Is Flex Printing Allowed In The City?

Hi, I have a doubt regarding one of our tenant. We have a tenant in our building who is having Flex printing business. It is in the prime location and while printing it smells horrible and it's harmful as well. We have told that tenant to take those flex printing machines out but he is not ready to do that. Could you please advise. Is flex printing allowed in cities when the gases are harmful for humans.