Thirdhand Smoke in the Homes of Medically Fragile Children: Assessing the Impact of Indoor Smoking Levels and Smoking Bans

Contamination of surfaces in children's homes with nicotine and the potent carcinogenic tobacco-specific nitrosamine NNK

BACKGROUND

Tobacco smoke exposure (TSE) through secondhand and thirdhand smoke is a modifiable risk factor that contributes to childhood morbidity. Limited research has assessed surface TSE pollution in children's environments as a potential source of thirdhand smoke exposure, and none have examined levels of the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) on surfaces.

OBJECTIVE

This study measured surface NNK and nicotine in children's homes and associations with sociodemographics and parent-reported TSE behaviors. We assessed correlations of surface NNK and nicotine with dust NNK, dust nicotine, and child cotinine.

METHODS

Home surface wipe NNK and nicotine data from 84 children who lived with smokers were analyzed. Tobit and simple linear regression analyses were conducted to assess associations of surface NNK and nicotine with child characteristics. Spearman's (ρ) correlations assessed the strength of associations between environmental markers and child cotinine.

RESULTS

Nearly half (48.8%) of children's home surfaces had detectable NNK and 100% had detectable nicotine. The respective geometric means (GMs) of surface NNK and nicotine loadings were 14.0 ng/m2 and 16.4 µg/m2. Surface NNK positively correlated with surface nicotine (ρ = 0.54, p < 0.001) and dust NNK (ρ = 0.30, p = 0.020). Surface nicotine positively correlated with dust NNK (ρ = 0.42, p < 0.001) and dust nicotine (ρ = 0.24, p = 0.041). Children with household incomes ≤$15,000 had higher surface NNK levels (GM = 18.7 ng/m2, p = 0.017) compared to children with household incomes >$15,000 (GM = 7.1 ng/m2). Children with no home smoking bans had higher surface NNK (GM = 18.1 ng/m2, p = 0.020) and surface nicotine (GM = 17.7 µg/m2, p = 0.019) levels compared to children with smoking bans (GM = 7.5 ng/m2, 4.8 µg/m2, respectively).

IMPACT

Although nicotine on surfaces is an established marker of thirdhand smoke pollution, other thirdhand smoke contaminants have not been measured on surfaces in the homes of children living with smokers. We provide evidence that the potent carcinogenic tobacco-specific nitrosamine NNK was detectable on surfaces in nearly half of children's homes, and nicotine was detectable on all surfaces. Surface NNK was positively correlated with surface nicotine and dust NNK. Detectable surface NNK levels were found in homes with indoor smoking bans, indicating the role of NNK as a persistent thirdhand smoke pollutant accumulating on surfaces as well as in dust.

Thirdhand smoke beliefs, exposure status and associated factors among young people in China: A cross-sectional study

INTRODUCTION

Thirdhand smoke is an emerging threat to global public health. There is no research on young people's exposure to thirdhand smoke in China. This study aims to investigate the exposure status and beliefs of thirdhand smoke among young Chinese people and provide a reference for policy regarding thirdhand smoke.

METHODS

Data from the 2022 Chinese Resident Psychological and Behavioral Survey were used to select young people aged 15-24 years. A total of 11781 subjects were included in this study. Demographic information, beliefs about thirdhand smoke, and exposure status to thirdhand smoke were investigated.

RESULTS

Among the participants, 47.8% reported being exposed to thirdhand smoke (males: 49.1%, females: 47.0%). Young people living in urban areas (AOR=0.84, 95% CI: 0.77-0.91, p<0.001) and those with a monthly family income >12000 RMB (AOR=0.81, 95% CI: 0.71-0.92, p=0.001) were less likely to be exposed to thirdhand smoke. Young people with junior high school education or higher, and current or former smokers, were more likely to be exposed to thirdhand smoke. There is room for improvement in the beliefs about thirdhand smoke among young people.

CONCLUSIONS

Thirdhand smoke exposure is an issue that should be addressed in public health policy. Young people with low income and current or former smokers are populations that should be mainly focused on in public education and prevention work on thirdhand smoke.

Exposure, Retention, Exhalation, Symptoms, and Environmental Accumulation of Chemicals During JUUL Vaping

Little is known about the chemical exposures that electronic cigarette (EC) users receive and emit during JUUL vaping and if exposures produce symptoms dose dependently. This study examined chemical exposure (dose), retention, symptoms during vaping, and the environmental accumulation of exhaled propylene glycol (PG), glycerol (G), nicotine, and menthol in a cohort of human participants who vaped JUUL "Menthol" ECs. We refer to this environmental accumulation as "EC exhaled aerosol residue" (ECEAR). Chemicals were quantified using gas chromatography/mass spectrometry in JUUL pods before and after use, lab-generated aerosols, human exhaled aerosols, and in ECEAR. Unvaped JUUL "Menthol" pods contained ∼621.3 mg/mL of G, ∼264.9 mg/mL of PG, ∼59.3 mg/mL of nicotine, ∼13.3 mg/mL of menthol, and ∼0.1 mg/mL of the coolant WS-23. Eleven experienced male EC users (aged 21-26) provided exhaled aerosol and residue samples before and after vaping JUUL pods. Participants vaped ad libitum for 20 min, while their average puff count (22 ± 6.4) and puff duration (4.4 ± 2.0) were recorded. The transfer efficiency of nicotine, menthol, and WS-23 from the pod fluid into the aerosol varied with each chemical and was generally similar across flow rates (9-47 mL/s). At 21 mL/s, the average mass of each chemical retained by the participants who vaped 20 min was 53.2 ± 40.3 mg for G, 18.9 ± 14.3 mg for PG, 3.3 ± 2.7 mg for nicotine, and 0.5 ± 0.4 mg for menthol, with retention deduced to be ∼90-100% for each chemical. There was a significant positive relationship between the number of symptoms during vaping and total chemical mass retained. ECEAR accumulated on enclosed surfaces where it could contribute to passive exposure. These data will be valuable to researchers studying human exposure to EC aerosols and agencies that regulate EC products.

Complete home smoking ban survey analysis: an opportunity to improve health equity among sexual minority adults in California, USA

Background

Increasing the proportion of adults living in smoke-free homes is a US Healthy People 2020 objective. Complete home smoking bans are associated with higher odds of smoking cessation attempts and cessation duration. Sexual minority adults have disproportionality higher rates of smoking. This study investigates correlates of having a complete home smoking ban among sexual minority adults in California.

Methods

Secondary data analyses of the California Behavioral Risk Factor Surveillance System (CA BRFSS), 2014–2016. The CA BRFSS telephone survey of adults was conducted in English and Spanish and used random digit dial for landline and cell numbers. Weighted descriptives were stratified by sexual orientation and biological sex. Weighted bivariate and multivariable logistic regression analyses included only sexual minorities (i.e., lesbian, gay, bisexual) and were analyzed as a group and separately by biological sex to account for intragroup variances. The final weighted total of sexual minority adults (N = 359,236) included sexual minority adult females (N = 163,490) and sexual minority adult males (N = 195,746).

Results

Sexual minority adults in California had a lower prevalence of complete home smoking bans (Female 76.2%; Male 75.7%), higher prevalence of current cigarette smoking (Female 23.3%; Male 17.4%) and of e-cigarette use (Female 5.8%; Male 6.4%) than their straight counterparts. Sexual minorities that smoke everyday (Female Adjusted Odds Ratio (AOR) 0.26, 95% Confidence Interval (CI) 0.11–0.63; Male AOR 0.24, 95% CI 0.01–0.56) or some days (Female AOR 0.28, 95% CI 0.09–0.90) had lower adjusted odds of having a complete home smoking ban compared to those who never smoked.

Conclusions

Smoking everyday was the only consistent predictor of not having a complete home smoking ban among sexual minority adults. Focused efforts to increase prevalence of complete home smoking bans should address smoking status to improve health equity among sexual minority adults.

Assessing secondhand and thirdhand tobacco smoke exposure in Canadian infants using questionnaires, biomarkers, and machine learning

BACKGROUND

As smoking prevalence has decreased in Canada, particularly during pregnancy and around children, and technological improvements have lowered detection limits, the use of traditional tobacco smoke biomarkers in infant populations requires re-evaluation.

OBJECTIVE

We evaluated concentrations of urinary nicotine biomarkers, cotinine and trans-3'-hydroxycotinine (3HC), and questionnaire responses. We used machine learning and prediction modeling to understand sources of tobacco smoke exposure for infants from the CHILD Cohort Study.

METHODS

Multivariable linear regression models, chosen through a combination of conceptual and data-driven strategies including random forest regression, assessed the ability of questionnaires to predict variation in urinary cotinine and 3HC concentrations of 2017 3-month-old infants.

RESULTS

Although only 2% of mothers reported smoking prior to and throughout their pregnancy, cotinine and 3HC were detected in 76 and 89% of the infants' urine (n = 2017). Questionnaire-based models explained 31 and 41% of the variance in cotinine and 3HC levels, respectively. Observed concentrations suggest 0.25 and 0.50 ng/mL as cut-points in cotinine and 3HC to characterize SHS exposure. This cut-point suggests that 23.5% of infants had moderate or regular smoke exposure.

SIGNIFICANCE

Though most people make efforts to reduce exposure to their infants, parents do not appear to consider the pervasiveness and persistence of secondhand and thirdhand smoke. More than half of the variation in urinary cotinine and 3HC in infants could not be predicted with modeling. The pervasiveness of thirdhand smoke, the potential for dermal and oral routes of nicotine exposure, along with changes in public perceptions of smoking exposure and risk warrant further exploration.

Duration of breastmilk feeding of NICU graduates who live with individuals who smoke

BACKGROUND

Breast milk has many benefits for infants, but initiating breastfeeding/pumping can be difficult for mothers of preterm infants, especially those who smoke (or live with individuals who smoke). The primary aim of this study was to identify risks for breastfeeding/pumping cessation with neonatal intensive care unit (NICU) infants' mothers who smoke or live with individuals who smoke, using a novel survival-analytic approach.

METHODS/DESIGN

Mothers (N = 360) were recruited for a secondhand smoke prevention intervention during infants' NICU hospitalizations and followed for ~6 months after infant discharge. Data were obtained from medical records and participant self-report/interviews.

RESULTS

The sample was predominantly ethnic/racial minorities; mean age was 26.8 (SD = 5.9) years. One-fifth never initiated breastfeeding/pumping (n = 67; 18.9%) and mean time-to-breastfeeding cessation was 48.1 days (SD = 57.2; median = 30.4 [interquartile range: 6.0-60.9]). Education, length of stay, employment, race/ethnicity, number of household members who smoke, and readiness-to-protect infants from tobacco smoke were significantly associated with breastfeeding cessation. Further, infants fed breast milk for ≥4 months had 42.7% more well-child visits (p < 0.001) and 50.0% fewer respiratory-related clinic visits (p < 0.05).

CONCLUSIONS

One-quarter of infants admitted to NICUs will be discharged to households where individuals who smoke live; we demonstrated that smoking-related factors were associated with mothers' breastfeeding practices. Infants who received breast milk longer had fewer respiratory-related visits.

IMPACT

One-quarter of NICU infants will be discharged to households where smokers live. Initiating/sustaining breastfeeding can be difficult for mothers of preterm NICU infants, especially mothers who smoke or live with others who smoke. Education, employment, race/ethnicity, length of stay, household member smoking, and readiness-to-protect infants from tobacco smoke were significantly associated with time-to-breastfeeding cessation. Infants fed breast milk for ≥4 months had 42.7% more well-child visits and 50.0% fewer respiratory-related clinic visits, compared to infants fed breast milk <4 months. Data support intervention refinements for mothers from smoking households and making NICU-based healthcare workers aware of risk factors for early breastfeeding cessation.

Thirdhand Smoke Contamination and Infant Nicotine Exposure in a Neonatal Intensive Care Unit: An Observational Study

INTRODUCTION

Thirdhand smoke (THS) is ultrafine particulate matter and residue resulting from tobacco combustion, with implications for health-related harm (eg, impaired wound healing), particularly among hospitalized infants. Project aims were to characterize nicotine (THS proxy) transported on neonatal intensive care unit (NICU) visitors and deposited on bedside furniture, as well as infant exposure.

METHODS

Cross-sectional data were collected from participants in a metropolitan NICU. Participants completed a survey and carbon monoxide breath sample, and 41.9% (n = 88) of participants (n = 210) were randomly selected for finger-nicotine wipes during a study phase when all bedside visitors were screened for nicotine use and finger-nicotine levels. During an overlapping study phase, 80 mother-infant dyads consented to bedside furniture-nicotine wipes and an infant urine sample (for cotinine analyses).

RESULTS

Most nonstaff visitors' fingers had nicotine above the limit of quantification (>LOQ; 61.9%). Almost all bedside furniture surfaces (93.8%) and infant cotinine measures (93.6%) had values >LOQ, regardless of household nicotine use. Participants who reported using (or lived with others who used) nicotine had greater furniture-nicotine contamination (Mdn = 0.6 [interquartile range, IQR = 0.2-1.6] µg/m2) and higher infant cotinine (Mdn = 0.09 [IQR = 0.04-0.25] ng/mL) compared to participants who reported no household-member nicotine use (Mdn = 0.5 [IQR = 0.2-0.7] µg/m2; Mdn = 0.04 [IQR = 0.03-0.07] ng/mL, respectively). Bayesian univariate regressions supported hypotheses that increased nicotine use/exposure correlated with greater nicotine contamination (on fingers/furniture) and infant THS exposure.

CONCLUSIONS

Potential furniture-contamination pathways and infant-exposure routes (eg, dermal) during NICU hospitalization were identified, despite hospital prohibitions on tobacco/nicotine use. This work highlights the surreptitious spread of nicotine and potential THS-related health risks to vulnerable infants during critical stages of development.

IMPLICATIONS

THS contamination is underexplored in medical settings. Infants who were cared for in the NICU are vulnerable to health risks from THS exposure. This study demonstrated that 62% of nonstaff NICU visitors transport nicotine on their fingers to the NICU. Over 90% of NICU (bedside) furniture was contaminated with nicotine, regardless of visitors' reported household-member nicotine use or nonuse. Over 90% of infants had detectable levels of urinary cotinine during NICU hospitalizations. Results justify further research to better protect infants from unintended THS exposure while hospitalized.

Tobacco smoke exposure in pediatric cystic fibrosis: A qualitative study of clinician and caregiver perspectives on smoking cessation

OBJECTIVE

Tobacco smoke exposure has negative impacts on the lung health of children with cystic fibrosis (CF), yet evidence-based strategies for smoking cessation have not been tested with or tailored to CF caregivers. This qualitative study identified barriers and facilitators of smoking cessation in this population and outlined potential interventional approaches.

METHODS

We conducted semi-structured interviews with CF familial caregivers who were current or former smokers, and with members of the CF care team. We asked about experiences, practices, and prerequisites for a successful program. Interviews were recorded, transcribed verbatim, and coded by two investigators. Analysis used a thematic approach guided by the PRECEDE model, which identifies predisposing (intrapersonal), reinforcing (interpersonal), and enabling (structural) factors relevant to health behaviors and programs.

RESULTS

Seventeen interviews were conducted-eight with familial caregivers and nine with CF team members. Whereas caregivers provided greater insight into internal difficulties and motivators to quit smoking, clinicians offered more extensive input on barriers and solutions related to the clinical environment. Based on study recommendations, a successful tobacco cessation program should include (a) family education about the harms of smoke exposure for children with CF; (b) screening for exposure, ideally with biochemical verification; (c) access to trained tobacco counselors; (d) affordable pharmacotherapy; and (e) outpatient follow-up of those undergoing tobacco treatment.

CONCLUSION

This qualitative study revealed intrapersonal, interpersonal, and structural barriers to eliminating tobacco smoke exposure in children with CF, outlined opportunities to address these barriers, and made recommendations for a comprehensive tobacco cessation strategy.

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.

Secondhand Smoke From Multiple Sources, Thirdhand Smoke and Respiratory Symptoms in Hong Kong Adolescents

Introduction

Reports on involuntary tobacco smoke exposure in children have focused mostly on secondhand smoke (SHS) from smoking inside the home. We studied the separate and combined prevalence of SHS exposure from multiple sources and thirdhand smoke (THS) and the associations with respiratory symptoms in Hong Kong adolescents.

Methods

In 2010-2011, 61 810 Secondary 1 (US Grade 7) to seven students reported their smoking status, respiratory symptoms, and exposure to four sources of tobacco smoke in the past 7 days. Weighted prevalence of exposure was calculated. Associations with respiratory symptoms were analyzed in 50 762 never smokers using logistic regression.

Results

Tobacco smoke exposure at home was 23.2% considering SHS exposure from inside the home, but increased to 33.2% including SHS from neighbors and 36.2% further including THS. Including SHS outside home (55.3%), 63.3% of adolescents were exposed to SHS anywhere or THS at home. In never smokers, SHS from each source and THS at home were linearly associated with respiratory symptoms. Exposure to more sources yielded stronger associations with respiratory symptoms (p for trend<.001). The adjusted odds ratios (95% CI) were 1.04 (0.97-1.11), 1.12 (1.03-1.22), 1.40 (1.26-1.56) and 1.99 (1.74-2.28) for 1, 2, 3, and 4 sources, respectively.

Conclusions

Although Hong Kong's smoking prevalence is among the lowest in the developed world, over 60% of its adolescents were involuntarily exposed to tobacco smoke from one or more sources with a linear association with respiratory symptoms in never smokers. More stringent policies are needed to protect adolescents from tobacco smoke.

Implications

In a high-density urban setting, involuntary exposure to tobacco smoke in adolescents can be much higher than the smoking prevalence of the general population, especially if SHS exposure from multiple sources and THS are also considered. Such exposures have important health implications as demonstrated by their linear associations with respiratory symptoms. Tobacco control measures effective in reducing smoking prevalence may have little effect in reducing adolescent exposure to tobacco smoke, especially in the private home, in which other public health strategies are urgently needed.

Medical staff contributions to thirdhand smoke contamination in a neonatal intensive care unit

INTRODUCTION

Non-smoking policies are strictly enforced in neonatal intensive care units (NICUs), which may still become contaminated by thirdhand smoke (THS), posing potential health risks to medically fragile infants. Study aims were to explore contamination routes by characterizing nicotine levels (THS proxy) found on the fingers of NICU medical staff and to assess finger-nicotine correlates.

METHODS

NICU medical staff were surveyed regarding smoking and electronic nicotine devices (ENDS) use/exposure, and household characteristics. Approximately 35% of staff were randomly selected for a finger-nicotine wipe. Three separate quantile regressions modeled percentiles associated with: presence of any finger nicotine, finger-nicotine levels above the median field blank level (i.e. 0.377 ng/wipe), and finger-nicotine levels two times the median blank.

RESULTS

The final sample size was 246 (n=260 approached; n=14 refusals). Over three-quarters (78.5%) reported some exposure to tobacco smoke or ENDS vapor/aerosols. After field-blank adjustments, the median nicotine level (ng/finger wipe) was 0.232 (IQR: 0.021–0.681) and 78.3% of medical staff had measurable finger-nicotine levels. Both being near smoking in friends’/family members’ homes and finger-surface area were related to elevated finger-nicotine levels (p<0.05) in the median blank model.

CONCLUSIONS

Almost four in five NICU staff had measurable finger nicotine, with finger surface area and frequency of reported exposure to tobacco smoke in friends’/family members’ homes emerging as important correlates. Future research will determine the impact of THS on NICU infants. Medical personnel working in a NICU should be cognizant of secondhand smoke and THS, particularly inside friends’/family members’ homes, to reduce potential NICU contamination and infant exposures.

Nicotine on Children's Hands: Limited Protection of Smoking Bans and Initial Clinical Findings

Background:

Thirdhand smoke (THS) pollutants, such as nicotine, accumulate on the hands of children who live in homes with smokers and are exposed to secondhand smoke. Our objective was to examine whether levels of hand nicotine in exposed children are associated with demographics, environmental factors, and clinical findings.

Methods:

Participants were caregivers who smoke and children (mean age (SD) = 2.6 (3.7) years) who were part of an ongoing 2-group, randomized controlled trial of an emergency department–based tobacco cessation intervention (N = 104). The primary outcome measure was nicotine on the child’s hand. Caregivers reported demographics and smoking patterns; children’s medical records were abstracted for chief complaint, medical history, and diagnoses.

Results:

All children had detectable hand nicotine (geometric mean [GeoM] = 86.2 ng/wipe; range = 3.5-2, 190.4 ng/wipe). Children in the age group of 2 to 4 years old (GeoM = 185.6 ng/wipe) had higher levels than the children in the age groups of 0 to 1 (GeoM = 68.9 ng/wipe, P < .001), 5 to 9 (GeoM = 77.9 ng/wipe, P = .04), and 10 to 15 years old (GeoM = 74.2 ng/wipe, P = .048). Children whose caregivers smoked 6 to 14 (GeoM = 97.2 ng/wipe, P = .047) and 15 to 40 cigarettes/day (GeoM = 124.0 ng/wipe, P = .01) had higher levels than children whose caregivers smoked 1 to 5 cigarettes/day (GeoM = 59.7 ng/wipe). Children with 6 to 14 cigarettes/day (GeoM = 163.11 ng/wipe, P = .007) and 15 to 40 cigarettes/day (GeoM = 186.1, P = .003) smoked inside the home by all smokers had significantly higher levels than homes with 0 cigarettes (GeoM = 81.3 ng/wipe). Similar differences in hand nicotine levels were found for smoking frequency of all household members in any location. Children with complaints of cough/congestion (GeoM = 97.7 ng/wipe) had higher levels than those without cough/congestion (GeoM = 59.0 ng/wipe, P = .01).

Conclusions:

The high hand nicotine levels in children whose caregivers do not necessarily smoke indoor demonstrate that indoor smoking bans do not safeguard against THS exposure and the associations with increased home smoking activity indicate that hand wipes may be a noninvasive way to characterize children’s exposure. The findings of associated cough and congestion with higher THS levels need to be examined further.

Update on thirdhand smoke: A comprehensive systematic review

OBJECTIVE

The objective of this study is to perform a comprehensive review of the literature about thirdhand smoke (THS).

METHODS

Systematic review of all aspects of THS. Standard methodological procedures were used to search the following databases through April 2018: MEDLINE, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science (WOS) in Indo-European languages. To identify published grey literature, the first 200 hits from Google Scholar™ were evaluated. Clinical trial databases, conference proceedings, and reference lists from the identified articles were also searched. Two unblinded review authors independently assessed trials for inclusion in the review. These same reviewers also extracted study data in accordance with PRISMA guidelines. The study protocol was registered with PROSPERO (CRD42018083619).

RESULTS

Sixty-eight articles were included in this systematic review. Of these, 28 analyzed the concentration of nicotine as a component of THS (the most commonly-used method to measure THS in those studies was chromatography, followed by the mass spectrometry), 21 evaluated the exposure and impact of THS on health (11 studies analyzed the effect of THS in cells [human and animal], 4 in animals, 1 in adults, and 5 in children), 16 investigated the beliefs, behaviours, and policies related to THS, and 3 evaluated other aspects such as THS in e-cigarettes or hookahs. In these 68 studies, THS was determined by measuring the following components: nicotine (30 studies), nitrosamines (17 studies) and cotinine (15 studies). The findings from most of these studies suggest a potential health impact of THS exposure (i.e.: cytotoxicity, metabolic alterations in metabolism, in glycemia; or cell structure; alterations in liver, lung, skin and behaviour in mice), and low awareness about the risks of THS among the general population.

CONCLUSIONS

Numerous specific biomarkers of THS were evaluated, with the most common being nicotine, nitrosamines, and cotinine. The most common method of preparing THS dust samples were cotton wipes, while chromatography, used alone or coupled with mass spectrometry, was the most common analytical technique. We have tried to establish common bases after reviewing all the current literature of the THS although, there is great heterogeneity between the studies and we have not always succeeded. The studies in this review demonstrate the harmful effects of THS on health in cells, in animal models, and in people including children. However, in people, the long-term effects remain unknown and more research is needed. These studies show that knowledge about THS and its potential harmful effects are poorly understood among the general population. For this reason, THS should receive greater emphasis in education and awareness policies.

Exposure to third-hand smoke during pregnancy may increase the risk of postpartum depression in China

INTRODUCTION

Our aim was to investigate the association between third-hand smoke exposure (THS) during pregnancy and postpartum depression (PPD) among Chinese women.

METHODS

A total of 973 participants that completed the questionnaire and reviews were included in this cross-sectional study. The THS exposure was assessed based on a questionnaire with key questions from the Global Adult Tobacco Survey (2nd edition) while postpartum depression status was assessed using the Edinburgh Postnatal Depression Scale. Logistic regression models were used to estimate the association between THS exposure during pregnancy and risk of PPD, after adjustment for potential confounders.

RESULTS

The prevalence of postpartum depression among all participants was 17.8%. Of the 973 participants, 725 (74.5%) were exposed to THS during pregnancy while 248 (25.5%) were not. Compared with those who were never exposed to passive smoking, puerperal women who were exposed to THS were at higher risk of PPD (OR=1.71, 95% CI: 1.12-2.60) in the logistic regression model.

CONCLUSIONS

Our study suggests that exposure to third-hand smoke may be a risk factor for postpartum depression among Chinese women. Future preventive interventions should include strategies that target the puerperal women who are exposed to THS during pregnancy. Tobacco control measures that are effective in reducing the prevalence of smoking may have little effect in reducing women's exposure to THS during pregnancy, especially in private places that urgently need other public health strategies.

Guidance for the Clinical Management of Thirdhand Smoke Exposure in the Child Health Care Setting

OBJECTIVE

To explain the concept of thirdhand smoke and how it can be used to protect the health of children and improve delivery of tobacco control interventions for parents in the child health care setting.

METHODS

Review of the literature and descriptive report.

RESULTS

The thirdhand smoke concept has been used in the CEASE intervention to improve the delivery of tobacco control counseling and services to parents. Materials and techniques have been developed for the child health care setting that use the concept of thirdhand smoke. Scientific findings demonstrate that thirdhand smoke exposure is harmful and establishes the need for clinicians to communicate the cessation imperative: the only way to protect non-smoking household members from thirdhand smoke is for all household smokers to quit smoking completely. As the scientific knowledge of thirdhand smoke increases, advocates will likely rely on it to encourage completely smoke-free places.

CONCLUSION

Recent scientific studies on thirdhand smoke are impelling further research on the topic, spurring the creation of tobacco control policies to protect people from thirdhand smoke and stimulating improvements to the delivery of tobacco control counseling and services to parents in child health care settings.

Medication use, sleep, and caregiver smoking status among urban children with asthma

OBJECTIVE

Children living in urban settings from low-income, minority families are at a high risk for experiencing asthma morbidity. Environmental tobacco smoke (ETS, i.e., secondhand) exposure, typically from caregiver smoking, has been associated with increased quick-relief medication use and child nocturnal awakenings due to increased asthma symptoms as well as worse sleep quality in children with asthma. This study investigated the moderating role of caregiver smoking status on the association between quick-relief medication use and child's sleep quality in urban children with persistent asthma.

METHODS

Fifty-four urban children with persistent asthma and their primary caregivers completed a baseline research session. Caregivers then completed ecological momentary assessment surveys via smartphones twice daily for two weeks in which smoking behaviors, child quick-relief medication use, and child's sleep quality were assessed.

RESULTS

Twenty caregivers (37%) reported smoking at least one day across the two-week period. The caregiver smoking status significantly moderated the association between quick-relief medication use and child's sleep quality after controlling for child age and monthly household income. The caregiver smoking status exacerbated the association between quick-relief medication use and child's sleep quality, such that more medication usage was associated with worse sleep quality.

CONCLUSIONS

Findings suggest that in urban families with a caregiver who smokes, more daily quick-relief medication use may put children at an increased risk for worse sleep quality. The effects of ETS exposure on child's sleep quality in addition to child asthma symptoms should be an integral part of discussions between pediatric healthcare providers and families of children with asthma.

Preliminary evidence that high levels of nicotine on children's hands may contribute to overall tobacco smoke exposure

BACKGROUND

Dust and surfaces are important sources of lead and pesticide exposure in young children. The purpose of this pilot study was to investigate if third-hand smoke (THS) pollutants accumulate on the hands of children who live in environments where tobacco is used and if hand nicotine levels are associated with second-hand smoke (SHS), as measured by salivary cotinine.

METHODS

Participants were parents and children (n=25; age mean (SD)=5.4 (5.3) years) presenting to the emergency department with a potentially SHS-related illness. A convenience sample of participants were recruited at baseline from an ongoing two-group, randomised controlled trial of a SHS reduction and tobacco cessation intervention. Parents were current smokers; thus, all children were at risk of SHS and THS exposure to varying extents. Primary outcome measures, which were assessed in child participants only, were hand nicotine and salivary cotinine. Parents reported sociodemographics and smoking patterns; children's medical records were abstracted for chief complaint, medical history and discharge diagnosis.

RESULTS

All children had detectable hand nicotine (range=18.3-690.9 ng/wipe). All but one had detectable cotinine (range=1.2-28.8 ng/mL). Multiple linear regression results showed a significant positive association between hand nicotine and cotinine (p=0.009; semipartial r²=0.24), independent of child age.

DISCUSSION

The higher-than-expected nicotine levels and significant association with cotinine indicate that THS may play a role in the overall exposure of young children to tobacco smoke toxicants and that hand wipes could be a useful marker of overall tobacco smoke pollution and a proxy for exposure.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Identifier: NCT02531594.

Thirdhand smoke: when the danger is more than you can see or smell

Recent discussion has focused on another form of exposure to tobacco - thirdhand smoke (THS) - consisting of residual pollutants from cigarette smoke that remain in environments. The main concern with THS is based on the presence and persistence of many toxic compounds, some specific nitrosamines from tobacco that have carcinogenic activity. Little is known about THS, and few people are aware of its existence and potential health repercussions, thus highlighting the need to shed light on the subject and incorporate it into the public health debate, as was done with passive smoking several years ago. THS is a form of passive smoking, together with secondary or involuntary exposure to cigarette smoke. Recentemente, passou a ser discutida mais uma forma de exposição ao tabaco - thirdhand smoke (THS) - que consiste nos poluentes residuais da fumaça de cigarro que permanecem nos ambientes. A principal preocupação com o THS é embasada na presença e longa persistência de muitos compostos tóxicos, algumas nitrosaminas específicas do tabaco que têm atividade carcinogênica. Além de se saber pouco sobre o THS, poucos sabem de sua existência e preocupante repercussão na saúde. Coloca-se em destaque a necessidade de trazê-lo à luz e incluí-lo nas discussões, assim como foi feito com o tabagismo passivo alguns anos atrás, até mesmo porque o THS se caracteriza como uma forma de tabagismo passivo junto à exposição secundária ou involuntária da fumaça de cigarro.

Understanding motivation to implement smoking bans among mothers with a hospitalized infant

OBJECTIVE

Secondhand smoke exposure (SHSe) poses risks to hospitalized children upon discharge and no uniformly effective interventions have been identified. Understanding change-related processes and social-contextual factors related to motivation for implementing home and car smoking bans may inform interventions to reduce infant SHSe among mothers with a hospitalized infant.

METHODS

In this cross-sectional, secondary analysis, mothers of neonatal ICU infants who reported smoking or living with a smoker (N=205) were assigned to stages of change (pre-contemplation, contemplation, preparation, or action) based on behaviors and intentions for establishing smoking bans in their homes and cars. Processes of change (POC) for SHSe reduction practices, self-efficacy, depressive symptoms, generalized anxiety, and social support for not smoking in the home were examined across all four stages.

RESULTS

The majority of mothers were in the action stage for having a home smoking ban in place (55%); only 35% of participants were in action for a car smoking ban. POC use differed across the stages of change for having a home ban (p=0.004) and car ban (p=0.02), with earlier stages using fewer overall and relatively fewer cognitive/affective processes. Earlier stage women also reported lower self-efficacy to change, less familial and partner support for in-home smoking bans, and more depressive symptoms.

CONCLUSIONS

Novel intervention targets were identified, including cognitive/affective change processes, mental health, and familial/social contingencies for implementing SHSe protective practices. Creative ways in which to affect change at the individual and household level are needed in order to fully address the complexity of child SHSe.

Thirdhand smoke contamination in hospital settings: assessing exposure risk for vulnerable paediatric patients

BACKGROUND

Tobacco has regained the status of the world's number two killer behind heart/vascular disease. Thirdhand smoke (THS) residue and particles from secondhand smoke (SHS) are suspected health hazards (eg, DNA damage) that are likely to contribute to morbidity and mortality, especially in vulnerable children. THS is easily transported and deposited indoors, where it persists and exposes individuals for months, creating potential health consequences in seemingly nicotine-free environments, particularly for vulnerable patients. We collected THS data to estimate infant exposure in the neonatal ICU (NICU) after visits from household smokers. Infant exposure to nicotine, potentially from THS, was assessed via assays of infant urine.

METHODS

Participants were mothers who smoked and had an infant in the NICU (N=5). Participants provided surface nicotine samples from their fingers, infants' crib/incubator and hospital-provided furniture. Infant urine was analysed for cotinine, cotinine's major metabolite: trans-3'-hydroxycotinine (3HC) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), a metabolite of the nicotine-derived and tobacco-specific carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK).

RESULTS

Incubators/cribs and other furniture had detectable surface nicotine. Detectable levels of cotinine, 3HC and NNAL were found in the infants' urine.

DISCUSSION

THS appears to be ubiquitous, even in closely guarded healthcare settings. Future research will address potential health consequences and THS-reduction policies. Ultimately, hospital policies and interventions to reduce THS transport and exposure may prove necessary, especially for immunocompromised children.