forward today. Some are destined to be removed from use eventually. In the meantime, people's health is compromised. According to the Auditor General (2002) criticising the Federal Government with respect to pesticides "…its ability to detect, understand, and prevent the harmful effects of toxic substances is still limited. The processes we observed seem to defy timely, decisive and precautionary action."
Decisions regarding pesticides balance risk and benefit. Pesticides pose an inevitable risk. It is a political decision as to the level of benefit that merits the risk. Ornamental pesticide use benefits do not merit the risk. I strongly believe that all levels of government should do whatever is within their jurisdiction to curtail frivolous uses of pesticides.
Alex MacKenzie M.D., Ph.D. Director CHEO Research Institute Paediatrician, Children's Hospital of Eastern Ontario Professor, Faculty of Medicine, University of Ottawa
Letter from Richard van der Jagt, MD, FRCP:
Re: Federal Review of Pest Control Products Act
I am writing to urge that the federal government demonstrate strong leadership and vision in the continued pursuit to eliminate the cosmetic use of lawn and garden pesticides within our country.
I am writing to you as a physician, and Chair and founder of the Canadian Leukemia Studies Group, a collaborative research group across Canada, parts of the USA, and which is now developing ties with centers in Sweden, Israel, and China. I am also trained in Epidemiology. I strongly support practical and sensible initiatives in preventative medicine, and I urge that Canada join the other countries that have shown leadership many parts of our globe, to eliminate the cosmetic use of pesticides. There is now strong evidence linking pesticide exposure to acute leukemia in children (the most common cancer in children), to breast cancer (the most common cancer in women), and to prostate cancer (the most common cancer in men). There is also clear evidence linking pesticide exposure to neurotoxic effects, to birth defects, to non-Hodgkin’s Lymphoma, to Parkinson’s Disease, and to bladder cancer. This harkens back to the days when evidence was emerging on the risk of tobacco smoking. I do not think it appropriate for politicians to be debating the weight of medical evidence linking pesticide use and the risks of leukemia, non-Hodgkin’s lymphoma, prostate and breast cancer, infertility, and possible birth defects, developmental delays and other neurological disorders, as precaution must be the overriding principle. In any case such as this, where there are serious implications to human health and the environment, the precautionary principle must apply. Logic and reasonableness cannot argue otherwise. Note that the US Environmental Protection Agency has chosen to adopt a zero tolerance to any additional health risk posed by pesticides.
I understand the tremendous influence that the pesticide industry may have on decision-making processes to ban the use of their non-organic products. When it comes to assessment of the effects of the 800 chemicals now being dumped into our environment for "cosmetic " use, it is at times difficult to prove on a case by case basis how much any one chemical is responsible for the overall effect seen in epidemiological studies. As above, the evidence is irrefutable and cannot be ignored.
Please do not underestimate the very strong views of many constituents who silently oppose and object to the spraying of these toxic substances into the environment where we live, and where our children play. I find it positive that some companies have been able to capitalize on business opportunities from the marketing of safer and effective alternatives to chemical pesticides for lawns and gardens.
As those now being charged with caring for the health of our national well-being, and for the long-term health of our children and all future generations, I urge you all to take the lead in restricting the cosmetic use of pesticides in Canada by 2003.
Yours sincerely,
Richard van der Jagt, MD, FRCP, Assoc. Professor of Medicine, University of Ottawa, Chair of the Canadian Leukemia Studies Group, Ottawa Hospital, General Campus, 501 Smyth Road, Ottawa, Ontario K1H 8L6
Letter from Paul Claman M.D., F.R.C.S.(C): Re: Bill C-8 and the control of pesticide use in Canada and the Pest Control Products Act
To the Honourable Members of the Senate:
Virtually all studies on the effects of pesticides on human fertility are either case reports or epidemiological ( ie. Population based, Case Control or Cohort studies). As such it is difficult to obtain clear evidence on their adverse effects compared to a prospective placebo control study of a new medication for the treatment of a disease. However, the available studies provide very compelling data showing that pesticides likely have profound adverse effects on human reproduction. Exposure may reduce sperm counts, affect egg quality, increase miscarriage risk and increase the risk of birth defects. Adverse effects of some pesticides have been reported in animal studies lending biological plausibility to the argument that pesticides may lead to reproductive problems in people.
The experience of infertility is one of the most severe forms of human suffering for those couples who desire children. Although assisted reproductive technology can help couples have children even when there are severe infertility problems, these treatments are invasive, expensive and do not always work. As such it is incumbent on employers and regulators to minimize exposure to the population from those toxins where there is any evidence that they might lower fertility potential.
Pesticides should not be used in our country for cosmetic (e.g. lawn care) purposes and agricultural workers need to be warned with careful labeling to minimize exposure by use of protective clothing and careful application techniques. Government leadership needs to be stringent in its interpretation of the evidence extant in favour of protecting Canadians from pesticide exposure since they likely have profound adverse effects on Canadian citizens’ ability to have healthy children when they elect to do so.
Sincerely,
Paul Claman MD
Letter from Jennifer Armstrong, BSc, M.D.:
To: The Senate Committee reviewing Bill C-8, the Pest Control Products Act
My expertise is in the field on Environmental Medicine. Several of my colleagues have already contributed some great information to your committee through CAPE and OCFP. My colleagues send me the sickest of the sick. I am called the last-hope doctor. I have been intensively practising environmental medicine for 6 ½ years, and due to my work have been elected to the Board of Directors for the American Academy of Environmental Medicine. My Canadian colleagues are actively running two research centres in Canada; one is affiliated with the University of Dalhousie and the other is affiliated with the University of Toronto Environmental Health Unit. Please find attached Hospital Guidelines for Environmental patients written by our CSEM (Canadian Society for Environmental Medicine) the first Hospital guidelines of its kind in the world written to educate hospital staff on how best to take care of an environmentally ill patient.
My degree in medicine is from U of T (‘77), after receiving a degree in Biochemistry (Carleton ‘73). I spent the first 8 years of my life as a doctor practising in the rural parts of Texas. It was very enlightening, there was great opportunity to apply almost everything that I was taught in my excellent teachings at the University of Toronto, but something was missing. . . . if I really stood back and took a look at what I was doing, I was not truly helping people. Kids kept coming back with ear infections and hyperactivity, adolescents kept coming back for drugs for asthma, acne, and anxiety, adults kept having depression, decreased libido, insomnia, and migraines, and all I was doing was pushing pills. Many of these symptoms are seen in a patient who has low grade neuro-toxicity from pesticides -- not a diagnosis any of us would normally look for.
Fortunately I stumbled upon the field of Environmental Medicine, which is now gaining recognition in its ability to treat patients by identifying and eliminating causes of problems, and rather than using medications for each symptom. Why does a patient develop ill health? Emphasis was placed on taking a history of patients' exposures. Instead of treating one symptom at a time we were taught to look at the constellation of symptoms to see if there could be a common denominator. Multiple symptoms, like a puzzle, fit into the picture of a greater whole, especially once a cause is identified. By eliminating the offending agent(s) or cause, several if not all of the multiple symptoms can be resolved. Doctors may be taught to shun a patient with multiple symptoms as a hypochondriac. However a patient, for example with a toxic mould exposure, will experience multiple system involvement, such as sinusitis & bronchitis (respiratory), fatigue (central nervous system), muscle aches (musculo-skeletal), chest pain (cardiovascular), itchy rashes (skin), and nausea and vomiting (gastro-intestinal). Thus, at least 4 systems of the body are involved in one exposure. If a family doctor sent this type of patient to a different specialist for each problem, the patient would possibly get a drug or two for each system. This patient’s liver would then become greatly stressed, adding more insult to injury of the already toxic load of mould on his liver. Taking a good history may have been able to elicit a common underlying problem in a patient such as this. Several of my colleagues sit on the College of Family Practice Environmental Health Committee to help improve knowledge of Environmental Influences on Health -- especially how to better take a history.
The incidence of chemical sensitivities at this time is at least 15% of the population; that is, patients who are aware that they are reacting to chemicals. Many chemicals in this world can cause havoc in our bodies, causing multiple symptoms. Illness can be induced by a single large exposure to any chemical, but especially to pesticides. There are many more people who are probably not aware that their symptoms are caused by chemical sensitivities.
Just breathing a whiff of a few ppm of a chemical can cause a sensitive person to get a headache, become irritable for no apparent reason, have extreme fatigue which can last for hours, have abdominal cramps, develop muscle aches, trigger asthma and seizures, or have severe enough "brain fog" to totally incapacitate them for several hours or days.
According to research by Dr Roy Fox of the Halifax Environmental Unit, approximately 5% of the population will experience some degree of mild symptoms from exposure to pesticides while 1% will experience severe reactions to pesticides, and 0.1% will experience life threatening reactions such as anaphylaxis. In the Montreal study, 36% of children had a genetic subtype unable to breakdown pesticides, leading them to increased vulnerability to adverse health effects, such as cancer. These are two different health problems; one is cancer the other is environmental sensitivities. There may, however, be a link because unfortunately many of our patients go on to get cancer.
From taking careful histories of my patients there is no question that there are an increasing number of patients reacting to pesticides. I now have a 2 year waiting list; many patients calling up desperate for help. There are few physicians who are trained to look at how the environment is affecting their patients health, or how to treat it. I clearly see patients start getting better from terrible illnesses once they start removing pesticides from their life.
The Ontario College of Physicians clearly outlined the problem with dealing with industry. Although mandatory reporting of health effects would be a great idea, I strongly believe that it will be under-reported until more physicians have had training in environmental medicine. For example, a new onset of psychosis could be caused by pesticides. Without proper avoidance and treatment that patient could be imprisoned by unnecessary drugs for the rest of his/her life.
I will submit as an example a DNA study done on one of my patients. Please note how the DNA has been studied for polymorphisms in expression of the gene – how much the gene is used as a blue-print to make proteins. On page 6 we see this patient has only 50% of the normal production of the enzyme COMT. This patient has difficulty breaking down neurotransmitters, which can lead to depression, ADHD, bipolar disorder and alcoholism. This is the type of patient that may have psychiatric-type symptoms from exposure to pesticides.
Medicine is becoming harder to practice when so many patients are having multiple symptoms. Reduce the "chemical soup", starting with the pesticides, and I assure you that you will see a much healthier population. This would be a great benefit to the budget of the medical system. Unnecessary use of pesticides as outlined by many other people before your committee is compromising the ability of environmentally ill patients, and others not yet properly diagnosed as sensitive to chemicals, to recover. Even small doses of pesticides can affect a person according to research by Dr. Roy Fox at the Halifax Environmental unit.
Please establish mandatory reporting and labelling of all chemicals in products sold to the public, and reporting of symptoms. Patients and their physicians would be better informed -- the first step towards a more reasonable diagnosis, a less drugged patient, and a happier doctor who feels less helpless when patients have such puzzling constellations of symptoms. A federal program on research in toxicology would be a marvellous tool to identify how the myriad of chemicals affect our patient population.
Sincerely,
Jennifer Armstrong M.D. Ottawa Environmental Health Clinic
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