Sulfamethoxazole is a common antibiotic that is frequently detected in wastewater and surface water. This study investigated the biodegradation and metabolic pathway of sulfamethoxazole by Pseudomonas psychrophila HA-4, a cold-adapted bacterium. Strain HA-4, which uses sulfamethoxazole as its sole source of carbon and energy, was isolated at a low temperature (10 °C) and identified as P. psychrophila by physico-biochemical characterization and 16S rRNA gene sequence analysis. Strain HA-4 removed sulfamethoxazole at temperatures ranging from 5.0 °C to 30 °C, with the maximal removal rate at 10 °C. The maximal removal rate of sulfamethoxazole by strain HA-4 was 34.30 % after 192 h at 10 °C. The highest percentage of unsaturated fatty acid was determined to be 23.03 % at 10 °C, which adheres to the characteristic for cold-adapted psychrophiles and psychrotrophs. At low concentrations of sulfamethoxazole, the growth kinetics correlated well with the Haldane model. The single-substrate parameter values of sulfamethoxazole on cell growth were determined to be μ max = 0.01 h(-1), K s = 20.91 mg/l and K i = 170.60 mg/l. Additionally, the major intermediates from sulfamethoxazole biodegradation by strain HA-4, including aniline, 3-amino-5-methylisoxazole, 4-aminothiophenol and sulfanilamide, were identified by GC-MS and high-resolution mass spectrometry (HR-MS) analysis. The results demonstrate that strain HA-4 has the potential to degrade sulfamethoxazole at low temperatures.

IntroductionThe tobacco product landscape has changed substantially. Little is known about the recent pattern of polytobacco use (at least two tobacco products) among US adults and its relationship to nicotine dependence.MethodsUsing the 2012–2013 and 2013–2014 National Adult Tobacco Survey (NATS) data (N = 135 425 adults), we analyzed the prevalence and correlates of polytobacco use among each of the six categories of current tobacco user (cigarettes, cigars, pipes, hookah, e-cigarettes, and smokeless tobacco). Based on five nicotine dependence symptom measures from the NATS, difference in the prevalence of dependence symptoms between polytobacco and sole-product users for each category of tobacco user was assessed using multivariable regression analyses.ResultsDuring 2012–2014, 25.1% of adults were current users of any tobacco product. Among them, 32.5% were poly users with the largest poly use category being dual use of cigarettes and e-cigarettes (30.2%). Poly use prevalence was the lowest among current cigarette smokers (38.7%), followed by current users of smokeless tobacco (52.4%), hookah (59.2%), cigars (69.3%), e-cigarettes (80.9%), and pipes (86.2%). Among each category of current tobacco user, the prevalence of dependence symptom was consistently greater in polytobacco users than sole users for every symptom measure. After controlling for frequency of use and demographic covariates, the difference in nicotine dependence between poly users and sole users was statistically significant and consistent across all symptom measures for each category of tobacco user.ConclusionsBetween 52% and 86% of noncigarette tobacco users and nearly 40% of cigarette smokers engaged in polytobacco use. Poly users showed greater nicotine dependence than sole-product tobacco users.ImplicationsThis study examines recent patterns of polytobacco use separately for US adult current cigarette smokers, cigar smokers, pipe smokers, hookah users, e-cigarette users, and smokeless tobacco users. By including more tobacco products, particularly e-cigarettes and hookah, this study provides more comprehensive insight into polytobacco use. This study is also unique in comparing nicotine dependence between polytobacco and sole-product users among each category of tobacco users. Our results indicate that polytobacco use is very common and is associated with greater likelihood of reporting nicotine dependence symptoms. Tobacco cessation policies and programs should be tailored to address polytobacco use.

Introduction: Tobacco use prevalence has been commonly estimated on a product by product basis and the extent of polytobacco use among current users of each tobacco product is not well understood. This study aimed to examine the prevalence, trends, and correlates of polytobacco use among current users of cigarettes, cigars, chewing tobacco, and snuff in US adults aged ≥18. Methods: We used pooled data from the 1998, 2000, 2005, and 2010 Cancer Control Supplements of the National Health Interview Survey (N = 123 399 adults). Multivariate logistic regression models were estimated to determine significant factors associated with polytobacco use. Results: In 2010, the prevalence of polytobacco use was 8.6% among current cigarette smokers, 50.3% among current cigar users, 54.8% among current chewing tobacco users, and 42.5% among current snuff users. After controlling for other covariates, gender and race/ethnicity did not show consistent associations with poly-use across these four groups of current tobacco users; however, a positive association of young adulthood, less than high school education, and binge drinking with poly-use was consistently found among all these groups. Conclusions: Polytobacco use is extremely popular among current users of non-cigarette tobacco products. Polytobacco use patterns differ across sociodemographic subpopulations, and the gender and racial/ethnic profiles in poly-users vary across different groups of current tobacco users. Tobacco control strategies need to consider the interrelationships in the use of different tobacco products and the diverse profiles of poly-users in order to develop tailored tobacco prevention and intervention policies to further reduce the burden of tobacco use. 818Nicotine & Tobacco Research, 2016, Vol. 18, No. 5 use has been linked to oral and pharyngeal cancers, bladder and pancreatic cancer, oral leukoplakia, periodontal disease, and hypercholesterolemia.9-12 Because different tobacco products have potentially different levels of addiction and toxicity, 3 polytobacco use may be associated with increased risks of nicotine dependence, 13 adverse health effects, 14 and healthcare utilization compared with exclusive use of a single tobacco product. To evaluate the potential effects of polytobacco use on population health and health-related economic burden, it is crucial to understand the pattern of poly-use and the demographic profile of poly-users.The prevalence of tobacco use has been commonly estimated on a product by product basis in population-level surveillance studies, [15][16][17][18] and the extent of polytobacco use among current users of each tobacco product, especially non-cigarette product, is not well understood. In the literature of polytobacco use among US adults, except few recent studies which examined lifetime polytobacco use, , and relatively few studies estimated the prevalence of current polytobacco use among current users of all tobacco products combined (9.9%−12.1% of those aged ≥26 and 21.4%−24.6% of those aged 18−25), 39 ...

ObjectiveTo examine the relationship between spending on electronic cigarettes (e-cigarettes) and disease symptoms compared with the relationship between 30-day e-cigarette use and disease symptoms among adult cigarette smokers in the U.S.MethodsWe analyzed data from the Tobacco and Attitudes Beliefs Survey which included 533 respondents aged 24+ who were current cigarette smokers and e-cigarette ever users. Fifteen self-reported disease symptoms were included as outcome variables. Separate multivariable logistic regression models were estimated for each disease symptom with total spending on e-cigarettes in the past 30 days and with reported 30-day e-cigarette use. All models controlled for cigarettes smoked per day (CPD) and sociodemographic characteristics.ResultsWe found that those who spent more on e-cigarettes were more likely to report chest pain (AOR = 1.25, 95% CI 1.02–1.52), to notice blood when brushing their teeth (AOR = 1.23, 95% CI 1.02–1.49), to have sores or ulcers in their mouth (AOR = 1.36, 95% CI 1.08–1.72), and to have more than one cold (AOR = 1.36, 95% CI 1.05–1.78) than those with no spending on e-cigarettes in the past 30 days in an adjusted analysis. After controlling for CPD and other covariates, there were no significant relationships between 30-day e-cigarette use and symptoms. Even after controlling for CPD, e-cigarette expenditures or use was associated with greater odds of wheezing and shortness of breath.ConclusionsE-cigarette expenditures might be a more useful measure of intensity of e-cigarette use. The additional health effect of e-cigarette use or expenditures among smokers independent of the effect of CPD suggests that e-cigarette use adds adverse health effects even among cigarette smokers.