Thirdhand Smoke Exposure Research Articles

Perceived Health Concerns of Child Thirdhand Smoke Exposure and Potential Remediation Strategies Among Nonsmoking Parents of Young Children

Perceived Health Concerns of Child Thirdhand Smoke Exposure and Potential Remediation Strategies Among Nonsmoking Parents of Young Children

Long-term exposure to third-hand smoke could accelerate biological aging via mitochondrial dysfunction: Evidence from population and animal studies

The relationship between third-hand smoke (THS) exposure and lifespan remains inadequately explored. Our study sought to clarify the effects of THS on aging and lifespan. In this pursuit, our cross-sectional analysis assessed hematological aging markers in 986 non-smokers and examined lifespan alterations using a Drosophila model. THS exposure levels were quantified through survey metrics consistent with the Global Adult Tobacco Survey. The findings revealed that THS exposure significantly accelerated biological aging, with exposed individuals exhibiting an average increase in biological age of 3.04 years compared to their unexposed counterparts (p < 0.05). Correspondingly, the Drosophila model reflected these outcomes, showing a reduction in lifespan by 16.07 days (p < 0.01). Proteomic analyses identified MRPL2 as a pivotal protein in THS-induced aging, linking its expression to mitochondrial dysfunction and oxidative stress. Further metabolomic profiling highlighted disruptions in energy metabolism pathways. Follow-up in vitro experiments confirmed the role of MRPL2 in the aging processes at the cellular level. Overall, our results indicate that THS exposure is a significant accelerant of aging, providing new perspectives on the health consequences of environmental smoke residues.

Tobacco use, secondhand exposure and knowledge of secondhand and third-hand smoke among medical college students in Western Nepal: a cross-sectional study

ObjectivesThis study was conducted to assess the prevalence of tobacco use, secondhand smoke (SHS) exposure and knowledge about SHS and third-hand smoke (THS) exposure among students in a medical college...

Thirdhand Smoke Exposure Ignored by Pediatricians: A Cross-sectional Study.

Thirdhand smoke (THS) is defined as the harmful substances in cigarette smoke that are absorbed into objects, people, and surfaces after smoking. This study aimed to determine the level of awareness of pediatricians working in a tertiary healthcare institution about THS exposure. In this cross-sectional study, participants were asked to fill out an information form in which we questioned the participant's age, sex, occupation in the institution, the exposure of pediatric patients to cigarette smoke during daily healthcare, tobacco product use status, smoking status in their home and car, behavior in case of smoking in closed areas where smoking is prohibited, and whether they knew the term of THS. Also, the Turkish version of The Beliefs About Third-Hand Smoke was used. Eighty-one participants, with a mean age of 34.2 ± 7.6 years, were included in the study. Fifty-six (69.1%) participants said they had never used tobacco products. Participants who had never used tobacco products (P = .005), never allowed smoking in their homes (P = .017) and cars (P = .001), had heard the definition of THS before (P = .013), and thought they knew it (P = .005) had higher total scale scores. There was no significant difference between the THS awareness levels of pediatricians who questioned children's exposure to cigarette smoke in their daily practice and those who did not (P = .491). Determining the awareness levels of pediatricians about THS will be an important step in preventing THS exposure in children.

Thirdhand smoke exposure promotes gastric tumor development in mouse and human

The pollution of indoor environments and the consequent health risks associated with thirdhand smoke (THS) are increasingly recognized in recent years. However, the carcinogenic potential of THS and its underlying mechanisms have yet to be thoroughly explored. In this study, we examined the effects of short-term THS exposure on the development of gastric cancer (GC) in vitro and in vivo. In a mouse model of spontaneous GC, CC036, we observed a significant increase in gastric tumor incidence and a decrease in tumor-free survival upon THS exposure as compared to control. RNA sequencing of primary gastric epithelial cells derived from CC036 mice showed that THS exposure increased expression of genes related to the extracellular matrix and cytoskeletal protein structure. We then identified a THS exposure-induced 91-gene expression signature in CC036 and a homologous 84-gene signature in human GC patients that predicted the prognosis, with secreted phosphoprotein 1 (SPP1) and tribbles pseudokinase 3 (TRIB3) emerging as potential targets through which THS may promote gastric carcinogenesis. We also treated human GC cell lines in vitro with media containing various concentrations of THS, which, in some exposure dose range, significantly increased their proliferation, invasion, and migration. We showed that THS exposure could activate the epithelial-mesenchymal transition (EMT) pathway at the transcript and protein level. We conclude that short-term exposure to THS is associated with an increased risk of GC and that activation of the EMT program could be one potential mechanism. Increased understanding of the cancer risk associated with THS exposure will help identify new preventive and therapeutic strategies for tobacco-related disease as well as provide scientific evidence and rationale for policy decisions related to THS pollution control to protect vulnerable subpopulations such as children.

First, second and third-hand smoke exposure during pregnancy - Τhe adverse effects on the fetus: A Systematic Review

First, second and third-hand smoke exposure during pregnancy - Τhe adverse effects on the fetus: A Systematic Review

Prevalence of Second-hand and Third-hand Smoke Exposure among the Medical and Dental Students

Prevalence of Second-hand and Third-hand Smoke Exposure among the Medical and Dental Students

Sex-Dependent Occlusive Cardiovascular Disease Effects of Short-Term Thirdhand Smoke Exposure.

Thirdhand smoke (THS) is associated with many public health and disease concerns, such as respiratory illness, cancer, lipidemia, and cardiovascular disease (CVD). We have previously shown that a moderate to long-term exposure to THS increases the risk of thrombosis. However, whether short-term exposure to THS would produce any effects remains to be discovered. Therefore, this study investigated the impact of 1-month THS exposure on platelet function, in vivo and in vitro, and on cytokine response, in a sex-dependent manner. Secondhand smoke or clean air (CA) exposed upholstery materials for 1 week were kept in cages housed with 5-6 mice, and the procedure was repeated for 4 weeks. These THS-exposed mice were evaluated for thrombogenesis and platelet function assays. In addition, cytokines expression was evaluated from pooled serum. Compared to the CA group, THS exposure significantly shortened the tail bleeding time and carotid artery thrombus formation. Moreover, the female mice appeared more sensitive to THS exposure than males. Furthermore, platelet aggregation, dense granule secretion, and P-selectin activation markers were significantly elevated due to THS exposure. In addition, high-throughput screening showed at least 30 cytokines differentially modulated by THS in females relative to 26 in male mice. Collectively, these results demonstrate that 1 month of THS exposure represents a high health risk, in part, by triggering a prothrombotic phenotype that appears to be more significant in females, who are at a much higher risk for occlusive CVD. Additionally, changes in cytokine levels mediate some of the THS-induced occlusive effects. This study revealed that THS exposure for 1 month is detrimental to the cardiovascular health of both sexes; however, females could be more aggressively affected than males. In addition, interleukins and chemokines could be critical factors for initiating prothrombotic activity due to THS exposure.

Intentions to Use Cannabis Postpartum: A Qualitative Study of Pregnant Individuals Who Used Cannabis During Early Pregnancy.

Objective: To examine plans for postpartum cannabis use among pregnant individuals who used cannabis during early pregnancy. Materials and Methods: Eighteen virtual focus groups were conducted from November 17, 2021, to December 17, 2021, with 23 Black and 30 White pregnant adults in Kaiser Permanente Northern California, who self-reported prenatal cannabis use during early pregnancy. Focus groups were recorded, transcribed, and analyzed using thematic analysis. Results: The sample (N = 53) had a mean age of 30.3 years (standard deviation = 5.2) at recruitment; 70% reported daily, 25% weekly, and 6% ≤ monthly cannabis use at entrance to prenatal care. Some participants viewed cannabis as critical for coping with postpartum mental and physical health challenges, while others questioned whether cannabis use would fit with their parental lifestyle, and some planned to abstain altogether. Most planned to use cannabis postpartum, but with lower frequency than before pregnancy, and in ways consistent with harm reduction (e.g., smoking outside to avoid secondhand or thirdhand smoke exposure). Many were motivated to abstain from cannabis while breastfeeding, and some desired more data on the safety of cannabis and breastfeeding, or intended to "pump and dump," believing it would reduce potential transfer of Δ9-tetrahydrocannabinol (THC) to their infant. Responses from Black and White participants were generally similar, but White participants were more likely to report plans to use cannabis while breastfeeding and to want information about cannabis and breastfeeding. Conclusions: Pregnant individuals with prenatal cannabis use had varied plans for cannabis use postpartum. Many were motivated to abstain or use cannabis less frequently than pre-pregnancy, especially during lactation.

The association between passive smoking and sleep quality in a Chinese hypertensive population: A cross-sectional study.

This study evaluates the association between passive smoking, specifically secondhand smoke (SHS) and thirdhand smoke (THS) exposure, and sleep quality in a hypertensive population. We enrolled 1427 eligible hypertensive patients from a 2022 national cross-sectional survey in China. Data on tobacco smoke exposure and sleep were collected via questionnaires. Multiple logistic regression and linear regression were employed to assess the relationship between passive smoking and sleep quality characteristics, as well as the correlation between passive smoking exposure characteristics and sleep quality. Among 589 hypertensive patients with no tobacco smoke exposure, 679 exposed to SHS, and 159 exposed to THS, SHS exposure was associated with a higher risk of poor sleep quality, even after adjusting for potential confounding factors (β=0.10; 95% CI: 0.32-0.95). No significant relationship was observed between THS exposure and sleep quality. SHS exposure was associated with various sleep quality characteristics, including shorter sleep duration (AOR=1.71; 95% CI: 1.06-2.76) and increased frequency of 1-2 sleep disturbances per week (AOR=1.68; 95% CI: 1.25-2.26). Individuals exposed to SHS were more likely to experience poorer subjective sleep quality (AOR=1.53; 95% CI: 1.07-2.21) and have sleep efficiency <65% (AOR=1.82; 95% CI: 1.22-2.71). Exposure to passive smoking at home, in the community, in public places, exposure to passive smoking with family and friends, and increased frequency of exposure, were all associated with a higher risk of poor sleep quality. Our study suggests that SHS exposure in hypertensive populations is associated with poor sleep quality and various characteristics of sleep quality. No significant association was found between THS exposure and sleep quality. These findings underscore the need to enhance tobacco control efforts in China, particularly for individuals with chronic diseases, to safeguard public health.

Dermal thirdhand smoke exposure induced epidermal alterations in human keratinocyte cells through oxidative damage and MMP-1 expression.

Thirdhand smoke (THS) is the residual cigarette smoke that settles on indoor surface fabrics, dust and can accumulate in the environment. Therefore, it can be a risk factor for individuals who have frequent dermal contact with THS-contaminated surfaces. In the present study, it was aimed to elucidate the toxicity of dermal THS exposure in HaCaT human keratinocytes. The THS was extracted from terrycloth exposed to 3R4F research cigarette smoke in a closed chamber and the adverse outcomes induced by THS were determined through assessment of cytotoxicity tests (MTT and NRU), intracellular GSH level, total SOD activity, matrix metalloproteinase-1 (MMP-1) and IL-6 levels. The wound healing capacity of THS-exposed keratinocytes was evaluated via scratch assay. A potent antioxidant isothiocyanate compound, sulforaphane (SFN), was used as a negative control. THS was dose-dependently cytotoxic (12.5%-100%, v/v) to the HaCaT cells through mitochondrial cell dysfunction (p < 0.01), which was ameliorated by SFN (0.62 μM) pre-treatment. In parallel, THS exposure significantly decreased the intracellular GSH deposits and T-SOD activity in keratinocytes. Collagen degradation through elevated MMP-1 expression was observed in THS-exposed cells in parallel with the delay of wound healing and increased pro-inflammatory response in a dose-dependent manner (p < 0.05). The findings are expected to raise awareness about THS as an environmental pollutant for skin, particularly in the highest-ranked countries in cigarette consumption. To conclude, these results might contribute to the studies on the importance of dermal exposure to THS in the pathogenesis of epidermal alterations and the other skin diseases.

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

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. 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. 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. 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). 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 vaping exposures are associated with pulmonary and systemic inflammation in a mouse model.

Thirdhand smoke (THS) is the accumulation of secondhand smoke on surfaces that ages with time. THS exposure is a potential health threat to children, partners of smokers, and workers in environments with current or past smoking, and needs further investigation. In this study, we hypothesized that thirdhand Electronic Nicotine Delivery Systems (ENDS) exposures elicit lung and systemic inflammation due to resuspended particulate matter (PM) and inorganic compounds that remain after active vaping has ceased. To test our hypothesis, we exposed C57BL/6J mice to cotton towels contaminated with ENDS aerosols from unflavored vape fluid (6 mg nicotine in 50/50 propylene glycol/vegetable glycerin) for 1h/day, five days/week, for three weeks. We assessed protein levels in serum and bronchoalveolar lavage fluid (BALF) using a multiplex protein assay. The mean ± sd for PM10 and PM2.5 measurements in exposed mouse cages were 8.3 ± 14.0 and 4.6 ± 7.5 μg/m3, compared to 6.1 ± 11.2 and 3.7 ± 6.6 μg/m3 in control cages respectively. Two compounds, 4-methyl-1, 2-dioxolane and 4-methyl-cyclohexanol, were detected in vape fluid and on ENDS-contaminated towels, but not on control towels. Mice exposed to ENDS-contaminated towels had lower levels of serum Il-7 (P = 0.022, n = 7), and higher levels of Il-13 in the BALF (P = 0.006, n = 7) than those exposed to control towels (n = 6). After adjusting for sex and age, Il-7 and Il-13 levels were still associated with thirdhand vaping exposure (P = 0.010 and P = 0.017, respectively). This study provides further evidence that thirdhand ENDS aerosols can contaminate surfaces, and subsequently influence lung and systemic health upon exposure.

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

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. 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. 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. 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.

Promoting Smoke-Free Environments: The Impact of Thirdhand Smoke Awareness on Smoking Bans at Home.

A creating smoke-free home is a way to protect a vulnerable group from being exposed to secondhand smoke in the home, such as children, infants, and non-smokers. Studies reported an intervention for promoting a smoke-free home by using secondhand smoke messages and smoking cessation messages. However, the thirdhand smoke (THS) message has rarely been found. Therefore, this study aimed to explore the prevalence and correlations of smoking bans in homes. Secondary data from a community-based cross-sectional design survey was used for this study. Smoking ban status was defined as a smoking ban or no smoking ban. We used multiple logistic regression to test the association between factors and smoking ban status. An adjusted odd ratio and 95% confidence interval were reported. Of the 882 participants included in this analysis, 38.66% (95%CI: 35.43, 41.97) had a smoking ban at home. A multiple logistic regression analysis showed that participants who believe that secondhand or THS harms children had a greater correlation with developing a smoking ban in the home compared with those who did not believe (odd ratio: 3.94, 95% confidence interval: 2.35, 6.60 and odd ratio:4.22, 95% confidence interval:2.6, 6.86, respectively). This study found that the belief that thirdhand smoke and secondhand smoke exposure harm children. The smoke-free home message's relevance to the harms of thirdhand smoke exposure should be adapted to be promoted, especially in homes.

EVALUATION OF THIRD HAND CIGARETTE SMOKE EXPOSURE AND AWARENESS IN UNIVERSITY STUDENTS

ABSTRACT&#x0D; Background:Third Hand Smoke (THS) is tobacco dust that settles in the environment after smoking. It combines with other pollutants in the air and diffuses back into the air. It can enter the systemic circulation by inhalation, absorption through the skin, and ingestion of tobacco dust-contaminated objects. It cannot be completely eliminated by ventilating and cleaning the environment. Exposure to THS negatively affects the health of all people, especially infants and children. The aim of the study is to reveal THS exposure and awareness in 6th grade students of Ankara Yıldırım Beyazıt University Faculty of Medicine and the factors associated with it.&#x0D; Methods and Results: As a data collection tool, a questionnaire consisting of a Beliefs About Third Hand Smoke (BATHS-T) Scale was prepared to recognize sociodemographic data form, smoking status, tobacco control policies, smoking bans at home and in the car, attitudes towards buying / renting a house / car, and THS awareness. Using an online survey, 322 people were reached. &#x0D; Conclusions: The mean BATHS-T (total) score of the participants was 37±8.0. Female gender, living with family, having good or higher academic achievement, not smoking, supporting anti-tobacco policies, not living with a smoker were associated with higher BATHS-T score. There was no statistically significant difference between the smoking ban at home and in the car and the BATHS-T score. In this respect, the study reached different results from the existing literature. &#x0D; Further studies is needed to elucidate this difference.

Location and home rules of cannabis use – Findings from marijuana use and environmental survey 2020, a nationally representative survey in the United States

Cannabis combustion and aerosolization may be associated with adverse health for users and nonusers through secondhand and thirdhand exposure. As cannabis regulation becomes more lenient, understanding where cannabis is used and whether homes have rules restricting use is needed. This study aimed to identify locations, presence of other people, and in-home rules of cannabis use in the United States (U.S.). This secondary analysis of 3,464 inhalation-based (smoking, vaping, dabbing) cannabis users in past 12 months drew from a cross-sectional probability-based online panel of 21,903 U.S. adults in early 2020, providing nationally representative estimates. We describe presence of other people and location at most recent use (smoking, vaping, dabbing, respectively). We also describe household restrictions on in-home cannabis smoking by cannabis smokers vs non-smokers, and by presence of children in home. Cannabis smoking, vaping, and dabbing most often occurred at users’ own homes (65.7%, 56.8%, and 46.9%, respectively). More than 60% of smoking, vaping, and dabbing occurred with someone else present. About 68% of inhalation-based cannabis users (70% and 55%, smokers and non-smokers, respectively) did not have complete restrictions on in-home cannabis smoking; among them, over a quarter lived with children under 18. In the U.S., inhalation-based cannabis use most commonly occurs at home, with others present and a substantial proportion of users lacking complete in-home cannabis smoking restrictions, raising risks of secondhand and thirdhand smoke exposure. These circumstances demand residential interventions for developing bans on indoor cannabis smoking, especially around vulnerable children.

Thirdhand tobacco smoke exposure increases the genetic background-dependent risk of pan-tumor development in Collaborative Cross mice

Increasing evidence has shown that thirdhand smoke (THS) exposure is likely to induce adverse health effects. An important knowledge gap remains in our understanding of THS exposure related to cancer risk in the human population. Population-based animal models are useful and powerful in investigating the interplay between host genetics and THS exposure on cancer risk. Here, we used the Collaborative Cross (CC) mouse population-based model system, which recapitulates the genetic and phenotypic diversity observed in the human population, to assess cancer risk after a short period of exposure, between 4 and 9 weeks of age. Eight CC strains (CC001, CC019, CC026, CC036, CC037, CC041, CC042 and CC051) were included in our study. We quantified pan-tumor incidence, tumor burden per mouse, organ tumor spectrum and tumor-free survival until 18 months of age. At the population level, we observed a significantly increased pan-tumor incidence and tumor burden per mouse in THS-treated mice as compared to the control (p = 3.04E-06). Lung and liver tissues exhibited the largest risk of undergoing tumorigenesis after THS exposure. Tumor-free survival was significantly reduced in THS-treated mice compared to control (p = 0.044). At the individual strain level, we observed a large variation in tumor incidence across the 8 CC strains. CC036 and CC041 exhibited a significant increase in pan-tumor incidence (p = 0.0084 and p = 0.000066, respectively) after THS exposure compared to control. We conclude that early-life THS exposure increases tumor development in CC mice and that host genetic background plays an important role in individual susceptibility to THS-induced tumorigenesis. Genetic background is an important factor that should be taken into account when determining human cancer risk of THS exposure.

Thirdhand smoke exposure and its toxicological impacts: A review on target organ based studies

Third-hand smoke (THS) is a newly described environmental health hazard that might be defined as a residual cigarette smoke that occurs due to the accumulation of toxins of second-hand smoke (SHS) in the smoking environment. In addition, chemicodynamic of THS may alter due to the interaction with other gases and chemicals present in the environment. THS may cause serious health outcomes in the lungs, liver, skin, heart, and nervous system as well. Hence, it is thought to represent a major health hazard for people, particularly for children, whom exposed to THS where they interact more frequently with these surfaces exposed to THS via hand to mouth transfer. In the present study, it was aimed to summarize the proposed toxicity mechanisms based on in vitro and in vivo studies based on target organ toxicity. In this study, it is aimed to review toxicity mechanisms of THS based on in vitro and in vivo studies on target organ toxicity. Recent studies reported that THS might induce unwanted effects in the respiratory, cardiovascular, nervous, hematopoietic, and skeletal systems and skin. Literature data indicated that THS-mediated oxidative damage and increase in inflammatory response may play an important role in the pathogenesis of cardiovascular and neurobehavioral diseases, especially the target organ lung, and in the future, THS might be defined as a preventable environmental risk factor. Therefore, further studies on THS are needed to define its toxicity mechanism as well as increase the social awareness and legal regulations.

Tobacco Smoke Exposure and Gastrointestinal Problems Among US Children.

This study examined the association between home tobacco smoke exposure (TSE) status and gastrointestinal problems in the past 12 months among US children. We conducted a secondary analysis of the 2018-2019 National Survey of Children's Health cross-sectional data including 20 149 children aged 4 to 10 years. Weighted logistic regression models unadjusted and adjusted for child and family covariates were fitted. Overall, 12.3% of children had home thirdhand smoke (THS) exposure only and 1.8% had home secondhand smoke (SHS) and THS exposure. Unadjusted (odds ratio [OR] = 1.70, 95% confidence interval [CI] = 1.32-2.20) and adjusted (adjusted odds ratio [AOR] = 1.51, 95% CI = 1.14-1.99) logistic regression results indicated that relative to children with no home TSE, children with home THS exposure only were at increased odds of having frequent or chronic difficulty with gastrointestinal problems over the past 12 months. Interventions are critically needed to promote smoking cessation among household members who live with children in order to reduce levels of SHS and THS in their homes.