18.104.22.168. General principle
- Worker honey bees that are all aged or young emerged honey bees that are 1 to 2 days old are kept in laboratory boxes and fed with a sucrose solution for one day.
- Following this, they are exposed to a range of doses of the test substance dispersed in the sucrose solution.
- Usually mortality is recorded up to 48 h and values are used to calculate the LD50 with a regression line (see section 22.214.171.124.). Mortality can be recorded after 4 hours to look at an eventual acute effect, and is then recorded at 24 and 48 hours and compared with control values for assessment. When mortality continues to increase, the test can be extended to 72 or 96 hours. In the case of chronic oral toxicity, data are recorded up to 10 days of daily exposure with low doses.