Similar to other man made materials such as fiberglass, carbon nanotubes, commercial cellulose, and of course asbestos; what is good for industry is often not good for people's health and disposal and handling are often not big concerns for the people manufacturing and selling these materials. This may be a serious problem in the future when these materials end up in the environment, where there interactions with natural systems in unpredictable.
Maybe these should be studied and understood before we go head long into production, maybe before all products in an entire market are replaced or modified to depend and accelerate nano material tech. Perhaps I'm just being alarmist, GMO foods have similar unknown complications and we already have been eating them in the USA for years without any problems at all.