Full of beans, or full of chemicals
Figuring out just how much of a threat herbicides pose to human health is a challenge, as competing studies come to very different conclusions.
Take glyphosate as an example. As the star herbicide of the past three decades, it has been heavily researched, with most epidemiological studies focusing on whether exposure to this compound leads to the development of non-Hodgkin lymphoma, a type of blood cancer. Chemical companies argue it doesn’t, and America’s Environmental Protection Agency (EPA) has determined that glyphosate-based herbicides are “not likely” to be carcinogenic to people. But the International Agency for Research on Cancer (IARC), a UN body, contends that they are, and in recent years several US juries have come to the same conclusion. The agrochemical conglomerate Bayer, which now owns Monsanto, has already paid roughly $10bn to settle cancer claims linked to Roundup. This year the company put up another $7.25bn to resolve future legal battles.
Beyond the risk of cancer, studies on mice show glyphosate disrupts the gut microbiome, and separate research indicates this compound could affect liver and kidney function. The compound has been removed from consumer-grade weedkillers in America, but remains in active use in farming, and is just one in a multitude of chemicals being used today. Research into other compounds like Glufosinate or Fomesafen shows similarly varied results, but as farmers mix and match their herbicides and spray larger quantities on crops, it’s as yet unproven exactly what effect that will have on end consumers and growers alike.
For the planet, however, the problems of using more weedkillers are proven and manifold. Herbicide runoff ends up in streams, rivers and groundwater, killing off aquatic life. Widespread eradication of wild plants removes feeding and nesting opportunities for birds and mammals. Nutrient cycles are disrupted. As the second most grown crop in America, soybean farming has an outsized influence on these trends, and the rise in herbicide-usage-per-bushel of soy compounds is a part of that.
Finally, there is the economic cost of all this spraying. The price of glyphosate on international markets passed $4,000 a tonne this year, and the rates for many other herbicides have ticked up too. Those rising costs of production for farmers are ultimately passed on to consumers. It remains the case that soybeans produced under a cloud of herbicide are cheaper than organic alternatives, and so farmers aiming to maximise yields and minimise costs will keep using them. But it’s also clear that without a change to farming practices, herbicide resistance in weeds will continue to grow, and consumers will pay ever more for increased amounts of chemicals to be sprayed on their food.
