Nicotine, Cotinine, and Tobacco-Specific Nitrosamines Measured in Children's Silicone Wristbands in Relation to Secondhand Smoke and E-cigarette Vapor Exposure

INTRODUCTION

Simple silicone wristbands (WB) hold promise for exposure assessment in children. We previously reported strong correlations between nicotine in WB worn by children and urinary cotinine (UC). Here, we investigated differences in WB chemical concentrations among children exposed to secondhand smoke from conventional cigarettes (CC) or secondhand vapor from electronic cigarettes (EC), and children living with nonusers of either product (NS).

METHODS

Children (n = 53) wore three WB and a passive nicotine air sampler for 7 days and one WB for 2 days, and gave a urine sample on day 7. Caregivers reported daily exposures during the 7-day period. We determined nicotine, cotinine, and tobacco-specific nitrosamines (TSNAs) concentrations in WB, nicotine in air samplers, and UC through isotope-dilution liquid chromatography with triple-quadrupole mass spectrometry.

RESULTS

Nicotine and cotinine levels in WB in children differentiated between groups of children recruited into NS, EC exposed, and CC exposed groups in a similar manner to UC. WB levels were significantly higher in the CC group (WB nicotine median 233.8 ng/g silicone, UC median 3.6 ng/mL, n = 15) than the EC group (WB nicotine median: 28.9 ng/g, UC 0.5 ng/mL, n = 19), and both CC and EC group levels were higher than the NS group (WB nicotine median: 3.7 ng/g, UC 0.1 ng/mL, n = 19). TSNAs, including the known carcinogen NNK, were detected in 39% of WB.

CONCLUSIONS

Silicone WB show promise for sensitive detection of exposure to tobacco-related contaminants from traditional and electronic cigarettes and have potential for tobacco control efforts.

IMPLICATIONS

Silicone WB worn by children can absorb nicotine, cotinine, and tobacco-specific nitrosamines, and amounts of these compounds are closely related to the child's urinary cotinine. Levels of tobacco-specific compounds in the silicone WB can distinguish patterns of children's exposure to secondhand smoke and e-cigarette vapor. Silicone WB are simple to use and acceptable to children and, therefore, may be useful for tobacco control activities such as parental awareness and behavior change, and effects of smoke-free policy implementation.

Remediating Thirdhand Smoke Pollution in Multiunit Housing: Temporary Reductions and the Challenges of Persistent Reservoirs

INTRODUCTION

Toxic tobacco smoke residue, also known as thirdhand smoke (THS), can persist in indoor environments long after tobacco has been smoked. This study examined the effects of different cleaning methods on nicotine in dust and on surfaces.

AIMS AND METHODS

Participants had strict indoor home smoking bans and were randomly assigned to: dry/damp cleaning followed by wet cleaning 1 month later (N = 10), wet cleaning followed by dry/damp cleaning (N = 10) 1 month later, and dry/damp and wet cleaning applied the same day (N = 28). Nicotine on surfaces and in dust served as markers of THS and were measured before, immediately after, and 3 months after the cleaning, using liquid chromatography with triple quadrupole mass spectrometry (LC-MS/MS).

RESULTS

Over a 4-month period prior to cleaning, surface nicotine levels remained unchanged (GeoMean change: -11% to +8%; repeated measures r = .94; p < .001). Used separately, dry/damp and wet cleaning methods showed limited benefits. When applied in combination, however, we observed significantly reduced nicotine on surfaces and in dust. Compared with baseline, GeoMean surface nicotine was 43% lower immediately after (z = -3.73, p < .001) and 53% lower 3 months later (z = -3.96, p < .001). GeoMean dust nicotine loading declined by 60% immediately after (z = -3.55, p < .001) and then increased 3 months later to precleaning levels (z = -1.18, p = .237).

CONCLUSIONS

Cleaning interventions reduced but did not permanently remove nicotine in dust and on surfaces. Cleaning efforts for THS need to address persistent pollutant reservoirs and replenishment of reservoirs from new tobacco smoke intrusion. THS contamination in low-income homes may contribute to health disparities, particularly in children.

IMPLICATIONS

Administered sequentially or simultaneously, the tested cleaning protocols reduced nicotine on surfaces by ~50% immediately after and 3 months after the cleaning. Nicotine dust loading was reduced by ~60% immediately after cleaning, but it then rebounded to precleaning levels 3 months later. Cleaning protocols were unable to completely remove THS, and pollutants in dust were replenished from remaining pollutant reservoirs or new secondhand smoke intrusion. To achieve better outcomes, cleaning protocols should be systematically repeated to remove newly accumulated pollutants. New secondhand smoke intrusions need to be prevented, and remaining THS reservoirs should be identified, cleaned, or removed to prevent pollutants from these reservoirs to accumulate in dust and on surfaces.

Persistent tobacco smoke residue in multiunit housing: Legacy of permissive indoor smoking policies and challenges in the implementation of smoking bans

Secondhand smoke (SHS) is a common indoor pollutant in multiunit housing (MUH). It is also the precursor of thirdhand smoke (THS), the toxic mixture of tobacco smoke residue that accumulates in indoor environments where tobacco has been used. This study examined the levels, distribution, and factors associated with THS pollution in low-income MUH. Interviews were conducted 2016-2018 in a cross-sectional study of N = 220 MUH homes in San Diego, California. Two surface wipe samples were collected per home and analyzed for nicotine, a THS marker, using liquid chromatography-triple quadrupole mass spectrometry. Nicotine was detected in all homes of nonsmokers with indoor smoking bans (Geo Mean = 1.67 µg/m²; 95% CI = [1.23;2.30]) and smokers regardless of an indoor ban (Geo Mean = 4.80 µg/m²; 95% CI = [1.89;12.19]). Approximately 10% of nonsmokers' homes with smoking bans showed nicotine levels higher than the average level in homes of smokers without smoking bans from previous studies (≥30 µg/m²). Housing for seniors, smoking bans on balconies, indoor tobacco use, difficult to reach surfaces, and self-reported African-American race/ethnicity were independently associated with higher THS levels. Individual cases demonstrated that high levels of surface nicotine may persist in nonsmoker homes for years after tobacco use even in the presence of indoor smoking bans. To achieve MUH free of tobacco smoke pollutants, attention must be given to identifying and remediating highly polluted units and to implementing smoking policies that prevent new accumulation of THS. As THS is a form of toxic tobacco product waste, responsibility for preventing and mitigating harmful impacts should include manufacturers, suppliers, and retailers.

Nicotine in thirdhand smoke residue predicts relapse from smoking cessation: A pilot study

INTRODUCTION

Thirdhand smoke (THS) residue lingers for months in homes of former smokers and may play a role in relapse after smoking cessation. This study examined the association between THS pollution as measured by the level of nicotine in house dust and continued abstinence from smoking.

METHODS

Participants were 65 cigarette smokers who reported they were enrolled in any type of smoking cessation program, had set a specific date to quit, and had biochemical verification of continuous abstinence at 1-week (W1), 1-month (M1), 3-months (M3), or 6-months (M6) after their quit date. House dust samples collected at baseline before quitting were analyzed for nicotine concentration (μg/g) and nicotine loading (μg/m²) using liquid chromatography-tandem mass spectrometry (LC-MS/MS).

RESULTS

Controlling for age, gender, overall and indoor smoking rates, and years lived in their home, dust nicotine concentration and loading predicted abstinence at W1, M1, M3, and M6. A 10-fold increase in dust nicotine loading and concentration were associated with approximately 50% lower odds of remaining abstinent.

CONCLUSIONS

Findings suggest nicotine in house dust may play a role in facilitating relapse after smoking cessation. Additional research is warranted to investigate the causal role of THS residue in homes of former smokers on cravings and continued abstinence.

Nicotine levels in silicone wristband samplers worn by children exposed to secondhand smoke and electronic cigarette vapor are highly correlated with child's urinary cotinine

Exposure assessment in children, especially young children, presents difficulties not found with adults. Simple silicone wristbands are passive samplers that have potential applicability in exposure studies of children. We investigated the performance of silicone wristbands as personal nicotine samplers in two wristbands worn by a child (n = 31) for 7 days and for 2 days (worn day 5 to day 7). We compared levels of nicotine in wristbands with urinary cotinine, a metabolite of nicotine, measured in the child's urine obtained on day 7. Children were recruited who were exposed to contaminants in tobacco smoke and/or vapor from electronic nicotine delivery systems (ENDS; commonly known as electronic cigarettes or EC) as well as children who lived in nonsmoking homes. Caregivers were interviewed to obtain reported measures of the child's exposure. Analysis was by liquid chromatography with triple quadrupole mass spectrometry and isotope dilution (LC-MS/MS). The nicotine detected in the wristbands worn for 2 days was highly correlated with urinary cotinine concentration (df = 29, r² = 0.741, p < 0.001), as was nicotine in wristbands worn for 7 days (df = 28, r² = 0.804, p < 0.001). The 2- and 7-day wristband nicotine amounts were also significantly correlated (df = 28, r² = 0.852, p < 0.001). Silicone wristbands may be a useful tool for epidemiological and intervention studies of tobacco product exposure in children.

Cotton pillows: A novel field method for assessment of thirdhand smoke pollution

Thirdhand smoke (THS) is the residue left behind by secondhand smoke (SHS) that accumulates in indoor environments. THS chemicals can persist long after smoking has ceased and can re-emit semivolatile compounds back into the air. Measuring tobacco smoke pollution in real-world field setting can be technically complex, expensive, and intrusive. This study placed pillows in homes of former smokers and examined how much nicotine adsorbed to them over a three-week period. Organic cotton pillows were placed in the homes of 8 former smokers following the first week after verified smoking cessation until the fourth week. For comparison, pillows were also placed in 4 homes of nonsmokers. Nicotine concentrations were determined in the pillow case, fabric, and cotton filling, using isotope-dilution liquid chromatography tandem mass spectrometry. Cotton pillows placed in homes of former smokers absorbed on average 21.5 μg of nicotine. Nicotine concentration per gram of material significantly differed between pillow components (p < 0.001) and was highest for the pillow case (257 ng/g), followed by the pillow fabric (97 ng/g), and the pillow filling (17 ng/g). Nicotine levels in pillows placed in nonsmokers' homes did not differ from laboratory blanks (p > 0.40), or between pillow components (p > 0.40). In the absence of any smoking activity, cotton pillows absorbed significant amounts of nicotine emitted from THS reservoirs in the homes of former smokers. Given the much higher concentrations of SHS in the homes of active smokers, fabrics found throughout the home of a smoker are likely to store a substantial mass of tobacco smoke toxicants. Cotton pillows present a novel method that could be of interest to researchers requiring robust and unobtrusive methods to examine tobacco smoke pollution in real-world field settings.

A Casino goes smoke free: a longitudinal study of secondhand and thirdhand smoke pollution and exposure

Background

Secondhand smoke (SHS) in US casinos is common, but little is known about the residue of tobacco smoke pollutants left behind in dust and on surfaces, commonly referred to as thirdhand smoke (THS). We examined SHS and THS pollution and exposure before and during a casino smoking ban and after smoking resumed.

Methods

A casino was visited nine times over a 15-month period to collect dust, surface and air samples in eight locations. Finger wipe and urine samples were collected from non-smoking confederates before and after a 4-hour casino visit. Samples were analysed for markers of SHS and THS pollution and exposure.

Results

Exceptionally high levels of THS were found in dust and on surfaces. Although the smoking ban led to immediate improvements in air quality, surface nicotine levels were unchanged and remained very high for the first month of the smoking ban. Surface nicotine decreased by 90% after 1 month (P<0.01), but nicotine and tobacco-specific nitrosamines in dust decreased more slowly, declining by 90% only after 3 months (P<0.01). Exposure was significantly reduced after the ban, but the benefits of the ban were reversed after smoking resumed.

Conclusions

Long-term smoking in a casino creates deep THS reservoirs that persist for months after a smoking ban. A complete smoking ban immediately improves air quality and significantly reduces exposure to SHS and THS. However, THS reservoirs contribute to continued low-level exposure to toxicants. To accelerate the effect of smoking bans, remediation efforts should address specific THS reservoirs, which may require intensive cleaning as well as replacement of carpets, furniture and building materials.

Hotel smoking policies and their implementation: a survey of California hotel managers

BACKGROUND

Most states in the U.S. permit hotels to allow smoking in some guest rooms, and only five (Indiana, Michigan, North Dakota, Vermont, and Wisconsin) require that all hotel and motel rooms be 100% smoke-free (State and local 100% smokefree hotel and motel guest room laws enacted as of July 3, 2017). Little is known, however, about how hotels' smoking policies have been implemented. This study examined hotels' smoking policies and their implementation.

METHODS

A telephone survey of a random sample of 383 California hotel managers was conducted.

RESULTS

Overall, 60.6% of hotels reported that smoking was prohibited in all guest rooms, and 4.7% reported that smoking was prohibited everywhere on their property. While California law permitted smoking in up to 65% of guest rooms, only 6.9% of rooms were reported as smoking-permitted. Over 90% of hotels had smoking rooms scattered among nonsmoking rooms, and about half of the smoking hotels reported that guests requesting either smoking or nonsmoking rooms were sometimes assigned to the other room type. When guests smoked in nonsmoking rooms fees could be substantial, but were often uncollected.

CONCLUSIONS

Hotel smoking policies and their implementation fall short of protecting nonsmoking guests and workers from exposure to secondhand and thirdhand smoke. Complete indoor smoking bans for all hotels are needed to close existing loopholes. Nonsmokers who wish to protect themselves from exposure to tobacco smoke should avoid hotels that permit smoking and instead stay in completely smoke-free hotels.

When smokers quit: exposure to nicotine and carcinogens persists from thirdhand smoke pollution

BACKGROUND

Over a 6-month period, we examined tobacco smoke pollutants (also known as thirdhand smoke, THS) that remained in the homes of former smokers and the exposure to these pollutants.

METHODS

90 smokers completed study measures at baseline (BL). Measures were repeated among verified quitters 1 week (W1), 1 month (M1), 3 months (M3) and 6 months (M6) following cessation. Measures were analysed for THS pollutants on household surfaces, fingers and in dust (ie, nicotine, tobacco-specific nitrosamines) and for urinary markers of exposure (ie, cotinine, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL)).

RESULTS

We observed significant short-term reduction of nicotine on surfaces (BL: 22.2 μg/m², W1: 10.8 μg/m²) and on fingers of non-smoking residents (BL: 29.1 ng/wipe, W1: 9.1 ng/wipe) without further significant changes. Concentrations of nicotine and nicotine-derived nitrosamine ketone (NNK) in dust did not change and remained near BL levels after cessation. Dust nicotine and NNK loadings significantly increased immediately following cessation (nicotine BL: 5.0 μg/m², W1: 9.3 μg/m²; NNK BL: 11.6 ng/m², W1: 36.3 ng/m²) before returning to and remaining at near BL levels. Cotinine and NNAL showed significant initial declines (cotinine BL: 4.6 ng/mL, W1: 1.3 ng/mL; NNAL BL: 10.0 pg/mL, W1: 4.2 pg/mL) without further significant changes.

CONCLUSIONS

Homes of smokers remained polluted with THS for up to 6 months after cessation. Residents continued to be exposed to THS toxicants that accumulated in settled house dust and on surfaces before smoking cessation. Further research is needed to better understand the consequences of continued THS exposure after cessation and the efforts necessary to remove THS.

Thirdhand smoke and exposure in California hotels: non-smoking rooms fail to protect non-smoking hotel guests from tobacco smoke exposure

INTRODUCTION

This study examined tobacco smoke pollution (also known as thirdhand smoke, THS) in hotels with and without complete smoking bans and investigated whether non-smoking guests staying overnight in these hotels were exposed to tobacco smoke pollutants.

METHODS

A stratified random sample of hotels with (n=10) and without (n=30) complete smoking bans was examined. Surfaces and air were analysed for tobacco smoke pollutants (ie, nicotine and 3-ethynylpyridine, 3EP). Non-smoking confederates who stayed overnight in guestrooms provided urine and finger wipe samples to determine exposure to nicotine and the tobacco-specific carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone as measured by their metabolites cotinine and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), respectively.

FINDINGS

Compared with hotels with complete smoking bans, surface nicotine and air 3EP were elevated in non-smoking and smoking rooms of hotels that allowed smoking. Air nicotine levels in smoking rooms were significantly higher than those in non-smoking rooms of hotels with and without complete smoking bans. Hallway surfaces outside of smoking rooms also showed higher levels of nicotine than those outside of non-smoking rooms. Non-smoking confederates staying in hotels without complete smoking bans showed higher levels of finger nicotine and urine cotinine than those staying in hotels with complete smoking bans. Confederates showed significant elevations in urinary NNAL after staying in the 10 most polluted rooms.

CONCLUSIONS

Partial smoking bans in hotels do not protect non-smoking guests from exposure to tobacco smoke and tobacco-specific carcinogens. Non-smokers are advised to stay in hotels with complete smoking bans. Existing policies exempting hotels from complete smoking bans are ineffective.

Wipe sampling for nicotine as a marker of thirdhand tobacco smoke contamination on surfaces in homes, cars, and hotels

INTRODUCTION

Secondhand smoke contains a mixture of pollutants that can persist in air, dust, and on surfaces for months or longer. This persistent residue is known as thirdhand smoke (THS). Here, we detail a simple method of wipe sampling for nicotine as a marker of accumulated THS on surfaces.

METHODS

We analyzed findings from 5 real-world studies to investigate the performance of wipe sampling for nicotine on surfaces in homes, cars, and hotels in relation to smoking behavior and smoking restrictions.

RESULTS

The intraclass correlation coefficient for side-by-side samples was 0.91 (95% CI: 0.87-0.94). Wipe sampling for nicotine reliably distinguished between private homes, private cars, rental cars, and hotels with and without smoking bans and was significantly positively correlated with other measures of tobacco smoke contamination such as air and dust nicotine. The sensitivity and specificity of possible threshold values (0.1, 1, and 10 μg/m(2)) were evaluated for distinguishing between nonsmoking and smoking environments. Sensitivity was highest at a threshold of 0.1 μg/m(2), with 74%-100% of smoker environments showing nicotine levels above threshold. Specificity was highest at a threshold of 10 μg/m(2), with 81%-100% of nonsmoker environments showing nicotine levels below threshold. The optimal threshold will depend on the desired balance of sensitivity and specificity and on the types of smoking and nonsmoking environments.

CONCLUSIONS

Surface wipe sampling for nicotine is a reliable, valid, and relatively simple collection method to quantify THS contamination on surfaces across a wide range of field settings and to distinguish between nonsmoking and smoking environments.

Environmental tobacco smoke as a source of polycyclic aromatic hydrocarbons in settled household dust

Environmental tobacco smoke is a major contributor to indoor air pollution. Dust and surfaces may remain contaminated long after active smoking has ceased (called 'thirdhand' smoke). Polycyclic aromatic hydrocarbons (PAHs) are known carcinogenic components of tobacco smoke found in settled house dust (SHD). We investigated whether tobacco smoke is a source of PAHs in SHD. House dust was collected from 132 homes in urban areas of Southern California. Total PAHs were significantly higher in smoker homes than nonsmoker homes (by concentration: 990 ng/g vs 756 ng/g, p = 0.025; by loading: 1650 ng/m(2) vs 796 ng/m(2), p = 0.012). We also found significant linear correlations between nicotine and total PAH levels in SHD (concentration, R(2) = 0.105; loading, R(2) = 0.385). Dust collected per square meter (g/m(2)) was significantly greater in smoker homes and might dilute PAH concentration in SHD inconsistently. Therefore, dust PAH loading (ng PAH/m(2)) is a better indicator of PAH content in SHD. House dust PAH loadings in the bedroom and living room in the same home were significantly correlated (R(2) = 0.468, p < 0.001) suggesting PAHs are distributed by tobacco smoke throughout a home. In conclusion, tobacco smoke is a source of PAHs in SHD, and tobacco smoke generated PAHs are a component of thirdhand smoke.

Towards smoke-free rental cars: an evaluation of voluntary smoking restrictions in California

INTRODUCTION

Some car rental companies in California and other states in the USA have established non-smoking policies for their vehicles. This study examined the effectiveness of these policies in maintaining smoke-free rental cars.

METHODS

A stratified random sample of 250 cars (non-smoker, smoker and unknown designation) was examined in San Diego County, California, USA. Dust, surfaces and the air of each vehicle cabin were sampled and analysed for residual tobacco smoke pollutants (also known as thirdhand smoke (THS)), and each car was inspected for visual and olfactory signs of tobacco use. Customer service representatives were informally interviewed about smoking policies.

FINDINGS

A majority of putative non-smoker cars had nicotine in dust, on surfaces, in air and other signs of tobacco use. Independent of a car's smoking status, older and higher mileage cars had higher levels of THS pollution in dust and on surfaces (p<0.05), indicating that pollutants accumulated over time. Compared with smoker cars, non-smoker cars had lower levels of nicotine on surfaces (p<0.01) and in dust (p<0.05) and lower levels of nicotine (p<0.05) and 3-ethynylpyridine (p<0.05) in the air. Non-smoking signage in cars was associated with lower levels of THS pollutants in dust and air (p<0.05).

CONCLUSIONS

Existing policies and practices were successful in lowering THS pollution levels in non-smoker cars compared with smoker cars. However, policies failed in providing smoke-free rental cars; THS levels were not as low as those found in private cars of non-smokers with in-car smoking bans. Major obstacles include inconsistent communication with customers and the lack of routine monitoring and enforcement strategies. Strengthening policies and their implementation would allow car rental companies to reduce costs, better serve their customers and make a constructive contribution to tobacco control efforts.

When smokers move out and non-smokers move in: residential thirdhand smoke pollution and exposure

BACKGROUND

This study examined whether thirdhand smoke (THS) persists in smokers' homes after they move out and non-smokers move in, and whether new non-smoking residents are exposed to THS in these homes.

METHODS

The homes of 100 smokers and 50 non-smokers were visited before the residents moved out. Dust, surfaces, air and participants' fingers were measured for nicotine and children's urine samples were analysed for cotinine. The new residents who moved into these homes were recruited if they were non-smokers. Dust, surfaces, air and new residents' fingers were examined for nicotine in 25 former smoker and 16 former non-smoker homes. A urine sample was collected from the youngest resident.

RESULTS

Smoker homes' dust, surface and air nicotine levels decreased after the change of occupancy (p<0.001); however dust and surfaces showed higher contamination levels in former smoker homes than former non-smoker homes (p<0.05). Non-smoking participants' finger nicotine was higher in former smoker homes compared to former non-smoker homes (p<0.05). Finger nicotine levels among non-smokers living in former smoker homes were significantly correlated with dust and surface nicotine and urine cotinine.

CONCLUSIONS

These findings indicate that THS accumulates in smokers' homes and persists when smokers move out even after homes remain vacant for 2 months and are cleaned and prepared for new residents. When non-smokers move into homes formerly occupied by smokers, they encounter indoor environments with THS polluted surfaces and dust. Results suggest that non-smokers living in former smoker homes are exposed to THS in dust and on surfaces.

Adolescents validly report their exposure to secondhand smoke

OBJECTIVE

This study examined the validity of child-reported exposure to secondhand smoke (SHS) and investigated factors, such as child's age, which might affect accuracy of recall.

STUDY DESIGN AND SETTING

Participants were drawn from a nonprobability sample of 380 families who completed baseline assessment as part of a randomized trial of an SHS reduction intervention conducted in an urban setting in Southern California. Parents and children (aged 8-13 years) retrospectively reported child's exposure to SHS using timeline followback methodology; reports were compared with child's urine cotinine.

RESULTS

Validity coefficients for parents and children were comparable (r=0.58 vs. r=0.53), but parents recalled three times more exposure than children (2.2 vs. 0.8 cigarettes per day; P<0.001). Regression models predicting cotinine indicated that including child in addition to parent reports resulted in better prediction than either alone.

CONCLUSION

When there is a choice, parent reports are preferable over child reports because of decreased underreporting. However, child-reported SHS exposure had adequate validity (r>0.50) and might be appropriate in some situations. Researchers might consider collecting both parent and child reports because each made a unique contribution to the prediction of cotinine.

Counseling to reduce children's secondhand smoke exposure and help parents quit smoking: a controlled trial

INTRODUCTION

We tested a combined intervention to reduce children's secondhand smoke exposure (SHSe) and help parents quit smoking.

METHODS

After baseline, mothers who exposed their children younger than 4 years to 10 or more cigarettes/week were randomized to the intervention (n = 76) or usual care control condition (n = 74). Outcomes were assessed at 3, 6, 12, and 18 months. Intervention families were offered 10 in-person at home and 4 telephone counseling sessions over 6 months, and additional pre- and postquit telephone sessions. Counseling procedures included behavioral contracting, self-monitoring, and problem solving.

RESULTS

Parents' reports of their smoking and children's exposure showed moderate and significant correlations with children's urine cotinine levels and home air nicotine (r = .40-.78). Thirteen (17.1%) intervention group mothers and 4 (5.4%) controls reported that they quit smoking for 7 days prior to 1 or more study measurements, without biochemical contradiction (p = .024). Results of generalized estimating equations showed significantly greater decrease in reported SHSe and mothers' smoking in the counseled group compared with controls. Reported indoor smoking and children's urine cotinine decreased, yet group differences for changes were not significant.

DISCUSSION

Nicotine contamination of the home and resulting thirdhand exposure may have contributed to the failure to obtain a differential decrease in cotinine concentration. Partial exposure to counseling due to dropouts and lack of full participation from all family members and measurement reactivity in both conditions may have constrained intervention effects. Secondhand smoke exposure counseling may have been less powerful when combined with smoking cessation.

Parent quit attempts after counseling to reduce children's secondhand smoke exposure and promote cessation: main and moderating relationships

INTRODUCTION

This study explored predictors of smoking quit attempts in a sample of low-income smoking mothers who participated in a randomized trial of a 6-month, 14-session counseling intervention to decrease their children's secondhand smoke exposure (SHSe) and eliminate smoking.

METHODS

Measures were taken at baseline and at 3, 6, 12, and 18 months on 150 mothers who exposed their children (aged <4 years) to > or = 10 cigarettes/week in the home. Reported 7-day quits were verified by saliva cotinine or urine anabasine and anatabine levels.

RESULTS

There were few quits longer than 6 months. Mothers in the counseling group reported more 24-hr quits (p = .019) and more 7-day quits (p = .029) than controls. Multivariate modeling revealed that having quit for at least 24 hr in the year prior to baseline and the number of alternative cessation methods ever tried were predictive of the longest quit attempt during the 18-month study. Mothers in the counseling group who at baseline felt SHSe posed a health risk for their children or who at baseline had more permissive home smoking policies had longer quit attempts.

DISCUSSION

Results confirm that attempts to quit smoking predict additional quit attempts. This suggests that practice may be necessary for many people to quit smoking permanently. Findings of interaction analyses suggest that participant factors may alter the effects of treatment procedures. Failure to account for or employ such factors in the analysis or design of community trials could confound the results of intervention trials.

Fidelity issues in secondhand smoking interventions for children

This paper reviews methodological and theoretical fidelity of secondhand smoking (SHS) intervention studies (n = 29) that target protection of children in their home. In 2005, interventions were evaluated in terms of treatment fidelity according to guidelines provided by Borrelli et al. of the National Institutes of Health Behavior Change Consortium. The degree of fidelity was evaluated based on the percentage of criteria met; the inter-rater reliability based on percent agreement across independent raters was 0.78. Analysis indicated that studies with higher treatment fidelity were more likely to obtain statistically significant results (p = .003) with the average fidelity rating of 0.74 for statistically significant studies vs. 0.50 for statistically non-significant studies. Higher treatment fidelity was also significantly associated with being a more recent investigation (year 2000 or later), an efficacy as compared to effectiveness trial, more intensive as compared to less intensive intervention, a trial in the U.S. as compared to foreign nations, and having a theoretical basis. After taking all other variables into account, only treatment fidelity was significantly related to study outcome (p = .052). Ratings of treatment fidelity were ranked and compared to previous rankings based on 342 behavioral change interventions; the rank-ordered correlation between previous and current ratings was 0.84, although median fidelity ratings were 0.10 points lower in the previous than in the present study (0.52 vs. 0.62; intraclass correlation = 0.79). Improvements to the treatment fidelity evaluation guidelines were suggested, including the consideration of theoretical fidelity. Enhancing methodological and theoretical fidelity will speed identification of valid theoretical precepts that will, in turn, guide effective public health prevention programs.

Evaluation of urinary trans-3'-hydroxycotinine as a biomarker of children's environmental tobacco smoke exposure

The utility of urinary trans-3'-hydroxy cotinine (3HC) as a biomarker of environmental tobacco smoke (ETS) exposure was investigated in comparison with urinary cotinine (COT), the sum (3HC + COT), and ratio of the two nicotine metabolites (3HC/COT). Participants were 150 ETS exposed children (aged 1-44 months) and their parents. Child urine samples were collected during 3weekly baseline assessments and at interviews administered 3, 6, 12, and 18 months after baseline. Findings indicate that 3HC and COT can be measured reliably (rho = 0.96, 0.88) and show equivalent levels of repeated measures stability (rho = 0.71, 0.75). COT, 3HC, and 3HC + COT showed equally strong associations with air nicotine levels, reported ETS contamination, and reported ETS exposure (r=0.60-0.70). The intraclass correlations of 3HC/COT were lower than those for COT or 3HC. Older children had a higher 3HC/COT ratio than younger children (3.5 versus 2.2), and non-Hispanic White children had a higher ratio than African-American children (3.2 versus 1.9). These findings suggest that COT, 3HC, and 3HC + COT are approximately equivalent and equally strong biomarkers of ETS exposure in children. Moreover, 3HC/COT may provide a useful indicator to investigate age- and race-related differences in the metabolism of COT and 3HC.

Behavioral counseling for reducing children's ETS exposure: implementation in community clinics

The present randomized controlled trial tested the effectiveness of a behavioral counseling program for reducing children's exposure to environmental tobacco smoke (ETS). Counseling was delivered by clinic staff as part of well-child health care services in a community clinic setting. A total of 150 mothers with children aged 4 years or younger were recruited. Parent-reported and children's urinary cotinine measures of ETS exposure were obtained at baseline, 3 months, 6 months (post-test), and 12 months (follow-up). Saliva samples were obtained from mothers who reported quitting smoking, for objective verification by thiocyanate analysis. After baseline, mothers were randomly assigned to a measures-only control condition or an intervention consisting of seven behavioral counseling sessions over 6 months. Counseling included behavioral contracting, self-monitoring, problem solving, and positive reinforcement. Results indicated acceptable test-retest reliability and validity of measures. Parent-reported measures indicated that, in both groups, children's exposure to their mothers' tobacco smoke in the home and to all tobacco smoke declined steeply from baseline to 6 months post-test, and remained essentially level during follow-up. Mothers' smoking rates followed the same pattern. Children's urinary cotinine concentrations did not show significant change over time in either group. Findings on the fidelity of treatment implementation suggest that the structure and funding of the community clinic health care system and associated staff turnover and training issues resulted in participants receiving a less efficacious intervention than in our past efficacy trials. Implications for future effectiveness trials are discussed.

Measuring secondhand smoke exposure in babies: the reliability and validity of mother reports in a sample of low-income families

The reliability and validity of mother's reports of their infants' exposure to secondhand smoke (SHS) were examined in an ethnically diverse sample of low-income, low-education families (N = 141 mothers). At baseline and posttest, smoking mothers reported about their infants' SHS exposure at different locations and by different sources during the previous week. Findings show that mothers can give reliable accounts of the degree to which they contribute to their babies' SHS exposure. Mothers are able to differentiate between their own smoking behavior and the extent to which they expose their infants. Consistent with the overall exposure pattern, exposure caused by the mother and exposure occurring at home showed the strongest associations with biological and environmental measures. These findings suggest that smoking mothers can provide reliable and valid reports of the degree to which their infants are exposed to SHS.

Reported measures of environmental tobacco smoke exposure: trials and tribulations

OBJECTIVE

This report extends previous summaries of reported environmental tobacco smoke (ETS) exposure measures, reviews the empirical evidence of their validity for children's exposure, and discusses future research.

DATA SOURCES

Studies were identified by computer search and from the authors' research.

STUDY SELECTION

Studies were selected for inclusion of nicotine and/or cotinine and quantitative reported measures of ETS exposure.

DATA SYNTHESIS

Five studies found significant associations between reported quantitative exposure of children to ETS and either environmental nicotine or urine cotinine assays. Correlation coefficients between parent reports and nicotine ranged from 0.22 to 0.75. Coefficients for cotinine ranged from 0.28 to 0.71. Correlations increased over time and were stronger for parents' reports of their own smoking as a source of children's exposure than for reports of exposure from others.

CONCLUSIONS

Empirical studies show general concordance of reported and either environmental or biological measures of ETS exposure. Relationships were moderate, and suggest sufficient validity to be employed in research and service programs. Future studies need to identify the differences in types of reported or objective measures, population characteristics, etc, contributing to observed variability in order to understand better the conditions under which more valid reported ETS exposure and other measures can be obtained. Reported and either environmental or biological measures should be used in combination, and existing measures should be directed to interventions that may reduce ETS exposure among children.

Effect of counselling mothers on their children's exposure to environmental tobacco smoke: randomised controlled trial

OBJECTIVE

To test the efficacy of behavioural counselling for smoking mothers in reducing young children's exposure to environmental tobacco smoke.

DESIGN

Randomised double blind controlled trial.

SETTING

Low income homes in San Diego county, California.

PARTICIPANTS

108 ethnically diverse mothers who exposed their children (aged <4 years) to tobacco smoke in the home.

INTERVENTION

Mothers were given seven counselling sessions over three months.

MAIN OUTCOME MEASURES

Children's reported exposure to environmental tobacco smoke from mothers in the home and from all sources; children's cotinine concentrations in urine.

RESULTS

Mothers' reports of children's exposure to their smoke in the home declined in the counselled group from 27.30 cigarettes/week at baseline, to 4.47 at three months, to 3.66 at 12 months and in the controls from 24.56, to 12.08, to 8.38. The differences between the groups by time were significant (P=0.002). Reported exposure to smoke from all sources showed similar declines, with significant differences between groups by time (P=0.008). At 12 months, the reported exposure in the counselled group was 41.2% that of controls for mothers' smoke (95% confidence interval 34.2% to 48.3%) and was 45.7% (38.4% to 53.0%) that of controls for all sources of smoke. Children's mean urine cotinine concentrations decreased slightly in the counselled group from 10.93 ng/ml at baseline to 10.47 ng/ml at 12 months but increased in the controls from 9.43 ng/ml to 17.47 ng/ml (differences between groups by time P=0.008). At 12 months the cotinine concentration in the counselled group was 55.6% (48.2% to 63.0%) that of controls.

CONCLUSIONS

Counselling was effective in reducing children's exposure to environmental tobacco smoke. Similar counselling in medical and social services might protect millions of children from environmental tobacco smoke in their homes.

Reducing children's exposure to environmental tobacco smoke: the empirical evidence and directions for future research

OBJECTIVE

To summarise the issues and empirical evidence for reduction of children's residential environmental tobacco smoke (ETS) exposure.

DATA SOURCES

Literature was obtained by computer search, with emphasis on studies that included quantitative measures of ETS exposure in children's residences and interventions based on social learning theory.

STUDY SELECTION

Review and empirical articles concerning ETS exposure were included and inferences were drawn based on a synthesis of these studies as contrasted with a quantitative meta-analysis.

DATA SYNTHESIS

Interventions designed for residential/child ETS exposure control have included policy/legal regulations, minimal clinical services, and counselling services. Divorce court and adoption services have limited custody to protect children from ETS exposure. Controlled trials of clinicians' one time counselling services have shown null results. One controlled trial found that repeated physician ETS counselling increased parent cessation. Three trials found that repeated counselling/shaping procedures reduced quantitative estimates of ETS exposure in asthmatic children.

CONCLUSIONS

Insufficient controlled studies of repeated session counselling procedures have been completed to determine efficacy for ETS exposure reduction, but evidence is promising. One time minimal interventions appear ineffective, but large scale studies may be warranted. No studies have been conducted to assess court or adoption agency regulations; no community ordinances for regulating residential ETS exposure have been invoked. Ethical and enforcement issues are discussed.

Measuring secondhand smoke exposure in babies: the reliability and validity of mother reports in a sample of low-income families

The reliability and validity of mother's reports of their infants' exposure to secondhand smoke (SHS) were examined in an ethnically diverse sample of low-income, low-education families (N = 141 mothers). At baseline and posttest, smoking mothers reported about their infants' SHS exposure at different locations and by different sources during the previous week. Findings show that mothers can give reliable accounts of the degree to which they contribute to their babies' SHS exposure. Mothers are able to differentiate between their own smoking behavior and the extent to which they expose their infants. Consistent with the overall exposure pattern, exposure caused by the mother and exposure occurring at home showed the strongest associations with biological and environmental measures. These findings suggest that smoking mothers can provide reliable and valid reports of the degree to which their infants are exposed to SHS.

Tobacco use and other risk behaviors: cross-sectional and predictive relationships for adolescent orthodontic patients

BACKGROUND

The purpose of these analyses was to examine the prevalence of selected substance abuse, general and dental health risk, and scholastic risk behaviors and their cross-sectional and predictive relationships with tobacco use among 15, 179 adolescent orthodontic patients in Southern California.

METHODS

Subjects were recruited through 154 orthodontists' offices and interviewed by telephone at baseline and two-year posttest.

RESULTS

Results show a pattern of increasing prevalence of risk behaviors with age. In most cases, gender differences were small. There were statistically significant positive relationships between each risk behavior and tobacco use status for both boys and girls. Prevalence rates of risk behaviors other than tobacco use were highest for current smokers, intermediate for experimenters, and lowest for respondents reporting that they had never used tobacco. Baseline tobacco use predicted each posttest risk behavior in logistic regression analyses. Principle components analysis (with varimax rotation) of posttest risk practices other than tobacco use yielded three theoretically meaningful factors, all which were predicted by baseline tobacco use in multiple regressions.

CONCLUSIONS

These findings show that tobacco use among adolescents can predict subsequent risk practices other than tobacco use as long as two years, and that unhealthy behaviors among teens are interrelated. Orthodontists, who have a high frequency of adolescent patient contact, may be in a unique position to deliver health promotion interventions to their patients; possibly targeting multiple risk behaviors.

Measuring environmental tobacco smoke exposure in infants and young children through urine cotinine and memory-based parental reports: empirical findings and discussion

OBJECTIVE

This study examined the reliability and potential biases of two urine collection methods from which cotinine measures were obtained and the validity of memory-based parental reports of their children's exposure to environmental tobacco smoke (ETS).

DESIGN

Structured interviews were conducted with mothers of infants and young children to obtain memory-based estimates of recent ETS exposure. Urine samples were collected through standard and cotton roll collection methods for cotinine analysis.

SETTING

All interviews took place at an off-campus research facility. Urine samples were collected at the study office or the subjects' homes.

PARTICIPANTS

Mothers were recruited from San Diego county sites of the Women, Infants, and Children (WIC) Supplemental Food and Nutrition Program. Sample 1 (infants) consisted of eight boys and eight girls aged 1-44 months (mean = 12.6 months). Sample 2 (children) included 10 boys and 10 girls aged 3-8 years (mean = 61.2 months).

MAIN OUTCOME MEASURES

Urine cotinine and memory-based parent reports of ETS exposure from structured interviews.

RESULTS

There was overall high reliability for urine cotinine measures and no effect of collection method on urine cotinine levels. Memory-based reports obtained from smoking mothers showed moderately strong and consistent linear relationships with urine cotinine measures of their infants and children (r = 0.50 to r = 0.63), but not for reports obtained from non-smoking mothers.

CONCLUSIONS

Memory-based parental reports of short-term ETS exposure can play an important role in quantifying ETS exposure in infants and children.

Toward a simplified measure of asthma severity for applied research

There is no universally accepted and validated measure of asthma severity. For community research, clinical tests are too costly, and epidemiological assessments provide inadequate data on severity. Symptom measures may offer a practical alternative. This study assessed psychometric properties of symptom ratings of 91 asthmatic children. Reliability and validity of scales created from these items were examined. A sum scale of symptom ratings was internally consistent, reliable across time, and associated with concurrent health indices. This scale may be a practical measure of severity for use in community-based research.

Reduction of environmental tobacco smoke exposure in asthmatic children. A 2-year follow-up

STUDY OBJECTIVE

To examine the long-term maintenance of a previously reported behavioral counseling intervention to reduce asthmatic children's exposure to environmental tobacco smoke (ETS).

PARTICIPANTS

Families of asthmatic children (6 to 17 years), including at least one parent who smoked in the home, recruited from four pediatric allergy clinics.

DESIGN

Participants were randomized to one of three groups: behavioral counseling to reduce ETS exposure, self-monitoring control, and usual medical care control. Counseling concluded at month 6, and the original trial ended at month 12. Two follow-up interviews occurred at months 20 and 30.

MEASUREMENTS AND RESULTS

The originally reported analysis of baseline to 12 months was reanalyzed with a more robust restricted maximum likelihood procedure. The 2-year follow-up period was analyzed similarly. Significantly greater change occurred in the counseling group than the control groups and was sustained throughout the 2 years of follow-up. Further exploratory analyses suggested that printed counseling materials given to all participants at month 12 (conclusion of the original study) were associated with decreased exposure in the control groups.

CONCLUSION

Such long-term maintenance of behavior change is highly unusual in the general behavioral science literature, let alone for addictive behaviors. We conclude that ETS exposure can be reduced and that a clinician-delivered treatment may provide substantial benefit.

Ethnic, socioeconomic, and sex differences in physical activity among adolescents

Regular physical activity is recommended for health maintenance in adolescence, but basic descriptive epidemiological data are lacking for this age group. The present study examined socioeconomic status (SES), ethnic, and sex differences in physical activity in a multiethnic sample of 1871 high school students in San Diego, California. Surveys were completed in required classes by a diverse sample of students from a low-income school district and by Anglo students from a nearby more affluent district. Boys reported more vigorous exercise outside of school and during school physical education, as well as more participation in sports teams, but girls reported taking more activity-related lessons and classes. High-SES students had more frequent physical education classes, spent more time in vigorous exercise in those classes, and participated in more activity lessons outside of school. There were few ethnic differences on summary physical activity or physical education variables. There were no SES differences, but there were ethnic differences on 5 of 22 specific activities. Demographic differences in 25 psychological, social, and environmental variables that may influence physical activity were also examined. Differences between boys and girls were found on several variables, which may explain some of the boys' higher activity levels. Ethnic and/or SES differences were found in 10 of 25 potential correlates of physical activity. These data may be used to identify specific activities that may be preferred by subgroups of adolescents and specific mediating variables that can be targeted in physical activity promotion programs for adolescents.

The accuracy of environmental tobacco smoke exposure measures among asthmatic children

This study determined the reliability and validity of parent-reported measures of environmental tobacco smoke (ETS) exposure among 91 asthmatic children. Test-retest reliability assessments were conducted for environmental, biological and parent-reported measures of ETS exposure. All measures except a urine cotinine assay resulted in satisfactory levels of reliability. The parent-reported measures of ETS exposure were compared to the environmental filter measure of nicotine as well as submitted to a construct validity test. Parent-reported home exposure to ETS proved moderately and significantly correlated to the filter measure. Approximately 80% of all hypothetical constructs agreed with the observed relationships for convergent, divergent and discriminant validity. It was concluded that middle class Caucasian parents' reports of their asthmatic child's residential ETS exposure are reliable and valid. These parent-reported measures should be valuable tools for epidemiological investigations and for clinical programs designed to reduce asthmatic children's residential exposure to ETS.

Parent smoking and asthmatic children's exposure patterns: a behavioral epidemiology study

Exposure of nonsmokers to environmental tobacco smoke (ETS) has become an important public health issue; it is generally agreed that increased exposure is related to morbidity and mortality. Precise prevalence estimates of exposure are not yet available, and measurement methodology for ETS exposure rates is still in its formative stage. Recent interventions have attempted to reduce ETS exposure, particularly in children of smoking parents. Studies have relied primarily upon reduction of parents' smoking rates to indirectly reduce children's ETS exposure. In order to effectively design interventions to achieve reductions in ETS exposure, more attention must be given to smoking behaviors which lead to passive exposure. Ninety-one families with at least one smoking parent and an asthmatic child were recruited from four allergy clinics, and interviewed regarding their smoking history, current residential smoking patterns, and the children's exposure patterns. Descriptive data are presented. It is striking that the most smoking and most exposure did not occur in the same locations, times, or during the same activities. It is recommended that interventions focus closely on these patterns rather than on reduction of smoking rates alone, in order to effect reduction in ETS exposure.

Reduction of environmental tobacco smoke exposure among asthmatic children: a controlled trial

STUDY OBJECTIVE

This randomized clinical trial tested a behavioral medicine program designed to reduce asthmatic children's exposure to environmental tobacco smoke (ETS) in the home.

DESIGN

Families were randomly assigned to an experimental preventive medicine counseling group, a monitoring control group, or a usual treatment control group. Families were measured six times over 1 year.

PARTICIPANTS

Ninety-one families were recruited from four allergy clinics.

INTERVENTION

The experimental group received a 6-month series of counseling sessions designed to decrease ETS exposure. This group also monitored smoking, exposure, and children's asthma symptoms. The monitoring group did not receive counseling and the usual treatment control group received outcome measures only.

MEASUREMENTS AND RESULTS

Parents reported the daily number of cigarettes children were exposed to during the week preceding interviews. A nicotine air monitor and construct validity analysis confirmed the validity of exposure reports. Exposure to the parent's cigarettes in the home decreased for all groups. The experimental group attained a 79 percent decrease in children's ETS exposure, compared with 42 percent for the monitoring control and 34 percent for the usual treatment control group. Repeated-measures analysis of variance resulted in a significant (F([10,350] = 1.92, p < 0.05) group by time effect. At the final 12-month visit, the experimental/counseling group sustained a 51% decrease in children's exposure to cigarettes in the home from all smokers, while the monitoring control group showed an 18% decrease and the usual treatment control group a 15% decrease from pre-intervention [corrected].

CONCLUSION

A behavioral medicine program was successful in reducing exposure to ETS in the home for these asthmatic children.

Correlates of vigorous exercise in a predominantly low SES and minority high school population

BACKGROUND

This study identifies correlates of vigorous exercise among minority and low-socioeconomic-status adolescents.

METHODS

Ninth and 11th grade students completed 1,634 questionnaires regarding vigorous exercise and possible correlates.

RESULTS

While 76% of students participated in vigorous exercise 3 or more times per week (the year 2000 goal for the nation), only 55% participated in vigorous exercise 3 or more times per week outside of school. A substantial minority of students (20%) did not participate in any vigorous exercise outside of school, and 11% did not participate in any vigorous exercise at all. Males and 9th graders participated in significantly more vigorous exercise than did females and 11th graders both in school physical education and outside of school. Hierarchical multiple regression analyses with 28 independent variables were computed separately for males (R = 0.44, F(28,625) = 5.27, P < 0.001) and females (R = 0.45, F(28,622) = 5.56, P < 0.001). Correlates were similar for both groups and included self-efficacy, family, and friend support.

CONCLUSIONS

Results suggest that among minority and lower socioeconomic status adolescents the prevalence of vigorous exercise decreases with age or when students are not required to participate in school physical education and that social factors may be instrumental for sustaining vigorous exercise.