The followin quote is from a Canadian PMRA (pesticide management
 regulatory agency) information officer:

>MRL (maximum residue limits) pertain to the human health risk assessment
>and are not determined by, nor impact on, the environmental risk
>assessment. MRLs are established under the Food and Drug Regulations (FDR)
>of the Food and Drugs Act (FDA) only if Health Canada's PMRA has determined
>that the consumption of the pesticide residues that could remain on the
>food as it is eaten will not pose an unacceptable human health risk.
>Following review of the minor use proposals for the use expansion of
>imidacloprid to corn (field and sweet) and eggplant, MRLs of 0.08 ppm for
>eggplant and 0.05 ppm for corn (field and sweet) were recommended.
>Accordingly, Table II of the Food and Drug Regulations was amended to
>include these MRLs (1367-imidacloprid). No other changes were made to the
>table.

So, it is allowable to have 50 ppb imidacloprid residue in corn.  This is 
above the LD50 (lethal dose to 50% of the test subjects) for bees .  I wonder
whether or not imidacloprid is destroyed in the making of corn syrup?  

Stan

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