Comprehensive chemical characterization of Rapé tobacco products: Nicotine, un-ionized nicotine, tobacco-specific N'-nitrosamines, polycyclic aromatic hydrocarbons, and flavor constituents

Abstract

Rapé, a diverse group of smokeless tobacco products indigenous to South America, is generally used as a nasal snuff and contains substantial amount of plant material with or without tobacco. Previously uncharacterized, rapé contains addictive and harmful chemicals that may have public health implications for users. Here we report % moisture, pH, and the levels of total nicotine, un-ionized nicotine, flavor-related compounds, tobacco-specific N-nitrosamines (TSNAs) and polycyclic aromatic hydrocarbons (PAHs) for manufactured and hand-made rapé. Most rapé products were mildly acidic (pH 5.17-6.23) with total nicotine ranging from 6.32 to 47.6 milligram per gram of sample (mg/g). Calculated un-ionized nicotine ranged from 0.03 to 18.5 mg/g with the highest values associated with hand-made rapés (pH 9.75-10.2), which contain alkaline ashes. In tobacco-containing rapés, minor alkaloid levels and Fourier transform infrared spectra were used to confirm the presence of Nicotiana rustica, a high nicotine tobacco species. There was a wide concentration range of TSNAs and PAHs among the rapés analyzed. Several TSNAs and PAHs identified in the products are known or probable carcinogens according to the International Agency for Research on Cancer. Milligram quantities of some non-tobacco constituents, such as camphor, coumarin, and eugenol, warrant additional evaluation.

Keywords: Flavors; Nasal snuff; Nicotine; Rapé; Smokeless tobacco; Tobacco-specific nitrosamines.

Figure 1. Photograph of manufactured rapé product packaging

Manufactered Products: 1) Rapé Caratinga Imburana, 2) Rapé Caratinga Mentolado, 3) Rapé Araçá Cravo e Canela, 4) Rapé Guarany Especial (Canela), 5) Rapé Moeda Girassol, 6) Rapé Moeda Especial, 7) Rapé Cacitral, 8) Rapé Guarany Cravo, 9) Rapé Guarany Cristal, 10) Rapé Real (flavored), and 11) Rapé Real (unflavored). Products 7) and 9) did not contain tobacco. Products 12) Rapé Guarany Especial is not shown. Custom-made Products (not shown): 13) Rapé Kaxinawa and 14) Rapé Nu-nu did not have manufactured packaging.

Figure 2

Photographs of various rapés showing product texture and product color, which is influenced by the presence of tobacco and non-tobacco plant materials.

Figure 3

Tobacco Content (%) is based on a dose-dependent correlation between total nicotine (dry wt.) and tobacco content for rapé samples. Rapé Real (unflavored) was determined to be pure N. rustica (set as 100% tobacco, 50.9 mg/g) based on GC/MS and FT/IR analyses. Non-tobacco containing products with no detectable tobacco (i.e., 0 mg nicotine), including Rapé Cacitral and Rapé Guarany Cristal, and were set as 0% tobacco content in this regression.

Figure 4

Fourier transform infrared (FT/IR) spectra in the range from 425 – 3700 cm⁻¹. Comparison of: [A] Rape Real with Nicotiana tabacum and N. rustica; the IR spectra for N. glauca is not shown [B] Rapé Guarany Cristal (non-tobacco product) overlaid with pure tonka bean (seed and pods combined), [C] Rapé Guarany Cravo overlaid with ground clove buds. The hit quality index (HQI) for the Euclidian distance (1st derivative) is shown. The HQI scale is from 1 to 1000 for least similar to most similar to the reference spectra.