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gavin
07-04-2010, 05:52 PM
Hi Eric and All

Welcome to the forum Eric. I see that you are raising pesticide issues in your blog. Let's move the discussion to here, as folk are more likely to reply in the main forum area.

I replied to an email of yours recently where I suggested that you read the pesticide work you were intending to quote. Did you see the paper? Here is my take on it:

- yes, pesticide residues in the general environment are worrysome

- American commercial beekeepers may be exposed to more than beekeepers in the UK

- the top three pesticides (fluvalinate, coumaphos, chlorpyrifos) were probably all put there by the beekeepers

- the levels of fluvalinate were truly shocking, >90% of samples with fluvalinate and an average detection level of 50% of the LD50 value in the wax samples, despite this pesticide being unpopular now with beekeepers as it no longer does the job (on mites). It has been mentioned elsewhere that sheep dip was used extensively.

- the levels of coumaphos were also worrying (illegal in the UK, legal in the US)

- chlorpyrifos is poured around hives to control fire ants on the advice of the USDA (not something I've ever had the need to do, and I doubt that I'd be allowed to thank goodness)

- the next on the list was a fungicide, and there is a paper from Penn State that says this pesticide *might* have a role in CCD.

The paper Eric was discussing:

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0009754

(Table 5 has summaries along with the LD50 values)

The levels and the frequency of detection of neonicotinoids were low in that study, but there is work elsewhere that shows that they may be more common in France.

My point is essentially that the story from that work is that the beekeeping industry in the US needs to clean up its own act. This isn't the tone of some of the discussion I've seen of this paper.

best wishes

Gavin