With what can we replace mercury-containing biocides, which are becoming increasingly risky ?
A wide range of biocides which do not contain any heavy metals are now on the market. These include phenol derivatives such as p-chloro-m-cresol and sodium pentachlorophenolate, of which the first is use on its own in
emulsion paintor blended in equal parts with the second. Obviously there will be some risk of thickening. One can also use compounds such as hexaminium salts , benzyl formal, N-methylolchloraccetamide and chloroacetamide.
These cause little irritation and can be used on their own or blended with each other, Depending on whether it is more important to achieve a bactericidal or a fungicidal effect.
Other alternative product are the quaternary ammonium salts, although in this case one must check whether they are sufficient compatible with emulsifiers,