A US study has found that glyphosate, the active herbicidal ingredient widely used in weed killers like Roundup, is present at low levels in a variety of store-bought dog and cat foods.
The study—published in Environmental Pollution—grew out of a larger interdisciplinary research project led by Brian Richards, at Cornell University, NY, and supported by the Atkinson Center for a Sustainable Future’s Academic Venture Fund, which sought to reassess glyphosate mobility and impacts in several contexts: movement from crop fields in surface water, impacts on soils and on animals consuming it in their feed.
The team visited a pet store and a retail outlet, where they selected multiple bags of cat and dog foods from major brands. The 18 feeds were all mixtures of vegetable and meat ingredients, and one product was certified GMO-free.
Analyses conducted found that all of the products contained glyphosate at concentrations ranging from approximately 80 to 2000 micrograms of glyphosate per kilogram.
Since there is not enough data available to determine what effect—if any— low-dose glyphosate exposure has on domestic animals, the researchers used human acceptable daily intake guidelines to put these findings in context. They estimated that the median dog exposure would amount to only 0.7 per cent of the US glyphosate limit set for humans.
“While the levels of glyphosate in pet foods surprised us, if a human ate it every day, their glyphosate exposure would still be well below the limits currently deemed safe,” co-investigator Anthony Hay said.