I just read this: Abstract Results are presented that explore the possibility of organocyanide compounds in wastewater contributing to elevated cyanide levels in the chlorinated effluents of publicly owned treatment works. Four model compounds, acetonitrile, amygdalin, cyanocobalamin, and 2-acetoxy-3-butenenitrile, were selected and tested with varying chlorine dosages for release of cyanide by total and diffusible cyanide procedures. The coenzyme form of vitamin B12, which does not contain cyanide, was also tested. It was found that acetonitrile and amygdalin do not yield cyanide with or without chlorination, cyanocobalamin had increased release with increased chlorine dosages, and 2-acetoxy-3-butenenitrile had generally decreased release of cyanide with increased chlorine dosages. Both cyanocobalamin and coenzyme vitamin B12 gave evidence of the formation of the cobalt-cyanide complex after chlorination, even though the molecular structure of the coenzyme vitamin B12 contains no cyanide. from: https://www.ncbi.nlm.nih.gov/pubmed/11995867 and have downloaded the full article for study. My water is chlorinated. I have recently been filling up buckets of it and letting it air out over a day or so. I do not know how much chlorine is reduced, but I do know the water does taste better. Do you de-chlorinate your water? How about de-flourinate it? I have heard of methods (such as using terracotta pots to get rid of the fluoride as well, but don't know enough about it. Besides the fact that chlorine kills the B12 producing bacteria, it sure seems like another good argument for only drinking/washing your vegetables in water that is free from chlorine.