Estimated decrease in brood production exhibited by Bombus terrestris colonies during pulsed exposure to realistic imidacloprid residues, equivalent to those previously detected in nectar of treated crops.

2013-11-04T03:44:07Z (GMT) by Ian Laycock James E. Cresswell

Reductions are relative to the number of brood produced in undosed control colonies and were obtained using the appropriate BHM best-fit dose-response relationship from Figure 2. The reduction's 95% confidence intervals, given in parentheses, were also obtained from BHMs in Figure 2.

a

Refers to the estimated decrease in brood production expected after a 14-day exposure to imidacloprid at the given dosage.

b

Refers to the estimated total decrease in brood after a 28-day pulsed exposure at the given dosage (14 days ‘on dose’, 14 days ‘off dose’).

c

Maximum imidacloprid residues detected in the nectar of oilseed rape [21]. Data originates from studies conducted only in Member States of the European Union (OSR–Europe) and from studies including North America (OSR–USA).

d

Mean maximum level of neonicotinoid residues in nectar calculated from 20 studies [56].

e

Residues in dosed syrup used in a semi-field trial conducted by Gill et al. [8].