DRUG ACCUMULATION AND ELIMINATION IN CALLIPHORA-VICINA LARVAE

Calliphora vicina larvae were fed on drug-laden muscle from three suic ides involving amitriptyline, temazepam and a combination of trazodone and trimipramine; triplicate daily harvestings were analysed. The lim it of detection for all four drugs was 0.01 mu g drug/g larvae. Mean d rug concentrations (mu g/g) in the initial muscle were: amitriptyline, 2.68; temazepam, 4.04; trazodone, 21.56; and trimipramine, 19.58. Lar val rearings for days 4-8 (15 larval samples per drug) had mean and ra nges of drug concentrations (mu g/g) of 0.10 (r, 0.02-0.24) for amitri ptyline; 0.52 (r, 0.26-0.78) for temazepam; 0.13 (r, 0.05-0.32) for tr azodone; and 0.28 (r, 0.10-0.59) for trimipramine. After day 8 there w as a precipitous fall in larval drug concentrations associated with pu pariation. At day 11 ranges of drug concentrations (mu g/g) were: amit riptyline, < 0.01-0.01; temazepam, 0.01-0.08; trazodone, < 0.01-0.01; and trimipramine, 0.04-0.04. Day 16 pupae had corresponding ranges (mu g/g) of < 0.01, < 0.01-0.01, < 0.01 and < 0.01-0.02. Transfer to drug -free food at day 5 led to similar falls in drug concentrations (mu g/ g) from day 5 to day 6: 0.08-0.03 for amitriptyline, 0.61-0.09 for tem azepam, 0.13-0.01 for trazodone, and 0.30-0.02 for trimipramine. The r esults show considerable variation in larval drug concentrations, both at the same developmental stage and at different stages of the life c ycle, under conditions which closely reflect case situations. In pract ice, the precipitous decrease in drug concentrations in non-feeding la rvae and at pupariation make it desirable to sample only larvae active ly feeding on a corpse.