Bromadiolone
The studies show that bromadiolone is relatively quickly degraded in soil under aerobic conditions in laboratory with calculated DT50 values between 2 and 28 days (at 20°C). Normalised to soil moisture at field capacity the mean DT50 was 7 days for bromadiolone. The degradation follows a biphasic pattern with decreasing degradation rate with time. DT90 was estimated to be between 14 and 585 days (at 20°C) with a mean value of 201 days. Degradation of bromadiolone led to the formation of five major metabolites, which were present in significant quantities (exceeding 10 % of AR). One of the metabolites was identified as bromadiolone ketone with an estimated half-life between 86 and 252 days at 20°C. The four remaining metabolites (Unk 1, Unk 3, M4 and M5) were not identified but their half-lives were estimated. DT50 varied between 46 and 206 days at 20°C. For one of the metabolites (Unk 3) it was not possible to calculate a DT50 since a decline profile was not established during the study. At least six other minor metabolites were formed at levels not exceeding 10 % of AR. The degradation rate of metabolites was in general investigated in only one study (for the ketone metabolite two degradation rates were available). No degradation rate for the metabolite M3 was calculated even though it was observed in >10 % of AR at two sampling dates. The data indicated that the ketone metabolite, the unknown 1 and unknown 3 may have degradation times exceeding the degradation trigger in Annex VI (DT50 > 3 months or DT90>1 year). However, due to the limited environmental exposure and hence limited accumulation of these metabolites it is proposed that this is acceptable and no further data required. This may however need to be discussed at experts meetings.The amount of carbon dioxide that was formed steadily increased to between 2 and 23 % of AR in the test soils after ca 100 days. The level of soil non-extractable residues (NER) reached a level of 9 to 21 % of AR after ca 100 days. The levels where however increasing steadily during the studies and therefore it cannot be excluded that the amount of soil NER would be even higher at a later time.