I can’t say Dursban is safe or suitable for cannabis, and that’s even if I was not an organic farmer. Shits nasty. Next time, don’t spray insecticide or anything that ends in -cide. You have a world of other solutions. I’ve never drawn a correlation between pests and yellow leaves. That’s normally N related. You can simultaneously experience a pest issue but the two are unrelated.
Safe, nontoxic solutions include Diatomaceous earth (powder you top dress soil and apply to leaves before flower), ladybugs (beneficial predator), among others. Both are Che-, non toxic, and good for the earth. Your growing something you’re going to eventually smoke, I assume.
Good luck