AFAIK, the Kodachrome effluent is rather similar to E6 except for the couplers present. That increases BOD and COD a bit.
As for the other comments, I'm used to Kodak bashing here on APUG and there is no surer way of ruining the company and products than undue criticism. I never said they were perfect, but they are trying hard. OTOH, perhaps the other companies products seem to hang around due to lack of R&D. Could this be true? About 30 years ago, no one complained this way when E4 products led to E6 products and etc and C-22 to C-41. Strange isn't it?