Cancer Prevalence in Karachi City by Use of Smokeless Tobacco Products

Abstract

The objective of this study is to measure the level of heavy metals such as As, Cd, Cr, Cu, Ni, Pb, Se, Co, Fe and Mn in smokeless tobacco products (STPs), to know about the ingredients used in the manufacture of STPs, to estimate the potential risk by calculating the daily intake (DImetals) and target hazard quotients (THQ). The individual incremental cancer risk (ILTR) of various types of smokeless tobacco products (STPs) and population incremental lifetime cancer risk (ILTR) of selected age groups for consumption of inorganic Arsenic (iAs) were also calculated to excess the cancer risk associated with the smokeless tobacco products (STPs). Samples of STPs and their major ingredients were randomly collected from different markets of Karachi city (Pakistan) and classified into different categories. Samples were digested by using the nitric acid (HNO3) and analyzed by atomic absorption spectroscopy. The daily consumption of STPs was calculated by a questioner, which helped to estimate daily intake of metals (DImetals) and target hazard quotient (THQ) of metals. The high concentration of As, Cr, Se, Fe and Mn were found, while Cu, Ni, Pb and Co were found in low concentration in different STPs. The consumption of STPs obtained as 5.11 – 42.38, 7.67 – 98.55 and 6.39 – 108.46 g/day for the three age groups, below 20, between 21- 40 and above 40 years respectively. The average metal concentration and multivariate analysis indicate that the source of As, Cr, Se, Fe and Mn may be associated with processing of STPs or addition of additive raw ingredients. The high ingestion beyond the safe limit of Cu, Ni, Pb and Co is noted in regards to their consumption pattern. The total THQ (TTHQ) of studied categories of STPs exceeded the safe limit of >1 which indicates the health risk and the ILTR values for individual types of STPs and population ILTR of different age groups specifies the cancer risk associated with their excessive use.