Reduction of aldehydes and hydrogen cyanide yields in mainstream cigarette smoke using an amine functionalised ion exchange resin

Abstract

BackgroundCigarette smoking is a well recognized cause of diseases such as lung cancer, chronic obstructive pulmonary disease and cardiovascular disease. Of the more than 5000 identified species in cigarette smoke, at least 150 have toxicological activity. For example, formaldehyde and acetaldehyde have been assigned as Group 1 and Group 2B carcinogens by IARC, and hydrogen cyanide has been identified as a respiratory and cardiovascular toxicant. Active carbon has been shown to be an effective material for the physical adsorption of many of the smoke volatile species. However, physical adsorption of acetaldehyde, formaldehyde and also hydrogen cyanide from smoke is less effective using carbon. Alternative methods for the removal of these species from cigarette smoke are therefore of interest. A macroporous, polystyrene based ion-exchange resin (Diaion®CR20) with surface amine group functionality has been investigated for its ability to react with aldehydes and HCN in an aerosol stream, and thus selectively reduce the yields of these compounds (in particular formaldehyde) in mainstream cigarette smoke.ResultsResin surface chemistry was characterized using vapour sorption, XPS, TOF-SIMS and 15N NMR. Diaion®CR20 was found to have structural characteristics indicating weak physisorption properties, but sufficient surface functionalities to selectively remove aldehydes and HCN from cigarette smoke. Using 60 mg of Diaion®CR20 in a cigarette cavity filter gave reductions in smoke formaldehyde greater than 50% (estimated to be equivalent to >80% of the formaldehyde present in the smoke vapour phase) independent of a range of flow rates. Substantial removal of HCN (>80%) and acetaldehyde (>60%) was also observed. The performance of Diaion®CR20 was found to be consistent over a test period of 6 months. The overall adsorption for the majority of smoke compounds measured appeared to follow a pseudo-first order approximation to second order kinetics.ConclusionsThis study has shown that Diaion®CR20 is a highly selective and efficient adsorbent for formaldehyde, acetaldehyde and HCN in cigarette smoke. The reductions for these compounds were greater than those achieved using an active carbon. The results also demonstrate that chemisorption can be an effective mechanism for the removal of certain vapour phase toxicants from cigarette smoke.

Changes in levels of biomarkers of exposure and biological effect in a controlled study of smokers switched from conventional cigarettes to reduced-toxicant-prototype cigarettes

“…The tobacco rod was 46 mm long and contained a blend of 50% washed, extracted and enzyme-treated tobacco , 15% tobacco substitute sheet (McAdam et al, 2011) and 35% other tobaccos. The filter was 37 mm long and comprised three cellulose acetate segments: the front segment, nearest the tobacco rod, contained 50 mg high-activity carbon (Branton et al, 2011a), the middle segment contained 20 mg aminefunctionalised resin (Branton et al, 2011b) and the mouth-end segment was plain cellulose acetate. Filter ventilation was 35%, achieved with a combination of on-machine laser perforation and a 10 mm wide zone of high-porosity paper (Dittrich et al, 2014).…”

Reference change values to assess changes in concentrations of biomarkers of exposure in individuals participating in a cigarette-switching study

“…Two groups of subjects continued to smoke the 1 mg and 6 mg commercial cigarettes for the remaining 4 weeks of the study (commercial control groups CC1 and CC6, respectively), whereas the others were switched to an RTP cigarette with the same ISO tar yield as their usual brand (one 6 mg ISO tar yield RTP, TSS6, or one of two 1 mg ISO tar yield RTPs: TSS1, which contained tobacco-substitute sheet in the blend and high activity carbon and amine-functionalised resin in the filter, or BT1, which contained water and enzyme-treated Virginia tobacco in the tobacco blend and the same filter as TSS1). These products are described in greater detail elsewhere [15,[19][20][21][22]. Urine samples were collected and cigarette consumption recorded in two further periods of clinical confinement (Supplemental Data, Figure 1, which accompanies the article at http://www.degruyter.com/view/j/ cclm.2014.52.issue-3/issue-files/cclm.2014.52.issue-3.xml).…”

Assessment of ovarian cancer conditions from exhaled breath

“…The exogenous source of the aldehydes indicates that aldehydes could be absorbed exogenously, versus from cigarettes, industrial emission or car exhaust entering the body and causing cell damage. 38 To learn more about the origin of the aldehydes, we need to understand the VOC kinetics in the body. The fat/blood partition coefficient (k f:b ) could indicate several important parameters.…”