Urban Chemicals and Risk

We all love a weed free lawn, and we all know how to get it: we purchase the appropriate chemical and apply it to our lawn ourselves, or we contract a lawn care professional to take care of the problem. When we do that, do we give any thought to the possible harmful effect of that chemical to our health, our children’s health or our neighbor’s health? Let’s face it; most of us have not given this question a moment’s thought. However, those of us who watched the documentary movie, A Chemical Reaction last week found ourselves thinking about that very question.

No one should be surprised that many studies have been carried out around this very question, and no one should be surprised that the studies are not consistent. If this question interests you, the Manitoba Eco-network has some excellent links. (You could also go to the chemical company web site and check out their studies.) The dilemma is clear: a conscientious parent will know that there is a possibility that using chemical lawn care products on the lawn her children play on will increase their risk of contracting certain cancers or neurological disorders. Not every one is equally susceptible, but the risk is there for everyone. On the other hand, a weed free lawn is appealing. Is the risk, particularly to our children, worth it?

We also heard from Lorne Peters and David Dawson, two local beekeepers. They spoke of the threat pest control chemicals pose to bees. Any beekeeper will wait four days after spraying Malathion before he puts bees into a clover, canola or sunflower field. These insect specialists (which is what beekeepers are), found it unthinkable that spraying for nuisance mosquitoes will affect only mosquitoes. Spraying with Malathion will affect not only mosquitoes, but also bees, dragonflies and butterflies. And what effect will that have on the birds that normally feed on these insects?

The use of malathion for the control of nuisance mosquitoes raises questions of human health as well. It is known that Malathion is a neurological insecticide. Studies done in Winnipeg, the only major city in Canada with an ongoing Malathion nuisance-adult-mosquito-control program, have found the risk acceptable. Obviously, this is a value judgment. It is clear, of course that we humans have a greater tolerance for these neurological chemicals than insects do. We have all seen flies in a death spin as a result of insecticide exposure, and we, the watcher, who were exposed to the same chemical, were fine. But how confident can we be that repeated exposure to this neurological chemical does not have a cumulative effect? And how confident can we be that the studies done have taken into account the cumulative effect?

Many of the things we do involve risk. When we use chemicals for cosmetic reasons or in order to reduce nuisance insects, we need to be clear on the risks involved, particularly for our children.

Eric Rempel