Analysis of Tobacco-Specific Nitrosamines in the Common Smokeless Tobacco Afzal in Oman

Toxic effects of smokeless tobacco on female reproductive health: A review

•

Smokeless tobacco use can lead to impairments of ovarian function, morphology, oocyte quality and hormonal regulation.

•

Use of smokeless tobacco during pregnancy has adverse health effects on both the mother and fetus.

•

Exposure to smokeless tobacco in utero has long term health consequences on offspring.

The habitual consumption of tobacco in its various form is widespread and a serious public health issue globally. In particular, the use of smokeless tobacco has increased substantially due to its easy availability and misconception that it is relatively harmless compared to smoking. Tobacco use has been well established from numerous studies as a causative agent of devastating illnesses such as cancer, insulin resistance, hypertension, acute respiratory disease, osteoporosis, etc. Limited but growing evidence have also suggested its role in adversely affecting reproductive capabilities and outcomes in women of reproductive age and during pregnancy. This paper provides an updated review on available literature regarding the negative effects of smokeless tobacco use on female reproductive health, during pregnancy and its adverse consequences on the offspring. Existing data suggests the association between chronic smokeless tobacco use and impairment of ovarian morphology and function, oocyte quality, hormonal perturbations, fetal development and long-term health effects on the fetus. Improved understanding of these issues can contribute to better awareness of the dangers of smokeless tobacco products.

Global burden of disease due to smokeless tobacco consumption in adults: an updated analysis of data from 127 countries

BACKGROUND

Smokeless tobacco (ST) is consumed by more than 300 million people worldwide. The distribution, determinants and health risks of ST differ from that of smoking; hence, there is a need to highlight its distinct health impact. We present the latest estimates of the global burden of disease due to ST use.

METHODS

The ST-related disease burden was estimated for all countries reporting its use among adults. Using systematic searches, we first identified country-specific prevalence of ST use in men and women. We then revised our previously published disease risk estimates for oral, pharyngeal and oesophageal cancers and cardiovascular diseases by updating our systematic reviews and meta-analyses of observational studies. The updated country-specific prevalence of ST and disease risk estimates, including data up to 2019, allowed us to revise the population attributable fraction (PAF) for ST for each country. Finally, we estimated the disease burden attributable to ST for each country as a proportion of the DALYs lost and deaths reported in the 2017 Global Burden of Disease study.

RESULTS

ST use in adults was reported in 127 countries; the highest rates of consumption were in South and Southeast Asia. The risk estimates for cancers were also highest in this region. In 2017, at least 2.5 million DALYs and 90,791 lives were lost across the globe due to oral, pharyngeal and oesophageal cancers that can be attributed to ST. Based on risk estimates obtained from the INTERHEART study, over 6 million DALYs and 258,006 lives were lost from ischaemic heart disease that can be attributed to ST. Three-quarters of the ST-related disease burden was among men. Geographically, > 85% of the ST-related burden was in South and Southeast Asia, India accounting for 70%, Pakistan for 7% and Bangladesh for 5% DALYs lost.

CONCLUSIONS

ST is used across the globe and poses a major public health threat predominantly in South and Southeast Asia. While our disease risk estimates are based on a limited evidence of modest quality, the likely ST-related disease burden is substantial. In high-burden countries, ST use needs to be regulated through comprehensive implementation of the World Health Organization Framework Convention for Tobacco Control.

Comparison of tobacco-specific nitrosamine levels in smokeless tobacco products: High levels in products from Bangladesh

Bangladesh exhibits the second highest rate of smokeless tobacco (SLT) product usage in the world, and this has been associated with the high upper aerodigestive tract cancer incidence in this country. The goal of the present study was to examine the levels of the highly carcinogenic tobacco-specific nitrosamines (TSNAs) in Bangladeshi SLT products and compare these levels to that observed in SLT brands from southeast Asia and the USA. The levels of TSNAs and nicotine were determined by LC-MS/MS in twenty-eight SLT brands and several tobacco additives from Bangladesh, as well as several SLT brands from India, Pakistan and the USA. The levels of N-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N-nitrosoanatabine (NAT) and N-nitrosoanabasine (NAB) in Bangladeshi SLT brands ranged from 1.1-59, 0.15-34, 0.79-45, and 0.037-13 μg/g SLT powder, respectively. The mean levels of the highly carcinogenic TSNAs (NNN+NNK) were 7.4-, 2.4-, and 63-fold higher in Bangladeshi SLT products as compared to SLT brands from the USA, India and Pakistan, respectively; these trends were also observed for NAT and NAB. Similar mean levels of nicotine were observed in the Bangladeshi brands (31 mg/g powder) versus brands from the USA (25 mg/g powder) and India (20 mg/g powder); they were 3-fold higher than brands from Pakistan (10 mg/g powder). Gul SLT brands exhibited the highest pH and the highest levels of unprotonated nicotine. The high levels of TSNAs in Bangladeshi SLT brands may be an important factor contributing to the high rates of upper aerodigestive tract cancer in Bangladesh.

Regulation of toxic contents of smokeless tobacco products

Effective regulation of contents of tobacco products is one of the primary milestones to reduce negative health effects associated with the use of smokeless tobacco (SLT) products. As per the available sources, testing of some SLT products has been done on ad hoc basis, but there is a lack of comprehensive and periodic analysis of these products. In addition, the available results indicate huge variations among the levels of pH, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone, N-nitrosonornicotine, benzo[a]pyrene, heavy metals and nicotine within different products as well as within different brands of the same product. This review was aimed to throw light on the variations and gaps in testing of SLT products and emphasize the need for strong policy regulation for monitoring the chemical constituents of these products.