I think the below points should make a huge difference within a short span of time.
- Educate employees with posters (that show the swollen mouth/ mouth cancer/ damaged lips etc, because of pan, gutka) that are direct, so that everytime they think of pan/ gutka/ smoking they will be aware of the future (near future) diseases they are likely to get etc
- Usually illiterate employees get into these habits due to boredom, so try some initiative to encourage some activities.
- STRICTLY BAN ALL SUCH ITEMS INSIDE THE COMPANY PREMISES & put a notice at the entrance gate (near the security guards cabin) mentioning that - "PAN, GUTKHA, BEEDI, CIGARETTE ARE NOT ALLOWED BEYOND THIS POINT"
- Also put a board (colour banner - 2feet x 2feet ) showing all the chota packets of the above items with a big red cross on them, since they are illiterate this should be easy to understand.
The idea of installing cctv cameras is a costly solution for a problem of this type, secondly installing cctv is not possible in toilets.
I think this will not hurt their sentiments, and will help in keeping the company premises clean.