Most jurisdictions prohibit the use of asbestos as a gasket material in potable water systems even though there is still a lot of cementious asbestos pipe in service.
You best bet is check with the local jurisdiction that oversees the potable water supply.
I am working in water project at which BA-U Tesnit gasket is approved,this material is asbestos-free. after checking the delivered material I observed that some of the gaskets are Tesnit kemit super, which is asbestos gasket, I am planning to reject them, but I need to know alittle about the effect of using asbestos with potable water ??
I would send the wrong gasket material back without any explanation other than it is not the material specified.
Also being in the USA I wouldn't even carry an Asbestos to jobsite that involved potable water. There are just too many other food grade/potable water materials available.
In most states of the USA it is my understanding materials in contact with potable water are required to be listed per NSF/ANSI STANDARD 61 Drinking Water System Components - Health Effects. While I do not know how strongly this is being enforced in this particular aspect, this includes gasketing materials for water systems. An example of a gasket manufacturer who has gone through such formulation, testing, listing etc. processes is Specification Rubber Products, with resulting listings available at