(Beyond Pesticides, July 6, 2017) The Washington State Department of Ecology (Ecology) is evaluating a new permit application for the use of imidacloprid, a toxic neonicotinoid, to combat a growing native population of burrowing shrimp that threatens oyster beds in Willapa Bay and Grays Harbor in Washington state. The application was recently submitted to Ecology by a group of oyster farmers from the Willapa Grays Harbor Oyster Growers Association (WGHOGA), who “propose to use the pesticide to treat tide lands to support their aquaculture practices.” Imidacloprid is known to be toxic to bees and aquatic organisms, raising questions on the impacts of its use on the long-term ecological health of the bays.
In April 2015, much to the dismay of activists and concerned local residents, Ecology approved a permit submitted by oyster farmers for the use of imidacloprid to combat burrowing shrimp in these aquatic ecosystems. But with a nationwide public outcry, the permit was withdrawn in May 2015. The recent request that was submitted differs in several ways from this 2015 permit, including:
- The new permit proposes treating 485 acres in Willapa Bay and 15 acres in Grays Harbor, compared to 2,000 acres combined from both water bodies in the 2015 permit.
- The oyster farmers propose applying imidacloprid from boats or ground equipment rather than aerially in helicopters.
- The 2017 Preliminary Aquatic Risk Assessment for Imidacloprid by the U.S. Environmental Protection Agency (EPA) and similar risk assessments adds new research to the supplemental environmental review being drafted by Ecology.
In its 2017 risk assessment, EPA finds risks from imidacloprid exposure to ecologically important organisms not previously evaluated as part of its regulatory review. A 2013 comprehensive assessment of the effects of imidacloprid in surface water reports a wide variety of aquatic invertebrates adversely harmed by imidacloprid residues in water. These important findings, as well as others, will need to be considered as Ecology undertakes its environmental review process for this aquatic pesticide permit.
The shellfish industry is important to the Pacific Northwest, injecting an estimated $270 million or more into the region’s economy, and providing jobs for many. Washington’s tidelands, especially those in Willapa Bay. The fisheries have been particularly productive for more than 100 years. However, according to shellfish growers, the burrowing shrimp undermines the industry. The creatures burrow into shellfish beds, making the beds too soft for shellfish cultivation. Their burrowing churns the tidelands into a sticky muck, smothering the oysters. After several years of deliberations and studies, Ecology identified imidacloprid as its preferred choice for eradicating the shrimp. According to the agency, imidacloprid disrupts the burrowing shrimps’ ability to maintain their burrows. A 2013 risk assessment conducted by Ecology concluded that, “The proposed use of imidacloprid to treat burrowing shrimp in shellfish beds located in Willapa Bay and Grays Harbor is expected to have little or no impact on the local estuarine and marine species”, and will not significantly impact human health.”
However, in comments submitted by the Xerces Society in 2014, supported by Beyond Pesticides and others, Ecology failed to consider existing published research that demonstrates the potential for wide-range ecological damage from the use of the insecticide imidacloprid. The groups say that the risks, coupled with the lack of data on how imidacloprid will impact sensitive marine environments like Willapa Bay and Grays Harbor, warrant greater caution. The comments urged the agency to review existing data that shows imidacloprid’s potential to damage the rich marine ecosystems of Willapa Bay and Grays Harbor. Imidacloprid is water soluble and highly toxic to aquatic invertebrates. Its persistence and largely irreversible mode of action in invertebrates make it particularly dangerous in these ecosystems. Further, the comments note, imidacloprid’s impact on these key species can also cause a cascading trophic effect, harming the fish, birds, and other organisms that rely on them for sustenance.
The decision to withdraw the permit in May 2015 was reached in large part due to vocal public outrage over the plan, as consumers, environmental organizations, and prominent local chefs spoke out against the spraying. Retailers, consumers and environmental organizations were not the only ones to raise concern for the use of imidacloprid. The National Oceanic and Atmospheric Administration’s National Marine Fisheries Service (NMFS) voiced many concerns over the application of imidacloprid to the bays.
Beyond Pesticides recently released Poisoned Waterways, a report which documents the persistence of neonicotinoids in U.S. waterbodies and the danger they cause to aquatic organisms, resulting in complex cascading impacts on the aquatic food web. The report also highlights current regulatory failures of EPA aquatic standards, which continue to underestimate risks to sensitive species due to a reliance on test protocols that do not reflect real-world exposures or susceptibilities. Further, the impacts of chemical mixtures and synergistic interactions are not considered. Aquatic standards, which continue to underestimate risks to sensitive species due to a reliance on test protocols that do not reflect real-world exposures or susceptibilities. Further, the impacts of chemical mixtures and synergistic interactions are not considered.
Once the Washington State Department of Ecology finalizes their draft Supplemental Environmental Impact Statement (SEIS), a 45-day public comment period will open. However, if you have information you want considered now as they complete this SEIS, Ecology encourages you to send it to Derek Rockett, Water Quality Program Permit Writer, at firstname.lastname@example.org.
Sources: WA State Department of Ecology
All unattributed positions and opinions in this piece are those of Beyond Pesticides.