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The Perils of a Dog Park Are Not Always Visible

Roundup kills weeds but what about everything else?

We have lived on Miami Beach for twenty-one years, far longer than we expected to live anywhere, but especially here on the edge of the tropics. We chose this neighborhood, as we have chosen all of them for over three decades, in large measure because there was a park two blocks away where people and dogs could get some exercise, and there was the beach just a couple of blocks beyond that. When we moved here, it was still possible for discrete scofflaws to walk the park or beach with their hounds without risking a ticket or exposure to toxic substances liberally applied in the name of weed and pest control.

In the immediate aftermath of Hurricane Andrew, the park was turned into a seven-acre dumping ground primarily for tons of vegetation and roof tiles, the tightly wound storm having rained its most destructive blows on Homestead, thirty miles to the south. Even after the last of the debris was cleared away, the park remained dilapidated. That official neglect made the park ideal not only for a small cadre of off-leash walkers who considered it theirs by default but also for poachers out to claim part or all of it for their favorite activity. The police erected a chain-link fence and declared that they were simply rebuilding a K-9 training facility that Andrew had blown away. Neighbors with memories protested, but who among politicians would resist the police, who decided the park outside their pen was a parking lot. They ignored completely an explicit ban on all motorized vehicles in park.

The city’s answer to the repeated violations was a big, new18-slot parking lot tucked inside indifferent landscaping and nicely tied into the asphalt covered pathway. A general relandscaping came to include a two-part “dog park ” designed to look like a dog bone, not that anyone could tell from ground level. The parks department soon started boasting of its dog-friendly additions via inserts to utility bills, among other things.

With the neighborhood demographic turning over from aged residents with no children at home to younger families with sometimes many children and dogs, the little seven-acre park went beyond overcrowded. The parking lot and advertising drew increasing numbers of people, including drive-ins from well beyond the neighborhood, many of them with multiple dogs. At peak hours, the park would be awash with people and dogs inside and outside the chain-link dog bones. Cluelessness about the behavior of dogs and people often led to inter- and intraspecies conflict

The dog park quickly became a breeding ground not for dogs but for the fleas and ticks that feasted on them. Weeds that had once flourished were no longer tolerated. The city routinely sprayed the dog park with Talstar, a potent pesticide, and liberally spread a bluish green liquid wherever a weed dared sprout. A few questions revealed the weed eater was Roundup, to which color had been added for easy identification.

First marketed by Monsanto in 1970, Roundup had become a free agent by 2000 when the main U.S. patent expired. Its active ingredient, glyphosate, promptly became the most widespread herbicide in the world by a huge margin. Meanwhile, Monsanto began marketing “Roundup Ready®” seeds that allowed farmers to kill weeds right up to harvest. Their soy, corn, rapeseed—canola—cotton, sugar beets, and alfalfa had been genetically modified by Monsanto to withstand liberal applications of Roundup, particularly its main ingredient glyphosate.

My wife and I had become interested in Roundup some years before we found it in our local park primarily because of Monsanto’s near feudal impositions upon farmers who use its seeds. We doubted, too, that anything so lethal to plants would not be somehow genetically deleterious to humans and animals. Finally, little news items kept popping up about weeds developing their own immunity to Roundup.

By the turn of the millennium, reports were piling up associating exposure to Roundup with non-Hodgkins lymphoma, fertility problems, and Parkinson’s Disease, among others. I was diagnosed with Parkinson’s in 2002, well before we discovered Roundup liberally sprayed in the park but on the chance that these reports were pointing to something real, I raised a ruckus with the city and demanded that its use be discontinued. I argued that even if weren’t toxic to humans, it was to amphibians and birds and thus should not be used in a nature preserve, which technically our park is.

About that time the police abandoned their fenced training area and the city agreed to turn it into an organic community garden. With that designation several of us in the neighborhood figured we could keep Roundup out of the park.

We were wrong. Since the first promise to discontinue use of Roundup in our park and other public spaces frequented by animals and children, I have caught groundkeepers spraying Roundup there at least three times and raised an alarm each time. Officials in the parks department initially denied my complaints—effectively called me a liar—before admitting that the substance in question was Roundup.

The second time I caught them was at the end of the garden’s first winter—the growing season in South Florida—when city workers sprayed the organic community garden with Roundup without posting a notice or telling anyone. We spotted the identifying stain and immediate sent out a notice. The parks department denied and obfuscated before the garden coordinator asked the groundkeeper directly. He confirmed that Roundup was used.

The city changed its ways a little. Indeed, last fall, when I observed a man spraying a colorless liquid around trees and along asphalt pathways, I asked what it was, and he said, “Roundup.” It is common to mix color with Roundup so that people spraying can easily see where they have applied it. But in this instance, I can only assume the intent was to conceal, because Roundup is so addictive that the parks department, like its counterparts in other cities and its own citizens on their own property, cannot give it up. Its potency and the myth of its safety make it impossible for them to renounce.

Yet it is worse than a lethal cocktail of DDT and Agent Orange if even half of what Anthony Samsel, an independent scientist in Durham, New Hampshire, and Stephanie Seneff, a computer scientist at MIT, write in the April 18, 2013, edition of Entropy. They provide an exhaustive meta-analysis of existing scientific literature on the effects of glyphosate on mammals, including and especially humans. If glyphosate is responsible for even one of the diseases and conditions they name, it should be banned. If their broader argument is proved correct, and it certainly looks solid, then glyphosate is worth a special spot in the deepest recesses of chemical hell. They name obesity, inflammatory bowel disease, Crohn’s disease, autism, dementia, Alzheimer’s disease, Parkinson’s disease, depression, anorexia nervosa, fertility problems, liver disease, and cancer.

That is quite a list for something that is supposed to be nontoxic to mammals because it works on the shikimate pathway that is found in plants but not animals. The shikimate pathway is involved in production of the amino acids phenylalanine, tyrosine, and tryptophan. That assessment overlooks the presence of shikimate pathways in gut bacteria found in all mammals, Samsel and Seneff say, and it is there that glyphosate wreaks havoc.

Chief among glyphosate’s multiple malfeasances in the gut is its inhibition of cytochrome P450 enzymes, which are essential in detoxifying xenobiotics. Gut bacteria also aid digestion, synthesize vitamins, and contribute to immune responses. Samsel and Seneff lay out a detailed argument, during which they point out that glyphosates appear to have no effect on animals in short-term rat studies, but the results are dramatically different when the term of the experiments is extended.

Samsel and Seneff’s argument is so extensive and so damning that I suspect it will initially be attacked as misguided and wrong, dismissed because it did not appear in one of the major scientific journals. But it is too important to ignore completely. At our house, because of studies implicating other agricultural chemicals with neurological disease, we’ve for many years tried to buy only organic produce, and we will redouble out efforts in light of this paper. The dog eats organic food as well.

There are seen and unseen costs to humans’ reshaping of the planet. Samsel and Seneff’s study about the unexpected consequences of a chemical that has been so readily and widely spread throughout ecosystems globally should cause us to think through ways to integrate our lives and society more fully with the world that is our home and to meddle with caution. But will it?