I am looking forward to do my doctorate in residual effects of new chemistry insecticide, for which i am seeking a direction of new chemistry insecticides and their residual influence in directly consumable commodities and ground water reservoirs
At least in Germany those data have to be provided by the manufacturer to the legislative bodies, but they are seldom freely accessible for the interested public or critical scientists. See the example GLYPHOSAT!
Any new insecticide added for public use should have chemical information attached to it as safety data sheet. As for the residual effects I feel learning the mechanism and pharmacolgy of action of the insecticide should be important for linking and viewing its effect on the food chain. what specific organisms it targets to, what is the mechanism of action of the particular insecticide once it reaches the higher organism level and so on. I think you should read relevant papers on the specific group to which your insecticide belongs and then gather data according on particularly which animal you see the most effect on.