Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
13,686
result(s) for
"Carcinogens - analysis"
Sort by:
A Randomized Clinical Trial Examining the Effects of Instructions for Electronic Cigarette Use on Smoking-Related Behaviors and Biomarkers of Exposure
Abstract
Introduction
Electronic cigarettes (e-cigarettes) have the potential to significantly reduce exposure to harmful constituents associated with cigarette smoking when smokers completely substitute cigarettes with e-cigarettes. This study examined patterns of e-cigarette and cigarette use, and extent of toxicant exposure, if smokers were instructed and incentivized to completely switch to e-cigarettes compared to instructions to use the product ad libitum.
Aims and Methods
US adult daily smokers (n = 264; 49.2% female; Mage = 47.0), uninterested in quitting smoking immediately, were recruited from Minneapolis, MN, Columbus, OH, and Buffalo, NY. Participants were randomized to 8 weeks of instructions for (1) ad libitum use of e-cigarettes (AD-E), (2) complete substitution of cigarettes with e-cigarettes (CS-E), (3) complete substitution of cigarettes with nicotine gum or lozenge (CS-NRT), or (4) continue smoking of usual brand cigarettes (UB). Participants were incentivized for protocol compliance, including complete switching in the CS-E and CS-NRT groups. Outcome variables were cigarette smoking rate and tobacco-related biomarkers of exposure.
Results
Smokers in the CS-E and CS-NRT groups showed lower rates of smoking and lower exposure to carbon monoxide, tobacco carcinogens, and other toxicants than smokers in the AD-E group. In general, no significant differences were observed between CS-E versus CS-NRT or between AD-E versus UB for most biomarkers. Significantly higher 7-day point prevalence smoke-free rates were observed for CS-E versus CS-NRT.
Conclusions
Smokers instructed and incentivized to completely switch to e-cigarettes resulted in lower smoking rates and greater reductions in exposures to harmful chemicals than smokers instructed to use the product ad libitum.
Implications
Smokers instructed to completely substitute e-cigarettes for cigarettes displayed significantly lower levels of smoking and biomarkers of exposure to carcinogens and toxicants, compared to smokers instructed to use e-cigarettes ad libitum and similar levels as smokers instructed to completely substitute with nicotine replacement therapies. Furthermore, a higher rate of complete switching was achieved with e-cigarettes versus nicotine replacement therapies. Approaches to maximize complete substitution with e-cigarettes are an important area for future research.
Journal Article
Five-Day Changes in Biomarkers of Exposure Among Adult Smokers After Completely Switching From Combustible Cigarettes to a Nicotine-Salt Pod System
Abstract
Introduction
This study examined changes in biomarkers of exposure (BoE) after 5 days of nicotine-salt pod system (NSPS) use, compared with continuation of usual-cigarette smoking and cigarette abstinence, among adult combustible cigarette smokers.
Aims and Methods
A randomized, open-label, parallel-cohort, confinement study of healthy adult smokers, naive to NSPS use, was conducted. Participants (N = 90) were randomized to six cohorts (n = 15 each): exclusive ad libitum use of NSPS (four flavors: Virginia Tobacco, Mint, Mango, Creme), continuation of usual-brand cigarette smoking, or cigarette abstinence. Total nicotine equivalents and BoE (NNN, NNAL, 3-HPMA, MHBMA, S-PMA, HMPMA, CEMA, 1-OHP, and COHb) were measured.
Results
Eight non-nicotine BoEs, measured in urine, were reduced by an aggregate of 85.0% in the pooled NSPS cohort; increased by 14.4% in the cigarette cohort (p < .001 for pooled NSPS vs. cigarette); and reduced by 85.3% in the abstinence cohort (p > .05; 99.6% relative reduction between pooled NSPS vs. abstinence). Similar changes in individual BoEs were also observed (p < .001 for each BoE between pooled NSPS vs. cigarettes; and abstinence vs. pooled NSPS; p > .05 for each BoE between pooled NSPS vs. abstinence). Blood COHb decreased by 71.8% in the pooled NSPS cohort and 69.1% in the abstinence cohort (p > .05) and increased by 13.3% in the cigarette cohort (p < .001). Mean total urine nicotine equivalents increased in the pooled NSPS and cigarette cohorts by 9% and 26%, respectively, and did not significantly differ (p > .05).
Conclusion
Complete switching from cigarettes to NSPS produced significant reductions in key non-nicotine BoEs associated with cigarette smoking.
Implications
The results of this study concorded with evidence that complete switching from combustible cigarettes to tobacco and nontobacco-flavored vapor products may reduce exposure to key carcinogens and other toxicants known to be associated with tobacco-related diseases. Future research is needed to assess the long-term health effects of NSPS use. These results should not be interpreted to mean that the use of NSPS is without any risk, particularly for nonusers of tobacco products.
Journal Article
Electrocautery smoke exposure and efficacy of smoke evacuation systems in minimally invasive and open surgery: a prospective randomized study
Worldwide, health care professionals working in operating rooms (ORs) are exposed to electrocautery smoke on a daily basis. Aims of this study were to determine composition and concentrations of electrocautery smoke in the OR using mass spectrometry. Prospective observational study at a tertiary care academic center, involving 122 surgical procedures of which 84 were 1:1 computer randomized to smoke evacuation system (SES) versus no SES use. Irritating, toxic, carcinogenic and mutagenic VOCs were observed in OR air, with some exceeding permissible exposure limits (OSHA/NIOSH). Mean total concentration of harmful compounds was 272.69 ppb (± 189 ppb) with a maximum total concentration of harmful substances of 8991 ppb (at surgeon level, no SES). Maximum total VOC concentrations were 1.6 ± 1.2 ppm (minimally-invasive surgery) and 2.1 ± 1.5 ppm (open surgery), and total maximum VOC concentrations were 1.8 ± 1.3 ppm at the OR table ‘at surgeon level’ and 1.4 ± 1.0 ppm ‘in OR room air’ away from the operating table. Neither difference was statistically significant. In open surgery, SES significantly reduced maximum concentrations of specific VOCs at surgeon level, including aromatics and aldehydes. Our data indicate relevant exposure of health care professionals to volatile organic compounds in the OR. Surgical technique and distance to cautery devices did not significantly reduce exposure. SES reduced exposure to specific harmful VOC’s during open surgery.
Trial Registration Number: NCT03924206 (clinicaltrials.gov).
Journal Article
Thirdhand Smoke in the Homes of Medically Fragile Children
Thirdhand smoke (THS) residue results from secondhand smoke, and is emerging as a distinct public health hazard, particularly for medically fragile pediatric patients living with smokers. THS is difficult to remove and readily reacts with other pollutants to form carcinogens and ultrafine particles. This study investigated THS found in homes of high-risk infants admitted to a neonatal intensive care unit and their association with characteristics (eg, number of household smokers) hypothesized to influence THS.
Baseline data from 141 hospitalized infants' homes were analyzed, along with follow-up data (n = 22) to explore household smoking characteristics and THS changes in response to indoor smoking ban policies.
Households with an indoor ban, in which not more than 10 cigarettes/d were smoked, had the lowest levels of THS contamination compared to homes with no ban (P < .001) and compared to homes with an indoor ban in which greater numbers of cigarettes were smoked (P < .001). Importantly, homes with an indoor ban in which at least 11 cigarettes/d were smoked were not different from homes without a ban. The follow-up sample of 22 homes provided initial evidence indicating that, unless a ban was implemented, THS levels in homes continued to increase over time.
Preliminary longitudinal data suggest that THS may continue to accumulate in homes over time and household smoking bans may be protective. However, for homes with high occupant smoking levels, banning indoor smoking may not be fully adequate to protect children from THS. Unless smoking is reduced and bans are implemented, medically fragile children will be exposed to the dangers of THS.
Journal Article
Assessing Constituent Levels in Smokeless Tobacco Products
Providing accurate information about the constituents in nicotine-containing products may help tobacco users make informed decisions about product choices. An experimental study examined a novel approach for presenting accurate constituent information about brands and types of smokeless tobacco (SLT) that could be understood by the general public.
Participants were recruited through Amazon's Mechanical Turk and presented information online about 2 constituent dimensions of SLT products-nicotine and/or toxicity (for simplicity, \"toxicity\" in this study refers to carcinogenic constituents) Participants completed measures of knowledge and tobacco health risks at 2 time points: before and after exposure to constituent information.
Participants were found to increase their knowledge that toxicity contributes to disease risk and nicotine contributes to addiction, that SLT products vary in their levels of nicotine and toxicity, and that both SLT and cigarette products have higher toxicity than medicinal nicotine replacement therapies (e.g., nicotine lozenges). Study results showed no differences when presenting toxicity information alone versus presenting it in conjunction with nicotine information, and found no misperceptions or confusions about the relative harmfulness of cigarettes, SLT, or nicotine replacement therapy.
Providing tobacco constituent information to smokers and nonsmokers will improve their knowledge about the relative toxicity across products and variations within a class of tobacco products without compromising the health risks associated with tobacco use.
Journal Article
Levels of nicotine and tobacco-specific nitrosamines in oral nicotine pouches
BackgroundNicotine pouches without tobacco are new products that deliver nicotine into the body via the oral mucosa. There is a lack of independent research on the chemical composition and product characteristics of these products, contributing to uncertainties regarding product regulation. This study sought to address knowledge gaps by assessing levels of nicotine and screening for tobacco-specific nitrosamines (TSNAs) in a sample of these products.MethodsNicotine pouches (n=44) and nicotine-free pouches (n=2) from 20 different manufacturers were analysed regarding their contents of nicotine and TSNAs by gas chromatography with flame ionisation and liquid chromatography–tandem mass spectrometry, respectively. Product labelling and pH values of aqueous extracts were determined.ResultsNicotine contents of products ranged from 1.79 to 47.5 mg/pouch; median product weight, pH, and proportion of free-base nicotine were 0.643 g, 8.8, and 86%, respectively. A clear labelling of the nicotine content was missing on 29 products and nicotine strength descriptions were ambiguous. TSNAs were detected in 26 products, with a maximum of 13 ng N-nitrosonornicotine/pouch.ConclusionAlthough nicotine pouches may potentially be a reduced risk alternative for cigarette smokers or users of some other oral tobacco products, nicotine contents of some pouches were alarmingly high. Presence of carcinogenic TSNAs in the nicotine pouches is of serious concern. Better manufacturing processes and quality control standards should be implemented. Labels of nicotine strength on most products are misleading. A strict regulation regarding nicotine contents and its labelling would be advisable.
Journal Article
Levels of selected carcinogens and toxicants in vapour from electronic cigarettes
Significance Electronic cigarettes, also known as e-cigarettes, are devices designed to imitate regular cigarettes and deliver nicotine via inhalation without combusting tobacco. They are purported to deliver nicotine without other toxicants and to be a safer alternative to regular cigarettes. However, little toxicity testing has been performed to evaluate the chemical nature of vapour generated from e–cigarettes. The aim of this study was to screen e-cigarette vapours for content of four groups of potentially toxic and carcinogenic compounds: carbonyls, volatile organic compounds, nitrosamines and heavy metals. Materials and methods Vapours were generated from 12 brands of e-cigarettes and the reference product, the medicinal nicotine inhaler, in controlled conditions using a modified smoking machine. The selected toxic compounds were extracted from vapours into a solid or liquid phase and analysed with chromatographic and spectroscopy methods. Results We found that the e-cigarette vapours contained some toxic substances. The levels of the toxicants were 9–450 times lower than in cigarette smoke and were, in many cases, comparable with trace amounts found in the reference product. Conclusions Our findings are consistent with the idea that substituting tobacco cigarettes with e-cigarettes may substantially reduce exposure to selected tobacco-specific toxicants. E-cigarettes as a harm reduction strategy among smokers unwilling to quit, warrants further study. (To view this abstract in Polish and German, please see the supplementary files online.)
Journal Article
Heavy metals contamination in urban surface soils of Medak province, India, and its risk assessment and spatial distribution
The main purpose of the current study is to assess the contamination status, human health risk, and spatial distribution of heavy metals in the urban soils from the Medak province in India. For this purposes, a total of 40 urban surface soil samples were collected and analyzed seven heavy metals including chromium (Cr), copper (Cu), cadmium (Cd), arsenic (As), nickel (Ni), lead (Pb), and zinc (Zn). The results of the study showed that the concentration of Cr (81–751 mg/kg), Cu (2–180 mg/kg), Zn (25–108 mg/kg), Pb (5–77 mg/kg), Ni (1–50 mg/kg), As (0.4–14 mg/kg), and Cd (0.1–4.2 mg/kg), respectively, was found above their natural background values. The geo-accumulation index analysis indicated that except Zn, all other tested heavy metals had a range of moderately to heavily polluted/contaminated in the study region. Spatial distribution pattern analysis inferred that the soil heavy metal (Cu, Cr, Zn, and Ni) pollutions in western regions of Medak were relatively larger than that in central and eastern regions. The hazard index (HI) values for Cu, Cd, Zn, As, Pb, and Ni were below 1, implying that there is no non-carcinogenic risks exposure from these heavy metals in soil for children and adults in the study region. However, HI value for Cr ranged from 3.08E−01 to 2.86E+00 for children, implying that children were relatively vulnerable population than adults in the current study region. Comparatively speaking, 67.5% and 100% total carcinogenic risks for Cr values for adults and children were larger than the acceptable threshold value of 1.0E−04, indicating chromium poses the greatest carcinogenic risk in the study region.
Journal Article
Heavy metals pollution assessment and its associated human health risk evaluation of urban soils from Indian cities: a review
Urban soils of 32 Indian cities were collected from literature-based data for the period of 2001–2019 to measure the contamination levels of six heavy metals including arsenic (As), chromium (Cr), copper (Cu), zinc (Zn), nickel (Ni), and lead (Pb) and also evaluated the potential human health risk for adults and children. The results indicated that concentrations of six heavy metals in the urban soils were much higher than both geochemical background values (Grade-I) and also Canadian soil quality guideline values (Grade-II) in most of the cities in India. Higher concentration of Cr and Ni was in cities mainly located in southern (Karnataka), northern (Uttar Pradesh), and eastern (Odisha); As and Pb primarily in central (Telangana), while Zn and Cu largely in western (Maharashtra) and eastern (Jharkhand) states of India, respectively. The index of geo-accumulation (Igeo) values varied largely and showed moderately polluted to extremely polluted levels, possibly caused/influenced by anthropogenic activity in the urban regions in India. The non-carcinogenic health risk due to Cu, Zn, Ni, and Pb in most urban regions was lower than the threshold value (HI < 1), indicating no non-carcinogenic health risk for adults and children. As and Cr on children, non-carcinogenic risk was very higher than that of adults, and their risk values were also exceeded the threshold value, indicating that As and Cr in the urban soils posed considerable non-carcinogenic health risks on urban residents. The total carcinogenic/cancer risk due to Pb in most urban regions was lower than the recommended limit of 1.00E−04, while Cr and As have shown potential cancer risk for both adults and children. Therefore, As and Cr are the sole heavy metals that cause potential health risk in an urban region residents in India, which needs to be paid more attention and also controlling measures should be initiated.
Journal Article