Review of honeybee pesticide poisoning incidents in Europe – evaluation of the hazard quotient approach for risk assessment

Background: Honeybee risk assessment is required in Europe for all pesticides where bees may be exposed. This is well established for sprayed products where the hazard quotient (HQ), calculated by dividing the application rate of the sprayed product active ingredient by the LD50, is less than 50 the product is considered safe to bees (unless it is an IGR). In the UK, Germany and the Netherlands post-registration monitoring schemes on the poisoning of honeybee by pesticides collate data on honeybee incidents. Results: The incident schemes have been invaluable in identifying agronomic practices resulting in honeybee mortality and changes have been made to labelling to address such issues. The decrease in the numbers of incidents reported supports the assertion that such schemes have positively contributed to the regulatory process and also provide confidence in the risk assessment approaches. Conclusion: This review of incidents in Europe over the last 25 years suggests that the HQ approach to risk assessment for honeybees offers an appropriate level of protection.