Toxic metals in top selling cigarettes sold in China: Pulmonary bioaccessibility using simulated lung fluids and fuzzy health risk assessment

Abstract Determination of the pulmonary bioaccessible fraction and its induced health risk with respect to the toxic metals present in tobacco smoke is a significant issue, in terms of scientific and proactive management of clean tobacco production and smoker health. China, the world's largest producer and consumer of tobacco, has about 350 million smokers. The four typical toxic metals in the 20 top selling cigarette brands in China were investigated. The mean levels of As, Cd, Ni, and Pb in tobacco were 0.3891 μg/g, 3.8431 μg/g, 2.4356 μg/g, and 2.7718 μg/g, respectively. Pulmonary bioaccessibility was analyzed by extraction using simulated lung fluid (SLF), where the average rates of As, Cd, Ni, and Pb transferring from tobacco to SLF by mainstream smoke (RSLF) were 7.85%, 2.85%, 0.86%, and 3.45%, respectively. Considering the inhalation pathway of mainstream smoke, an improved health risk assessment (HRA) was conducted using local exposure parameters and fuzzification of sensitive variables. With consideration of the exposure differences of smokers, Cd and As were identified as the priority control metals, and B05, B11, B12, and B19 among the 20 brands (named B01–B20) were found to be the priority control brands. Furthermore, it is worth noting that the membership degrees of a small portion of brands which approached 50% could warn decision-makers of potentially misleading uncertainties. The daily consumption limit (DCL) for each studied brand was calculated, under the risk standard value of Level II (1.00E-05), generally ranging from 1–4 cigarette(s) per day. Spatially, DCLs in Southern, Southwestern, and Eastern China were relatively lower than those in other regions. At present, it is of significance to establish a national life-cycle supervisory system for Cd and As. Findings about the health risks posed by toxic metals through the tobacco–smoke–lung exposure pathway can provide scientific risk management reference for smokers, related managers, and producers.