Partnering with EHN.org, the environmental wellness blog and community had the oat milks tested by a U.S.-Environmental-Protection-Agency-certified lab for glyphosate and heavy metals. They found traces of glyphosate and arsenic in MALK Organic Oat Milk at 12 parts per billion, and glyphosate in Silk Extra Creamy Oatmilk at 14 parts per billion.
“Oat milk is consumed by many people as a drink alternative that goes into coffee, cereals, baked goods, and other foods,” Linda Birnbaum, scientist emeritus and former director of the National Institute of Environmental Health Sciences and National Toxicology Program, told Mamavation. “One exposure would be fine, but daily exposure is concerning. “
Glyphosate is the most widely-used herbicide in the world and linked to number of human health problems including cancer, neurological diseases, endocrine disruption and birth defects. Arsenic is linked to cancer, cardiovascular disease and developmental impacts to children.
EHN.org partially funded the testing and Pete Myers, chief scientist of Environmental Health Sciences, which publishes Environmental Health News, reviewed the findings. The report builds EHN.org and Mamavation’s growing library of consumer products tested. For example, recent testing found evidence of PFAS chemicals in contact lenses.
Other scientists who reviewed the results said the two products with contaminants are cause for concern.
“Glyphosate residues in food products are troubling at any level,” Terry Collins, Teresa Heinz Professor of Green Chemistry & Director of the Institute for Green Sciences at Carnegie Mellon University, told Mamavation. “Clearly, the company with glyphosate and arsenic above 10 [parts per billion] would be well advised to discover why these are there and eliminate them.”
Collins also pointed to the good news: most brands had no detectable levels of the herbicide.
“And it is encouraging that most products were found to be free of such heavy metal contamination above 10 parts per billion,” he added.
Glyphosate has been found in a variety of oat products, including oat meals and cereals, as well as some lentils and barleys. Some experts believe late season glyphosate spraying — which hastens the drying out process for crops in the field — is the culprit.
“I used to eat oat products frequently, but when I learned about pre-harvest desiccation I stopped eating any oats that weren’t grown organically,” Myers told Mamavation.
Heavy metals can get into food from soil, past pesticide use, manufacturing or storage.
Mamavation found no glyphosate or harmful metals in oat milks from Three Trees, Rise Brewing, Oatsome, Kirkland, Califia, Planet Oat, Oatley, Nut Pods, Elmhurst and Chobani.
“It’s important to select products that do not have detectable glyphosate or other heavy metals in order to protect your family (and yourself) from the complications that can arise from daily exposure to hormone-disrupting chemicals,” Birnbaum said.
Scientists looked at 172 categories of consumer products, from cosmetics to cleaning agents, and found that 105 included chemicals regulated by California due to health impacts.
The U.S. tends to regulate chemicals in isolation, Dr. Megan Schwarzman, a physician and associate director of the Berkeley Center for Green Chemistry at the University of California, Berkeley, who’s an author on the study, told Environmental Health News (EHN). “This study really highlights the extent of the potential aggregate exposures, multiple sources of the same chemical and co-exposures, exposure to multiple chemicals from the same source,” she said.
In the home, general cleaners, laundry detergent, dishwashing soap and nail coatings had the largest number of toxic chemicals present. Adhesives, autocare products, cleaners and lubricants rose to the top of concerning workplace exposures. Many known toxic chemicals could be found in use across these categories, meaning people could experience exposures from multiple sources. Researchers hope these findings will help prioritize a move away from harmful chemicals people are repeatedly exposed to, and reformulation of products with safer alternatives.
In the home, general cleaners, laundry detergent, dishwashing soap and nail coatings had the largest number of toxic chemicals present.
Credit: Tetiana SHYSHKINA/Unsplash
Product labels aren’t required to include all chemicals present and their quantities, explained Schwarzman, so researchers turned to a database of chemical emissions from consumer products maintained by the California Air Resources Board. The board collects ingredient information from manufacturers of products sold in the state, and estimates the total emissions from the products to monitor contributions to smog. The database includes only volatile organic compounds, one type of toxic chemicals regulated by California, so other kinds of chemicals weren’t considered in the study.
“We were able to point to several chemicals that are in widespread use, and in many cases are used for functions that are not essential,” Claudia Polsky, director of the Environmental Law Clinic at the University of California, Berkeley and author on the study, told EHN.
Diethanolamine (DEA) stood out to Dr. Schwarzman for its widespread use, despite being listed by California as a carcinogen and banned for use in cosmetics in the European Union. It can be found in both personal care items and products like lawn treatments and degreasers. She explained that even though each product might have a small amount of DEA, someone’s cumulative exposure from multiple products could be high.
Formaldehyde is another listed carcinogen the study found in use throughout many categories of personal care items and cleaners, Kristin Knox, staff scientist at the Silent Spring Institute and study author, told EHN.
Eighteen chemicals stood out to the researchers as high priorities for elimination and reformulation. “Prioritization is hard, the authors have provided valuable information for regulatory agencies to act on,” Carol Kwiatkowski, science and policy senior associate at the Green Science Policy Institute, who is unaffiliated with the study, told EHN in an email. Seeing the enormity of hazardous chemicals used in product categories like personal care calls their use into question, she said.
“There are so many safer alternatives readily available.”Industry is resistant to change, but the study emphasizes a public health need to regulate and reformulate non-essential uses of harmful chemicals, explained Polsky. “[Reformulation] just requires enough public scrutiny and regulatory pressure to do the science and to be willing to pay the additional cost,” she said.
Exposures to toxic chemicals don’t fall evenly on the population, the study points out. People who work as janitors, nail technicians, auto mechanics, hairdressers and more face high workplace exposures to chemicals they have very little control over. Products that can contain many toxics, including skin lighteners and hair relaxers, are marketed to people of color.
“This really shows the poverty of the ‘protect yourself through wise purchasing’ narrative,” said Polsky. Instead, she encourages political mobilization to address widespread exposures.
“Our study shows that these things are in vast numbers of products across vast categories that people use everyday.”
Tatum McConnell is a reporting fellow at EHN.org. Follow her on Twitter at @tatum_mcconnell.
While experts believe more data are needed to confirm the findings, this study sheds light on the possible penetration of microplastics into the human reproductive system and the urgency for understanding their potential health impact.
Led by researchers from Peking University in China, the small-scale study analyzed six testis and 30 semen samples for the presence of microplastics using two different laboratory techniques. Microplastics were detected in both human testis and semen, with the abundance in the testis significantly higher than that in semen.
The researchers found differences in the types of microplastics predominating in either testis or semen. While polystyrene, a main ingredient for plastic foams, was the most abundant polymer in the testis samples; polyethylene, which is commonly used for packaging, and polyvinyl chloride, which makes PVC pipes, were predominant in the semen. Additionally, they concluded that microplastics ranging from 20 micrometers to 100 micrometers, which is the average diameter of human hair, were the most common in testis, while those in semen had bigger sizes.
The fact that tiny plastic particles were found in human testis and semen is "no surprise", Dick Vethaak, an ecotoxicologist and emeritus professor at Vrije Universiteit in Amsterdam who has been investigating microplastics but is not involved with this study, told Environmental Health News (EHN). However, whether it is true that the larger microplastics can penetrate the male reproductive organs, as reported in this study, still presents "quite a question mark."
"It's a pilot study that, in my opinion, provides preliminary evidence that microplastics are present in human testis," Vethaak said. "But before we can draw any definite conclusions, I think we need more data."
The paper's lead authors did not respond to the interview requests by EHN.
Typically derived from plastic breakdowns or used as an ingredient in commercial products, microplastics can be as ubiquitous as plastic products are. As microplastics transverse through the global environment — from the French Pyrenees to Arctic sea ice — these particles also permeate our daily lives, with traces found in drinking water, food and air.
Previously, Vethaak and his collaborators have identified microplastics in human blood. "If it's in the blood, it can in fact go everywhere in your body," he said, adding that mounting scientific evidence has also indicated that microplastics can enter the human gut, lungs and placenta. Despite their omnipresence, the health impact of microplastics still remains unclear due to scant scientific evidence.
"I do think it's an important first step," Douglas Walker, an environmental health professor at Emory University who is not involved in this study, told EHN about the new paper. "I think [the researchers] are establishing a foundation to show that they're being detected in different types of tissues."
Walker, whose lab has been trying to develop a scalable and reliable exposure assessment method for microplastics, said the authors in this study "did take acceptable steps" to ensure the microplastics measured in the analysis were actually present in the samples versus contaminations introduced during the experiment.
"One of the challenges that we face in developing methods to measure microplastics — and one of the reasons that they are so difficult to quantify — is that microplastics are everywhere," Walker said. "If you go into a research laboratory, one of the first things you'll notice is that just about everything is plastic there."
Still, echoing Vethaak's point, Walker said the study's results on the larger microplastics can be "a little concerning," especially given that previous evidence has typically linked smaller particles to the human body uptake.
In addition, given the small sample size of this study, Walker warned against drawing conclusions on the potential health impact. "It shows the potential for microplastics to exert some effects on the male reproductive organs," he said. "What that effect is, we can't say at this point."
Shanna Swan, who is a leading reproductive epidemiologist from Icahn School of Medicine at Mount Sinai and is not involved in the study, told EHN that, at this point, scientists "can only speculate" the impact of microplastics on human health based on the chemicals that have been studied in plastics — such as phthalates and polychlorinated biphenyls (PCBs). Swan is also an adjunct scientist with Environmental Health Sciences, the publisher of EHN.
"We know a lot about what those [chemicals] do individually, but what they do in the form of a microplastic or nanoplastic, we don't know yet," said Swan, whose research helped underpin that global human sperm count and quality are declining at an alarming rate.
In addition, emerging studies in animal models, such as mice, also pointed to microplastic exposures to the potential adverse outcomes in spermatogenesis and sperm quality, hinting at the possible risk of these particles for male fertility health in mammalian organisms.
"We know testosterone levels are decreasing worldwide," she said. "Is that related to the presence of microplastics in their organs? I don't know — that is an open question."
