The article I quoted which seemed to be rather obscurely written was investigating whether the cyanide was broken by hydrolysis into ammonia etc, and came to the conclusion that this was too slow a process to account for the observed removal of cyanide. Anyway, i see that a metal finishing company, Anochrome, has now held its hand up and accepted responsibility.
Rather that there was an equilibrium
NaCN + H2O = NaOH +HCN
and that both compounds on the RHS were removed, driving the reaction forward, the NaOH by reaction with CO2 to form carbonate and the HCN by evaporation, the latter dispersing at low concentrations in the air.
Many years ago, in the 1970s, I wrote a couple of ICI-sponsored booklets for sixth form studies, one of which on antibacterials included an account of a timber processing firm using a large chlorophenol bath for preventing timber rotting. When the bath seemed to be losing its effectiveness they just tipped the contents down the drain. Result; a sewage farm in the Lea Valley which processed much of NE London's sewage just stopped working! There was a mad panic with fleets of tankers taking away the sewage until the treatment plant could be 'seeded' with new bacterial cultures.
The same booklet had a discussion of antibacterial resistance, too often now presented as a recent problem
Originally Posted by: DEW