Introduction:
Smokeless products being relatively economical are easily available and consumed by most of the common people throughout India. Pan masala is a mixture of areca nut, catechu, slaked lime, many artificial flavoring substances usually without tobacco. But tobacco is mixed and consumed along with it. Other than harmful contents already present, manufactures also add magnesium carbonate and calcium carbonate to alter pH and increase addictive potential.

Objectives:
To estimate magnesium carbonate, calcium carbonate and pH of pan masala and smokeless tobacco products commercially available in Mangalore, India.

Methods:
Two samples each of products such as pan masala, khaini, ghutka and zarda commercially available in Mangalore were selected for the study. Two grams of each sample was weighed accurately and ground well. Samples were filtered and collected. pH was measured using a Systronic digital pH meter. Standard methods were followed to quantify calcium carbonate and magnesium carbonate using the EDTA (Ethylenediaminetetraaceticacid) titration method. Each sample was done in duplicate. The amount of calcium carbonate, magnesium carbonate present was calculated.

Results:
Magnesium carbonate was highest in khaini with a mean value of 69.711mg/g and the least content in pan masala with a mean value of 20.91mg/g. Calcium carbonate was highest in zarda with a mean value of 8.333mg/g and least in khaini with a mean value of 6.781mg/g. pH was highest in khaini with a mean value 9.89 and least in zarda with a mean value of 7.23.

Conclusion(s):
Alkaline pH of smokeless tobacco products leads to rapid and easy absorption of free or unionized nicotine in the oral mucosa thus increasing its addictive potential. The current study shows that there is high content of calcium carbonate and alkaline additives such as magnesium carbonate which contribute to pH. These additives make these products further detrimental to health.