After 80 days, CaCl2 extracts only contained AMPA, which is consistent with the degradation pattern of glyphosate in GT oilseed rape (Nandula et al., 2007). However, NH4OH extracts contained, in addition to AMPA, significant amounts of glyphosate: from 0.8 ± 0.2% AR for washed non-GT leaves to 2.6 ± 0.2% AR for non-washed GT leaves. The absorption of glyphosate in plant material therefore provided a protection against soil degradation.