Passive exposure to tobacco smoke: saliva cotinine concentrations in a representative population sample of non-smoking schoolchildren

Hidradenitis suppurativa in a cohort of overweight and obese children and adolescents

BACKGROUND

Hidradenitis suppurativa (HS) is a chronic, inflammatory, and recurring disease mainly observed in adults. Obesity is considered an important independent factor in HS development and is associated with a higher prevalence of HS in children. We aimed to characterize the clinical presentation of HS in overweight and obese children and adolescents.

METHODS

We performed a cross-sectional observational study during January 2007-April 2015. Overweight and obese patients (5-17 years of age, BMI> 90th percentile) referred to The Children's Obesity Clinic, Department of Paediatrics, Copenhagen University Hospital Holbaek, Denmark, underwent screening for dermatological conditions. A dermatologist ascertained the diagnosis of HS, and disease severity was assessed using Hurley staging and Sartorius score. Tobacco smoke exposure, body mass index (BMI) standard deviation score (SDS), and psychiatric comorbidities were recorded. Our cohort was compared with a reference cohort recruited in a previous study.

RESULTS

A total of 195 children and adolescents underwent screening for dermatological conditions. Nine patients screened positive, and six of these patients were available for examination of whom five presented with HS. All HS cases were mild (median Sartorius score of 9). Four of the five patients (with varying constellations) reported tobacco exposure, a positive family history of HS, and exhibited psychiatric comorbidities.

CONCLUSION

Our findings support that the presence of pediatric HS is correlated with familial disposition to HS and psychiatric comorbidities.

Long-term Results From the FRESH RCT: Sustained Reduction of Children's Tobacco Smoke Exposure

INTRODUCTION

Standard care interventions to reduce children's tobacco smoke exposure (TSE) may not be sufficient to promote behavior change in underserved populations. A previous study demonstrated the short-term efficacy of an experimental counseling intervention, Family Rules for Establishing Smokefree Homes (FRESH) compared with standard care on boosting low-income children's TSE reduction and maternal smoking at 16-week end of treatment (EOT). This study tested long-term posttreatment efficacy of this treatment through a 12-month follow-up.

STUDY DESIGN

This study was a two-arm RCT.

SETTING/PARTICIPANTS

Maternal smokers (n=300) not seeking cessation treatment were recruited from low-income, urban communities. Participants exposed their <4-year-old children to tobacco smoke daily. Data collection and analyses occurred from 2006 to 2018.

INTERVENTION

The FRESH behavioral intervention included 2 home visits and 7 phone sessions. FRESH used cognitive behavioral skills training, support, problem-solving, and positive social reinforcement to facilitate the adoption of increasingly challenging TSE-protection behaviors. No nicotine-replacement therapy or medication was provided.

MAIN OUTCOME MEASURES

Primary outcomes were child cotinine (TSE biomarker) and reported TSE from EOT through 12 months after treatment. A secondary outcome was bioverified maternal smoking cessation.

RESULTS

Compared with controls, children in FRESH had significantly lower cotinine (β= -0.31, p<0.01) and lower maternal-reported TSE (β= -1.48, p=0.001) through the 12-month follow-up. A significant effect of time (β= -0.03, p=0.003) reflected a posttreatment decrease in cotinine. There was no treatment × time interaction, suggesting the treatment effect at EOT was sustained after treatment. Compared with controls, FRESH mothers maintained significantly higher odds of quitting smoking from EOT through 12-month follow-up (OR=8.87, 95% CI=2.33, 33.75).

CONCLUSIONS

Study results with a sample of underserved maternal smokers demonstrated that the short-term effect of FRESH counseling at 16-week EOT was maintained through 12 months after treatment-for both bioverified child TSE reduction and maternal smoking cessation. Smokers in low-income communities demonstrate elevated challenges to success in standard smoking treatment. FRESH follow-up results suggest the high potential value of more-intensive behavioral intervention for vulnerable smokers.

TRIAL REGISTRATION

This study is registered at www.clinicaltrials.gov NCT02117947.

Electronic cigarettes: a task force report from the European Respiratory Society

There is a marked increase in the development and use of electronic nicotine delivery systems or electronic cigarettes (ECIGs). This statement covers electronic cigarettes (ECIGs), defined as "electrical devices that generate an aerosol from a liquid" and thus excludes devices that contain tobacco. Database searches identified published articles that were used to summarise the current knowledge on the epidemiology of ECIG use; their ingredients and accompanied health effects; second-hand exposure; use of ECIGs for smoking cessation; behavioural aspects of ECIGs and social impact; in vitro and animal studies; and user perspectives.ECIG aerosol contains potentially toxic chemicals. As compared to conventional cigarettes, these are fewer and generally in lower concentrations. Second-hand exposures to ECIG chemicals may represent a potential risk, especially to vulnerable populations. There is not enough scientific evidence to support ECIGs as an aid to smoking cessation due to a lack of controlled trials, including those that compare ECIGs with licenced stop-smoking treatments. So far, there are conflicting data that use of ECIGs results in a renormalisation of smoking behaviour or for the gateway hypothesis. Experiments in cell cultures and animal studies show that ECIGs can have multiple negative effects. The long-term effects of ECIG use are unknown, and there is therefore no evidence that ECIGs are safer than tobacco in the long term. Based on current knowledge, negative health effects cannot be ruled out.

Passive exposure to pollutants from conventional cigarettes and new electronic smoking devices (IQOS, e-cigarette) in passenger cars

Smoking in car interiors is of particular concern because concentrations of potentially harmful substances can be expected to be high in such small spaces. To assess the potential exposure for occupants, especially children, we performed a comprehensive evaluation of the pollution in 7 passenger cars while tobacco cigarettes and new electronic smoking products (IQOS, e-cigarette) were being smoked. We collected data on the indoor climate and indoor air pollution with fine and ultrafine particles and volatile organic compounds while the cars were being driven. Smoking of an IQOS had almost no effect on the mean number concentration (NC) of fine particles (>300 nm) or on the PM_2.5 concentration in the interior. In contrast, the NC of particles with a diameter of 25-300 nm markedly increased in all vehicles (1.6-12.3 × 10⁴/cm³). When an e-cigarette was vaped in the interior, 5 of the 7 tested cars showed a strong increase in the PM_2.5 concentration to 75-490 μg/m³. The highest PM_2.5 levels (64-1988 μg/m³) were measured while tobacco cigarettes were being smoked. With the e-cigarette, the concentration of propylene glycol increased in 5 car interiors to 50-762 μg/m³, whereby the German indoor health precaution guide value for propylene glycol was exceeded in 3 vehicles and the health hazard guide value in one. In 4 vehicles, the nicotine concentration also increased to 4-10 μg/m³ while the e-cigarette was being used. The nicotine concentrations associated with the IQOS and e-cigarette were comparable, whereas the highest nicotine levels (8-140 μg/m³) were reached with tobacco cigarettes. Cigarette use also led to pollution of the room air with formaldehyde (18.5-56.5 μg/m³), acetaldehyde (26.5-141.5 μg/m³), and acetone (27.8-75.8 μg/m³). Tobacco cigarettes, e-cigarettes, and the IQOS are all avoidable sources of indoor pollutants. To protect the health of other non-smoking passengers, especially that of sensitive individuals such as children and pregnant women, these products should not be used in cars.

Increasing Home Smoking Restrictions Boosts Underserved Moms' Bioverified Quit Success

Objectives: Standard smoking cessation treatments remain relatively ineffective in vulnerable populations. This study tested whether efforts to restrict residential smoking mediated the counseling treatment - smoking cessation association in a child tobacco smoke exposure (TSE) reduction trial. Methods: Maternal smokers (N = 300) with young children from low-income minority communities were randomized to counseling or standard care control to promote child TSE reduction. Secondary mediation analyses controlled for factors associated with smoking cessation. Results: Counseling group mothers were more likely than controls to increase home smoking restrictions (OR = 1.9, 95% CI 1.1-3.4) and quit smoking (OR = 11.0, 95% CI 6.3-19.2). As hypothesized, increasing home smoking restrictions improved likelihood of bioverified quit status at end of treatment (OR = 2.5, 95% CI 1.1-5.9) and partially mediated the association between counseling intervention and quit status. Conclusions: Results suggest that among maternal smokers known to experience increased challenges to quitting smoking, encouraging efforts to protect children from TSE by increasing home smoking restrictions may be an important counseling intervention element that facilitates smoking cessation.

Passive Smoking, Potential Atopy and Asthma in the First Five Years

Evidence of prolonged exposure to cigarette smoke was sought in a group of 86 children aged five years and under with moderately severe asthma, and in 1199 infants from a mixed background population of Armed Service and civilian families. Asthmatics with a normal serum IgE (less than +1 s.d. for age) made up almost half of the cases and, compared with those with an elevated serum IgE (+1 s.d. for age or more), a greater proportion were male, had experienced prolonged exposure to cigarette smoke, were from Service families and already had fixed chest deformity. It is suggested that, in addition to facilitating the expression of asthma in young potential atopics, passive smoking may be an important contributory cause of the more severe disease reported in the socalled ‘intrinsic’ group. Perhaps the burden of illness and the extent of exposure noted in this survey will prompt renewed efforts to be made to discourage smoking in families, particularly two years before and for at least five years after the birth of a child.

Transgenerational exposure to environmental tobacco smoke

Traditionally, nicotine from second hand smoke (SHS), active or passive, has been considered the most prevalent substance of abuse used during pregnancy in industrialized countries. Exposure to environmental tobacco smoke (ETS) is associated with a variety of health effects, including lung cancer and cardiovascular diseases. Tobacco is also a major burden to people who do not smoke. As developing individuals, newborns and children are particularly vulnerable to the negative effects of SHS. In particular, prenatal ETS has adverse consequences during the entire childhood causing an increased risk of abortion, low birth weight, prematurity and/or nicotine withdrawal syndrome. Over the last years, a decreasing trend in smoking habits during pregnancy has occurred, along with the implementation of laws requiring smoke free public and working places. The decrease in the incidence of prenatal tobacco exposure has usually been assessed using maternal questionnaires. In order to diminish bias in self-reporting, objective biomarkers have been developed to evaluate this exposure. The measurement of nicotine and its main metabolite, cotinine, in non-conventional matrices such as cord blood, breast milk, hair or meconium can be used as a non-invasive measurement of prenatal SMS in newborns. The aim of this review is to highlight the prevalence of ETS (prenatal and postnatal) using biomarkers in non-conventional matrices before and after the implementation of smoke free policies and health effects related to this exposure during foetal and/or postnatal life.

Association of maternal smoking with child cotinine levels

INTRODUCTION

Our aim was to understand the strength of association between parental smoking and child environmental tobacco smoke (ETS) exposure in order to inform the development of future tobacco control policies. ETS was measured using child cotinine levels below the active smoking threshold.

METHODS

Participants were drawn from the Avon Longitudinal Study of Parents and Children and included 3,128 participants at age 7 years and 1,868 participants at age 15 years. The primary outcome was cotinine levels of nonsmoking children, to investigate the relationship between maternal smoking and child cotinine levels. The secondary outcome was cotinine levels of all individuals to investigate the relationship between child smoking and child cotinine levels. Maternal and child smoking behavior was assessed by self-report questionnaire. We adjusted for several sociodemographic variables.

RESULTS

We found an association between maternal smoking and child cotinine at age 7 years (mean cotinine = 1.16ng/ml serum, ratio of geometric means = 3.94, 95% CI = 2.86-5.42) and at age 15 years (mean cotinine = 0.94ng/ml serum, ratio of geometric means = 5.26, 95% CI = 3.06-9.03), after adjustment for potential confounders.

CONCLUSIONS

The magnitude of this association for children whose mothers were heavy smokers was comparable with the quantity of half the levels of cotinine observed among children who were irregular (i.e., nonweekly) active smokers, and it was greater than five times higher than that seen in nonsmoking children whose mothers didn't smoke. This provides further evidence for the importance of public health interventions to reduce smoking exposure in the home.

Secondhand smoke exposure levels in outdoor hospitality venues: a qualitative and quantitative review of the research literature

OBJECTIVE

This paper considers the evidence on whether outdoor secondhand smoke (SHS) is present in hospitality venues at high levels enough to potentially pose health risks, particularly among employees.

DATA SOURCES

Searches in PubMed and Web of Science included combinations of environmental tobacco smoke, secondhand smoke, or passive smoke AND outdoor, yielding 217 and 5,199 results, respectively through June, 2012.

STUDY SELECTION

Sixteen studies were selected that reported measuring any outdoor SHS exposures (particulate matter (PM) or other SHS indicators).

DATA EXTRACTION

The SHS measurement methods were assessed for inclusion of extraneous variables that may affect levels or the corroboration of measurements with known standards.

DATA SYNTHESIS

The magnitude of SHS exposure (PM2.5) depends on the number of smokers present, measurement proximity, outdoor enclosures, and wind. Annual excess PM2.5 exposure of full-time waitstaff at outdoor smoking environments could average 4.0 to 12.2 μg/m3 under variable smoking conditions.

CONCLUSIONS

Although highly transitory, outdoor SHS exposures could occasionally exceed annual ambient air quality exposure guidelines. Personal monitoring studies of waitstaff are warranted to corroborate these modeled estimates.

Assessing secondhand smoke exposure with reported measures

Non-smokers are exposed to tobacco smoke from the burning cigarette and the exhaled smoke from smokers. In spite of decades of development of approaches to assess secondhand smoke exposure (SHSe), there are still unresolved methodological issues. This manuscript summarises the scientific evidence on the use of SHSe reported measures and their methods, objectives, strengths and limitations; and discusses best practices for assessing behaviour leading to SHSe for lifetime and immediate or current SHSe. Recommendations for advancing measurement science of SHSe are provided. Behavioural measures of SHSe commonly rely on self-reports from children and adults. Most commonly, the methodology includes self, proxy and interview-based reporting styles using retrospective recall or diary-style reporting formats. The reporting method used will vary based upon the subject of interest, assessment objectives and cultural context. Appropriately implemented, reported measures of SHSe provide an accurate, timely and cost-effective method for assessing exposure time, location and quantity in a wide variety of populations.

The association between endotoxin and lung function among children and adolescents living in a rural area

BACKGROUND⁄

OBJECTIVES

Knowledge of the effects of domestic endotoxin on children's lung function is limited. The association between domestic endotoxin and asthma or wheeze and lung function among school-age children (six to 18 years of age) was examined. The interaction between endotoxin and other personal and environmental characteristics and lung function was also assessed.

METHODS

A case-control study was conducted in and around the rural community of Humboldt, Saskatchewan, between 2005 and 2007. Parents of cases reported either doctor-diagnosed asthma or wheeze in the previous year. Controls were randomly selected from those not reporting these conditions. Data were collected by questionnaire to ascertain symptoms and conditions, while spirometry was used to measure lung function including forced vital capacity and forced expiratory volume in 1 s. Dust collected from the child's play area floor and the child's mattress was used to quantify endotoxin, and saliva was collected to quantify cotinine levels and assess tobacco smoke exposure.

RESULTS

There were 102 cases and 207 controls included in the present study. Lower forced expiratory volume in 1 s was associated with higher mattress endotoxin load among female cases (beta=-0.25, SE=0.07 [P<0.01]). There was a trend toward lower forced vital capacity, which was associated with higher play area endotoxin load among cases with high tobacco smoke exposure (beta=-0.17, SE=0.09 [P<0.10]).

CONCLUSIONS

Findings indicated that high endotoxin levels present in common household areas of rural children with asthma or wheeze may also affect their lung function. These associations may be potentiated by tobacco smoke exposure and female sex.

Arterial intima-media thickness, endothelial function, and apolipoproteins in adolescents frequently exposed to tobacco smoke

BACKGROUND

Exposure to tobacco smoke is associated with markers of preclinical atherosclerosis in adults, but its effect on arterial structure in adolescents is unknown.

METHODS AND RESULTS

Healthy 13-year-old adolescents from the atherosclerosis prevention trial STRIP were studied. Maximum carotid and aortic intima-media thickness and brachial artery flow-mediated dilation were measured in 494 adolescents using high-resolution ultrasound. Serum lipid, lipoprotein, and apolipoprotein (Apo) A-I and B concentrations were determined using standard methods. Exposure to tobacco smoke was measured annually between ages 8 and 13 years using serum cotinine concentrations, analyzed with gas chromatography. To define longitudinal exposure, cotinine values of children having serum cotinine measured 2 to 6 times during follow-up were averaged and divided into tertiles (exposure groups): low (n=160), intermediate (n=171), and high (n=163). Adolescents with higher longitudinal exposure to tobacco smoke had increased carotid intima-media thickness (exposure groups [mean+/-SD]: low, 0.502+/-0.079 mm; intermediate, 0.525+/-0.070 mm; high, 0.535+/-0.066 mm; P<0.001) and increased aortic intima-media thickness (exposure groups: low, 0.527+/-0.113 mm; intermediate, 0.563+/-0.139 mm; high, 0.567+/-0.126 mm; P=0.008). The flow-mediated dilation decreased when cotinine level increased (exposure groups: low, 10.43+/-4.34%; intermediate, 9.78+/-4.38%; high, 8.82+/-4.14%; P=0.004). Moreover, ApoB (P=0.014) and ApoB/ApoA-I ratio (P=0.045) increased with increase in cotinine level. The associations between tobacco smoke exposure and ultrasound variables were unchanged after adjusting for traditional atherosclerosis risk factors and for ApoB.

CONCLUSIONS

Frequent exposure to tobacco smoke is independently associated with arterial changes of preclinical atherosclerosis and increased ApoB levels among healthy adolescents. Clinical Trial Registration- clinicaltrials.gov. Identifier: NCT00223600.

Trends in and predictors of second-hand smoke exposure indexed by cotinine in children in England from 1996 to 2006

AIMS

To explore trends in and predictors of second-hand smoke (SHS) exposure in children. To identify whether inequalities in SHS exposure are changing over time.

DESIGN

Repeated cross-sectional study with data from eight annual surveys conducted over an 11-year period from 1996 to 2006.

SETTING

England.

PARTICIPANTS

Nationally representative samples of children aged 4-15 years living in private households.

MEASUREMENTS

Saliva cotinine (4-15-year-olds), current smoking status (8-15-year-olds), smoking status of parents and carers, smoking in the home, socio-demographic variables.

FINDINGS

The most important predictors of SHS exposure were modifiable factors-whether people smoke in the house on most days, whether the parents smoke and whether the children are looked after by carers who smoke. Children from more deprived households were more exposed and this remained the case even after parental smoking status has been controlled for. Exposure over time has fallen markedly among children (59% decline over 11 years in geometric mean cotinine), with the most marked decline observed in the period immediately preceding smoke-free legislation. Declines in exposure have generally been greater in children most exposed at the outset. For example, in children whose parents both smoke, median cotinine declined annually by 0.115 ng/ml compared with 0.019 ng/ml where neither parent smokes (P < 0.05).

CONCLUSIONS

In the 11 years leading up to smoke-free legislation in England, the overall level of SHS exposure in children as well as absolute inequalities in exposure have been declining. Further efforts to encourage parents and carers to quit and to avoid smoking in the home would benefit child health.

Assessment of exposure to secondhand smoke at outdoor bars and family restaurants in Athens, Georgia, using salivary cotinine

Exposure to secondhand smoke (SHS) in outdoor settings is a growing public health concern due to recent indoor smoking bans. The objective of this study was to measure salivary cotinine, a metabolite of nicotine, in subjects aged 21-30 exposed to SHS outside bars and restaurants in Athens, Georgia. Nonsmokers participated during 6-hr periods in outdoor standing or seating areas of bars and restaurants where indoor smoking was banned, as well as a control outdoor location with no smokers over six weekends during the summer and early fall of 2007. Pre- and post-exposure saliva samples (N = 25 person-days at the bar site, N = 28 person-days at the restaurant site, and N = 11 person-days at the control) were collected and analyzed for cotinine. The mean change in the response, (ln(post) - ln(pre)) salivary cotinine levels, was significantly impacted by the type of site (bar, restaurant, control) (F = 5.09; d.f. = 2, 6.7; p = 0.0455). The median percent increase in salivary cotinine from pre-test to post-test was estimated to be 162%, 102%, and 16% at the bar, restaurant, and control sites, respectively, values that were significant increases at bars (t = 4.63; d.f. = 9.24; p = 0.0011) and restaurants (t = 4.33; d.f. = 4.47; p = 0.0097) but not at the control sites. On average, these pre-test to post-test increases in salivary cotinine were significantly higher at bar sites than control sites (t = 3.05; d.f. = 9.85; p = 0.0176) and at restaurant sites compared with control sites (t = 2.35; d.f. = 5.09; p = 0.0461). Nonsmokers outside restaurants and bars in Athens, Georgia, have significantly elevated salivary cotinine levels indicative of secondhand smoke exposure.

[Evaluation of new saliva collection device for determination of salivary cotinine, cortisol, dehydroepiandrosterone and testosterone concentrations]

OBJECTIVES

This study was conducted to examine the effectiveness of a new salivary collection device (psi10 mm x 25 mm) made of polypropylene and polyethylene polymers (Salisoft((R))).

METHOD

Experiment 1; We measured the absorption capacity of the new device by two methods. Next, we examined whether the device affected the pH of 0.1 M NaHCO(3) solution (pH 8.7) and 0.1 M sodium phosphate buffer solution (pH 6.0). Experiment 2; We compared three saliva collection methods: by passive drool, using a cotton device (Salivette((R))), and using the new device. Saliva samples were collected from twelve men (average age, 31.5 +/- 17.1 years). Saliva samples were assayed for cotinine, cortisol, dehydroepiandrosterone, and testosterone concentrations by enzyme immunoassay, and the pH of saliva samples were measured.

RESULTS

After this device was put in the mouth for one minute, 1.28 +/- 0.13 mL (mean +/- SD, N = 6) of saliva samples were obtained. The mean pHs of saliva samples collected using Salisoft((R)) and by passive drool did not differ significantly, whereas that of saliva samples collected with Salivette((R)) was significantly low. Saliva samples collected with Salisoft((R)) and those obtained by passive drool did not show significant differences in the concentrations of cotinine, cortisol, dehydroepiandrosterone, and testosterone. Moreover, significant positive correlations were noted between the concentrations in saliva samples collected with Salisoft((R)) and those in saliva samples collected by passive drool.

CONCLUSION

This new device was shown to be suitable for saliva collection for the determination of the concentrations of cotinine and some steroids by enzyme immunoassay.

Effects of postnatal parental smoking on parent and teacher ratings of ADHD and oppositional symptoms

To assess the effects of postnatal parental smoking on subsequent parent and teacher ratings of DSM-IV attention deficit hyperactivity disorder (ADHD) symptoms and oppositional behaviors in children diagnosed with ADHD and their siblings. Children between 5 and 12 years of age with ADHD and their siblings were included. DSM-IV ADHD symptom subscales (Inattentive and hyperactive-impulsive), and oppositionality subscale scores from Conners' Rating Scales were predicted on the basis of parental smoking status in the first 7 years after birth using Generalized Estimating Equations controlling for a range of relevant covariates. Postnatal parental smoking was associated with both parent and teacher ratings of ADHD symptoms and oppositional behavior. After controlling for a number of covariates, several of these relationships were still significant. The risk of maternal smoking for the development of ADHD symptoms does not end during pregnancy. Research on the mechanisms underlying the observed associations is needed.

Assessment of exposure to secondhand smoke by questionnaire and salivary cotinine in the general population of Barcelona, Spain (2004-2005)

OBJECTIVES

To estimate the prevalence of self-reported exposure to secondhand smoke (SHS) in different settings and to describe salivary cotinine concentration and its determinants among non-smokers.

METHODS

Cross-sectional study of a representative sample (N=775) of adult non-smokers in Barcelona, Spain (years 2004-2005). We assessed exposure to SHS using a questionnaire and measurement of salivary cotinine concentration. We calculated prevalence rates of self-reported exposure and medians and geometric means of salivary cotinine concentration. We adjusted for potential confounding factors with multinomial logistic regression models.

RESULTS

The prevalence rate of self-reported exposure to SHS among non-smokers in any setting was 75.7% (95% CI: 72.7%-78.8%). The prevalence of exposure to SHS tended to decrease with age. The geometric mean of cotinine concentrations among non-smokers was 1.49 ng/ml (95% CI: 1.39-1.60 ng/ml) among all subjects, and 1.80 ng/ml (95% CI: 1.37-2.35 ng/ml) in subjects who reported exposure to SHS in all settings. In bivariate and multivariate analyses, the cotinine concentration increased with the number of smokers and the number of cigarettes smoked per day in the presence of non-smokers in the household.

CONCLUSIONS

In this population, self-reported exposure to SHS is very high. Salivary cotinine concentrations in non-smokers are associated with exposure at home.

Etiologic agents and outcome determinants of community-acquired pneumonia in urban children: a hospital-based study

Etiologic clues and prognostic indicators of community-acquired pneumonia (CAP) were sought in a 30-month study of under-5 admissions for acute lower respiratory infections (ALRIs). Investigative tools included blood culture, hemogram, immunofluorescence and serology. Associations of variables were tested using standard statistical tools. Of 419 ALRI, 323 (77%) had pneumonia, 234 (72.4%) bronchopneumonia, 66 (20.4%) lobar pneumonia and 23 (7.1%) both. More than 70% had poor parental socioeconomic parameters, 56.8% were overtly malnourished, 37.8% lived in overcrowded homes and 16.7% had been potentially exposed to wood smoke. Despite preconsultation antimicrobial use in 35.6%, 59 (28.8%) of 205 blood cultures proved positive; Staphylococcus aureus accounted for 22 (37.3%), Klebsiella species nine (15.3%) and Streptococcus pneumoniae three (5.1%). Ninety-two viruses were identified in 61 (50%) of 122 analyses. Respiratory syncytial virus (RSV) accounted for 28 (30.4%), parainfluenza virus type 3 (PIV-3) for 18 (19.5%) and influenza type-A (flu-A) 16 (17.3%). Twenty (16.4%) had > or = 2 viruses, while 40% of bacteremic cases with positive viral identification(s) had PIV-3. Pathogen detection was neither associated with hematologic parameters nor the final respiratory diagnosis. There were 35 (10.8%) deaths. Mortality was associated with maternal illiteracy (p = 0.045), wood smoke exposure (p = 0.006), preconsultation antimicrobial use (p = 0.04), malnutrition (p = 0.0003), bacteremia (p = 0.006) and polymorphonuclear leucocytosis (p = 0.023/0.013). RSV, PIV-3, flu-A, S. aureus and Klebsiella species constitute the major pathogens of pediatric CAP in urban Nigeria, while malnutrition, wood smoke exposure and bacteremia are strong risk factors of mortality. The poor prognostic import of antimicrobial abuse, vis-a-vis the apparent selection of necrotizing pathogens, are compelling indications for a reappraisal of current regional antimicrobial policies and exploring newer frontiers of disease control, including vaccine prevention.

Changes in child exposure to environmental tobacco smoke (CHETS) study after implementation of smoke-free legislation in Scotland: national cross sectional survey

OBJECTIVE

To detect any change in exposure to secondhand smoke among primary schoolchildren after implementation of smoke-free legislation in Scotland in March 2006.

DESIGN

Comparison of nationally representative, cross sectional, class based surveys carried out in the same schools before and after legislation.

SETTING

Scotland.

PARTICIPANTS

2559 primary schoolchildren (primary 7; mean age 11.4 years) surveyed in January 2006 (before smoke-free legislation) and 2424 in January 2007 (after legislation).

OUTCOME MEASURES

Salivary cotinine concentrations, reports of parental smoking, and exposure to tobacco smoke in public and private places before and after legislation.

RESULTS

The geometric mean salivary cotinine concentration in non-smoking children fell from 0.36 (95% confidence interval 0.32 to 0.40) ng/ml to 0.22 (0.19 to 0.25) ng/ml after the introduction of smoke-free legislation in Scotland-a 39% reduction. The extent of the fall in cotinine concentration varied according to the number of parent figures in the home who smoked but was statistically significant only among pupils living in households in which neither parent figure smoked (51% fall, from 0.14 (0.13 to 0.16) ng/ml to 0.07 (0.06 to 0.08) ng/ml) and among pupils living in households in which only the father figure smoked (44% fall, from 0.57 (0.47 to 0.70) ng/ml to 0.32 (0.25 to 0.42) ng/ml). Little change occurred in reported exposure to secondhand smoke in pupils' own homes or in cars, but a small decrease in exposure in other people's homes was reported. Pupils reported lower exposure in cafes and restaurants and in public transport after legislation.

CONCLUSIONS

The Scottish smoke-free legislation has reduced exposure to secondhand smoke among young people in Scotland, particularly among groups with lower exposure in the home. We found no evidence of increased secondhand smoke exposure in young people associated with displacement of parental smoking into the home. The Scottish smoke-free legislation has thus had a positive short term impact on young people's health, but further efforts are needed to promote both smoke-free homes and smoking cessation.

Impact of repeated lifestyle counselling in an atherosclerosis prevention trial on parental smoking and children's exposure to tobacco smoke

AIM

To determine whether repeated infancy-onset lifestyle counselling alters parental smoking and children's exposure to tobacco smoke.

METHODS

In 1990, 1062 healthy infants were recruited to a randomized, ongoing atherosclerosis prevention trial (STRIP). Intervention families received at least twice a year individualized nutrition and lifestyle counselling. By 1999, 652 8-y-old children continued participation. Exposure to tobacco smoke was evaluated using serum cotinine concentration. Parents' smoking was also assessed using questionnaires and interviews.

RESULTS

Parents' smoking decreased during the study similarly in the intervention and control groups. Of the 8-y-old children, 46% had detectable serum cotinine concentration, suggesting exposure to tobacco smoke during the past few days. All children were non-smokers. Serum cotinine concentrations did not differ between the intervention and control children. Children's cotinine values were highest in the families where either father or both parents were smokers.

CONCLUSION

Participation in the atherosclerosis prevention trial slightly decreased smoking among the intervention and control parents. However, counselling led to no differences in parental smoking between the two groups, or in exposure of the intervention and control children to tobacco smoke. This study suggests that more detailed and targeted intervention is required to achieve a significant effect on children's tobacco smoke exposure.

Les marqueurs d’exposition au tabagisme passif

INTRODUCTION

Tobacco smoke is one of the most common air pollutants found in the indoor environment. Passive smoking is defined as the involuntary inhalation of tobacco smoke present in the air. This article examines the advantages and limitations of the methods that are available to measure environmental tobacco smoke exposure.

STATE OF THE ART

Passive smoking can be assessed either by measuring tobacco smoke pollutants found in the air directly or by using biomarker assays, an indirect measure of exposure.

CONCLUSION

As far as the direct measurement of air pollutants is concerned, nicotine and 3-Ethenylpyridine levels seem most suitable because of their specificity. Four specific biological markers of tobacco smoke exposure are available: nicotine, cotinine, thiocyanates, and protein or DNA adducts. Only urinary cotinine assay can be retained as a reliable marker of exposure to tobacco smoke. It has been used as a reference in most epidemiological studies but only reflects tobacco exposure over the preceding 48 hours. The measurement of nicotine and cotinine levels in the appendages of the skin (hair and nails) reflects exposure to tobacco over the previous three months and could become a better reference marker in epidemiological and toxicological studies.

Measuring tobacco smoke exposure: quantifying nicotine/cotinine concentration in biological samples by colorimetry, chromatography and immunoassay methods

Procedures to assess tobacco smoke exposure are reviewed and biomarkers used for determining the smoking status of an individual are compared. Methods used to extract these biomarkers from saliva, urine, and blood and the advantages and disadvantages of the assays are discussed. Finally, the procedures used to measure the levels of cortisol, a stress hormone speculated to be linked to nicotine metabolism, are discussed.

Determinants of children's exposure to environmental tobacco smoke (ETS): a study in Southern Germany

Maternal smoking has been repeatedly found to be the most important determinant of children's exposure to environmental tobacco smoke (ETS). Here, we further investigated predictors for the urinary cotinine/creatinine ratio (CCR, ng/mg) in 1220 preschool children for the year 1996. Children from smoking homes (35.1%) had significantly higher CCR than children from nonsmoking homes (mean: 55.5 vs. 14.9 ng/mg). The level of education of the parents was a strong predictor for CCRs even after adjusting for number of cigarettes smoked, maternal smoking and dwelling space. Additionally, dwelling space was inversely related to children's urinary cotinine level. The CCR- levels in children investigated in 1996 and 1998 were significantly correlated (Pearson's r=0.67). The parents of 806 children agreed for a visit to their homes. In 79 of the 536 (14.7%) of the self-reported, nonsmoking households, smoking was admitted during the visit. The mean urinary CCR of these children was 25.2 ng/mg. We conclude that in addition to parental smoking behaviour, other variables such as dwelling space and social and educational status predict the children's exposure to ETS. Our data also revealed that a considerable percentage of parents denied the ETS exposure of their children at home.

Asthma management and environmental tobacco smoke exposure reduction in Latino children: a controlled trial

OBJECTIVES

This study tested the efficacy of coaching to reduce environmental tobacco smoke (ETS) exposure among asthmatic Latino children.

DESIGN

After asthma management education, families were randomly assigned to no additional service (control condition) or to coaching for ETS exposure reduction (experimental condition).

SETTING

The study was conducted in San Diego, California.

PARTICIPANTS

Two hundred four Latino children (ages 3-17 years) with asthma participated.

INTERVENTION

Approximately 1.5 hours of asthma management education was provided; experimental families also obtained 7 coaching sessions ( approximately 45 minutes each) to reduce ETS exposure.

OUTCOME MEASURES

Reported ETS exposure and children's urine cotinine were measured.

RESULTS

Parents in the coached condition reported their children exposed to significantly fewer cigarettes than parents of control children by 4 months (postcoaching). Reported prevalence of exposed children decreased to 52% for the coached families, but only to 69% for controls. By month 4, mean cotinine levels decreased among coached and increased among control children. Cotinine prevalence decreased from 54% to 40% among coached families, while it increased from 43% to 49% among controls. However, cotinine levels decreased among controls to the same level achieved by coached families by the 13-month follow-up.

CONCLUSIONS

Asthma management education plus coaching can reduce ETS exposure more than expected from education alone, and decreases in the coached condition may be sustained for about a year. The delayed decrease in cotinine among controls is discussed.

Determination of urinary and salivary cotinine using gas and liquid chromatography and enzyme-linked immunosorbent assay

The objective of this study was to compare cotinine concentrations in urine and saliva using gas chromatography (GC), high-performance liquid chromatography (HPLC) and enzyme-linked immunosorbent assay (ELISA). Ninety-four subjects were selected (27 smokers and 67 non-smokers) and interviewed using questionnaire. Of the non-smokers, 39 had been exposed to environmental tobacco smoke (ETS) and 28 had not been exposed to ETS. Cotinine levels among smokers were highest using all three measurements, followed by ETS exposed subjects and non-smokers. Cotinine levels in urine, using HPLC, correlated significantly with levels measured using ELISA (r=0.92) and GC-nitrogen-phosphorus detection (NPD) (r=0.92). Salivary cotinine levels measured using ELISA did not correlate significantly with either HPLC (r=0.37) or GC-NPD (r=0.33) measurements. Multiple regression models were used to adjust for age, gender, drug use and health status, and it was found that cotinine levels in urine and saliva were significantly correlated with smoking pack-year. The authors conclude that urinary cotinine concentration is a more accurate biomarker for ETS than salivary cotinine concentration.

Is the hair nicotine level a more accurate biomarker of environmental tobacco smoke exposure than urine cotinine?

STUDY OBJECTIVE

The aim of this study was to compare the two biomarkers of exposure to environmental tobacco smoke (ETS); urine cotinine and hair nicotine, using questionnaires as the standard.

DESIGN

A cross sectional study of children consecutively admitted to hospital for lower respiratory illnesses during the period of the study.

SETTINGS

Three regional hospitals in the larger Wellington area, New Zealand.

PARTICIPANTS

Children aged 3-27 months and admitted to the above hospitals during August 1997 to October 1998. A total of 322 children provided 297 hair samples and 158 urine samples.

MAIN RESULTS

Hair nicotine levels were better able to discriminate the groups of children according to their household's smoking habits at home (no smokers, smoke only outside the home, smoke inside the house) than urine cotinine (Kruskall-Wallis; chi(2)=142.14, and chi(2)=49.5, respectively (p<0.0001)). Furthermore, hair nicotine levels were more strongly correlated with number of smokers in the house, and the number of cigarettes smoked by parents and other members of the child's households. Hair nicotine was better related to the questionnaire variables of smoking in a multivariate regression model (r(2)=0.55) than urine cotinine (r(2)=0.31).

CONCLUSIONS

In this group of young children, hair nicotine was a more precise biomarker of exposure to ETS than urine cotinine levels, using questionnaire reports as the reference. Both biomarkers indicate that smoking outside the house limits ETS exposure of children but does not eliminate it.

Validation of smoking status in clinical research into inflammatory periodontal disease

BACKGROUND

Tobacco smoking is an accepted risk factor for periodontal disease. Most studies in the periodontal literature rely on reported smoking habits which can be unreliable. This review specifically addresses this problem.

METHODS

Methods of assessing tobacco smoke exposure, variation in individual smoking habits, classification of former/ex-smokers, and validation of abstinence in smoking cessation studies receive attention.

DISCUSSION

Additionally, clinical studies that have examined periodontal health in subjects with validated smoking status are discussed.

Passive smoking in children: effect of avoidance strategies, at home as measured by hair nicotine levels

Hair nicotine levels were studied among children, relative to their caregivers' reported exposure to environmental tobacco smoke. A total of 117 children, aged 3 months to 10 years, were recruited consecutively from hospital inpatients, and their respective parents or caregivers were interviewed. Degree of exposure to environmental tobacco smoke was assessed via questionnaire. Scalp hair samples were collected from children and were assayed for nicotine. Levels of nicotine in hair among children reportedly exposed to smokers were higher than levels among unexposed children (chi2 = 26.46, p < .0001). In addition, hair nicotine levels were higher among children with mothers who smoked, compared with those whose mothers did not smoke. Whether household members smoked outside or inside the house had no significant effect on hair nicotine levels of children. Hair nicotine levels differed between children who were reportedly unexposed to environmental tobacco smoke at home and those who were exposed. Smoking outside the home, as reported by parents, did not cause a reduction in nicotine levels in the hair of children.

Antioxidants and protein carbonyls in bronchoalveolar lavage fluid of children: normal data

Antioxidant-oxidant imbalances in bronchoalveolar lavage fluid (BAL) are thought to contribute to oxidative stress in respiratory disease. However, normal reference ranges for BAL antioxidants and oxidized proteins in children are not available. In this study, we recruited 124 children attending for elective surgery for a noninflammatory condition; 83 were nonasthmatic, nonatopic (N) and 41 were nonasthmatic, atopic (NA). A nonbronchoscopic lavage was performed and ascorbate, uric acid, alpha-tocopherol, and protein carbonyl (as a measure of oxidative damage) concentrations were determined in BAL fluid. The 95% reference range was 0.112-1.897 micromol/L for ascorbate, 0.149-2.163 micromol/L for urate, 0.0029-0.066 micromol/L for alpha-tocopherol, and 0.280-4.529 nmol/mg for protein carbonyls in BAL fluid. Age, gender, and exposure to environmental tobacco smoke did not affect the concentration of ascorbate, urate, alpha-tocopherol, or protein carbonyls. However, in multiple linear regression analyses, the type of home heating (glass-fronted fires or oil-fired central heating) was found to influence ascorbate and urate concentrations in the BAL fluid (ss-coefficient for ascorbate: 0.445, p = 0.031; for urate: 0.114, p = 0.001). There was no significant difference between the N and NA group in BAL fluid concentrations of ascorbate, urate, or protein carbonyls. The alpha-tocopherol concentration was significantly increased in the NA group (p = 0.037). Uric acid and alpha-tocopherol concentrations in BAL fluid and serum were not correlated. Intriguingly, serum and BAL ascorbate concentrations were significantly correlated (r = 0.297, p = 0.018, n = 63), which may offer an explanation for why supplementing the diet with vitamin C can improve asthma symptoms. Further studies will investigate the role of BAL antioxidant concentrations in children with inflammatory respiratory diseases.

Evaluation of the effect of passive smoking on otitis media in children by an objective method: urinary cotinine analysis

OBJECTIVES

We aimed to determine objectively the effect of the passive smoking on otitis media with effusion (OME) and recurrent otitis media (ROM) by using the method of cotinine urinalysis.

STUDY DESIGN

We designed a prospective case-control study with follow-up of the case group for 1 year after insertion of tympanostomy tubes to evaluate postoperative complications such as otorrhea and early extrusion (<6 months), in case a significant risk factor was found.

METHODS

One hundred fourteen children between 3 and 8 years of age requiring tympanostomy tubes because of OME and ROM were chosen and compared with 40 age-matched children. Exposure to environmental tobacco smoke was assessed by cotinine urinalysis, which was performed by means of the radioimmunoassay method.

RESULTS

In this study, 73.7% (84 of 114) of the children in the case group and 55.0% (22 of 40) of the children in the control group were found to be "exposed" (P = .0461). This difference was statistically significant. Comparing the cotinine urinalysis results with parental smoking histories, 23.1% (9 of 39) of the children without parental smoking histories were "exposed" to tobacco smoke versus 84.3% (97 of 115) of the children with parental smoking histories (at least one person smoking).

CONCLUSIONS

Our results indicate that sidestream smoking increases the risk of OME and ROM. Legal regulations and guidelines must be established to protect children from passive smoking. Because cotinine urinalysis is a noninvasive and reliable method for the determination of passive smoking, it can be used for that purpose.

Assessment of environmental tobacco smoke exposure in children with asthmatic symptoms by questionnaire and cotinine concentrations in plasma, saliva, and urine

To validate a detailed questionnaire for assessment of environmental tobacco smoke (ETS) exposure by the biomarker cotinine in various media, a population-based study in the urban area of Malmö, Sweden was performed in children aged 8-13 years with and without asthmatic symptoms. There were strong correlations between urinary and saliva cotinine concentrations and also, though to a lesser extent, between these media and plasma. Even a detailed questionnaire gave only a rough picture of the ETS exposure, as indicated by the biomarkers. In a multivariate model, the most significant questionnaire-derived predictor of the cotinine levels was the maternal smoking habits; other questionnaire variables gave only a minimal explained variance. Children with a history of asthmatic symptoms had statistically significantly lower median cotinine levels in urine and saliva compared to referent children, most likely because of the antismoking information to their parents. This should be considered in epidemiological studies of ETS risks.

Testing for drugs of abuse in saliva and sweat

The detection of marijuana, cocaine, opiates, amphetamines, benzodiazepines, barbiturates, PCP, alcohol and nicotine in saliva and sweat is reviewed, with emphasis on forensic applications. The short window of detection and lower levels of drugs present compared to levels found in urine limits the applications of sweat and saliva screening for drug use determination. However, these matrices may be applicable for use in driving while intoxicated and surveying populations for illicit drug use. Although not an illicit drug, the detection of ethanol is reviewed because of its importance in driving under the influence. Only with alcohol may saliva be used to estimate blood levels and the degree of impairment because of the problems with oral contamination and drug concentrations varying depending upon how the saliva is obtained. The detection of nicotine and cotinine (from smoking tobacco) is also covered because of its use in life insurance screening and surveying for passive exposure.

Objective measurements of nicotine exposure in victims of sudden infant death syndrome and in other unexpected child deaths

OBJECTIVE

Self-reported maternal smoking is associated with a dose-related-increase in the risk of sudden infant death syndrome (SIDS). The aim of this study was to measure objectively whether victims of SIDS are more exposed to tobacco smoke before death than infants who die unexpectedly of other causes.

DESIGN

Continine levels in pericardial fluid were used as an indicator of exposure. Levels > 5 ng/mL indicated significant exposure, and levels > 20 ng/mL indicated heavy exposure. Samples were obtained from all sudden deaths in children < 7 years of age that occurred from 1990 through 1993 in southeastern Norway. Twenty four infants died of SIDS, 12 infants of infections, and 9 of accidents (median age 4.5, 5, and 35 months, respectively).

RESULTS

Compared with the age-matched infectious deaths, a significantly higher proportion of victims of SIDS had been significantly (92% vs 67%) or heavily exposed (25% vs 0%) to nicotine, (P < .05). Median cotinine levels in infants with SIDS, 15.8 ng/mL, were significantly higher than in infants who had infectious deaths 7.1 ng/mL (P < .003) but were comparable to those of accident victims (12.9 ng/mL, not significant).

CONCLUSIONS

Victims of SIDS are more often and more heavily exposed to tobacco smoke doses before death than are infants who have sudden infectious deaths. Accidental death in infancy and childhood is often associated with a significant exposure to nicotine.

What determines levels of passive smoking in children with asthma?

BACKGROUND

Children with parents who smoke are often exposed to high levels of environmental tobacco smoke, and children with asthma are particularly susceptible to the detrimental effects of passive smoking. Data were collected from parents who smoke and from their asthmatic children. The families are currently taking part in a randomised controlled trial to test an intervention designed to reduce passive smoking in children with asthma. This paper reports on the baseline data. Questionnaire data and cotinine levels were compared in an attempt to assess exposure and to identify factors which influence exposure of the children. The aim of the study was to identify the scope for a reduction in passive smoking by these children.

METHODS

A sample of 501 families with an asthmatic child aged 2-12 years was obtained. Factors influencing passive smoking were assessed by interviewing parents. Cotinine levels were measured from saliva samples using gas liquid chromatography with nitrogen phosphorous detection.

RESULTS

Cotinine levels in children were strongly associated with the age of the child, the number of parents who smoked, contact with other smokers, the frequency of smoking in the same room as the child, and crowding within the home. Parental cotinine levels, the amount smoked in the home, and whether the home had a garden also exerted an independent effect on cotinine levels in the children.

CONCLUSIONS

Many children are exposed to high levels of environmental tobacco smoke and their cotinine levels are heavily dependent upon proximity to the parent who smokes. Parents who smoke have a unique opportunity to benefit their child's health by modifying their smoking habits within the home.

The internal dose of passive smoking at home depends on the size of the dwelling

As part of a longitudinal study two urine samples (survey 1 in 1991 and survey 2 in 1992) were collected from 602 elementary school children to investigate the relationship between urinary cotinine excretion (UCE) and the daily consumption of cigarettes at home (exposure). Size of the dwelling, educational level, and maternal smoking were taken into consideration as additional predictors. The history regarding parental smoking habits and confounding variables was ascertained by standardized questionnaires completed by the parents. Cotinine was measured using gas chromatography selected ion monitoring. UCE was expressed as cotinine/creatinine (ng/mg). In children with detectable UCE in survey 1 (35%) and in survey 2 (44%) the excretion ranged between 1.5 and 24.7 ng/mg (5-95%) and between 1.2 and 25.2 ng/mg, respectively. UCE measurements in both surveys were highly correlated (r = 0.65, P = 0.0001), and 59.6% of the UCE in survey 2 can be explained in linear regression by the UCE in survey 1. Using multiple linear regression, the categorized number of cigarettes reported to be consumed at home (20 cigarettes and more: 1991, P = 0.0001; 1992, P = 0.0003) and low educational level of the parents (P = 0.011 in 1991, P = 0.04 in 1992) were positively associated with UCE, whereas the size of the dwelling turned out to be negatively associated with UCE (P = 0.12 in 1991, P = 0.001 in 1992). In small dwellings (< or = 80 m2) the effect of exposure on UCE was much more pronounced. In conclusion, a single UCE measurement provides information which is widely stable within a yearly interval and is related to passive smoke history as well as to socio-economic status and the size of the dwelling. The latter variable should be considered as an effect modifier of exposure on internal dose and should be taken into account in future studies on passive smoke exposure.

Involuntary exposure to tobacco smoke in adolescents: urinary cotinine and environmental factors

The relationship between environmental tobacco smoke exposure and urinary cotinine was studied in 434 14-y-old schoolchildren. To estimate the independent contribution of physiological and environmental variables to cotinine concentrations, we conducted a multiple regression analysis of log-transformed cotinine (R(2) = .21, p < .0001). Environmental tobacco smoke exposure was associated with sharing a household with members who smoked. The most profound associations were linked to (a) the smoking habits of the mother (beta = 5.135, p = .0397); (b) the combined smoking habits of the mother and other family members (beta = 8.201, p = .0020); and (c) the total number cigarettes smoked each day by family members in the household (beta = 0.217, p = .0008). Passive smoke exposure of adolescents is a preventable risk that could be reduced by improving ventilation and by increasing the living space available to each family member. Parents should avoid smoking at home in the presence of their children.

Passive smoking in children. Racial differences in systemic exposure to cotinine by hair and urine analysis

Passive smoking has been shown to adversely affect the health of infants and children. Black children and adults appear to be more susceptible to a variety of tobacco smoke health hazards for unknown reason. The objectives of this study were as follows: (1) to correlate the number of cigarettes reported to have been smoked by parents with urine and hair concentrations of cotinine in children; and (2) to identify race differences in systemic exposure to cotinine in children. This was an observational study in a consulting pediatric office on 169 nonsmoking children between 2 and 18 years of age, not actively smoking. The outcome measures of interest were urinary cotinine concentrations corrected for milligram of creatinine and hair concentration of cotinine (per milligram of hair). There were significant correlations between the number of cigarettes the child was exposed to and urinary cotinine (r = 0.68, p = 0.0001) or hair cotinine concentrations (r = 0.19, p = 0.02), and between urinary and hair cotinine (r = 0.3, p = 0.0005). In this cohort, parents of black children (n = 21) tended to smoke less (6.6 +/- 3/d, mean +/- SEM) than white parents (n = 97) (12 +/- 1.8, mean +/- SEM) (p = 0.2). Despite being exposed to less cigarettes, black children had higher hair concentrations of cotinine than white children (0.89 +/- 0.25 ng/mg vs 0.48 +/- 0.05 ng/mg; p = 0.05). The ratio hair/urine concentrations of cotinine was twofold higher in black children (0.035 +/- 0.01 vs 0.019 +/- 0.002; p = 0.004). White children with dark hair did not differ significantly from white children with fair hair in any of these indexes. The amount of urinary cotinine per milligram of creatinine caused by 1 cigarette per day was twofold higher in black children (14.7 +/- 5.2 ng/mg of creatinine) than in white children (6.3 +/- 1.2 ng/mg of creatinine) (p = 0.02). These data suggest that black children handle cigarette smoke differently from white children and that black children have higher systemic exposure to this constituent of cigarette smoke.

Questionnaire data as predictors of urinary cotinine levels among nonsmoking adolescents

The strength of association between urinary cotinine and questionnaire data on passive smoking among 542 adolescents was evaluated. There were 103 individuals with urinary cotinine higher than 30 ng/ml; they were compared with all other subjects. The single variable that best predicted the urinary cotinine level was maternal smoking. A strong effect was made by house size and, consequently, house crowding. Maternal smoking and house crowding had a synergic effect. The subject's perception of passive smoking at home also was an independent indication of a high cotinine level. The final model had a fairly good sensitivity, whereas the specificity was somewhat lower. The results suggest that maternal smoking, house crowding, and subject's perception of a smoky environment could be surrogate indices of high passive smoking exposure in this age group and could be useful for epidemiologic studies.

Chemical analyses as validators in smoking cessation programs

This review addresses the use of chemical analyses to validate the smoking status of a participant in a smoking cessation program. Pharmacokinetic and chemical validation literature leads to the conclusion that chemical analyses are most reliably used to confirm abstinence from smoking rather than as quantitative measures of nicotine intake or smoking activity. Analytical methodologies used in smoking validation studies are reviewed with their advantages and disadvantages. Close collaboration of behavioral scientists and analytical chemists is encouraged to validate the smoking status of participants in a smoking cessation program.

Passive smoking effects on wheezy bronchitis

Previous epidemiological studies have associated parental smoking with an increased incidence of lower respiratory illness and bronchial asthma. The aim of the present study was to investigate the association between parental smoking habits and diagnosed wheezy bronchitis in schoolchildren in Saudi Arabia. In a cross-sectional study 3,041 schoolchildren ages seven to 12 years were randomly selected in Dammam, Jeddah, and Riyadh; representing three different geoclimatic regions of Saudi Arabia. Standardized questionnaires were used in our study. The results showed that paternal smoking had a significant effect on the frequency of wheezing when paternal and maternal smoking were considered separately. There was no considerable variation in the parental smoking habits in three areas. The association between passive smoking and diagnosed wheezy bronchitis and frequency of wheezing attacks was highly significant (P<0.0001). Overall, the results tend to confirm that there is a real effect of passive smoking on the respiratory health of children and that paternal smoking is a risk factor for wheezy bronchitis in children.

Determinants of passive smoking in children in Edinburgh, Scotland

OBJECTIVES

Using saliva cotinine as a quantitative marker, we examined the contribution of factors other than parental smoking to children's passive exposure to tobacco smoke.

METHODS

Saliva specimens from a random sample of 734 7-year-old schoolchildren in Edinburgh, Scotland, were analyzed for cotinine. Their parents completed a questionnaire covering smoking habits and conditions in the home.

RESULTS

A number of independent predictors of cotinine were identified in addition to the main one of smoking by household members. These predictors included home ownership, social class, day of the week, season of the year, number of parents present, crowding in the home, the number of children in the household, and sex. Cotinine was higher in children from less advantaged backgrounds, during winter, on Mondays, in girls, and when fewer other children were present. The effects were similar between children from nonsmoking and smoking homes.

CONCLUSIONS

Questionnaire measures of parental smoking are insufficient to fully characterize young children's exposure to passive smoking. Because socioeconomic variables contribute to measured exposure, passive-smoking studies that treat class as a confounder and control for it may be overcontrolling.