Ciprofloxacin antibiotic removal from aqueous solutions by ZnO nanoparticles coated on ACA: modeling and optimization.

Antibiotics are one of the most widely used drug groups. The presence of antibiotics in urban water sources and sewage creates many environmental and medical risks for humans and other living organisms. In this study, the potential of zinc oxide (ZnO) coated on almond shell activated carbon (ACA-ZnO) in removing ciprofloxacin (CIP) from aqueous solutions was investigated. Almond shell was used to make activated carbon. Zinc oxide nanoparticles were prepared by the sol-gel method, and finally, ZnO nanoparticles were bonded to activated carbon. The effect of independent parameters pH, contact time, adsorbent dose, and initial CIP concentration on CIP removal efficiency using ACA-ZnO was investigated by response surface methodology. Optimal removal was obtained at pH = 5.4, CIP initial concentration = 7.4 mg/L, adsorbent dose = 0.82 g/L, and reaction time = 67.3 min. This study followed a quadratic model (R2 = 0.958). The best model of adsorption isotherm fits with the Freundlich model (R2 = 0.9972) and the maximum capacity was 251.42 mg/g adsorption kinetics, and pseudo-second-order kinetic model (R2 = 0.959). The results of this study showed that ACA-ZnO as an adsorbent is very efficient, without environmental side effect and cost-benefit.

Waterpipe smoking among health sciences university students in Iran: perceptions, practices and patterns of use.

BACKGROUND: In recent years waterpipe smoking has become a popular practice amongst young adults in eastern Mediterranean countries, including Iran. The aim of this study was to assess waterpipe smoking perceptions and practices among first-year health sciences university students in Iran and to identify factors associated with the initiation and maintenance of waterpipe use in this population. RESULTS: Out of 371 first-year health sciences students surveyed, 358 eight students completed a self-administered questionnaire in the classrooms describing their use and perceptions towards waterpipe smoking. Two hundred and ninety six responders met study inclusion criteria. Waterpipe smoking was common among first-year health sciences university students, with 51% of students indicating they were current waterpipe smokers. Women were smoking waterpipes almost as frequently as men (48% versus 52%, respectively). The majority of waterpipe smokers (75.5%) indicated that the fun and social aspect of waterpipe use was the main motivating factor for them to continue smoking. Of waterpipe smokers, 55.3% were occasional smokers, using waterpipes once a month or less, while 44.7% were frequent smokers, using waterpipes more than once a month. A large number of frequent waterpipe smokers perceived that waterpipe smoking was a healthier way to use tobacco (40.6%) while only 20.6% thought it was addictive. Compared to occasional smokers, significantly more frequent smokers reported waterpipe smoking was relaxing (62.5% vs. 26.2%, p = 0.002), energizing (48.5% vs. 11.4%, p = 0.001), a part of their culture (58.8% vs. 34.1%, p = 0.04), and the healthiest way to use tobacco (40.6% vs. 11.1%, p = 0.005). CONCLUSIONS: Social and recreational use of waterpipes is widespread among first-year health sciences university students in Iran. Women and men were almost equally likely to be current waterpipe users. Public health initiatives to combat the increasing use of waterpipes among university students in Iran must consider the equal gender distribution and its perception by many waterpipe smokers as being a healthier and non-addictive way to use tobacco.