{"id":27872,"date":"2020-10-09T00:01:01","date_gmt":"2020-10-09T04:01:01","guid":{"rendered":"http:\/\/beyondpesticides.org\/dailynewsblog\/?p=27872"},"modified":"2020-10-08T19:16:37","modified_gmt":"2020-10-08T23:16:37","slug":"new-insecticides-escalate-indiscriminate-harm-to-all-organisms","status":"publish","type":"post","link":"https:\/\/beyondpesticides.org\/dailynewsblog\/2020\/10\/new-insecticides-escalate-indiscriminate-harm-to-all-organisms\/","title":{"rendered":"New Insecticides Escalate Indiscriminate Harm to All Organisms"},"content":{"rendered":"

\"\"(Beyond Pesticides<\/em>, October 9, 2020) A new study demonstrates<\/a> that emerging \u201cnovel\u201d insecticides can cause significant, sublethal harm to beneficial organisms at typical \u201creal life\u201d exposure levels. As neonicotinoid insecticides<\/a> have come under fire for their terrible impacts on a broad variety of beneficial insects \u2014 including their major contributions to the decline of critical pollinators \u2014 more such \u201cnovel\u201d pesticides are being brought to market in response. The study results, the co-authors say,<\/a> \u201cconfirm that bans on neonicotinoid use will only protect beneficial insects if paired with significant changes to the agrochemical regulatory process. A failure to modify the regulatory process will result in a continued decline of beneficial insects and the ecosystem services on which global food production relies.\u201d Beyond Pesticides would add that the study outcome points, yet again, to the grave recklessness of the pervasive \u201caddiction\u201d to chemical pesticides in agriculture. The solution to this chemical morass is known, doable, and scalable: a transition to organic, regenerative agricultural practices<\/a> that get everyone off the \u201ctoxic treadmill.\u201d<\/p>\n

Neonicotinoid pesticides<\/a> (neonics) are the class of chemical pesticides most commonly used worldwide, both on crops and as seed treatments. They are systemic, meaning they infiltrate all tissues of a plant, and are environmentally persistent (in plants and in soils); they can also contaminate freshwater sources. As the study paper notes<\/a>, \u201cField-realistic applications of neonicotinoids can have significant sub-lethal impacts on beneficial insects, with knock-on effects on ecosystem services. This has resulted in bans and restriction on neonicotinoid use globally, most notably in the European Union.\u201d Here in the states, the Environmental Protection Agency (EPA) has permitted broad use of neonics, and is currently reviewing<\/a> all neonicotinoid pesticides. This study addresses the substance of one of Beyond Pesticides\u2019 critiques of EPA\u2019s regulatory failures on neonics: the\u00a0insufficiency of the agency\u2019s risk assessment procedures in accounting for sublethal impacts of the compounds.<\/p>\n

The study\u2019s researchers discovered that two novel pesticides, flupyradifurone<\/a> and sulfoxaflor<\/a>, share the same mode of action as neonics, although they are (nominally) from different chemical classes than are neonics. This research focused on these two compounds because, given that both Dow Agrochemicals\u2019 sulfoxaflor (classified as a butanolide) and Bayer CropScience\u2019s flupyradifurone (classified as a sulfoximine) are somewhat effective on pest species that resist neonics, these novel insecticides are considered to be candidates to replace neonics in geographic regions with significant levels of neonic resistance, and where neonic compounds are restricted or banned.<\/p>\n

Sulfoxaflor and flupyradifurone, like neonics, are systemic insecticides. Flupyradifurone can persist in soils for months or years, whereas sulfoxaflor\u2019s half-life in soil is two or three days. Research data reviewed by the subject study<\/a> suggest that beneficial insects will be exposed to these compounds at relatively high concentrations in agricultural environments. This can happen during spray applications to seeds or fields, or indirectly, when insects (or birds or other organisms) feed on such seeds<\/a>, as well as on plant tissue, pollen, or nectar.<\/p>\n

The research was conducted by Harry Siviter, PhD and Felicity Muth, PhD of the Department of Integrative Biology at the University of Texas at Austin; the subsequent paper was published by the Proceedings of the Royal Society B: Biological Sciences<\/em><\/a> in late September, 2020. The researchers\u2019 meta-analysis extracted useful data from 19 of the 26 studies they reviewed, and paid particular attention to impacts on beneficial insects \u2014 dominantly, on bee species \u2014 and evaluated outcomes related to organism mortality, reproduction, and behavior. In addition, the scientists evaluated impacts on predator species, such as such as wasps, lacewings, and beetles.<\/p>\n

The researchers learned that flupyradifurone can have lethal impacts at field-realistic levels, with some kinds of bees being more vulnerable than others; further, and unsurprisingly, exposures to the compound were more likely to be harmful in combination with other environmental stressors, such as poor nutrition, pathogens, or other agricultural chemicals.\u00a0The co-authors note that the lethality of sulfoxaflor, which is toxic to bees at high levels of exposure, may vary at lower doses, depending on the interactions with other environmental factors. But given certain combinations of those variables, sulfoxaflor exposures at field-realistic levels appear to increase bee mortality.<\/p>\n

The study also shows<\/a> that sulfoxaflor has negative impacts on bee reproduction similar to those of neonics, particularly reduced reproduction (egg laying) and poor larval development, and that flupyradifurone exposures impair bees\u2019 flight behavior, foraging success, and bodily temperature regulation. Findings included impacts on beneficial predators, including a huge increase (40\u201360%) in the mortality of flupyradifurone-exposed rove beetles, and 100% mortality of exposed insidious flower bugs (also known as pirate beetles).<\/p>\n

Sulfoxaflor shows harmful effects on many taxa: hymenoptera (bees, wasps, ants), coleoptera (beetles), and hemiptera (cicadas, aphids, planthoppers, leafhoppers). At field-realistic exposure levels, for example, the parasitic activity of some wasps was reduced, and mortality increased; lacewings showed increased mortality and reduced fertility; ladybug larvae suffered 100% mortality; and pirate beetle mortality was 96% within 24 hours of exposure to sufoxaflor.<\/p>\n

Both compounds, which act on the nervous systems of organisms<\/a>, have been registered for use throughout the European Union (EU), where use of neonics is significantly constrained. EPA first registered sulfoxaflor in 2013, and amended the registration in 2016 to create some limitations on its use. In 2015 it issued a cancellation order<\/a> for all uses of sulfoxaflor, but then granted some emergency exemptions for its use. In 2019, EPA effectively restored all previously registered uses, functionally \u201ccanceling the cancellation,\u201d and even expanded uses<\/a> of the chemical insecticide.<\/p>\n

EPA registered flupyradifurone<\/a> for use in 2015, after which the Pesticide Research Institute commented<\/a>, \u201cDespite the safety claims in the registration notice, the available data suggest that flupyradifurone may possess many of the undesirable attributes associated with neonicotinoids.\u201d Indeed, in June 2020, Beyond Pesticides wrote<\/a> about outcomes of an Oregon State University study that showed that both \u201csulfoxaflor and flupyradifurone . . . were found to increase apoptosis (cell death) and increase oxidative stress in exposed honey bees. The study . . . [paper writes], \u2018With the recent Environmental Protection Agency (EPA) approval for use of both flupyradifurone and sulfoxaflor, and with the growing concern regarding pollinator health, it is important to better understand any potential negative impacts (especially sub-lethal) of these pesticides on bees.\u2019 However, this statement begs the question \u2018why [were] these two new bee-toxic pesticides . . . approved by EPA in the first place.\u2019\u201d<\/p>\n

The authors conclude:<\/a> \u201cNovel insecticides have significant sublethal impacts on beneficial insects, demonstrating that, in its current form, the regulatory process does not safeguard beneficial insects from detrimental effects of agrochemical use. Thus, simply replacing neonicotinoids with novel chemical insecticides is unlikely to reduce negative consequences on beneficial insects.\u201d In their paper, the researchers make several recommendations EPA should include in its regulation of pesticides:
\n\u2022 mandatory assessments of sublethal effects on wild bees<\/p>\n