Kevin Hackwell, Group Manager Campaigns and Advocacy, Forest and Bird, Trustee, Pest Control Education Trust
Morning Report did an interview with Paul Tucker (9 October) where he raised concerns about low concentrations of 1080 in the water supply could have endocrine disruptor effects.
Endocrine disruptors (EDs) are chemicals which interfere with hormonal or endocrine systems and can have (or are widely thought to have) nasty adverse effects at extremely low doses; and at much lower doses than those for which 1080 is known to cause harmful, but non-lethal, effects.
Morning Report did an interview with Paul Tucker (9 October) where he raised concerns about low concentrations of 1080 in the water supply could have endocrine disruptor effects.
Endocrine disruptors (EDs) are chemicals which interfere with hormonal or endocrine systems and can have (or are widely thought to have) nasty adverse effects at extremely low doses; and at much lower doses than those for which 1080 is known to cause harmful, but non-lethal, effects.
The possibility that 1080 might be an ED was raised in a paper published in 2003. What the paper basically says is that 1080 can have toxic effects on reproductive systems (as it does on other systems); therefore 1080 might be an endocrine disruptor and this possibility should be further studied. However, ever since this paper claims have been made that 1080 is a “known” or “proven” endocrine disruptor.
This was speculation not science, but in response the then Animal Health Board (and interestingly also the NZ Deerstalkers Association) funded a suite of studies to investigate this risk and they found that 1080 does not show the properties of an ED. The known sub-lethal reproductive effects of 1080 are associated with the normally accepted mode of action (blocked supply of energy to cells) which occurs at much higher doses than the vanishingly small levels which have been linked to endocrine disruptor effects.
This detailed work was published in 2004 and 2005 (Tremblay, et al 2004. Australasian Journal of Ecotoxicology 10: 77-83, and Tremblay, et al 2005. Australasian Journal of Ecotoxicology 11: 155-162) nearly a decade after the OECD report.
In short there is no proof, or even any scientific evidence, that 1080 is an endocrine disruptor; in fact the available (and comprehensive ) evidence is that it does not belong to this class of chemicals.
But arguments about whether it is or isn’t an endocrine disruptor aside, there is still the very real issue of the possible impacts of minute quantities of 1080 in water supplies.
Many people are understandably worried about the possibility of 1080 getting into water supplies after control operations – which is why the Ministry of Health sets a limit of 2 parts per billion of fluoro-acetate (the active ingredient of 1080) that can be allowed in a water supply after an operation. Over the past couple of decades thousands of samples have been taken for the Ministry of Health after operations and that limit has never been exceeded in a water supply.
But how ‘cautious’ is that 2ppb fluoro-acetate limit ?
To put the limit into some sort of understandable context it is interesting that an average cup of ordinary black tea naturally has concentrations of fluoro-acetate of 5-6 parts per billion. The camellia plant that we get tea from grows in high fluoride soils in Sri lanka and India and produces its own “1080” – (fluoro acetate).
As you might appreciate from this example the exposure to fluoro-acetate (1080) that the vast majority of Aucklanders will ever experience is likely to be self administered in very low doses on a regular basis (often several times a day) when they drink tea.
This is not to make light of the fact that 1080 is a deadly and effective mammalian poison (which is why it is carefully used against introduced mammalian predators). What this example is attempting to do is put the understandable concerns about its possible presence in water supplies, into a context that might be easier to comprehend.
This was speculation not science, but in response the then Animal Health Board (and interestingly also the NZ Deerstalkers Association) funded a suite of studies to investigate this risk and they found that 1080 does not show the properties of an ED. The known sub-lethal reproductive effects of 1080 are associated with the normally accepted mode of action (blocked supply of energy to cells) which occurs at much higher doses than the vanishingly small levels which have been linked to endocrine disruptor effects.
This detailed work was published in 2004 and 2005 (Tremblay, et al 2004. Australasian Journal of Ecotoxicology 10: 77-83, and Tremblay, et al 2005. Australasian Journal of Ecotoxicology 11: 155-162) nearly a decade after the OECD report.
In short there is no proof, or even any scientific evidence, that 1080 is an endocrine disruptor; in fact the available (and comprehensive ) evidence is that it does not belong to this class of chemicals.
But arguments about whether it is or isn’t an endocrine disruptor aside, there is still the very real issue of the possible impacts of minute quantities of 1080 in water supplies.
Many people are understandably worried about the possibility of 1080 getting into water supplies after control operations – which is why the Ministry of Health sets a limit of 2 parts per billion of fluoro-acetate (the active ingredient of 1080) that can be allowed in a water supply after an operation. Over the past couple of decades thousands of samples have been taken for the Ministry of Health after operations and that limit has never been exceeded in a water supply.
But how ‘cautious’ is that 2ppb fluoro-acetate limit ?
To put the limit into some sort of understandable context it is interesting that an average cup of ordinary black tea naturally has concentrations of fluoro-acetate of 5-6 parts per billion. The camellia plant that we get tea from grows in high fluoride soils in Sri lanka and India and produces its own “1080” – (fluoro acetate).
As you might appreciate from this example the exposure to fluoro-acetate (1080) that the vast majority of Aucklanders will ever experience is likely to be self administered in very low doses on a regular basis (often several times a day) when they drink tea.
This is not to make light of the fact that 1080 is a deadly and effective mammalian poison (which is why it is carefully used against introduced mammalian predators). What this example is attempting to do is put the understandable concerns about its possible presence in water supplies, into a context that might be easier to comprehend.
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