Chemicals previously used as inert ingredients in pesticide formulations have been detected in a wide range of North American wildlife species, according to research published in the journal Environmental Science and Technology. The compounds, perfluroalkyl phosphinic acids (PFPIAs), were widely used as anti-foaming agents in pesticide formulations until 2006, when the U.S. Environmental Protection Agency took regulatory action to cancel their use, citing “human health and environmental risks of concern.” However, the chemicals continue to be used today in consumer goods, including carpet cleaning formulas.
While scientists did not find what they would consider high concentrations of the chemicals in wildlife, the ubiquity of the detections was found to be most concerning. Researchers detected the presence of PFPIAs in the blood of 100% of animals sampled. This includes northern pike in Montreal, Canada, cormorants from the Great Lakes, and bottlenose dolphins from Sarasota Bay, Florida. “We aimed for diversity: air-breathing versus water-breathing, differences in habitat, different taxonomic groups,” Amila O. De Silva, PhD, coauthor of the study, said to CNN. Part of the reason for the wide range of detection lies with the properties of these chemicals. They are highly stable and resist degradation from exposure to water or sunlight, or breakdown by microbes. Dr. De Silva indicated to CNN that the usual ways that the environment remediates chemicals “don’t seem to apply” to PFPIAs.
“Previous work by other scientists in three separate publications have shown perfluorophosphinic acids are found in human blood samples from North America and Germany,” Dr. De Silva continued to CNN. Dr. De Silva’s previous research detected the presence of PFPIAs in 83% of household dust samples from homes sampled in Toronto, Canada.
The widespread presence of these little known persistent organic pollutants is cause for concern for regulators and the public. While limited research has been conducted to look for these compounds, even less is known about its toxicity and effects on humans, wildlife, or the wider environment. In EPA’s 2006 determination to remove these chemicals from pesticide products, the agency stated, “The very limited information available to the Agency indicates that there may be serious human health and environmental risk issues associated with these compounds.”
Despite the widespread presence of these chemicals and concern among U.S. regulators, these compounds have likely been used in pesticide formulations since the 1970s, according to Zhanyun Wang, PhD, a German scientist and expert on perfluroalkyl chemicals interviewed by CNN. This information is difficult to uncover however, because manufacturers are not required to disclose data on inert ingredients in pesticide products, despite the fact that they may be more toxic than the active ingredient in a pesticide or create hazardous synergistic interactions between it and the active ingredient or other inert ingredients.
In 2006, Beyond Pesticides and allies petitioned EPA to require manufacturers to disclose inert ingredients in pesticide product formulations. In 2009, the agency responded and took steps toward inert ingredient disclosure, publishing a proposed rule in the federal register. However, the agency took no action after proposing the rule. In 2014, the coalition filed an “undue delay” complaint against EPA, but was met with resistance. EPA backtracked on its original intent to require disclosure, and the lawsuit was thrown out because the agency indicated it would no longer issue rulemaking.
The agency instead released a list of 72 inert ingredients it had already discontinued from use in pesticide formulations. The proposal failed to address the issue of disclosure for 300 other inert ingredients allowed in pesticide formulations, but did indicate the past use of hazardous compounds, such as rotenone, turpentine oil, and cresol.
In response to this insufficient action, Beyond Pesticides and allies sued the agency again, charging that EPA’s current allowance for voluntary disclosure of inert ingredients does not protect the public or the environment. However, a federal court ruling handed down this past June stated that, “The EPA has no mandatory duty to require disclosure of “inert” ingredients in pesticides, even if those ingredients qualify as hazardous chemicals under separate statutes.”
Consumers are becoming increasingly wary of products with toxic ingredients, driving a huge shift towards ‘greener’ technologies. More and more consumers are choosing least-toxic product alternatives for pest management that are exempt from federal pesticide registration and considered minimum risk by EPA. With these products, all ingredients, including inerts, must be disclosed. This, coupled with a growing organic market, offers opportunities and challenges for formulators to develop and market least-toxic products with minimum risk pesticides that may be compatible with low hazard standards, such as organic, and consumer expectations.