From the source I have given: > A recent study compared the effectiveness of a rotenone-pyrethrin mixture versus a synthetic pesticide, imidan. Rotenone and py

From the source I have given: > A recent study compared the effectiveness of a rotenone-pyrethrin mixture versus a synthetic pesticide, imidan. Rotenone and pyrethrin are two common organic pesticides; imidan is considered a "soft" synthetic pesticide (i.e., designed to have a brief lifetime after application, and other traits that minimize unwanted effects). It was found that up to 7 applications of the rotenone- pyrethrin mixture were required to obtain the level of protection provided by 2 applications of imidan. > It seems unlikely that 7 applications of rotenone and pyrethrin are really better for the environment than 2 applications of imidan, especially when rotenone is extremely toxic to fish and other aquatic life. I know it is anecdotal evidence, but organic farmers would not care if the fertilizer/pesticide made from mined minerals are better/worse for the environment or not as long as it passes the "organic" criteria. A rather more useful criteria IMO would be "relatively harmless to the environment"