I had promised that I would share the recipe of non-polluting oil. Here it is:
Take one part palm oil, 200 ml coconut oil, 200 ml sesame oil and 200 ml castor oil and mix them in a slow fire. Add 100 gms ajwain, 50 gms cloves, a big bunch of neem leaves, half bunch tulsi leaves, 2 fistfuls of bael leaves and one bunch durva leaves. Boil the ingredients together. When it reaches its boiling point, stop the gas stove and cool it. Keep the resultant oil in a closed vessel. While lighting oil lamps, this oil is to be used and place a camphor tablet before lighting the lamp. The lamp should burn like a small bead. There is no repellent for microorganisms like this one.
These oil lamps can be lighted till the end of South Indian Kartigai Deepa Utsavam ends or even up to Makara Shankaranti.