Further Scientific Opposition to Imidacloprid Use in Salmon Farming

Since Scottish Salmon Watch broke the shocking news in March that Benchmark's secret BMK08 lice treatment is actually the toxic neonicotinoid insecticide Imidacloprid (banned for use in terrestrial agriculture in 2018), scientific opposition has been building.

The Sunday Times reported today (14 June 2020):

Earlier this week, Scottish Salmon Watch solicited scientific support for a ban on the use of Imidacloprid in salmon farming and shared a scientific dossier - "Imidacloprid - A Neonicotinoid Insecticide Toxic to Aquatic Life" - detailing environmental impacts of Imidacloprid on aquatic ecosystems.

Here's some feedback from the scientific community:

From: Francisco Sanchez-Bayo <[email protected]>
Date: Tue, Jun 9, 2020 at 9:54 AM
Subject: Re: Imidacloprid - scientific research into aquatic impacts?
To: Don Staniford <[email protected]>

Dear Don,

Excellent compilation!

You can add our recent paper on the time-cumulative effects of neonicotinoids on aquatic and terrestrial arthropods:

See link at https://doi.org/10.3390/ijerph17051629

From: Francisco Sanchez-Bayo <[email protected]>
Date: Wed, Jun 10, 2020 at 8:34 AM
Subject: Re: Imidacloprid - scientific research into aquatic impacts?
To: Don Staniford <[email protected]>

Dear Don,

Imidacloprid is extremely toxic to invertebrates by acute and chronic exposure, and therefore makes no sense at all to use it in the aquatic environment, where organisms are exposed continuously to residues, no matter how low they may be.

The claim that imidacloprid would not enter the aquatic environment upon release of the salmon is fallacious. Due to the mobility of this chemical in water, it is practically impossible to avoid contamination of the receiving waters. Even tiny residues below 1 ppb can deplete populations of aquatic insects! For this reason, I cannot understand the need for using a product that contains imidacloprid for salmon farming. There are other chemicals used for disinfecting fish that cause less harm to the aquatic environment than imidacloprid, so why should anyone insist in using the worst chemical in the market for such a purpose?

Best regards

Francisco Sánchez-Bayo, PhD

Honorary Associate

School of Life and Environmental Sciences | The University of Sydney

currently: Department of Environment and Energy | Canberra

https://www.researchgate.net/profile/Francisco_Sanchez-Bayo2

From: Francisco Sanchez-Bayo <[email protected]>
Date: Mon, Jun 29, 2020 at 9:31 AM
Subject: Re: Imidacloprid patent - new information on use in salmon farming
To: Don Staniford <[email protected]>

Dear Don,

That would be a disaster!

Please find attached a copy of a paper that was published 15 years ago, showing that imidacloprid does not help get rid of ectoparasites such as sea lice but on the contrary, it encourages the parasites' attack on fish.

I wish you luck in your campaign to prevent this ecological atrocity.

Regards

Francisco Sánchez-Bayo, PhD

Honorary Associate

School of Life and Environmental Sciences | The University of Sydney

currently: Department of Agriculture, Water and Environment | Canberra

https://www.researchgate.net/profile/Francisco_Sanchez-Bayo2

From: Ryan Prosser <[email protected]>
Date: Tue, Jun 9, 2020 at 1:27 AM
Subject: Re: Imidacloprid - scientific research into aquatic impacts?
To: Don Staniford <[email protected]>

Don,

Thank you for reaching out. My research group has conducted research on the toxicity of imidacloprid on freshwater invertebrates. It is relatively toxic to freshwater invertebrates, particularly freshwater insects (e.g., larval midges, larval mayflies). It’s toxicity to vertebrates (e.g., fish) is relatively low. The Pest Management Regulatory Agency (PMRA; agency responsible for registering pesticides for use in Canada) has reduced the uses of imidacloprid due to high risks to pollinators.

I would be concerned about the release of imidacloprid into aquatic systems. It may not cause direct toxicity to fish but it will likely have an adverse effect on invertebrate populations, which will likely result in indirect effects on non-invertebrate populations and be detrimental to the ecosystem. I haven’t read deeply into BMK08/Ectosan/D10 Aqua Blast but the couple articles I read from your dossier indicated that the fish are passed through a bath that contains imidacloprid. The big question would be how much of the imidacloprid is being released back into the aquatic ecosystem in which the fish are being reared? Risk is a function of toxicity and exposure, so we know that imidacloprid can be relatively toxic to invertebrates, so the important question is the frequency and level of exposure.

Again, thank you for reaching out. This would make for a very interesting ecological risk assessment.

Kind regards,

Ryan Prosser

Assistant Professor – Environmental Toxicology

School of Environmental Sciences

University of Guelph

https://ses.uoguelph.ca/people/ryan-prosser

From: Whitehorn, Penelope(IMK) <[email protected]>
Date: Mon, Jun 8, 2020 at 6:40 PM
Subject: RE: Imidacloprid use in salmon farming in Scotland - concerns?
To: Don Staniford <[email protected]>

Hi Don,

Yes sure:

"It is extremely worrying that imidacloprid is being considered for use in salmon farming. This neurotoxin is known to cause harm to a wide range of non-target species and I’m yet to see any convincing evidence that it is safe or appropriate to use in an aquatic environment."

Hope that helps!

Best wishes,

Penelope

https://www.imk-ifu.kit.edu/staff_Penelope_Whitehorn.php

From: Jean-Marc Bonmatin <[email protected]>
Date: Mon, Jun 8, 2020 at 6:00 PM
Subject: Re: Imidacloprid - scientific research into aquatic impacts?
To: Don Staniford <[email protected]>, MBVL <[email protected]>

Dear Don,

Thank you for your e-mail and the quality of your dossier below (your link).

I think that the use of imidacloprid as it is presented for salmon farming, will be catastrophic for aquatic invertebrates and even for fishes.

I am not sure that EU regulations still apply to Scotland because of Brexit (EU banned imidacloprid, except for greenhouses).

I send your demand to our specialists within our IUCN Task Force on Systemic Pesticides (www.tfsp.info), and I will let you know in case they identify some new information on this topic that could be useful for you

Best regards,

JMB

Dr BONMATIN Jean-Marc, Research scientist

Centre National de la Recherche Scientifique (CNRS)

Centre de Biophysique Moléculaire, 45071 Orléans, France

Internet link

Here's some scientific papers referenced via "Imidacloprid - A Neonicotinoid Insecticide Toxic to Aquatic Life":

Scientific References:

The new aspects of using some safe feed additives on alleviated imidacloprid toxicity in farmed fish: a review. Reviews in Aquaculture, April 2020

Insecticide exposure during brood or early-adult development reduces brain growth and impairs adult learning in bumblebees. Proceedings of the Royal Society B, March 2020

Coral Reef Organisms: Differential Sensitivities to an Agricultural Pesticide. Ocean Sciences, February 2020

Environmental pollution from pet parasiticides. Veterinary Record, January 2020