Otimização de metodologias analíticas para determinação de nicotina e pesticidas organoclorados em tabaco de cigarro contrabandeado para o Brasil

Abstract

Since the concentration of nicotine and organochlorine pesticides are important parameter that reflects the quality of the tobacco used in the production of cigarettes, simple methods are necessary for this determination, which produce reduced amounts of waste, which becomes environmentally and industrially interesting. In view of the above, the objective of this work was to optimize two analytical methodologies for extracting nicotine and organochlorine pesticides in tobacco from cigarettes smuggled into Brazil were optimized since this study is of paramount relevance due to the increased consumption of smuggled cigarettes. In this work, the nicotine concentration of smuggled cigarette tobacco was determined by the QuEChERS method, requiring some modifications, such as decreasing the volume of the extractor solvent, changes in pH, and removal of the sample hydration step and the quantification was performed by gas chromatography using a flame ionization detector. The Doehlert matrix design was used to optimize the method. The extraction recoveries ranged from 97.5% to 99.6%, with relative standard deviation (RSD) ≤ 2.5% and limits of detection and quantification of 0.6 mg L-1 and 2.5 mg L-1 , respectively. The method was sensitive and accurate for the detection and quantification of nicotine being the the nicotine concentration was lower than in legal cigarettes. To quantify organochlorine pesticides using ultrasound application and low-temperature extraction. The combined approach was validated for 20 organochlorine pesticides, achieving recoveries ranging from 73 % to 116 % and a relative standard deviation of less than 20 %. The method minimized the matrix effect in 65 % of the organochlorine pesticides. The limits of detection and quantification varied from 2 to 60 ng g-1 and 120 to 190 ng g-1 , respectively. The method was applied to the analysis of 18 brands of smuggled cigarettes. The organochlorine pesticides found in the samples were cis chlordane (89 %), p,p dichlorodiphenyldichloroethylene (DDD), methoxychlor (78 %), endosulfan sulfate (67 %), heptachlor epoxide, and endosulfan II (61 %). The concentrations of the organochlorine pesticides in this study were higher than those in a similar survey on cigarettes marketed in China. The ultrasound application and low-temperature extraction may be an efficient alternative to analyzing tobacco samples since it uses only one extraction solvent, requires low-cost equipment, does not require an additional clean-up step, reduce environmental impact through minimal waste generation, and can detect low analyte concentrations. The methods were successfully applied to real samples of smuggled cigarettes, demonstrating an alternative for routine analysis and proving the need for more studies on this subject.