Bob,
If beekeeper(s) find dead bees (colonies) and then have pesticide 
amounts verified - which data do they then relate to?

Accepted LD. levels change over time as more investigation occurs.

Is it possible to back claim if losses occur at for eg. 20ppb but 
accepted knowledge indicated the lethal dose  at 200ppb - which is then 
reduced after a period of time to 10ppb ?

The sub lethal effects - if bees are not dying "en masse" after one 
exposure - but indicate problems (behavioural or other) leading to 
eventual death or limitation resulting in financial loss to the 
beekeeper - Is a partial payment due from the party causing such, with 
the remaining fraction being the responsibility of "X"?

With "Innocent till proven guilty" being a most demanding procedure to 
deal with - Who provides data accepted by all parties! - Self supplied 
data from protocols that are not necessarily covering questions that 
beekeepers ask do not lead to amicable resolutions.

Regards,

Peter

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