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Almost a decade ago, the European Environment Agency (EEA) published its report titled, Late lessons from early warnings: the precautionary principle 1896-2000. The report is based on selected case studies from the last century detailing how inaction to early warnings resulted in late lessons learned some decades later.
Such examples are well known to us today: Marie Curie died from her discovery of ionising radiation, the ozone damage caused by chlorofluorocarbons (CFCs) will continue to increase our risk of skin cancer for the next 50 years, during which thousands will die from asbestos induced mesothelioma. The hazards of these beneficial technologies were not known about, and perhaps could not have been known about until it was too late to stop some of their irreversible effects. In the context of such unprecedented scientific progress, the EEA called for a better understanding of the use of the precautionary policy in public policy making.
The precautionary principle states that if an action or policy has a suspected risk of causing harm to the public or to the environment, in the absence of scientific consensus that the action or policy is harmful, the burden of proof that it is not harmful falls on those taking the action.What scientists now know is that our politics and regulatory frameworks are grossly inadequate to protect the public from the present and future consequences of pesticide use and exposure. A decade of research into their endocrine-disrupting effects has resulted in some conceptual shifts in scientific thinking that suggest it's about time we implemented the precautionary principle.
Current Pesticide Risk Assessment Policies Are Neither Safe Nor Precautionary
Current procedures no longer reflect the progress in scientific understanding that has been made over the last decade. Toxicity risk assessments are being made without consideration of current research findings, and without consideration of their combined and additive effects. It's rare for a single pesticide to be used on a crop. Consequently, many substances of known and serious risk are currently being allowed to accumulate in the environment to concentrations that can potentially cause irreversible harm.
Current pesticide policies worldwide require substantial evidence of harm before regulatory action is taken, regardless of the availability of safer alternatives.Effects of Pesticide Exposure Are Not Dose-dependent Endocrine Disruption Can Occur at Extremely Low concentrations Once Thought to be Safe
Children are particularly vulnerable to the adverse effects of pesticide exposure, and especially during periods of rapid growth and development. Recent research indicates that children may be up to 164-times more sensitive to organophosphates, rendering a current safety factor for children of 10-times to be insufficient. Every day in the US, 90% of children between six months and five years of age are exposed to a combination of 13 different organophosphate insecticides in food. In relation to their body weight, children also consume a larger intake of pesticides in their diet than adults. 6 times more fruit, 2 times more vegetables and 3 to 5 times more cereals.
Indoor concentrations of pesticides have been found to exceed those outdoors. Young children spend comparatively more time indoors and crawling at ground level where pesticide residues, household and garden chemicals may increase their exposure.
A 2005 systematic review from the University of Liverpool concluded that low levels of synthetic pesticides and organochlorines could be major factors in the development of cancers. They cautioned that chemicals can be carcinogenic in children at parts per billion and parts per trillion levels, rather than parts per million and thousands.
Testing Single Compounds and Their Short-Term Effects on Healthy Adults Does Not Reflect the Real World Environment We Live In
Studies have associated pesticides with elevated risk of kidney cancer, brain cancer, haematological tumours in children (non-Hodgkin's lymphoma and leukemia), especially the use of some types of household insecticides during pregnancy and childhood. We know that children are constantly exposed to low levels of pesticides in their food and environment, yet there are few studies on the long-term effects of these exposures.
It has been known for some time now that the developing foetus is vulnerable to many environmental toxins which can cross the placenta and that infants can be exposed through breast milk. Recent evidence now suggests that since the female ova are formed in the foetal stage, the next generation of children may be affected by their grandmother's exposure. Preliminary research with vinclozolin, a common fungicide used in vineyards, found that exposure in rats could lead to DNA alterations that lasted for four generations. Other studies of vinclozolin have found that while adverse effects on adult animals were reversible, they were generally irreversible on young animals.
What Needs to Happen Before the APVMA Can Take a Chemical Product Off the Australian Market?
The Australian Pesticides and Veterinary Medicines Authority (APVMA) is responsible for regulating all agricultural and veterinary chemical products, including chemicals which are used in the household, such as insect sprays, personal insect repellents, products for treating diseases in home garden plants, and medicines for companion animals such as dogs, cats and horses.
For any of the 8,000 registered chemical products to be taken off the market, the APVMA must be satisfied that there is likely to be a causal link between the use of a registered product and an unintended harmful effect when that chemical product is being used correctly. Credible scientific studies are typically required to define the link and identify the resultant risk.The European Union currently leads the way in changing its policies towards pesticide regulation. Meanwhile, controversial compounds cancelled in the EU such as Atrazine, Bifenthrin, Endosulfan and Permethrin continue to be used in Australia.
This is a question that deserves to be asked by all Australian consumers and their doctors: what needs to happen before the APVMA will take precautionary measures to protect the health of our children, and that of our wildlife and natural environment?
Precautionary Recommendations
Most recently, the President's Cancer Panel was particularly concerned to find that the true burden of environmentally induced cancer has been grossly underestimated. Clinicians working with children and at-risk patients are advised to read the full report and consider its recommendations:
- Clinicians should routinely question patients about their previous and current workplace and home environments, and this information should be incorporated into medical record keeping systems.
- Public health campaigns should be developed to raise awareness of environmental cancer risks and encourage people to reduce or eliminate exposures wherever possible.
- To the extent possible, parents and child care providers should choose foods, house and garden products, play spaces, toys, medicines, and medical tests that will minimise children's exposure to toxins.
- Exposure to pesticides can be decreased by choosing certified organic foods grown without the use of pesticides or chemical fertilisers. Washing or peeling conventionally grown produce can remove some surface pesticide residues.
- Family exposure to numerous occupational chemicals can be reduced by removing shoes before entering the home and washing work clothes separately from other family laundry.
- Ideally, both parents should avoid exposure to endocrine-disrupting chemicals and known or suspected carcinogens prior to a child's conception and throughout pregnancy and early life, when risk of irreversible damage is greatest.
- Each person can become an active voice in their community. Individuals have the power to affect public policy by letting policymakers know that they strongly support environmental cancer research and precautionary policies against known and suspected chemicals.
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