Approximately 20 DDT analogues are being evaluated for utility in vector control programs and for other pest control uses as persistent yet biodegradable substitutes for DDT. From residual activity tests and evaluation in plywood huts two compounds OMS-1406, CH3C6H4CHCCl3C6H4OCH3 and OMS-1476, CH3C6H4CHCCl3C6H4OC2H5 appear to have the most favorable combination of properties. These compounds are much less acutely toxic to mammals and fish than DDT, persist for long periods on plywood, are highly biodegradable and of low environmental persistence, and are residually effective against Anopheles and Culex mosquitoes. Preliminary data suggests they can be manufactured at costs approaching that of DDT. Additional studies are being conducted on the biodegradability of DDT analogues with altered aliphatic groups.
