butyltin (ΣBT = MBT + DBT + TBT) concentration in the
female tissues across stations, whilst DBT corresponded to
35–45 % and MBT to 20–25 %. The butyltin degradation
index (BDI) (Díez et al. 2002), which gives the proportion of
TBT in relation to its metabolites through the formula BDI =
(MBT + DBT) / TBT, was 1.3 (Stn 3), 1.9 (Stn 4), 2.2 (Stn 5)
and 1.8 (Stn 6).