In addition to ongoing breach of implied warranty of habitability, discrimination, harassment, and retaliation, my landlord has done major repairs in my unit - changing of flooring, bathroom/hallway cabinets, and ceiling scraping - without providing me with asbestos surveys on newly used/replaced materials or even obtain the necessary permit from the SQAQMD before starting the repairs. The former's field inspector declined to cite the landlord for the evident/admitted violations in his presence - not to mention other agencies' inspectors reluctance/negligence to document physically/visually witnessed violations in their reports - and the landlord has not replied to my thus-far mailed letters, to its property management office, entailing all my concerns/questions/clarifications/requests.
Construction / Development Lawyer
Call the health department, the building department and/or the rent control board in Los Angeles to see if they can help you. As for the landlord responding to every one of your demands, he does not necessarily have to.
If you are concerned about possible health issues, you should find a new place to live.
Contact an attorney right away - this is a landlord/tenant issue and you may be justified in withholding rent - however, do not do this on your own. You need to be advised by an attorney!
This is my opinion and should not be construed as legal advise for your specific case as there are many more facts which you have not provided.