A relatively unknown pesticide linked to infertility, disrupted fetal growth and delayed puberty can now be found in the bodies of 80% of Americans, a new study has shown.
Chlormequat chloride, a plant growth regulator, used on grain crops in Europe and parts of North American, was detected in 77 of 96 American urine samples collected between 2017 and 2023, and 90% of the samples from 2023, raising public health concerns.
The chemical is approved for use on food crops in the European Union, the United Kingdom and Canada, mainly on wheat, oats, and barley where it acts to decrease stem height in order to make harvesting easier.
The Journal of Exposure Science & Environmental Epidemiology study found that 92% of tested conventional oat-based products contained chlormequat, compared to 12.5% of organic ones.
22% of conventional wheat-based products tested in February 2023 also contained traces of the highly toxic agricultural chemical.
Affected brands included Kellogg’s, General Mills, Quaker, Target and Walmart, and chlormequat was detected in products such as Cheerios, Special K and Quaker Oats.
“Given the toxicological concerns associated with chlormequat exposure in animal studies, and widespread exposure to the general population, in European countries, and now also likely in the U.S., monitoring of chlormequat in foods and people, in conjunction with epidemiological and animal studies, is urgently needed to understand the potential health harms of this agricultural chemical at environmentally relevant exposure levels, particularly during pregnancy,” the authors noted.
The US first allowed the importation of food treated with chlormequat in 2018, even though it it not approved for use on food crops in the US.
In the UK and the EU it is the most detected pesticide residue in grains and cereals, and was found in 100% of Swedish adolescents tested between 2000 and 2017, and traces exist in 90% of bread sold in the UK.
According to the study authors, chlormequat “exhibits concerning toxicological properties” and was first noticed by Danish pig farmers who saw reproductive declines in animals raised on grains treated with the chemical.
Later experiments showed “female pigs fed chlormequat treated grain exhibited disrupted oestrus cycling and difficulty mating” and “male mice exposed to chlormequat via diet or drinking water during development exhibited decreased fertilization capacity of sperm in vitro”.
“More recent reproductive toxicity studies on chlormequat show delayed onset of puberty, reduced sperm motility, decreased weights of male reproductive organs, and decreased testosterone levels in rats exposed during sensitive windows of development, including during pregnancy and early life,” the study said.
“Developmental toxicity studies also suggest that chlormequat exposure during pregnancy can dysregulate fetal growth and metabolism.
“Other investigations did not find impacts of chlormequat on reproduction in female mice, male pigs, or a subsequent investigation of fertilization capacity in male mice developmentally and postnatally exposed to chlormequat.”
This could be due to differences in testing dosages and selection differences, the authors said.
The Environmental Working Group, which conducted the research, said the study “rings alarm bells” due to the potential for harm to humans posed by chlormequat.
“Chlormequat was not allowed on oats sold in the US before 2018, when the Trump EPA gave first-time approval for some amount of the chemical on imported oats,” the EWG said.
“The same administration in 2020 increased the allowable level. These regulatory changes might help explain why we’re seeing more frequent, higher detections of the chemical in Americans tested.
“In April 2023, in response to a 2019 application submitted by chlormequat manufacturer Taminco, the Biden EPA proposed allowing the first-ever use of chlormequat on barley, oat, triticale and wheat grown in the US.”
