The burden of heat-related mortality attributable to recent human-induced climate change.

Climate change affects human health; however, there have been no large-scale, systematic efforts to quantify the heat-related human health impacts that have already occurred due to climate change. Here, we use empirical data from 732 locations in 43 countries to estimate the mortality burdens associated with the additional heat exposure that has resulted from recent human-induced warming, during the period 1991-2018. Across all study countries, we find that 37.0% (range 20.5-76.3%) of warm-season heat-related deaths can be attributed to anthropogenic climate change and that increased mortality is evident on every continent. Burdens varied geographically but were of the order of dozens to hundreds of deaths per year in many locations. Our findings support the urgent need for more ambitious mitigation and adaptation strategies to minimize the public health impacts of climate change.

Interleukin 6 SNP rs1800797 associates with the risk of adult-onset asthma.

Interleukin 6 (IL6) is an inflammatory cytokine that has been suggested to have an important role in the pathogenesis of asthma. IL6 single-nucleotide polymorphisms (SNPs) have been associated with levels of IL6, and with childhood and prevalent adult asthma. A recent study also suggested that IL6 SNPs associate especially with atopic asthma. However, association of IL6 SNPs with adult-onset asthma has not been studied. In a population-based study of 467 incident adult-onset asthma cases and 613 disease-free controls from South Finland, we analyzed association of 6 tagging SNPs of the IL6 locus with the risk of adult-onset asthma and with atopy. Asthma was clinically diagnosed, and atopy was defined based on Phadiatop test. IL6 SNP rs1800797 associated with the risk of adult-onset asthma in a log additive model, with adjusted odds ratio (aOR) 1.31 (95% confidence interval 1.09-1.57), and especially with the risk of atopic adult-onset asthma when compared with non-atopic controls, aOR 1.46 (95% CI 1.12-1.90). This is the first study to show an association of IL6 with adult-onset asthma, and especially with atopic adult-onset asthma.

Seasonality and temperature effects on fasting plasma glucose: A population-based longitudinal study in China.

AIMS: To examine the seasonality and effects of temperature on levels of fasting plasma glucose (FPG). METHODS: We collected health data from the Kailuan cohort study. FPG, blood pressure and individual information including age, gender, body mass index, smoking status, drinking habit, physical activities, income, work type, education level, and history of diabetes, were collected for each participant. Daily weather conditions were collected during the study period of 2006-2011. A total of 49,417 participants who had three times of health examination were included to the analyses. Generalized additive mixed models were used to examine the effects of temperature and seasonality on FPG levels, while controlling for potential confounders. RESULTS: FPG level was higher in winter and spring than that in autumn and summer. For all participants, the FPG winter level increased 0.31mmol/L [95% confidence interval (CI), 0.28-0.33mmol/L] in comparison with autumn. The association between temperature and FPG levels was U-shaped. For all participants, the change in FPG levels associated with extreme cold temperature (-6.7°C), moderate cold temperature (2.4°C), moderate hot temperature (23.7°C), and with extreme hot temperature (28.1°C), in comparison with threshold (18.1°C) were 0.12mmol/L (95% CI: 0.10-0.14mmol/L), 0.10 (95% CI: 0.09-0.12mmol/L), 0.06 (95% CI: 0.04-0.08mmol/L), and 0.12mmol/L (95% CI: 0.08-0.16mmol/L), respectively. CONCLUSION: The findings suggest that there may be strong relationships between FPG levels and season and ambient temperature. In particular, there were higher FPG levels in the winter and at extreme cold and hot temperatures.

Water disinfection by-products and bladder cancer: is there a European specificity? A pooled and meta-analysis of European case-control studies.

Several epidemiological studies suggested an association between the risk of bladder cancer and the exposure to trihalomethanes (THMs), the main disinfection by-products (DBPs) of chlorinated water. A previous pooled analysis of case-control studies from North America and Europe estimated a summarized dose-response relation. For policy guidance of drinking water disinfection in Europe and because major differences exist in water disinfection practices and DBPs occurrence between both continents, specific risk estimates for bladder cancer in relation to DBPs exposure for European populations were needed. We conducted a pooled and a two-stage random-effect meta-analyses of three European case-control studies from France, Finland, and Spain (5467 individuals: 2381 cases and 3086 controls). Individual exposure to THMs was calculated combining information on residential history, estimates of the average total THMs (TTHM) level in tap water at the successive residences and personal water consumption. A significant odds-ratio was observed for men exposed to an average residential TTHM level > 50 µg/l (OR = 1.47 (1.05; 2.05)) when compared to men exposed to levels ≤ 5 µg/l. The linear trend of the exposure-risk association was significant (p = 0.01). Risks increased significantly for exposure levels above 25 µg/l and with more than 30 years of exposure to chlorinated water, but were mainly driven by the level rather than the duration of exposure. No significant association was found among women or with cumulative exposure through ingestion. There was no evidence of a differential exposure-response relation for TTHM and bladder cancer in Europe and North America. Consequently, a global exposure-risk relation based on 4351 cases and 7055 controls is now available.

Laboratory work and adverse pregnancy outcomes.

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.

Impact of smoke-free workplace legislation on exposures and health: possibilities for prevention.

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.

Traffic related air pollution as a determinant of asthma among Taiwanese school children.

BACKGROUND: There is evidence that long term exposure to ambient air pollution increases the risk of childhood asthma, but the role of different sources and components needs further elaboration. To assess the effect of air pollutants on the risk of asthma among school children, a nationwide cross sectional study of 32 672 Taiwanese school children was conducted in 2001. METHODS: Routine air pollution monitoring data for sulphur dioxide (SO2), nitrogen oxides (NOx), ozone (O3), carbon monoxide (CO), and particles with an aerodynamic diameter of 10 microm or less (PM10) were used. Information on individual characteristics and indoor environments was from a parent administered questionnaire (response rate 93%). The exposure parameters were calculated using the mean of the 2000 monthly averages. The effect estimates were presented as odds ratios (ORs) per 10 ppb changes for SO2, NOx, and O3, 100 ppb changes for CO, and 10 microg/m3 changes for PM10. RESULTS: In a two stage hierarchical model adjusting for confounding, the risk of childhood asthma was positively associated with O3 (adjusted OR 1.138, 95% confidence interval (CI) 1.001 to 1.293), CO (adjusted OR 1.045, 95% CI 1.017 to 1.074), and NOx (adjusted OR 1.005, 95% CI 0.954 to 1.117). Against our prior hypothesis, the risk of childhood asthma was weakly or not related to SO2 (adjusted OR 0.874, 95% CI 0.729 to 1.054) and PM10 (adjusted OR 0.934, 95% CI 0.909 to 0.960). CONCLUSIONS: The results are consistent with the hypothesis that long term exposure to traffic related outdoor air pollutants such as NOx, CO, and O3 increases the risk of asthma in children.

Exposure to traffic exhausts and oxidative DNA damage.

AIMS: To assess the relations between exposure to traffic exhausts and indicators of oxidative DNA damage among highway toll station workers. METHODS: Cross-sectional study of 47 female highway toll station workers exposed to traffic exhausts and 27 female office workers as a reference group. Exposure assessment was based on average and cumulative traffic density and a biomarker of exposure, urinary 1-hydroxypyrene-glucuronide (1-OHPG). Urinary 8-hydroxydeoxyguanosine (8-OHdG) was used as a biomarker of oxidative DNA damage. Plasma nitric oxide (NO) was measured as an indicator of oxidative stress related to traffic exhaust exposure. RESULTS: The mean concentration of urinary 8-OHdG was substantially higher among the exposed non-smokers (13.6 microg/g creatinine) compared with the reference non-smokers (7.3 microg/g creatinine; difference 6.3, 95% CI 3.0 to 9.6). The mean concentration of NO among the exposed (48.0 micromol/l) was also higher compared with the reference non-smokers (37.6 micromol/l; difference 10.4, 95% CI -0.4 to 21.2). In linear regression adjusting for confounding, a change in log(8-OHdG) was statistically significantly related to a unit change in log(1-OHPG) (beta = 0.372, 95% CI 0.081 to 0.663). CONCLUSIONS: Results indicate that exposure to traffic exhausts increases oxidative DNA damage. Urinary 8-OHdG is a promising biomarker of traffic exhaust induced oxidative stress.

Day care center characteristics and children's respiratory health.

UNLABELLED: Day care centers provide an important exposure arena with potential harmful health effects for children. This study has linked health effect data from a survey among 942 3-5-year-old Oslo children with information on day care center characteristics collected during inspection of the 175 day care centers these children attended. The aim of the study was to estimate associations between dampness problems and other building characteristics and several respiratory health outcomes. Dampness problems (sign of molds, water leakage, damage to floor/wall) were observed in 51% of the day care centers. In multiple logistic regression analyses none of the studied symptoms and diseases (nightly cough, blocked or runny nose without common cold, wheeze, heavy breathing or chest tightness, the common cold, tonsillitis/pharyngitis, otitis media, bronchitis, pneumonia, asthma, and allergic rhinitis) were systematically associated with dampness problems or type of ventilation in day care centers. None of the studied indicators of day care center exposures were found to have a clear effect on day care children's respiratory health. Even so this study does not rule out negative health effects of day care center exposures. The study demonstrates that population-based studies of these relations are demanding with regard to assessment of exposure and health outcomes. PRACTICAL IMPLICATIONS: Simple and easy-to-register indicators of exposures like dampness problems and type of ventilation assessed in 175 day care centers were not related to respiratory health among 3-5-year-old Norwegian children attending the day care centers. The study does not rule out negative health effects of day care center exposures, but demonstrates methodological challenges needed to be addressed in studies of health effects of the day care environment.

Smoking and asthma in adults.

Studies on the effect of smoking on adulthood asthma have provided contradictory results. The current authors conducted a population-based incident case-control study to assess the effects of current and past smoking on the development of asthma in adults. During a 2.5 yr study period, all new asthma cases clinically diagnosed (n=521) and randomly selected controls (n=932) from a geographically defined district in southern Finland were recruited. The risk of developing asthma was significantly higher among current smokers with an adjusted odds ratio (OR) of 1.33 (95% confidence interval 1.00-1.77) and among ex-smokers with an adjusted OR 1.49 (1.12-1.97) compared with never-smokers. Among current smokers, the risk increased up to 14 cigarettes x day(-1), and a similar trend was observed in relation to cumulative smoking. In conclusion, the current results support the hypothesis that smoking causes asthma in adulthood.

Significance of humidity and temperature on skin and upper airway symptoms.

The objective of the present study was to assess the effect of absolute and relative humidity, temperature and humidification on workers' skin and upper airway symptoms, and perceptions in the office environment. Associations between physical factors, and symptoms and perceptions were assessed in logistic regression models. At temperatures between 18 and 26 degrees C, relative humidity of 17-40%, and absolute humidity of 3.3-5.6 g H2O/kg air, skin symptoms and nasal dryness and congestion were alleviated by both kinds of humidity. Pharyngeal dryness increased when temperatures rose and was alleviated with a rise in relative humidity. Eye symptoms showed no dependence on humidity. Any kind of humidity increased odor sensation. Stuffiness increased when the air was humidified. In non-humidified conditions (21.3-22.7 degrees C, 20.0-31.7%, 3.3-5.6 g H2O/kg air), skin and nasal symptoms showed no association with humidity or temperature. Pharyngeal dryness diminished when humidity rose. In addition, the association between humidity and odor disappeared. In humidified conditions (21.5-23.7 degrees C, 26.6-41.2%, 4.2-7.0 g H2O/kg air), nasal dryness and congestion were alleviated by both absolute and relative humidity, and odor perception increased. Skin dryness and rash, pharyngeal dryness, and nasal dryness and congestion are alleviated in higher humidity. Steam humidification results in a risk for increased perception of odor and stuffiness.

Case-crossover design in air pollution epidemiology.

The case-crossover design was developed to study the effects of transient, short-term exposures on the risk of acute events, such as myocardial infarction, in the early 1990s. This paper illustrates how the principles of case-crossover design are related to the principles of crossover and case-control designs and stipulates the possibilities of case-crossover design in air pollution epidemiology. In the case-crossover design, the study population consists of subjects who have experienced an episode of the health outcome of interest. Similar to a crossover study, each subject serves as his or her own control. As in a matched case-control study, the inference is based on a comparison of exposure distribution rather than the risk of disease. The case-crossover study is most suitable for studying relations with the following characteristics: 1) the individual exposure varies within short time intervals; 2) the disease has abrupt onset and short latency for detection; and 3) the induction period is short. Case-crossover design allows use of routinely monitored air pollution information and at the same time makes it possible to study individuals rather than days as the unit of observation. Case-crossover design is amenable for studying the effects of varying short-term air pollution exposure on health outcomes with an abrupt onset, such as myocardial infarction or asthma attack.

Feasibility of measuring lung function in preschool children.

BACKGROUND: There have been difficulties in applying spirometric tests to children of preschool age. METHODS: The feasibility of measuring lung function was examined in 652 children aged 3-6 years using dynamic spirometry with an animation programme and the guidelines approved by the European Respiratory Society. RESULTS: Data from 603 (92%) children with at least two acceptable forced expiratory manoeuvres were analysed; 408 (68%) achieved at least three acceptable manoeuvres. Children with only two acceptable manoeuvres were younger, shorter, and weighed less (p<0.001). The lower levels of lung function in this group were partly explained by body size. 63% of those with three acceptable manoeuvres had a difference of

The use of a feather quilt, childhood asthma and allergic rhinitis: a prospective cohort study.

BACKGROUND: Feather bedding has long been considered as a potential source of allergen exposure and thus a potential risk factor for allergic diseases. However, recent cross-sectional studies have reported a higher risk of allergic diseases among users of synthetic bedding compared with feather-bedding users. OBJECTIVE: To explore associations between early life exposure to feather bedding and the risk of developing asthma allergic rhinitis in childhood. METHODS: We assessed the association between early life exposure to feather quilts and the risk of bronchial obstruction during the first 2 years of life and asthma and allergic rhinitis in a prospective 4-year cohort study of 2531 Norwegian children. RESULTS: At the age of 6 months, 24% of the children had a quilt with feathers, decreasing to 20% at the age of 2 years. The adjusted odds ratio for bronchial obstruction 0 to 2 years by exposure to a feather quilt at the age of 6 months was 0.59, 95% confidence interval 0.41 to 0.86, for asthma at the age of 4 years 0.38, 0.23 to 0.64 and for allergic rhinitis at the age of 4 years 0.73, 0.43 to 1.18. CONCLUSION: The use of a feather quilt in early life does not seem to increase the risk of asthma and allergic rhinitis later in childhood.

Immunoglobulin G antibodies against indoor dampness-related microbes and adult-onset asthma: a population-based incident case-control study.

Immunoglobulin G (IgG) antibodies against microbes related to indoor dampness problems have been used as potential biomarkers of fungal exposure in clinical investigations. There is limited information on their relation to asthma. We conducted a population-based incident case-control study to assess the risk of asthma in relation to specific IgG antibodies to eight dampness-related microbes: Aspergillus fumigatus, A. versicolor, Cladosporium cladosporioides, Fusarium oxysporum, Sporobolomyces salmonicolor, Stachybotrys chartarum, Streptomyces albus and Trichoderma citrinoviride. We recruited systematically all new cases of asthma during a 2.5-year study period and randomly selected controls from a source population of adults 21-63 years of age living in the Pirkanmaa Hospital District, South Finland. The clinically diagnosed case series consisted of 521 adults with newly diagnosed asthma and the control series of 932 controls selected randomly from the source population. IgG antibodies were analysed with ELISA. An increased risk of developing asthma in adulthood was significantly related to IgG antibodies to T. citrinoviride, but not to the other moulds. There was no evidence of a dose-response relation between the IgG antibody level and the risk of asthma. T. citrinoviride may play a role in the aetiology of adult-onset asthma or serve as an indicator of other causal factors.