Current experimental advances from the French Methodological Bee Group. New improvement for future repro-toxicity tests.

Repro-toxicity tests reveals a new approach in the assessments of effects to honeybees with the particularity to present a mid-term evaluation and an undirect exposure of individual honeybees. This article follows a previous one since the improvement has not progressed during the pandemic. The French Methodological Bee Group is committed to provide guidance and protocols to assessors about local or international methodologies. In this working group, public and private researchers work together with beekeepers, industrials and CRO’s in the aim of providing adapted protocols to the honeybee. Laboratory LD50 tests and Semi-Field experiments were set up during the 70s’ and review regularly under reference CEB 230, while new guidelines were initiated because of needs for new assessments. The Brood test in laboratory conditions (Inra 2005), the chronic toxicity over ten-days (Itsap 2009) and the homing flight test (ITSAP 2011) were initiated before being extend at OECD level (in 2016, 2017 and 2021 respectively). The behavior of forager honeybees under tunnels as well as the measurement of HPGs (Hypopharyngeal glands) are still under French CEB230 methodology only. Over the short-term effects in laboratory and mid-term effects in field or semi-field, the professional beekeeper organization requires for long-term effects of phytopharmaceuticals on colony development. It is also a requirement from the EFSA guidance document. In this aim it was discussed to apprehend the lifespan of bees, drones, and queens. As it is a too large investment for a single methodology, we now focus on the drone fertility for a first step. Later on the lifespan of forager honeybees would be checked as a hypothesis of the decrease of the honey production if it is reduced by several days. Moreover, the duration of queens will induce multiyear observations and difficulties to run under GLP. As the repro-toxicity concept could cover the fertility, the fecundity, and the prolificacy of the queen in the colony, it has been selected at this stage to consider the drone fertility only.