Does the concentration of cadmium and lead in tobacco smoke and the type of exposure influence blood pressure values?

In the realm of preventive medicine, reinforcement of a zero-tolerance stance on cigarette smoking is imperative. The use of heat-not-burn (HnB) technology by individuals who are unable to quit smoking has prompted strong discussions in both the public health and clinical domains. This raises the question of whether exposure to cigarettes or HnB products has a different effect on blood pressure (BP) values and whether this effect depends on the concentration of heavy metals. A total of 33 participants were divided into four exposure groups: passive HnB exposure (n=7), active HnB users (n=4), passive cigarette smokers (n=11), and active cigarette smokers (n=9). Blood concentrations of cadmium (Cd) and lead (Pb) were determined by atomic absorption spectroscopy (AAS) using a Graphite Furnace Atomic Absorption Spectrometer, Agilent 240Z AA (Agilent Technologies, Santa Clara, CA, USA). Samples were prepared by wet digestion with nitric acid solution. After centrifugation, the supernatant was transferred into vials for AAS analysis. Concentrations of Cd and Pb were measured before and after exposure, and changes were analyzed using generalized linear models (GLM) adjusted for sex, age, and body mass index (BMI). All participants were smokers who had stopped smoking five days prior to the experiment. None of the participants had any chronic diseases. After a five-day abstinence (washout period), they were exposed to active and passive consumption of HnB or traditional cigarettes. BP was measured before and after exposure to tobacco smoke. Average Cd levels were similar across all groups (p = 0.55): passive HnB 1.59 µg/L, active HnB 1.29 µg/L, passive cigarette smokers 1.65 µg/L, and active cigarette smokers 1.64 µg/L. Pb levels varied significantly by exposure type (p = 0.006), as follows: 35.95 µg/L with passive HnB exposure, 26.98 µg/L with active HnB exposure, 52.45 µg/L and 36.50 µg/L in passive and active cigarette smokers, respectively. Upon monitoring, an elevation in Cd levels was significantly associated with a rise in systolic pressure (p = 0.026) and a decrease in diastolic pressure (p = 0.006), indicating an increase in pulse pressure and potential arterial stiffness. Pb concentration showed no direct effect on hemodynamic parameters. These findings suggest that Cd and Pb levels vary based on type of exposure. There was a significant difference between traditional cigarettes and HNB products, with the latter exhibiting lower concentrations, as well as between active and passive exposure. Changes in BP tend to be more closely linked to Cd, as higher levels correlate with increased systolic and decreased diastolic pressures, indicating its role in arterial stiffness and early vascular dysfunction.