The studies on the effects of pesticides on shrimp and milkfish at various stages should be continued, with particular interest on uptake by food, and on the residue concentrations in the ponds.
The monitoring of pesticides in natural environments should be continued for sediments and organisms for the major tambak areas in Indonesia, in particular in connexion with the monitoring of adjacent sea and river areas from where fish fry is collected.
Research has to be stimulated for the analysis of pesticides which cannot be analysed by gas-chromatography and require different techniques. A spectrophotometer recently arrived for this purpose at the centre. The analysis of Brestan-60 (triphenyl tin acetate) is also of actual interest, but requires either polarographic or atomic absorption techniques, the costs of which would be too excessive for this purpose. Help for analysis from specialized laboratories should be sought.
Since the Jepara station is at present the only centre falling under the Ministry of agriculture and fisheries having a working unit for pesticide residue analysis, it is recommended that attention be drawn to the lack of pesticide laboratories in the various other sectors of this Ministry in Indonesia.
In this connexion, it is recommended that attention should also be given to the education of students in pesticide analysis, preferably at qualified Academic institutions in Indonesia. A good chemical background is required before taking up a course in pesticide analysis.
The use of pesticides in brackish-water ponds for killing wild-fish prior to stocking with milkfish could be avoided, when sufficient rotenone, the extract of derris-root, would be available. Some companies might be encouraged to produce artificially prepared rotenone.
Since various persistent, in particular chlorinated, pesticides are increasingly being prohibited, new pesticides are introduced on the market for which the determination of residues is sometimes impossible, thus their behaviour and persistence cannot be studied. Attention should be drawn to this problem in relation to giving permission for the applications of these pesticides.
