Paula Lozano

Single-walled carbon nanotube behavior in representative mature leachate.

Escalating production and subsequent incorporation of engineered nanomaterials in consumer products increases the likelihood of nanomaterials being discarded in landfills. Although direct measurement of particle disposal has not yet occurred, life cycle assessments suggest that over 50% of nanomaterials produced will eventually reside in landfills. Laboratory-scale experiments were conducted to evaluate how organics (humic acid: 20-800 mg/L), ionic strength (100-400 mM NaCl), and pH (6-8) typical of mature leachates influence carbon nanotube surface charge, relative stability, and mobility through representative solid waste environments. Results from the batch experiments suggest that the presence of high molecular weight organics, such as humic acid, acts to stabilize carbon nanotubes present in leachate, even at high ionic strengths (>100 mM NaCl). These results also suggest that in mature landfill leachate, as long as humic acid is present, ionic strength (when represented as NaCl) will be a dominant factor influencing nanomaterial stability. Column experiment results indicate the carbon nanotubes may be mobile through solid waste, suggesting particle placement within landfills needs to be examined more closely.

A longitudinal study of electronic cigarette use and onset of conventional cigarette smoking and marijuana use among Mexican adolescents

PURPOSE This study evaluated whether e-cigarette trial among Mexican adolescents increased the likelihood of trial and use of conventional cigarettes or marijuana use at follow-up. METHOD A school-based longitudinal survey was conducted in 60 public middle schools from the three largest cities in Mexico. Students (12-13years old) were surveyed in 2015 and followed up 20 months later (n=6574). Generalized estimating equations models were used to evaluate the association between e-cigarette trial at baseline and conventional cigarettes smoking and marijuana use at follow-up. RESULT Adolescents who had tried e-cigarettes (but not cigarettes) at baseline were more likely to have tried conventional cigarettes at followup compared to adolescents who had tried neither e-cigarettes nor cigarettes (43% vs. 24%, respectively; RR 1.41, 95% CI 1.18-1.70). We also found that adolescents who had tried both conventional cigarettes and e-cigarettes at baseline were more likely to have tried marijuana at follow-up compared to adolescents who had tried neither tobacco product (20% vs. 4%, respectively; RR 2.67, 95% CI 1.78-4.02). Trial of only e-cigarettes was not independently associated with marijuana use at followup. CONCLUSIONS Adolescents who had tried e-cigarettes were more likely to have tried conventional cigarettes and marijuana 20 months later. Although e-cigarettes have been banned in Mexico, it is likely that additional policies and public health campaigns are needed to reduce adolescent use of e-cigarettes and its consequences.

Does neighborhood social cohesion modify the relationship between neighborhood social norms and smoking behaviors in Mexico

The aim of this study was to examine the separate and combined relationships of neighborhood social norms and neighborhood social cohesion with smoking behavior in a cohort of adult Mexican smokers. Neighborhood anti-smoking norms were measured as the proportion of residents in each neighborhood who believed that society disapproves of smoking. Perceived social cohesion was measured using a 5-item cohesion scale and aggregated to the neighborhood level. Higher neighborhood anti-smoking norms were associated with less successful quitting. Neighborhood social cohesion modified the relationship between neighborhood social norms and two smoking behaviors: smoking intensity and quit attempts. Residents of neighborhoods with weaker anti-smoking norms and higher social cohesion had lower smoking intensity and more quit attempts than residents living in other areas. Social cohesion may help buffer smoking behavior in areas with weak social norms.

The impact of neighbourhood violence and social cohesion on smoking behaviours among a cohort of smokers in Mexico

Background Recent increases in violent crime may impact a variety of health outcomes in Mexico. We examined relationships between neighbourhood-level violence and smoking behaviours in a cohort of Mexican smokers from 2011 to 2012, and whether neighbourhood-level social cohesion modified these relationships. Methods Data were analysed from adult smokers and recent ex-smokers who participated in waves 5 and 6 of the International Tobacco Control Mexico survey. Self-reported neighbourhood violence and social cohesion were asked of wave 6 survey participants (n=2129 current and former smokers, n=150 neighbourhoods). Neighbourhood-level averages for violence and social cohesion (ranges 4–14 and 10–25, respectively) were assigned to individuals. We used generalised estimating equations to determine associations between neighbourhood indicators and individual-level smoking intensity, quit behaviours and relapse. Results Higher neighbourhood violence was associated with higher smoking intensity (risk ratio (RR)=1.17, 95% CI 1.02 to 1.33), and fewer quit attempts (RR=0.72, 95% CI 0.61 to 0.85). Neighbourhood violence was not associated with successful quitting or relapse. Higher neighbourhood social cohesion was associated with more quit attempts and more successful quitting. Neighbourhood social cohesion modified the association between neighbourhood violence and smoking intensity: in neighbourhoods with higher social cohesion, as violence increased, smoking intensity decreased and in neighbourhoods with lower social cohesion, as violence increased, so did smoking intensity. Conclusions In the context of recent increased violence in Mexico, smokers living in neighbourhoods with more violence may smoke more cigarettes per day and make fewer quit attempts than their counterparts in less violent neighbourhoods. Neighbourhood social cohesion may buffer the impact of violence on smoking intensity.

Disentangling the roles of point-of-sale ban, tobacco retailer density and proximity on cessation and relapse among a cohort of smokers: findings from ITC Canada Survey

Objective To examine how point-of-sale (POS) display bans, tobacco retailer density and tobacco retailer proximity were associated with smoking cessation and relapse in a cohort of smokers in Canada, where provincial POS bans were implemented differentially over time from 2004 to 2010. Methods Data from the 2005 to 2011 administrations of the International Tobacco Control (ITC) Canada Survey, a nationally representative cohort of adult smokers, were linked via residential geocoding with tobacco retailer data to derive for each smoker a measure of retailer density and proximity. An indicator variable identified whether the smoker’s province banned POS displays at the time of the interview. Outcomes included cessation for at least 1 month at follow-up among smokers from the previous wave and relapse at follow-up among smokers who had quit at the previous wave. Logistic generalised estimating equation models were used to determine the relationship between living in a province with a POS display ban, tobacco retailer density and tobacco retailer proximity with cessation (n=4388) and relapse (n=866). Results Provincial POS display bans were not associated with cessation. In adjusted models, POS display bans were associated with lower odds of relapse which strengthened after adjusting for retailer density and proximity, although results were not statistically significant (OR 0.66, 95% CI 0.41 to 1.07, p=0.089). Neither tobacco retailer density nor proximity was associated with cessation or relapse. Conclusions Banning POS retail displays shows promise as an additional tool to prevent relapse, although these results need to be confirmed in larger longitudinal studies.

Patterns of awareness and use of electronic cigarettes in Mexico, a middle-income country that bans them: Results from a 2016 national survey

Among high-income countries, awareness and use of e-cigarettes is lower in countries with more restrictive e-cigarette regulations. Little is known about e-cigarettes in middle-income countries, many of which like Mexico, ban e-cigarette sales and marketing. The current study determined the national-level prevalence and correlates of e-cigarette awareness and consumption in Mexico. Data were analyzed from a 2016 nationally representative survey. Prevalence of e-cigarette awareness, trial and current use was estimated separately for adolescents (n = 12,436), adult nonsmokers (n = 36,966), and adult smokers (n = 7347). For each group, crude and adjusted logistic models regressed e-cigarette outcomes on sociodemographic and smoking-related variables, adjusting for the sampling design and weights. Prevalence varied across subgroups for e-cigarette awareness (adolescents = 45.3%; adult nonsmokers = 33.9%; adult smokers = 54.3%), e-cigarette trial (adolescents = 6.5%; adult nonsmokers = 2.6%; adult smokers = 18.2%) and current use of electronic cigarettes (adolescents = 1.1%; adult nonsmokers = 0.3%; adult smokers = 4.5%). Among adolescents and adults, current smoking and higher smoking frequency were significantly associated with e-cigarette awareness, trial and use. Among adolescents and nonsmokers, awareness, trial and use of e-cigarette were significantly lower among females than males. Among adult smokers, however, females were more likely to use e-cigarettes than males (AOR = 1.80; 95% CI = 1.08-3.02). Higher education and greater wealth increased the likelihood of trial of e-cigarettes among adult nonsmokers and smokers. Despite the ban on the distribution and sales of e-cigarettes, a substantial number of Mexicans, have access to e-cigarettes. Decision makers and advocates should consider e-cigarette regulations as recommended by the WHO, at the same time Mexico must invest in the infrastructure needed to enforce these regulations.

Smoking-Related Stigma: A Public Health Tool Or A Damaging Force ?

Background Tobacco control policies and other denormalization strategies may reduce tobacco use by stigmatizing smoking. This raises an important question: Does perceived smoking-related stigma contribute to a smokers decision to quit? The aim of this study was to evaluate if perceived smoking-related stigma was associated with smoking cessation outcomes among smokers in Mexico and Uruguay. Methods We analyzed prospective data from a panel of adult smokers who participated in the 2008-2012 administrations of the International Tobacco Control Policy Evaluation Surveys in Mexico and Uruguay. We defined two analytic samples of participants: the quit behavior sample (n=3896 Mexico; n=1525 Uruguay) and the relapse sample (n=596 Mexico). Generalized estimating equations were used to evaluate if different aspects of perceived stigma (i.e., discomfort, marginalization, and negative stereotype) at baseline were associated with smoking cessation outcomes at follow-up. Results We found that perceived smoking-related stigma was associated with a higher likelihood of making a quit attempt in Uruguay, but with a lower likelihood of successful quitting in Mexico. Conclusions This study suggests that perceived smoking-related stigma may be associated with more quit attempts, but less successful quitting among smokers. It is possible that once stigma is internalized by smokers, it may function as a damaging force. Future studies should evaluate the influence of internalized stigma on smoking behavior. Implications While perceived smoking-related stigma may prompt smokers to quit smoking, smoking stigma may also serve as a damaging force for some individuals, making quitting more difficult. This study found that perceived smoking-related stigma was associated with a higher likelihood of making a quit attempt in Uruguay, but with a lower likelihood of successful quitting in Mexico.

The role of social norms and socioeconomic status in smoking-related stigma among smokers in Mexico and Uruguay

Abstract Policies that promote the social unacceptability of smoking may also result in smoking-related stigma. The aim of this study is to evaluate how norms against smoking and socioeconomic status (SES) are associated with stigma among smokers. We used data from a panel of adult smokers who participated in the 2008–2012 administrations of the International Tobacco Control Policy Evaluation Survey in Mexico (n = 6670 observations) and Uruguay (n = 3296 observations). Generalized estimating equations were used to account for correlations in the outcomes over time within individuals. We evaluated if injunctive smoking norms (i.e. significant other norms and societal norms), descriptive smoking norms (i.e. number of smoking friends), and two markers of SES (i.e. education and income) were associated with different aspects of smoking-related stigma (i.e. feeling uncomfortable, negative stereotype of smokers, and perceived marginalization). We found that stronger anti-smoking injunctive norms were associated with higher levels of all indicators of perceived stigma in Mexico and Uruguay. Having fewer smoking friends was associated with feeling uncomfortable and perceived marginalization in Mexico. Higher income and education were associated with a stronger negative stereotype of smokers in Mexico. Lower income and education were associated with a stronger negative stereotype of smokers in Uruguay. Study results suggest that factors that drive the social unacceptability of tobacco may stigmatize smokers, although further research is needed to determine whether policy-promoted stigmatization produces undesirable outcomes (e.g. lower cessation rates).

Technophilia: A new risk factor for electronic cigarette use among early adolescents?

PURPOSE Develop and validate a scale that measures Technophilia (positive orientation toward new technology) and use it to address orientation toward new technologies to explain e-cigarette trial and adoption, especially in relatively low risk adolescents. METHODS Survey data were obtained from students of the three largest cities in Mexico (n = 8123). We developed eight questions involving access, use and pleasure from different electronic media to measure technophilia. Exploratory factor analysis (EFA) was conducted. Linear GEE models were used when regressing technophilia on covariates. When regressing e-cigarette and conventional cigarette trial and use, logistic GEE models were used. Finally, we used multinomial logistic regression to evaluate the associations between technophilia and e-cigarettes as the first tobacco product. RESULTS Technophilia were correlated with theoretically-related variables. Unadjusted and adjusted models regressing e-cigarette trial and use indicated that students in the highest quartile for technophilia were more likely to have tried e-cigarettes compared with the lowest quartile (AORQ4 vs Q1 = 1.36, 95% CI 1.14-1.62). Technophilia was not independently associated with current e-cigarette use in adjusted models. Students with higher technophilia were more likely to have first tried e-cigarettes in both crude and adjusted models (AORQ4vQ1 = 1.66, 95% CI 1.20-2.31; AORQ3vQ1 = 1.43, 95% CI 1.02-2.01). Technophilia did not have a statistically significant, independent association with first use of other tobacco products. CONCLUSION This study suggests that technophilia is associated with trial of e-cigarettes among youth. The measure we developed appears useful for understanding why some youth are open to trying novel, technologically oriented ways to consume nicotine.