I think when people are talking about fertilizer its not just chicken pellets but all sorts. Any thing that is found in the wild thats natural. I think fish, blood, bones, seaweed etc are used and would certainly be organic and would be an issue because of mercury. I eat organic myself though, I just think its the best you can get at the moment without growing it yourself and the levels cannot be that high. I have gotten much better and have eaten this way. Only other choice is grow your own but don't but organic compost because who knows where that is from......