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Background: Both temperature and humidity may independently or jointly contribute to the risk of influenza infections. We examined the relations between the level and decrease of temperature, humidity and the risk of influenza A and B virus infections in a subarctic climate., Methods: We conducted a case-crossover study among military conscripts (n = 892) seeking medical attention due to respiratory symptoms during their military training period and identified 66 influenza A and B cases by PCR or serology. Meteorological data such as measures of average and decline in ambient temperature and absolute humidity (AH) during the three preceding days of the onset (hazard period) and two reference periods, prior and after the onset were obtained., Results: The average temperature preceding the influenza onset was -6.8 ± 5.6°C and AH 3.1 ± 1.3 g/m3. A decrease in both temperature and AH during the hazard period increased the occurrence of influenza so that a 1°C decrease in temperature and 0.5 g decrease per m3 in AH increased the estimated risk by 11% [OR 1.11 (1.03 to 1.20)] and 58% [OR 1.58 (1.28 to 1.96)], respectively. The occurrence of influenza infections was positively associated with both the average temperature [OR 1.10 per 1°C (95% confidence interval 1.02 to 1.19)] and AH [OR 1.25 per g/m3 (1.05 to 1.49)] during the hazard period prior to onset., Conclusion: Our results demonstrate that a decrease rather than low temperature and humidity per se during the preceding three days increase the risk of influenza episodes in a cold climate.

Background: Street vending, a dominant occupation in urban areas of developing countries exposes the vendors to several environmental pollutants. We investigated whether work as street vendor impairs foetal growth and shortens gestational duration, and evaluated to what extent exposure to traffic-related air pollution is responsible for these adverse effects., Methods: A cross-sectional study was conducted among mothers and their newborns accessing postnatal services at the Korle Bu Teaching Hospital in Accra, Ghana in 2010, focusing on 105 street vendors and a reference group of 281 mothers. We categorized exposure to traffic-related air pollution on the basis of street vending activity patterns and traffic density in the working area., Results: Multivariate linear regression analysis adjusting for age, social class, marital status and gravidity of mothers, sex of neonate, and indoor air pollution, indicated a 177 g (95% CI: 324, 31) reduction in birth weight among street vendors. Sensitivity analysis performed by restricting the analysis to term births showed further reductions in birth weight. Generalized linear models adjusting for confounders indicated a 35% (risk ratio (RR)=1.35; 95% CI: 0.87, 2.12) increased risk of LBW, albeit statistically not significant. LBW risk increased in the sensitivity analysis but was also not statistically significant. The risk of PTB was not associated with street vending (RR=1.03; 95% CI: 0.67, 1.58). The exposure-response relations observed were not consistent. Moderate activity patterns and high traffic density jointly was associated with a statistically significant 84% (RR=1.84; 95% CI: 1.05, 3.24) increased risk of LBW., Conclusion: Street vending during pregnancy is a determinant of average foetal growth and risk of LBW. More research is required to further quantify their effects on pregnancy outcomes and safeguard maternal and perinatal health in developing countries., (Copyright © 2013 Elsevier GmbH. All rights reserved.)

Background: The occurrence of cold temperature-related symptoms has not been investigated previously in young adults, although cold weather may provoke severe symptoms leading to activity limitations, and those with pre-existing respiratory conditions may form a susceptible group. We tested the hypothesis that young adults with asthma and allergic rhinitis experience cold-related respiratory symptoms more commonly than young adults in general., Methods: A population-based study of 1623 subjects 20-27 years old was conducted with a questionnaire inquiring about cold weather-related respiratory symptoms, doctor-diagnosed asthma and rhinitis, and lifestyle and environmental exposures., Results: Current asthma increased the risk of all cold weather-related symptoms (shortness of breath adjusted PR 4.53, 95% confidence interval 2.93-6.99, wheezing 10.70, 5.38-21.29, phlegm production 2.51, 1.37-4.62, cough 3.41, 1.97-5.87 and chest pain 2.53, 0.82-7.79). Allergic rhinitis had additional effect especially on shortness of breath (7.16, 5.30-9.67) and wheezing (13.05, 7.75-22.00), some on phlegm production (3.69, 2.49-5.47), but marginal effect on cough and chest pain., Interpretation: Our study shows that already in young adulthood those with asthma, and especially those with coexisting allergic rhinitis, experience substantially more cold temperature-related respiratory symptoms than healthy young adults. Hence, young adults with a respiratory disease form a susceptible group that needs special care and guidance for coping with cold weather., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Background: A substantial proportion of the world's population is exposed to indoor dampness-related exposures. Since the 1990s, studies have assessed the relation between indoor dampness and mold and rhinitis, but the evidence has been inconclusive. No previous meta-analysis has been reported on this topic., Objective: We conducted a systematic review and meta-analysis of studies on the relations between indoor dampness and mold and the risk of different types of rhinitis and investigated whether these relations differ according to the type of exposure., Methods: A systematic search of the Ovid MEDLINE and EMBASE databases was conducted (1950 through August 2012), and reference lists of relevant articles were reviewed. Cross-sectional, case-control, and cohort studies in children or adults were selected according to a priori criteria and evaluated by 3 authors independently., Results: Thirty-one studies on rhinitis, allergic rhinitis (AR), or rhinoconjunctivitis were included. In meta-analyses the largest risk was observed in relation to mold odor (rhinitis: 2.18 [95% CI, 1.76-2.71]; AR: 1.87 [95% CI, 0.95-3.68]). The risk related to visible mold was also consistently increased (rhinitis: 1.82 [95% CI, 1.56-2.12]; AR: 1.51 [95% CI, 1.39-1.64]; rhinoconjunctivitis: 1.66 [95% CI, 1.27-2.18]). In addition, exposure to dampness was related to increased risk of all types of rhinitis., Conclusion: This meta-analysis provides new evidence that dampness and molds at home are determinants of rhinitis and its subcategories. The associations were strongest with mold odor, suggesting the importance of microbial causal agents. Our results provide evidence that justifies prevention and remediation of indoor dampness and mold problems, and such actions are likely to reduce rhinitis., (Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.)

Rationale: Identification of the subpopulation especially susceptible to the adverse effects of second-hand smoke exposure (SHS) would be useful for preventive actions and interventions., Objectives: To investigate whether asthmatic heredity indicates susceptibility to the effects of SHS on the risk of adult-onset asthma., Methods: A population-based incident case-control study of clinically defined adult-onset asthma and randomly drawn control subjects (adults 21-63 yr old) from a geographically defined area in South Finland. After excluding current and ex-smokers there were 226 cases and 450 disease-free control subjects., Measurements and Main Results: Our outcome measure was new adult-onset asthma. Parental asthma and recent SHS had a synergistic effect on the risk of asthma, the adjusted odds ratio being 1.97 (95% confidence interval, 1.12-3.45) for SHS; 2.64 (1.65-4.24) for parental asthma; and 12.69 (3.44-46.91) for their joint effect (relative excess risk due interaction, 9.08 [-0.22 to 43.18]). Synergistic effect followed a dose-dependent pattern with both recent and cumulative SHS exposures, with relative excess risk due interaction for parental asthma and over 100 SHS cigarette-years of 6.17 (0.57-19.16)., Conclusions: This is the first study showing that individuals with asthmatic heredity have a considerably increased risk of adult-onset asthma when exposed to SHS. SHS exposure has dose-dependent synergism with family history of asthma, the joint effect being stronger with higher exposure levels. Avoiding SHS could be an important preventive measure for reducing the risk of adult-onset asthma among those with asthmatic heredity. Asking about family history of asthma is a useful tool for identifying these susceptible individuals in clinical and preventive settings.

Background: The epidemiological evidence linking socioeconomic deprivation with adverse pregnancy outcomes has been conflicting mainly due to poor measurement of socioeconomic status (SES). Studies have also failed to evaluate the plausible pathways through which socioeconomic disadvantage impacts on pregnancy outcomes. We investigated the importance of maternal SES as determinant of birth weight and gestational duration in an urban area and evaluated main causal pathways for the influence of SES., Methods: A population-based cross-sectional study was conducted among 559 mothers accessing postnatal services at the four main health facilities in Cape Coast, Ghana in 2011. Information on socioeconomic characteristics of the mothers was collected in a structured questionnaire., Results: In multivariate linear regression adjusting for maternal age, parity and gender of newborn, low SES resulted in 292 g (95% CI: 440-145) reduction in birth weight. Important SES-related determinants were neighborhood poverty (221 g; 95% CI: 355-87), low education (187 g; 95% CI: 355-20), studentship during pregnancy (291 g; 95% CI: 506-76) and low income (147 g; 95% CI: 277-17). In causal pathway analysis, malaria infection (6-20%), poor nutrition (2-51%) and indoor air pollution (10-62%) mediated substantial proportions of the observed effects of socioeconomic deprivation on birth weight. Generalized linear models adjusting for confounders indicated a 218% (RR: 3.18; 95% CI: 1.41-7.21) risk increase of LBW and 83% (RR: 1.83; 95% CI: 1.31-2.56) of PTB among low income mothers. Low and middle SES was associated with 357% (RR: 4.57; 95% CI: 1.67-12.49) and 278% (RR: 3.78; 95% CI: 1.39-10.27) increased risk of LBW respectively. Malaria infection, poor nutrition and indoor air pollution respectively mediated 10-21%, 16-44% and 31-52% of the observed effects of socioeconomic disadvantage on LBW risk., Conclusion: We provide evidence of the effects of socioeconomic deprivation, substantially mediated by malaria infection, poor nutrition and indoor air pollution, on pregnancy outcomes in a developing country setting.

Background: Atopic diseases, including allergic rhinitis, allergic dermatitis and asthma, are common diseases with a prevalence of 30-40% worldwide and are thus of great global public health importance. Allergic inflammation may influence the immunity against infections, so atopic individuals could be susceptible to respiratory infections. No previous population-based study has addressed the relation between atopy and respiratory infections in adulthood. We assessed the relation between atopic disease, specific IgE antibodies and the occurrence of upper and lower respiratory infections in the past 12 months among working-aged adults., Methods and Findings: A population-based cross-sectional study of 1008 atopic and non-atopic adults 21-63 years old was conducted. Information on atopic diseases, allergy tests and respiratory infections was collected by a questionnaire. Specific IgE antibodies to common aeroallergens were measured in serum. Adults with atopic disease had a significantly increased risk of lower respiratory tract infections (LRTI; including acute bronchitis and pneumonia) with an adjusted risk ratio (RR) 2.24 (95% confidence interval [CI] 1.43, 3.52) and upper respiratory tract infections (URTI; including common cold, sinusitis, tonsillitis, and otitis media) with an adjusted RR 1.55 (1.14, 2.10). The risk of LRTIs increased with increasing level of specific IgE (linear trend P = 0.059)., Conclusions: This study provides new evidence that working-aged adults with atopic disease experience significantly more LRTIs and URTIs than non-atopics. The occurrence of respiratory infections increased with increasing levels of specific IgE antibodies to common aeroallergens, showing a dose-response pattern with LRTIs. From the clinical point of view it is important to recognize that those with atopies are a risk group for respiratory infections, including more severe LRTIs.

Objective: To examine the effects of extremely cold and hot temperatures on ischaemic heart disease (IHD) mortality in five cities (Beijing, Tianjin, Shanghai, Wuhan and Guangzhou) in China; and to examine the time relationships between cold and hot temperatures and IHD mortality for each city., Design: A negative binomial regression model combined with a distributed lag non-linear model was used to examine city-specific temperature effects on IHD mortality up to 20 lag days. A meta-analysis was used to pool the cold effects and hot effects across the five cities., Patients: 16 559 IHD deaths were monitored by a sentinel surveillance system in five cities during 2004-2008., Results: The relationships between temperature and IHD mortality were non-linear in all five cities. The minimum-mortality temperatures in northern cities were lower than in southern cities. In Beijing, Tianjin and Guangzhou, the effects of extremely cold temperatures were delayed, while Shanghai and Wuhan had immediate cold effects. The effects of extremely hot temperatures appeared immediately in all the cities except Wuhan. Meta-analysis showed that IHD mortality increased 48% at the 1st percentile of temperature (extremely cold temperature) compared with the 10th percentile, while IHD mortality increased 18% at the 99th percentile of temperature (extremely hot temperature) compared with the 90th percentile., Conclusions: Results indicate that both extremely cold and hot temperatures increase IHD mortality in China. Each city has its characteristics of heat effects on IHD mortality. The policy for response to climate change should consider local climate-IHD mortality relationships.

Cooking oil fumes (COF) contain polycyclic aromatic hydrocarbons (PAHs), heterocyclic aromatic amines, benzene, and formaldehyde, which may cause oxidative damages to DNA and lipids. We assessed the relations between exposure to COF and subsequent oxidative DNA damage and lipid peroxidation among military cooks and office-based soldiers. The study population, including 61 Taiwanese male military cooks and a reference group of 37 office soldiers, collected urine samples pre-shift of the first weekday and post-shift of the fifth workday. We measured airborne particulate PAHs in military kitchens and offices and concentrations of urinary 1-OHP, a biomarker of PAH exposure, urinary 8-hydroxydeoxyguanosine (8-OHdG), a biomarkers of oxidative DNA damage, and urinary isoprostane (Isop). Airborne particulate PAHs levels in kitchens significantly exceeded those in office areas. The concentrations of urinary 1-OHP among military cooks increased significantly after 5 days of exposure to COF. Using generalized estimating equation analysis adjusting for confounding, a change in log(8-OHdG) and log(Isop) were statistically significantly related to a unit change in log(1-OHP) (regression coefficient (β), β=0.06, 95% CI 0.001-0.12) and (β=0.07, 95% CI 0.001-0.13), respectively. Exposure to PAHs, or other compounds in cooking oil fumes, may cause both oxidative DNA damage and lipid peroxidation.

Background: Effect of indoor air pollution (IAP) on birth weight remains largely unexplored but yet purported as the most important environmental exposure for pregnant women in developing countries due to the effects of second-hand smoke. We investigated the associations between the determinants of indoor air quality in households and birth weight., Methods: A cross-sectional study of 592 mothers and their newborns using postnatal services at the Korle Bu Teaching Hospital located in Accra, Ghana was conducted in 2010 to collect information on characteristics of indoor environment and other potential determinants of fetal growth. Birth weight was recorded from hospital records., Results: Household cooking fuel choices and garbage burning practices were determinants of birth weight. Multivariate linear regression analysis adjusting for age, social class, marital status and gravidity of mothers, and sex of neonate resulted in a 243 g (95% CI: 496, 11) and 178g (95% CI: 421, 65) reduction in birth weight for use of charcoal, and garbage burning respectively compared with use of LPG only. The estimated reductions in birth weight was not statistically significant. Applying the ordinal scale exposure parameter nonetheless revealed a significant exposure-response relationship between maternal exposures from charcoal use and garbage burning, and birth weight. Generalized linear models adjusting for confounders resulted in a 41% (risk ratio [RR] = 1.41; 95% CI: 0.62, 3.23) and 195% (RR=2.95; 95% CI: 1.10, 7.92) increase in the risk of low birth weight (LBW) for use of charcoal, and garbage burning respectively compared with use of LPG only. A combination of charcoal use and household garbage burning during pregnancy on fetal growth resulted in a 429 g (95% CI: 259, 599) reduction in birth weight and 316% (RR=4.16; 95% CI: 2.02, 8.59) excess risk of LBW. Sensitivity analysis performed by restricting the analysis to term births produced similar results., Conclusions: Maternal use of charcoal as a cooking fuel during pregnancy and burning of garbage at home are strong determinants of average fetal growth and risk of LBW. Efforts to reduce maternal exposures to IAP are thus important to improve birth outcomes.

Background: Many studies have examined the association between ambient temperature and mortality. However, less evidence is available on the temperature effects on coronary heart disease (CHD) mortality, especially in China. In this study, we examined the relationship between ambient temperature and CHD mortality in Beijing, China during 2000 to 2011. In addition, we compared time series and time-stratified case-crossover models for the non-linear effects of temperature., Methods: We examined the effects of temperature on CHD mortality using both time series and time-stratified case-crossover models. We also assessed the effects of temperature on CHD mortality by subgroups: gender (female and male) and age (age > =65 and age < 65). We used a distributed lag non-linear model to examine the non-linear effects of temperature on CHD mortality up to 15 lag days. We used Akaike information criterion to assess the model fit for the two designs., Results: The time series models had a better model fit than time-stratified case-crossover models. Both designs showed that the relationships between temperature and group-specific CHD mortality were non-linear. Extreme cold and hot temperatures significantly increased the risk of CHD mortality. Hot effects were acute and short-term, while cold effects were delayed by two days and lasted for five days. The old people and women were more sensitive to extreme cold and hot temperatures than young and men., Conclusions: This study suggests that time series models performed better than time-stratified case-crossover models according to the model fit, even though they produced similar non-linear effects of temperature on CHD mortality. In addition, our findings indicate that extreme cold and hot temperatures increase the risk of CHD mortality in Beijing, China, particularly for women and old people.

Although many guidelines recommend regular exercise for adults with asthma, the empirical evidence on the effect of exercise on adult asthma has been inconsistent and there are no previous systematic reviews on this topic. To fill in this gap of knowledge, we synthesized the data on the effects of regular exercise on physical fitness, asthma control and quality of life of adult asthmatics. We performed a Medline search from 1980 through June 2011. In the systematic review we included all clinical trials that provided information on the effects of regular exercise on adult asthma. We conducted meta-analyses of maximal oxygen consumption (VO(2)max) and forced expiratory volume in 1 s (FEV(1)) based on 9 studies. A total of 11 studies were included in the analyses, but only 6 of them had a non-exercising reference group of asthmatics. The meta-analyses of randomized controlled trials showed that regular exercise significantly improved VO(2)max. There was no obvious improvement in lung function measurements. Some individual studies showed evidence of improvement in quality of life and asthma control. Meta-analyses provided evidence that regular physical exercise improves physical fitness of adult asthmatics. The results on effects on lung function were inconclusive. There is insufficient evidence to assess the effects of exercise on asthma control and quality of life.

Background: Asthma is among the most common chronic diseases in working-aged populations and occupational exposures are important causal agents. Our aims were to evaluate the best methods to assess occurrence, public health impact, and burden to society related to occupational or work-related asthma and to achieve comparable estimates for different populations., Methods: We addressed three central questions: 1: What is the best method to assess the occurrence of occupational asthma? We evaluated: 1) assessment of the occurrence of occupational asthma per se, and 2) assessment of adult-onset asthma and the population attributable fractions due to specific occupational exposures. 2: What are the best methods to assess public health impact and burden to society related to occupational or work-related asthma? We evaluated methods based on assessment of excess burden of disease due to specific occupational exposures. 3: How to achieve comparable estimates for different populations? We evaluated comparability of estimates of occurrence and burden attributable to occupational asthma based on different methods., Results: Assessment of the occurrence of occupational asthma per se can be used in countries with good coverage of the identification system for occupational asthma, i.e. countries with well-functioning occupational health services. Assessment based on adult-onset asthma and population attributable fractions due to specific occupational exposures is a good approach to estimate the occurrence of occupational asthma at the population level. For assessment of public health impact from work-related asthma we recommend assessing excess burden of disease due to specific occupational exposures, including excess incidence of asthma complemented by an assessment of disability from it. International comparability of estimates can be best achieved by methods based on population attributable fractions., Conclusions: Public health impact assessment for occupational asthma is central in prevention and health policy planning and could be improved by purposeful development of methods for assessing health benefits from preventive actions. Registry-based methods are suitable for evaluating time-trends of occurrence at a given population but for international comparisons they face serious limitations. Assessment of excess burden of disease due to specific occupational exposure is a useful measure, when there is valid information on population exposure and attributable fractions.

Background: Few epidemiological studies that have assessed the relation between water disinfection by-products (DBPs) and the risk of stillbirth provide inconsistent results. The objective was to assess the relation between exposure to water disinfection by-products and the risk of stillbirth., Methods: We conducted a population-based case-control study of 3,289 cases of stillbirth and a random sample of 32,890 control subjects from 396,049 Taiwanese newborns in 2001-2003 using information from the Birth Registry and Waterworks Registry in Taiwan. We compared the risk of stillbirth in four disinfection by-product exposure categories based on the levels of total trihalomethanes (TTHMs) representing high (TTHMs 20+ µg/L), medium (TTHMs 10-19 µg/L), low exposure (TTHMs 5-9 µg/L), and 0-4 µg/L as the reference category. In addition, we conducted a meta-analysis of the results from the present and 5 previous studies focusing on stillbirth., Findings: In logistic regression analysis adjusting for gender, maternal age, plurality, conception of season and population density of the municipality where the mother lived during pregnancy, the odds ratio (OR) for stillbirth was 1.10 (95% CI 1.00-1.21) for medium exposure and 1.06 (95% 0.96-1.17) for high exposure compared to reference category. In the meta-analysis, the summary odds ratio for stillbirth (1.11, 95% CI: 1.03, 1.19) was consistently elevated., Conclusions: The present study is consistent with the hypothesis that the risk of stillbirth is related to prenatal exposure to disinfection by-products. This finding on stillbirth is consistent with previous epidemiologic studies, which strengthens the weight of evidence.

Introduction: Pesticide poisoning is an important public health problem worldwide. The study aimed to determine the risk of all-cause and cause-specific inpatient mortality and to identify prognostic factors for inpatient mortality associated with unintentional insecticide and herbicide pesticide poisonings., Methods: We performed a retrospective cohort study of 3,986 inpatients recruited at hospitalization between 1999 and 2008 in Taiwan. We used the International Classification of Disease, 9th ed., Clinical Modification external causes of injury codes to classify poisoning agents into accidental poisoning by insecticides and herbicides. Comparisons in mortality rates were made between insecticide poisoning patients and herbicide poisoning patients by using the Cox proportional hazards models to estimate multivariable-adjusted hazard ratios (HRs) and their 95% confidence intervals (CIs)., Results: There were 168 deaths during 21,583 person-days of follow-up evaluation (7.8 per 1,000 person-days). The major causes of mortality for insecticide poisonings were the toxic effect of organophosphate and coma, and the major causes of mortality for herbicide poisonings were the toxic effect of other pesticides and the toxic effect of organophosphate. The mortality for herbicide exposure was fourfold higher than that for insecticide exposure. The factors associated with inpatient mortality were herbicide poisonings (HR = 4.58, 95% CI 3.29 to 6.37) and receiving mechanical ventilation treatment (HR = 3.85, 95% CI 2.73 to 5.42)., Conclusions: We demonstrated that herbicides stand out as the dominant agent for poisoning-related fatalities. The control of and limiting access to herbicide agents and developing appropriate therapeutic regimens, including emergency care, should be priorities.

Background: There is accumulating epidemiologic evidence that exposure to traffic-related air pollutants, including particulate matter (PM) and polyaromatic hydro carbons (PAHs), plays a role in etiology and prognosis of a large scale of illnesses, although the role of specific causal agents and underlying mechanisms for different health outcomes remains unknown., Objective: Our general objective was to assess the relations between personal exposure to traffic exhausts, in particular ambient PM(2.5) and PAHs, and the occurrence of DNA strand breaks by applying personal monitoring of PM and biomarkers of exposure (urinary 1-hydroxypyrene-glucuronide, 1-OHPG) and effect (urinary 8-hydroxydeoxyguanosine, 8-OHdG and DNA strand breaks)., Methods: We recruited 91 traffic conductors and 53 indoor office workers between May 2009 and June 2011 in Taipei City, Taiwan. We used PM(2.5) personal samplers to collect breathing-zone particulate PAHs samples. Spot urine and blood samples after work shift of 2 consecutive days were analyzed for 1-OHPG, 8-OHdG and DNA strand breaks, respectively. Statistical methods included linear regression and mixed models., Results: Urinary 8-OHdG levels and the occurrence of DNA strand breaks in traffic conductors significantly exceeded those in indoor office workers in mixed models. Particulate PAHs levels showed a positive association with urinary 1-OHPG in the regression model (β = 0.056, p = 0.01). Urinary 1-OHPG levels were significantly associated with urinary 8-OHdG levels in the mixed model (β = 0.101, p = 0.023). Our results provide evidence that exposure to fine particulates causes DNA damage. Further, particulate PAHs could be biologically active constituents of PM(2.5) with reference to the induction of oxidative DNA damages.

Context: Studies from different geographical regions have assessed the relations between indoor dampness and mold problems and the risk of asthma, but the evidence has been inconclusive., Objective: To assess the relations between indicators of indoor dampness and mold problems and the risk of developing new asthma, and to investigate whether such relations differ according to the type of exposure., Data Sources: A systematic literature search of PubMed database from 1990 through March 2012 and the reference lists of recent reviews and of relevant articles identified in our search., Study Selection: Cohort/longitudinal and incident case-control studies assessing the relation between mold/dampness and new asthma were included., Data Extraction: Three authors independently evaluated eligible articles and extracted relevant information using a structured form., Synthesis: SIXTEEN STUDIES WERE INCLUDED: 11 cohort and 5 incident case-control studies. The summary effect estimates (EE) based on the highest and lowest estimates for the relation between any exposure and onset of asthma were for the highest estimates 1.48 (95% confidence interval [CI] 1.23-1.78, random-effects model, Q-statistic 38.75 (16), P = 0.001) ; and for the lowest estimates: 1.27 (95% CI 1.06-1.53, random-effects model, Q-statistic 38.12 (16), P = 0.000) [corrected].The summary effect estimates were significantly elevated for dampness (fixed-effects model: EE 1.33, 95% CI 1.12-1.56, Q-statistic 8.22 (9), P = 0.413), visible mold (random-effects model; EE 1.29, 95% CI 1.04-1.60, 30.30 (12), P = 0.001), and mold odor (random-effects model; EE 1.73, 95% CI 1.19-2.50, Q-statistics 14.85 (8), P = 0.038), but not for water damage (fixed-effects model; EE 1.12, 95% CI 0.98-1.27). Heterogeneity was observed in the study-specific effect estimates., Conclusion: The evidence indicates that dampness and molds in the home are determinants of developing asthma. The association of the presence of visible mold and especially mold odor to the risk of asthma points towards mold-related causal agents.

Passive smoking leads to exposure to carcinogenic, teratogenic, irritant and toxic substances of tobacco smoke as a consequence of other people's smoking. There is strong evidence that passive smoking causes several diseases of major public health importance as well as leads to exacerbations of many diseases. Among children passive smoking increases the risk of middle ear infections, lower respiratory infections, asthma and sudden infant death syndrome, and among adults asthma, COPD, lung cancer and cardiovascular diseases. Passive smoking by pregnant mothers leads to impaired fetal growth and may lead to organ system developmental disturbances. Asking about passive smoking and giving professional advice about stopping such exposure should be part of evidence-based medicine for these diseases. Health care workers have a central role in the prevention of passive smoking in clinical practice and health education.

There is inconclusive evidence suggesting a possible association of asthma with increased risk of caries. The authors conducted a systematic review and meta-analysis to synthesize the evidence on the relation between asthma and caries. They performed an Ovid Medline (US National Library of Medicine) database search of literature published from 1950 through May 2010 using the Medical Subject Headings "asthma" and "caries." Summary effect estimates were calculated with fixed- and random-effects models, and determinants of heterogeneity were studied in meta-regression analysis. The meta-analysis was based on 11 articles providing estimates of the effect of asthma on primary dentition and 14 articles on permanent dentition. Summary effect estimates for the relation between asthma and caries from the random-effects models were 2.73 (95% confidence interval: 1.61, 4.64) and 2.04 (95% confidence interval: 1.44, 2.89), respectively. Factors identified as determinants of heterogeneity were geographic region for primary dentition and publication year, sample size, asthma definition, and information on the use of asthma medication for permanent dentition. Evidence from this analysis suggests that asthma doubles the risk of caries in both primary and permanent dentition. Publication bias diagnostics and simulation suggested possible overestimation of the summary odds ratio for permanent dentition but not for primary dentition. Physicians and dentists should recommend preventive measures against caries for persons with asthma.

Background: There is limited evidence suggesting that prenatal exposure to ambient air pollutants may increase the risk of stillbirth, but previous epidemiological studies have not elaborated the most susceptible gestational period for the effects of air pollution exposure on stillbirth., Objectives: We estimated associations between exposure to ambient air pollutants and stillbirth, with special reference to the assessment of gestational periods when the fetus is most susceptible., Methods: We conducted a population-based case-control study in Taiwan. The case group consisted of 9,325 stillbirths, and the control group included 93,250 births randomly selected from 1,510,064 Taiwanese singleton newborns in 2001-2007. Adjusted logistic regression models were used to estimate odds ratios (ORs) per 10-ppb change for ozone and nitrogen dioxide, 1-ppb change for sulfur dioxide (SO2), 10-μg/m3 change for particulate matter with aerodynamic diameter ≤ 10 μm (PM10), and 100-ppb change for carbon monoxide during different gestational periods and according to term or preterm (< 37 weeks) birth status., Results: Stillbirth increased in association with a 1-ppb increase in first-trimester SO2 [adjusted OR = 1.02; 95% confidence interval (CI), 1.00-1.04], particularly among preterm births (adjusted OR = 1.04; 95% CI, 1.01-1.07). Stillbirth was also associated with a 10-μg/m3 increase in PM10 during the first (adjusted OR = 1.02; 95% CI, 1.00-1.05) and second (adjusted OR = 1.02; 95% CI, 1.00-1.04) month of gestation, and, as with SO2, associations appeared to be restricted to preterm births (first-trimester adjusted OR = 1.03; 95% CI, 1.00-1.07)., Conclusion: The study provides evidence that exposure to outdoor air SO2 and PM10 may increase the risk of stillbirth, especially among preterm births, and that the most susceptible time periods for exposure are during the first trimester of gestation.

The objective of the study was to identify factors which predispose women to smoking relapse postpartum and the factors that prevent the relapse, in order to design effective interventions to reduce the rate of smoking relapse after delivery. A prospective cohort study was conducted in 2004 and 2005 in Lodz, Poland. One hundred thirty-eight women who quit smoking for the pregnancy period were enrolled into the study between 32 and 36 weeks of pregnancy and were followed up at 3 months after delivery. Self-reported non-smoking status at enrollment and postpartum was verified using saliva cotinine level analyzed by liquid chromatography with tandem mass spectrometry (LC-MS/MS). The cut-off point of 10 ng/ml was adopted for the saliva cotinine level. About half of the study population relapsed into smoking within 3 months after delivery. Most (49%) relapses occurred in the first 4 weeks postpartum. Three factors were identified as directly influencing smoking relapse after delivery: need to cope with stressful situations (OR = 4.7; 95% CI 1.7-14.3), type of quitting attempt (OR = 4.0; 95% CI 1.1-16.1), and smoking environment at home (OR = 7.2; 95% CI 2.2-28.3). These three factors accounted for 84.0% (95% CI 52.7-96.1) of relapses. The profile of women who relapse to smoking after delivery can be described as quitting smoking only for pregnancy and postpartum period, resorting to smoking in response to stressful situations, and living with smokers. Those factors should be taken into account while conducting antismoking intervention for pregnant and postpartum women.

Purpose: The aims of this study were to investigate the relations of occupational exposures in tile industry to lung function and to evaluate potential interaction between smoking and tile dust exposure containing silica., Methods: A cross-sectional study of 232 workers (response rate 100%) in a tile factory and 76 office workers (response rate 73%) from four factories in Thailand was conducted in 2006-2007. Participants answered a questionnaire and performed spirometry., Results: Factory workers had lower spirometric functions than office workers, especially those with high dust exposure. There was a dose-response relation between duration of dust exposure and FEV1 and FVC, the adjusted effect of ≥ 21 years of exposure on FEV1 being -240 ml (-100 to -380) and on FVC -300 ml (-140 to -460). The adverse effect of dust on lung function was larger in current smokers suggesting synergism between smoking and tile dust exposure., Conclusions: This study provides evidence that long-term exposure to dust in tile industry is related to lung function reduction. There was a suggestion of synergistic effect between dust exposure and smoking. Tile factories should consider measures to reduce dust exposure and arrange spirometry surveillance for workers with such exposure. Smoking cessation should be promoted to prevent harmful effects of occupational tile dust exposure.

Background: Respiratory infections in early life are associated with an increased risk of developing asthma but there is little evidence on the role of infections for onset of asthma in adults. The objective of this study was to assess the relation of the occurrence of respiratory infections in the past 12 months to adult-onset asthma in a population-based incident case-control study of adults 21-63 years of age., Methods/principal Findings: We recruited all new clinically diagnosed cases of asthma (n = 521) during a 2.5-year study period and randomly selected controls (n = 932) in a geographically defined area in South Finland. Information on respiratory infections was collected by a self-administered questionnaire. The diagnosis of asthma was based on symptoms and reversible airflow obstruction in lung function measurements. The risk of asthma onset was strongly increased in subjects who had experienced in the preceding 12 months lower respiratory tract infections (including acute bronchitis and pneumonia) with an adjusted odds ratio (OR) 7.18 (95% confidence interval [CI] 5.16-9.99), or upper respiratory tract infections (including common cold, sinusitis, tonsillitis, and otitis media) with an adjusted OR 2.26 (95% CI 1.72-2.97). Individuals with personal atopy and/or parental atopy were more susceptible to the effects of respiratory infections on asthma onset than non-atopic persons., Conclusions/significance: This study provides new evidence that recently experienced respiratory infections are a strong determinant for adult-onset asthma. Reducing such infections might prevent onset of asthma in adulthood, especially in individuals with atopy or hereditary propensity to it.

The authors assessed the relation between exposure to dampness and molds in dwellings and the development of allergic rhinitis in childhood in a 6-year, population-based prospective cohort study of 1,863 children aged 1-7 years at baseline in 1991 (follow-up rate, 77%) from Espoo, Finland. The studied exposures were history of water damage, presence of moisture and visible mold, and perceived mold odor in the home, based on parent-administered questionnaire. A total of 246 (13.2%) children developed physician-diagnosed allergic rhinitis during the study period, resulting in an incidence rate of 440 cases per 10,000 person-years (95% confidence interval (CI): 387, 499). In logistic regression adjusting for confounding, any mold or dampness exposure indicator at baseline (adjusted odds ratio = 1.55, 95% CI: 1.10, 2.18), at follow-up (adjusted odds ratio = 1.62, 95% CI: 1.21, 2.18), or both (adjusted odds ratio = 1.96, 95% CI: 1.29, 2.98) was an important independent determinant of the risk of allergic rhinitis. Of the individual indicators, water damage and moisture on the surfaces were consistent determinants of allergic rhinitis. The results of this cohort study, which assessed exposure before the onset of allergic rhinitis, strengthen considerably the evidence of the role of indoor dampness problems as determinants of allergic rhinitis in children.

Background: A substantial number of epidemiologic studies have provided estimates of the relation between exposure to benzene at work and the risk of leukemia, but the results have been heterogeneous. To bridge this gap in knowledge, we synthesized the existing epidemiologic evidence on the relation between occupational exposure to benzene and the risk of leukemia, including all types combined and the four main subgroups acute myeloid leukemia (AML), acute lymphocytic leukemia (ALL), chronic lymphocytic leukemia (CLL), and chronic myeloid leukemia (CML)., Methods: A systematic literature review was carried out using two databases 'Medline' and 'Embase' from 1950 through to July 2009. We selected articles which provided information that can be used to estimate the relation between benzene exposure and cancer risk (effect size)., Results: In total 15 studies were identified in the search, providing 16 effect estimates for the main analysis. The summary effect size for any leukemia from the fixed-effects model was 1.40 (95% CI, 1.23-1.57), but the study-specific estimates were strongly heterogeneous (I2 = 56.5%, Q stat = 34.47, p = 0.003). The random-effects model yielded a summary- effect size estimate of 1.72 (95% CI, 1.37-2.17). Effect estimates from 9 studies were based on cumulative exposures. In these studies the risk of leukemia increased with a dose-response pattern with a summary-effect estimate of 1.64 (95% CI, 1.13-2.39) for low (< 40 ppm-years), 1.90 (95% CI, 1.26-2.89) for medium (40-99.9 ppm-years), and 2.62 (95% CI, 1.57-4.39) for high exposure category (> 100 ppm-years). In a meta-regression, the trend was statistically significant (P = 0.015). Use of cumulative exposure eliminated heterogeneity. The risk of AML also increased from low (1.94, 95% CI, 0.95-3.95), medium (2.32, 95% CI, 0.91-5.94) to high exposure category (3.20, 95% CI, 1.09-9.45), but the trend was not statistically significant., Conclusions: Our study provides consistent evidence that exposure to benzene at work increases the risk of leukemia with a dose-response pattern. There was some evidence of an increased risk of AML and CLL. The meta-analysis indicated a lack of association between benzene exposure and the risk of CML.

Background: Laboratory workers are commonly exposed to chemical, biological and physical agents. They also may adopt poor postures for long periods and be engaged in moving and handling. These factors may increase the risk of adverse pregnancy outcome in female laboratory workers., Aims: To assess whether laboratory work during pregnancy increases the risk of adverse pregnancy outcomes., Methods: The 1990-2006 Finnish Medical Birth Registry was used to identify all singleton newborns of all Finnish laboratory workers (n = 5425) and those of teachers (n = 21,438) as the reference population. The main outcomes were sexual differentiation (female gender), low birth weight, high birth weight, preterm delivery, post-term delivery, small-for-gestational age (SGA), large-for-gestational age and perinatal death. The generalized estimating equation (GEE) analysis was used to estimate odds ratios (ORs) adjusted for maternal age, parity, marital status and maternal smoking during pregnancy., Results: In the GEE analysis, the risk of low birth weight (adjusted OR: 1.27, 95% CI: 1.08-1.45) and SGA (adjusted OR: 1.27, 95% CI: 1.02-1.52) was higher in laboratory workers than in teachers. Correspondingly the prevalence of high birth weight (> or = 4000 g) was lower in newborns of laboratory workers (adjusted OR: 0.90, 95% CI: 0.83-0.98). The prevalence of post-term deliveries was close to being significantly higher among newborns of laboratory workers (adjusted OR: 1.16, 95% CI: 1.00-1.31)., Conclusions: This large population-based study provides evidence that laboratory work may be associated with reduced foetal growth.

Objective: To assess whether work as a nurse and a midwife during pregnancy increases the risk of adverse pregnancy outcomes., Methods: We identified from the 1990-2006 Finnish Medical Birth Registry all singleton births to nurses (n=109,542), midwives (n=3,009), and teachers (n=23,454) (referents). The main outcomes were sexual differentiation, low and high birth weight, preterm and postterm delivery, small and large for gestational age, and perinatal death., Results: The prevalence of low birth weight (2.9% vs. 2.5%), preterm delivery (4.4% vs. 4.1%), postterm delivery (4.7% vs. 4.1%), small for gestational age (1.8% vs. 1.4%), perinatal death (0.45% vs. 0.41%) and stillbirth (0.30% vs. 0.25%) was higher among the newborns of nurses than those of teachers. The adjusted odds ratio (OR) from generalized estimating equations was 1.17 (95% confidence interval [CI] 1.07-1.26) for low birth weight, 1.09 (95% CI 1.02-1.16) for preterm delivery, 1.11 (95% CI 1.03-1.18) for postterm delivery, 1.17 (95% CI 1.05-1.30) for small for gestational age, 1.12 (95% CI 0.90-1.35) for perinatal death, and 1.27 (95% CI 0.98-1.56) for stillbirth. For midwives, the risk of small for gestational age (OR=1.25, 95% CI 0.95-1.55) was elevated, but the 95% CI included unity. There was no substantial difference in the sex distribution., Conclusions: This study provides evidence that work as a nurse may reduce fetal growth and duration of pregnancy. The inference is based on the newborns of teachers as the reference group. However, the prevalence of most of the outcomes was higher among the newborns of all other working women combined than in the newborns of both nurses and teachers.

Background: Hairdressers and cosmetologists are commonly exposed to chemicals, poor posture and psychological stress that may increase the risk of adverse pregnancy outcomes., Aims: To assess whether work as a hairdresser and cosmetologist during pregnancy increases the risk of low birth weight, preterm delivery, small for gestational age (SGA) and perinatal death., Methods: The 1990-2004 Finnish Medical Birth Registry was used to identify all singletons of hairdressers (n = 10 622) and cosmetologists (n = 2490) and those of teachers (n = 18 594) as the reference group. The main outcomes were sexual differentiation measured as the probability of female gender, low birth weight, preterm delivery, SGA and perinatal death. Logistic regression analysis was used to estimate odds ratios (ORs) adjusted for maternal age, parity, marital status and maternal smoking during pregnancy., Results: In logistic regression, the risk of low birth weight (adjusted OR 1.44, 95% CI 1.23-1.69), preterm delivery (adjusted OR 1.21, 95% CI 1.07-1.38), SGA (adjusted OR 1.65, 95% CI 1.38-2.07) and perinatal death (adjusted OR 1.62, 95% CI 1.01-1.60) was higher in hairdressers than in teachers. In cosmetologists, the risk of SGA (adjusted OR 1.53, 95% CI 1.10-2.12) and perinatal death (adjusted OR 1.36, 95% CI 0.62-2.98) was elevated. There were no substantial differences in the sex distribution., Conclusions: This study provides evidence that work as a hairdresser or cosmetologist may reduce foetal growth. Work as a hairdresser may also increase the risk of preterm delivery and perinatal death.

Objective: We assessed whether paternal exposure prior to conception and maternal exposure during pregnancy to welding fumes (WF) and metal dusts or fumes (MD/F) independently and jointly increases the risk of preterm delivery, low birth weight, and small-for-gestational age., Methods: The study population was selected from The Finnish Prenatal Environment and Health Study of 2,568 newborns (response rate 94%) and included 1,670 women who worked during pregnancy of which 68 were exposed either to WF and/or MD/F., Results: The risk of SGA was related to maternal exposure to WF only (adjusted OR = 1.78; 95% CI 0.53-5.99), MD/F only (adjusted OR = 1.77; 95% CI 0.38-8.35) and both exposures (2.92; 1.26-6.78). The corresponding effect estimates for preterm delivery were 2.66 (0.32-22.08), 5.64 (1.14-27.81) and for birth weight below 3,000 g 3.79 (1.09-13.19), 1.85 (0.56-6.14) and 1.70 (0.70-4.15), respectively. There was some suggestive, inconsistent evidence that the risk of preterm delivery and SGA is related to paternal exposure to WF., Conclusions: The present results provide evidence that maternal exposure to WF or MD/F combination during pregnancy may reduce fetal growth and suggestive evidence that paternal exposure to WF may increase the risk of preterm delivery and small-for-gestational age. The small number of exposed women and the lack of data for exposure concentrations suggest the need for further study to verify our findings.

Work as a physician may be related to several occupational hazards. Only few studies have investigated the relations between work as a physician and the risk of adverse pregnancy outcomes and the results have been inconsistent. We conducted a nationwide population-based study in Finland to assess whether work as a physician during pregnancy increases the risk of adverse pregnancy outcomes. We identified from the 1990 to 2006 Finnish Medical Birth Register data all singleton newborns of physicians (N = 7,642) and other upper white collar workers (N = 124,606; as the reference group) from a source population of 946,392 singleton newborns. In generalized estimating equations, work as a physician was not related to low birth weight (adjusted odds ratio (OR) 1.00, 95% confidence interval (CI 0.86-1.15), preterm delivery (1.00, 0.89-1.12), small-for-gestational age (1.04, 0.86-1.22), large-for-gestational age (1.00, 0.86-1.13), perinatal death (0.88, 0.49-1.27), and the female gender of the newborn (0.98, 0.94-1.03). The risk of high birth weight (4,000 g or more; 0.88, 0.84-0.93) and postterm delivery were lower (0.77, 0.65-0.89) among physicians than the reference group. The results indicate that Finnish female physicians have a similar risk of adverse pregnancy outcomes as women of similar socio-economic background.

Background: Air pollution influences the development of oral clefts in animals. There are few epidemiologic data on the relation of prenatal air pollution exposure and the risk of oral clefts., Objectives: Our goal in this study was to assess the relations between exposure to ambient air pollution and the risk of cleft lip with or without cleft palate (CL/P)., Methods: We conducted a population-based case-control study of all 653 cases of CL/P and a random sample of 6,530 control subjects from 721,289 Taiwanese newborns in 2001-2003. We used geographic information systems to form exposure parameters for sulfur dioxide, nitrogen oxides, ozone, carbon monoxide, and particulate matter with an aerodynamic diameter

The carbon composition of fine particles (PM(2.5)) from traffic exhausts may play a role in adverse health effects. The objective of this study was to assess the concentrations of elemental and organic carbon in PM(2.5) in traffic exhausts from different types of vehicles in the booths of Taiwanese toll station workers and estimate the relations between traffic density and carbon concentrations. Tollbooth indoor monitoring samples were collected for 10 days to assess the 8 h integrated PM(2.5) concentration. Particle samples were analyzed for the content of total carbon, and elemental, and organic carbon. The mean carbon concentrations in the bus and truck lanes were [total: 167.7 microg/m(3) (SD 79.8 microg/m(3)); elemental: 131.7 (66.2); organic: 36.0 (25.8)], substantially higher compared with the car lanes with cash payment [39.2 (29.5); 20.2 (19.5); 19.2 (14.6)] and the car lanes with ticket payment [34.1 (26.1); 15.8 (17.6); 18.5 (12.2)]. The increase in elemental carbon concentration per vehicle in the bus and truck lane was 14 and 9 times greater than that of car lanes of ticket payment and car lanes of cash payment. The mass fraction of carbonaceous species in PM(2.5) accounted for 54% in bus and truck lanes, whereas the corresponding figure was 30-31% for car lanes. Elemental carbon is an important component of diesel exhaust. Workers in toll stations are exposed to high levels of both elemental and organic carbon.

Background: Phthalates from polyvinyl chloride (PVC) plastics may have adverse effects on airways and immunologic systems, but the evidence has not been reviewed systematically., Objective: We reviewed the evidence for the role of exposure to phthalates from PVC products in the development of asthma and allergies., Methods: We conducted a Medline database search (1950 through May 2007) for relevant studies on the respiratory and allergic effects of exposure to phthalates from PVC products., Results: We based this review on 27 human and 14 laboratory toxicology studies. Two mouse inhalation experiments indicated that mono-2-ethylhexyl phthalate (MEHP) has the ability to modulate the immune response to exposure to a coallergen. The data suggested a no observed effect level of 30 microg MEHP/m3, calculated to be below the estimated level of human exposure in common environments. Case reports and series (n = 9) identified and verified cases of asthma that were very likely caused by fumes emitted from PVC film. Epidemiologic studies in adults (n = 10), mostly small studies in occupational settings, showed associations between heated PVC fumes and asthma and respiratory symptoms; studies in children (n = 5) showed an association between PVC surface materials in the home and the risk of asthma [fixed-effects model: summary odds ratio (OR), 1.55; 95% confidence interval (CI), 1.18-2.05; four studies] and allergies (OR, 1.32; 95% CI, 1.09-1.60; three studies)., Conclusions: High levels of phthalates from PVC products can modulate the murine immune response to a coallergen. Heated PVC fumes possibly contribute to development of asthma in adults. Epidemiologic studies in children show associations between indicators of phthalate exposure in the home and risk of asthma and allergies. The lack of objective exposure information limits the epidemiologic data.

Objective: We conducted a population-based study to assess whether work as a nurse during pregnancy increases the risk of low birth weight, preterm delivery, and small-for-gestational-age., Methods: The study population was selected from The Finnish Prenatal Environment and Health Study of 2568 newborns (response 94%) and included 128 (5.0%) newborns of nurses and 559 newborns of office workers (21.8%) as a reference group., Results: The risk of low birth weight (adjusted odds ratio = 1.02; 95% confidence interval = 0.32-3.22) and preterm delivery (0.81; 0.32-2.05) did not differ between newborns of nurses and office workers, but the risk of small-for-gestational-age was substantially higher among newborns of nurses (1.99; 1.10-3.59). This corresponds to a population attributable fraction of 2.5%., Conclusions: The results indicate that working as a nurse during pregnancy could reduce fetal growth.

Background: There is little information on potential differences in smoking behaviour of parents between Finland and Russia and on the effects of environmental tobacco smoke (ETS) exposure on allergic and respiratory diseases among Finnish and Russian children. The aim of the study was to compare the smoking behaviour of parents and school children and to assess the relations of tobacco smoke exposure during pregnancy and childhood with occurrence of allergic diseases and respiratory infections among school children., Methods: We conducted a population-based cross-sectional study in the neighbour towns across the border of Imatra in Finland and Svetogorsk in Russia. The study population consisted of 512 Finnish and 581 Russian school children aged 7-16 years (response rate 79%)., Results: Children's tobacco smoke exposure differed markedly between Finland and Russia. The risk of asthma was particularly related to high maternal smoking exposure during pregnancy (adjusted OR 3.51, 95% CI 1.00-12.3), infancy (3.34, 1.23-9.07) and currently (3.27, 1.26-8.48), and the risk of common cold was related to high combined parental smoking during infancy (1.83, 1.06-3.17) in Finnish children. Among Russian children allergic conjunctivitis was related to maternal smoking during infancy (4.53, 1.49-13.8) and currently (2.82, 1.07-7.44)., Conclusions: Smoking behaviour of parents and ETS exposure during childhood differed markedly between Finland and Russia. Asthma was particularly increased in relation to high exposure to maternal smoking in Finland. The results suggest that more efforts should be directed to reducing tobacco smoke exposure of children in both Finland and Russia. (250 words).

Background: Little is known about differences in allergic and respiratory diseases between the Finnish and Russian populations., Methods: We conducted a population-based cross-sectional study to compare the occurrence of allergic diseases and respiratory infections among school children in the towns of Imatra in Finland and Svetogorsk in Russia on either side of the common border. The study population consisted of 512 Finnish and 581 Russian school children aged 7-16 years (response rate 79%). We used multiple logistic regression analysis to calculate odds ratios adjusting for age and gender., Results: The prevalences of asthma (6.7 vs. 3.9%, adjusted odds ratio (OR) 1.54, 95% confidence interval (CI 0.87-2.71), allergic rhinitis (15.2 vs. 8.8%, OR 1.81, 1.22-2.68), allergic conjunctivitis (4.7 vs. 3.2%, 1.33, 0.70-2.53), and atopic dermatitis (10.5 vs. 5.9%, 1.78, 1.12-2.83) were substantially higher among school children in Imatra compared to those in Svetogorsk, but the symptoms were more severe among allergic Russian children. Tonsillitis (adjusted OR 0.11, 95% CI 0.07-0.17), sinusitis (0.39, 0.24-0.63), bronchitis (0.41, 0.27-0.62) and pneumonia (0.19, 0.04-0.90) occurred less frequently in the Finnish children, whereas otitis media (2.37, 1.55-3.62) and common cold (4.07, 3.12-5.31) were more frequent in Finland., Conclusions: Allergic diseases are more common in Finnish than Russian school children, but the symptoms are more severe among allergic Russian children. Respiratory infections are in general more frequent in Russian children. "Western" lifestyle habits, differences in diagnostic procedures and environmental factors, and availability of health care and medications are discussed as possible explanations for the observed differences.

Background: The question of the protective effect of breastfeeding on development of asthma has raised substantial interest, but the scientific evidence of the optimal duration of breastfeeding is controversial., Methods: The authors elaborated the optimal duration of breastfeeding with respect to the risk of asthma primarily, and secondarily to the risk of persistent wheezing, cough and phlegm in school age in a population-based cohort study with the baseline in 1991 and follow-up in 1997. The study population comprised 1984 children aged 7 to 14 years at the end of the follow-up (follow-up rate 77). Information on breastfeeding was based on the baseline survey and information on the health outcomes at the follow-up., Results: There was a U-shaped relation between breastfeeding and the outcomes with the lowest risk with breastfeeding from four to nine months for asthma and seven to nine months for persistent wheezing, cough and phlegm., Conclusion: Our results suggest a U shape relation between duration of breastfeeding and risk of asthma with an optimal duration of 4 to 6 months. A true concave relation would explain the inconsistent results from the previous studies.

Background: Organic solvents are among the most common exposures in the workplace. Our objective was to elaborate the relationship between prenatal occupational solvent exposure and fetal growth as well as duration of pregnancy, and to quantify the impact of occupational organic solvent exposure., Methods: We conducted a population-based study of 1670 singleton newborns of women who participated in The Finnish Prenatal Environment and Health Study after their delivery (response rate 94%) and who were working during pregnancy (65%). Exposure information was based on questions about exposure to solvents at work before and during pregnancy. The health outcomes, based on information from a questionnaire and the Finnish Medical Birth Registry, were low birth weight (<3000 g), small-for-gestational-age and preterm delivery (<37 weeks)., Results: In logistic regression analysis, the risk of the baby being small-for-gestational-age was related to any exposure to solvents 3 months before or during pregnancy with an adjusted odds ratio (OR) of 1.67 [95% confidence interval (CI) = 1.02-2.73]. Also the adjusted OR for low birth weight was elevated with exposure, although it did not reach statistical significance (1.17; 95% CI = 0.71-1.93). The population attributable fraction for small-for-gestational-age was 2.3% for all pregnant women., Conclusions: Work exposure to organic solvents may reduce intrauterine growth by increasing the risk of the baby being small-for-gestational-age.

Background: There is accumulating evidence that the type of work and environmental exposures in the working environment may have adverse effects on foetal development., Aim: To compare the risk of low birth weight (LBW), small-for-gestational age (SGA) and pre-term delivery (PD) in broad categories of maternal occupation including farming and forestry; factory, mining and construction; office, non-manual and service work and housewives., Methods: The study population consisted of 2568 singleton newborns of women who participated in The Finnish Prenatal Environment and Health Study after the delivery (response rate 94%). Information on maternal occupation and work during pregnancy was collected after the delivery. The health outcomes were LBW (<2500 g), SGA and PD (<37 weeks)., Results: In newborns of women working in factories, mining and construction, the risk of LBW (adjusted odds ratio [OR] 3.66, 95% confidence interval [CI] 1.15-11.62), SGA (adjusted OR 1.53, 95% CI 0.73-3.21), but not the risk of PD (adjusted OR 0.64, 95% CI 0.19-2.22), was higher compared with newborns of housewives. In newborns of farmers and forestry workers, the risks of PD (adjusted OR 2.38, 95% CI 1.01-5.65), LBW (adjusted OR 2.86, 95% CI 0.78-11.58) and SGA (adjusted OR 1.51, 95% CI 0.62-3.65) were all elevated. In office, non-manual and service workers, the corresponding estimates were lower (LBW: 1.62, 0.67-3.95; SGA: 1.45, 0.92-2.28; PD: 1.18, 0.69-2.01)., Conclusions: There were substantial differences in the risk of adverse pregnancy outcomes between the main branches of industry.

Background: Prenatal exposure to tobacco smoke through mother's smoking increases the risk of developing asthma later in life. A recent study suggested that this effect is present only in girls. We explored potential differences in susceptibility between boys and girls., Methods: We followed all 58,841 Finnish singleton babies born in 1987 through 5 nationwide registries for 7 years and identified all cases of doctor-diagnosed asthma (ICD-9 code 493). The birth registry provided categorical information on the mother's smoking during pregnancy: no smoking (reference), low exposure (<10 cigarettes per day), and high exposure (>10 cigarettes per day)., Results: In girls the cumulative incidence of asthma was 0.0245 in the reference group, 0.0310 in the low maternal smoking group (risk difference = 0.0065; 95% CI = 0.0053-0.0076), and 0.0360 in the high maternal smoking group (0.0115; 0.0096-0.0133). The corresponding cumulative incidences for boys were 0.0405, 0.0501 (0.0096; 0.0089-0.0103), and 0.0522 (0.0117; 0.0091-0.0142). In logistic regression analysis adjusting for confounding, the combined effect of male sex and high maternal smoking (compared with female sex and no smoking) was 112% excess risk. This corresponded closely to what would be expected from the additive independent effects of male sex (67% excess risk) and high maternal smoking (44% excess risk)., Conclusions: Effects of maternal smoking during pregnancy on the risk of developing asthma are similar in boys and girls, with no interaction on an additive scale.

Background: Office exposures have been linked to symptoms of sick building syndrome, but their relation to the development of asthma has not been studied previously. These exposures have increasing importance because an increasing proportion of the workforce is working in office environments., Objectives: The aim of this study was to assess the relations of exposure to carbonless copy paper (CCP), paper dust, and fumes from photocopiers and printers to adult-onset asthma., Methods: We conducted a population-based incident case-control study of adults 21-63 years of age living in the Pirkanmaa District in South Finland. All new clinically diagnosed cases (n = 521) of asthma were recruited during a 3-year study period. A random sample of the source population formed the controls (n = 1,016). This part focused on 133 cases and 316 controls who were office workers according to their current occupation classified by the 1988 International Standard Classification of Occupations. All participants answered a questionnaire on health, smoking, occupation, and exposures at work and home. Subjects with previous asthma were excluded., Results: Exposures to paper dust [adjusted odds ratio (OR) = 1.97; 95% confidence interval (CI), 1.25-3.10] and CCP (OR = 1.66; 95% CI, 1.03-2.66) were related to significantly increased risk of adult-onset asthma. An exposure-response relation was observed between exposure to paper dust and risk of asthma., Conclusions: This study provides new evidence that exposures to paper dust and CCP in office work are related to increased risk of adult-onset asthma. Reduction of these exposures could prevent asthma in office workers. Clinicians seeing asthma patients should be aware of this link to office exposures.

Objectives: To assess the relation between exposure to carbonless copy paper (CCP), paper dust, and fumes from photocopiers and printers (FPP), and the occurrence of sick building syndrome (SBS)-related symptoms, chronic respiratory symptoms and respiratory infections., Methods: A population-based cross-sectional study with a random sample of 1016 adults, 21-63 years old, living in Pirkanmaa District in South Finland was conducted. This study focused on 342 office workers classified as professionals, clerks or administrative personnel according to their current occupation by the International Standard Classification of Occupations-88. They answered a questionnaire about personal information, health, smoking, occupation, and exposures in the work environment and at home., Results: In logistic regression analyses adjusting for age, sex and a set of other confounders, all three exposures were related to a significantly increased risk of general symptoms (headache and fatigue). Exposure to paper dust and to FPP was associated with upper respiratory and skin symptoms, breathlessness, tonsillitis and middle ear infections. Exposure to CCP increased the risk of eye symptoms, chronic bronchitis and breathlessness. It was also associated with increased occurrence of sinus and middle ear infections and diarrhoea. A dose-response relations was observed between the number of exposures and occurrence of headache. The risk of tonsillitis and sinus infections also increased with increasing number of exposures. All chronic respiratory symptoms, apart from cough, were increased in the highest exposure category (including all three exposures)., Conclusions: This study provides new evidence that exposure to paper dust and to FPP is related to the risk of SBS symptoms, breathlessness and upper respiratory infections. It strengthens the evidence that exposure to CCP increases the risk of eye symptoms, general symptoms, chronic respiratory symptoms and some respiratory infections. Reduction of these exposures could improve the health of office workers.

The authors conducted a population-based incident case-control study to assess the relations between different types of interior surface materials and recent renovations at home and at work and the risk of asthma in adults. The authors systematically recruited all new cases of asthma during a 2.5-year study period (1997-2000) and randomly selected controls from a source population consisting of adults 21-63 years of age living in south Finland. The clinically diagnosed cases consisted of 521 adults with new asthma, and the controls consisted of 932 adults fulfilling eligibility criteria. In logistic regression analysis adjusting for confounding, the risk of asthma was related to the presence of plastic wall materials (adjusted odds ratio (OR) = 2.43, 95% confidence interval (CI): 1.03, 5.75) and wall-to-wall carpet at work (adjusted OR = 1.73, 95% CI: 0.74, 4.09), the latter in particular in the presence of mold problems (adjusted OR = 4.64, 95% CI: 1.11, 19.4). Use of floor-leveling plaster at home during the past 12 months was also a determinant of onset of asthma (adjusted OR = 1.81, 95% CI: 1.06, 3.08). These findings underline the need to consider the health aspects of materials used in floor, wall, and other indoor surfaces.

Background: Accumulating evidence suggests that reduced duration of pregnancy predicts increased risk of asthma, but the studies published have been inconsistent., Objective: We sought to synthesize the evidence on the relation between preterm delivery and the risk of asthma later in life and to assess differences between the studies as potential sources for heterogeneity of the results., Methods: We conducted a MEDLINE search (until the end of May 2005). The outcome was asthma. The determinant of interest was preterm delivery defined as a gestational age of less than 37 weeks., Results: We identified 19 articles that provided estimates for the meta-analysis. The summary effect estimates for asthma (fixed-effects odds ratio, 1.074 [95% CI, 1.072-1.075]; heterogeneity P = .000; random-effects odds ratio, 1.366 [95% CI, 1.303-1.432]) showed an increased risk in relation to preterm delivery, with substantial heterogeneity between study-specific estimates. The effect of preterm delivery on asthma was stronger in cross-sectional studies; studies with broad outcome criteria, a small sample size, and a younger study population; and studies conducted in English-speaking populations, outside Europe, and published more recently. In metaregression, adjusting for other determinants, the effect estimate was significantly associated only with the mean age of the study population., Conclusions: The weight of evidence shows that preterm babies have an increased risk of asthma compared with term babies., Clinical Implications: Recognition of prematurity as a determinant of asthma emphasizes the importance of active treatment of physiologic airflow obstruction and a need for special preventive measures against known environmental determinants of asthma in preterm babies.

The aims of this study were to review experiences with national or statewide smoke-free workplace legislation and data on the occurrence of environmental tobacco smoke (ETS) exposure at work, to present the best estimates for health effects related to workplace ETS exposure, and to calculate corresponding population attributable fractions (PAFs) for respiratory and cardiovascular diseases for 14 European countries and the USA. Systematic searches of the Medline database were carried out, with a cut-off date of November 2005. PAFs for the main outcomes were calculated from the best disease-specific effect estimates and country-specific prevalences of work ETS exposure. Significant numbers of workers are exposed to ETS at work, i.e. approximately 7.5 million workers in 15 European Union countries and 24.6 million in the USA. Workplace ETS exposure is causally linked to lung cancer and coronary heart disease, and is related to an increased risk of asthma in adults and reduced birthweight in newborns. Relatively strong evidence links ETS exposure to chronic obstructive pulmonary disease and stroke. PAFs in Europe and the USA showed that, at current workplace ETS exposure prevalences, the public health impact is substantial. Experience of national and statewide smoke-free workplace legislation from different countries shows that such legislation leads to significant reductions in employees' environmental tobacco smoke exposure at work, as well as improvements in respiratory and cardiac health.

We pooled the data from 6 case-control studies of bladder cancer with detailed information on fluid intake and water pollutants, particularly trihalomethanes (THM), and evaluated the bladder cancer risk associated with total and specific fluid consumption. The analysis included 2,729 cases and 5,150 controls. Odds ratios (OR) and 95% confidence intervals (CI) for fluid consumption were adjusted for age, gender, study, smoking status, occupation and education. Total fluid intake was associated with an increased risk of bladder cancer in men. The adjusted OR for 1 l/day increase in intake was 1.08, (95% CI 1.03-1.14, p-value for linear trend <0.001), while no trend was observed in women (OR=1.04, 0.94-1.15; p-value=0.7). OR was 1.33 (1.12-1.58) for men in the highest category of intake (>3.5 l/day) as compared to those in the lowest (2 l/day vs. 5 cups of coffee daily vs. <5 and for THM exposure, but neither exposure confounded or modified the OR for tap water intake. The association of bladder cancer with tap water consumption, but not with nontap water fluids, suggests that carcinogenic chemicals in tap water may explain the increased risk., (Copyright (c) 2005 Wiley-Liss, Inc.)

Purpose of Review: The purpose of this review is to summarize the recent evidence on the effect of cleaning jobs on asthma, based on case reports and series of occupational asthma among cleaners, and epidemiological studies on the relationship between different characteristics of cleaning and asthma risk, as well as to elaborate the evidence on potential occupational exposures responsible for the increased asthma risk observed in cleaners., Recent Findings: Six recent epidemiologic studies strengthen the evidence that domestic and industrial cleaners are at higher risk of asthma compared with professional employees in Europe and the United States. These studies take into account individual confounders, such as age and cigarette smoking. This finding is supported by case reports and registry-based studies of occupational asthma. The studies and reports have identified some chemicals, such as bleach, as specific causes of asthma. Increased risk of asthma has also been related to some specific job tasks, such as cleaning windows and washing dishes., Summary: Recent studies strengthen the evidence of an increased asthma risk among cleaners or individuals in other jobs in which they are involved in cleaning. Further research should be directed to elaborate how much of asthma is related to specific sensitization to certain chemicals and how much to airway inflammation induced by exposure to a mixture of irritants.