Prenatal risk factors of indoor environment and incidence of childhood eczema in the Japan Environment and Children's Study.

The quality of indoor environment is a risk factor for early childhood eczema and atopic dermatitis; however, its influence during pregnancy on childhood eczema in Japan has not been investigated. In this study, we aimed to determine the indoor environmental factors that are associated with eczema in children up to 3 years of age, using national birth cohort data from the Japan Environment and Children's Study (JECS). Information on indoor environments and eczema symptoms until 3 years of age was collected using self-administered questionnaires to the mothers. A total of 71,883 and 58,639 mother-child pairs at 1.5- and 3-years-old, respectively, were included in the former analyses. To account for prenatal indoor risk factors, 17,568 (1.5-years-old) and 7063 (3-years-old) children without indoor mold and/or ETS exposure were included in the final analysis. A higher mold index, gas heater use, parquet flooring use, and frequent insecticide use showed significantly increased risks for childhood eczema up to 3 years of age. These associations were consistent after stratification analysis among children whose parents did not have a history of allergies. The updated WHO guidelines on indoor air quality should be implemented based on recent findings regarding the effects of prenatal exposure to indoor dampness on health effects of children further in life, including asthma, respiratory effects, eczema, and other immunological effects.

Teenage and young adult pregnancy and depression: findings from the Japan environment and children's study.

Teenage pregnancy increases the threat of depression because of its many factors. Pregnancy during young adulthood may also have several risk factors for depression compared to older pregnancies. However, data on depression in young adult pregnancies are lacking. This study investigated the association between teenage and young adult pregnancy and depression. Data from the Japan Environment and Children's study was used as a nationwide multicenter prospective cohort study. A multivariate logistic regression was performed to investigate the association between age groups (14-19, 20-24, 25-29, 30-34, ≥ 35 years) and depression, adjusted for behavioral and sociodemographic characteristics. Depression was assessed using the Kessler Psychological Distress Scale. In total, 96,808 pregnant women responded to the questionnaire. Teenage (14-19 years) and young adult (20-24 years) pregnancy were associated with an increased risk of depression compared to older pregnancy (≥ 35 years) (teenage: OR 4.28, 95% confidence interval, CI [3.24-5.64]; young adult: OR 3.00, 95% CI [2.64-3.41]). After adjusting for covariates, the magnitude of the risk of depression was attenuated. However, teenage and young adult pregnancy remained at a significantly increased risk of depression compared to older pregnancy (teenage: OR 2.38, 95% CI [1.77-3.21]; young adult: OR 2.14, 95% CI [1.87-2.46]). Our findings indicate that teenage and young adults' pregnancy are at an increased risk of depression compared to older pregnancy. These findings suggest prioritizing teenage and young pregnant women for prevention and interventions related to depression.

Association between general anesthesia in early childhood and neurodevelopment up to 4 years of age: the Japan Environment and Children's Study.

PURPOSE: The effects of general anesthesia on neurodevelopment in children remain controversial. We explored the relationship between general anesthesia and neurodevelopment in children participating in the Japan Environment and Children's Study (JECS). METHODS: This study enrolled children born between 37 and 41 weeks of pregnancy via single-vaginal delivery to pregnant women registered in the JECS between January 2011 and March 2014. Data were collected from mother-completed questionnaires and medical transcripts. Neurodevelopment in five domains was assessed every 6 months between 12 and 48 months of age, using the Ages and Stages Questionnaires. The associations between general anesthesia exposure during early childhood and neurodevelopment in children were evaluated at each time point. Adjusted odds ratios and 95% confidence intervals were estimated after covariate adjustment using logistic regression models. RESULTS: Children who received general anesthesia before age 1 year had higher risks of neurodevelopmental delay in all five domains throughout the observational period. The largest risk was for gross motor delay at 18 months (adjusted odds ratio: 3.51; 95% confidence interval: 2.75-4.49). The effects on the incidence of neurodevelopmental delays after age 3 were not observed except for problem solving at 48 months. The risk of neurodevelopmental delay in children who first received general anesthesia after age 1 was considerably small. CONCLUSIONS: This study suggests that general anesthesia administration before age 1 is associated with neurodevelopmental delay during 1-4 years of age. The risk of general anesthesia after age 1 may be small.

Exposure to ambient fine particulate matter components during pregnancy and early childhood and its association with asthma, allergies, and sensitization in school-age children.

BACKGROUND: Exposure to fine particulate matter (PM2.5) has been associated with allergic diseases, including asthma. However, information about the effects of specific PM2.5 components is limited. This study aimed to investigate the relationship of exposure to chemical components of PM2.5 during pregnancy and early childhood with the development of asthma, allergies, and sensitization in school-age children. METHODS: This study included 2,408 children in the second grade of elementary school. Questionnaire surveys of respiratory/allergic symptoms and measurements of serum total IgE and specific IgE levels to house dust mite (HDM) and animal proteins were conducted. Exposures to ambient PM2.5 mass, sulfate (SO42-), nitrate (NO3-), ammonium (NH4+), elemental carbon (EC), and organic carbon (OC) of PM2.5 in participants' residences from conception to age six were estimated using predictive models. Multiple logistic regression analysis was used to analyze the association of respiratory/allergic symptoms and allergen sensitization with estimated exposure concentrations, after adjustment for survey year, sex, season of birth, feeding method during infancy, presence of siblings, history of lower respiratory tract infection, use of childcare facilities, passive smoking, presence of pets, mother's age, history of allergic diseases, smoking during pregnancy, and annual household income. RESULTS: No significant association was found between PM2.5 and its component concentrations and asthma. However, wheezing significantly increased with mean NO3- concentrations during pregnancy (odds ratio of 1.64 [95% confidence interval: 1.10, 2.47] for an interquartile range increase). Significant associations were also found between EC in the second trimester of pregnancy and PM2.5, NO3-, EC, and OC concentrations in early childhood. Higher PM2.5, SO4-, and NH4+ concentrations during the second trimester increased the risk of rhinitis. Sensitizations to HDM and animal proteins were significantly associated with exposure to components such as SO42- and NH4+ during pregnancy but not with postnatal exposure. CONCLUSIONS: Exposures to NO3-, EC, and OC during pregnancy and early childhood were associated with wheezing. SO42- and NH4+ exposures during pregnancy were associated with sensitization to HDM and animal proteins. Asthma was not associated with exposure to PM2.5 and its main components at any period.

Association of mesothelioma deaths with neighborhood asbestos exposure due to a large-scale asbestos-cement plant.

A causal relationship between mesothelioma and occupational asbestos exposure is well known, while some studies have shown a relationship to non-occupational exposures. The aim of this study was to quantify the risk of mesothelioma death associated with neighborhood asbestos exposure due to a large-scale asbestos-cement (AC) plant in Amagasaki, Japan, adjusting properly risk factors including occupational exposures. We conducted a nested case-control study in which a fixed population of 143,929 residents who had been living in Amagasaki City between 1975 and 2002 were followed from 2002 to 2015. All 133 cases and 403 matched controls were interviewed about their occupational, domestic, household, and neighborhood asbestos exposures. Odds ratios (ORs) for mesothelioma death associated with the neighborhood exposure were estimated by a conditional logistic-regression model. For quantitative assessments for neighborhood exposure, we adopted cumulative indices for individuals' residential histories at each residence-specific asbestos concentration multiplied by the duration during the potential exposure period of 1957-1975 (crocidolite). We observed an increasing, dose-dependent risk of mesothelioma death associated with neighborhood exposure, demonstrating that ORs in the highest quintile category were 21.4 (95% confidence interval [CI] 5.8-79.2) for all, 23.7 (95% CI 3.8-147.2) for males, and 26.0 (95% CI 2.8-237.5) for females compared to the lowest quintile, respectively. A quantitative assessment for risk of mesothelioma deaths, adjusting for occupational and non-occupational exposures separately, showed a dose-dependent association with neighborhood exposure and no substantial gender differences in magnitude.

Association of air pollution exposure during pregnancy and early childhood with children's cognitive performance and behavior at age six.

BACKGROUND: The impact of air pollution on neurodevelopment in children has attracted much attention in recent times. We aim to clarify the association between prenatal and postnatal air pollutant exposure and children's cognitive performance and behavior at age six. METHODS: This study was conducted based on a birth cohort study in Japan. Children's intelligence quotient (IQ) was assessed using the Wechsler Intelligence Scale for Children and a score <85 was deemed as low intelligence. A score ≥60 on the Child Behavior Checklist indicated behavioral problems. Exposure to outdoor fine particulate matter (PM2.5) during pregnancy and early childhood was estimated using a spatiotemporal model, while indoor concentrations of air pollutants inside subjects' homes were measured for a week when the child was of ages 1.5 and 3. The associations of exposure to air pollution during pregnancy and after childbirth with cognitive performance and behavior were analyzed using logistic regression models. RESULTS: The estimated exposure to outdoor PM2.5 during pregnancy and early childhood was not associated with decreased cognitive performance. However, exposure during the first trimester, 0-1 and 3-5 years of age was associated with children's externalizing problems (odds ratios (ORs) were 2.77 [95% confidence interval (CI): 1.05-7.29], 1.66 [95%CI: 1.05-2.62], and 1.80 [95%CI: 1.19-2.74] per interquartile range (IQR) increase, respectively). Exposure to indoor PM2.5 and coarse particles after childbirth was associated with lower full scale IQ (ORs were 1.46 [95%CI: 1.03-2.08] and 1.85 [95%CI: 1.12-3.07] per IQR increase, respectively). However, some inverse associations were also observed. CONCLUSIONS: These results suggest associations between prenatal and postnatal exposure to outdoor air pollution and behavioral problems, and between indoor air pollution after childbirth and cognitive performance at age six. However, the effects of exposure to outdoor PM2.5 during pregnancy on cognitive performance were not observed.

Association between maternal use of spray formulations and offspring urological anomalies: The Japan Environment and Children's Study.

OBJECTIVE: Concerns exist regarding the effects of maternal inhalation of household products on fetal health. This study aimed to clarify the impact of maternal exposure to household products, including spray formulations, on urological anomalies in offspring up to the age of 1 year. METHODS: This study included data from 84 237 children from the Japan Environment and Children's Study, an ongoing nationwide cohort study. Using maternal self-report questionnaires, information on the use of organic solvents, waterproof sprays, insect-repellent sprays, insecticide sprays, and herbicides from implantation until the second or third trimester of pregnancy and data on urological anomalies were collected 1 year after delivery. RESULTS: Urological anomalies occurred in 799 infants. Multivariate logistic regression analysis adjusted for maternal age, pregnancy body mass index, gestational diabetes, pre-existing maternal kidney disease, and preterm birth revealed no association between maternal exposure to organic solvents and the prevalence of offspring urological anomalies. Nevertheless, we observed significant associations between waterproof spray use during pregnancy and urological anomalies in boys (odds ratio [OR]: 1.28, 95% confidence interval [CI]: 1.03-1.59) and between the use of insecticide spray during pregnancy and urological anomalies in girls (OR: 1.48, 95% CI: 0.98-2.22). Sub-analysis revealed significant associations between waterproof spray use during pregnancy and vesicoureteral reflux in boys (OR: 2.14, 95% CI: 1.02-4.49) and between the use of insecticide spray during pregnancy and hydronephrosis in girls (OR: 2.23, 95% CI: 1.11-4.47). CONCLUSION: Spray formulation use during pregnancy might increase the risk of urological anomalies in the offspring.

Relations of mold, stove, and fragrance products on childhood wheezing and asthma: A prospective cohort study from the Japan Environment and Children's Study.

This prospective cohort study aimed to examine the associations between mold growth, type of stoves, and fragrance materials and early childhood wheezing and asthma, using data from the Japan Environment and Children's Study. Mold growth at home, usage of kerosene/gas stove, wood stove/fireplace, and air freshener/deodorizer were surveyed using a questionnaire at 1.5-year-old, and childhood wheezing and doctor-diagnosed asthma during the previous year were obtained using a 3-year-old questionnaire. Multilevel logistic regression analysis was performed to evaluate the association between exposure to childhood wheezing and asthma. A total of 60 529 children were included in the analysis. In multivariate analyses, mold growth and wood stove/fireplace had significantly higher odds ratios (ORs) for wheezing (mold growth: 1.13; 95% CI, 1.06-1.22; wood stove/fireplace: 1.23; 95% CI, 1.03-1.46). All four exposures had no significant ORs for childhood doctor-diagnosed asthma; however, in the supplemental analysis of northern regions, wood stove/fireplace had a significantly higher OR for asthma. Mold growth and wood stove/fireplace had significant associations with childhood wheezing in the northern regions. Mold elimination in the dwellings and use of clean heating (no air pollution emissions) should be taken into consideration to prevent and improve childhood wheezing and asthma.

Association of epidural analgesia during labor with neurodevelopment of children during the first three years: the Japan Environment and Children's Study.

BACKGROUND: Epidural analgesia relives pain during labor. However, the long-term effects on neurodevelopment in children remain unclear. We explored associations between exposure to epidural analgesia during labor and childhood neurodevelopment during the first 3 years of life, in the Japan Environment and Children's Study (JECS), a large-scale birth cohort study. METHODS: Pregnant women were recruited between January 2011 and March 2014, and 100,304 live births of singleton children born at full-term by vaginal delivery, and without congenital diseases were analyzed. Data on mothers and children were collected using a self-administered questionnaires and medical record transcripts. The children's neurodevelopment was repeatedly assessed for five domains (communication, gross motor, fine motor, problem solving, and personal-social), using the Ages and Stages Questionnaires, Third Edition, at six time points from age 6 to 36 months. After adjusting for potential confounders, the associations between exposure to epidural analgesia during labor and children's neurodevelopment at each time point were assessed. RESULTS: Of the 42,172 children with valid data at all six time points, 938 (2.4%) were born to mothers who received epidural analgesia during labor. Maternal exposure to epidural analgesia was associated with neurodevelopmental delays during the first 3 years after birth. Delay risks in gross and fine motor domains were the greatest at 18 months (adjusted odds ratio (aOR) [95% confidence interval (CI)]: 1.40 [1.06, 1.84] and 1.54 [1.17, 2.03], respectively), subsequently decreasing. Delay risks in communication and problem-solving domains were significantly high at 6 and 24 months, and remained significant at 36 months (aOR [95% CI]: 1.40 [1.04, 1.90] and 1.28 [1.01, 1.61], respectively). Exposure to epidural analgesia was also associated with the incidence of problem solving and personal-social delays from 18 to 24 months old. Neurodevelopmental delay risks, except for communication, were dominant in children born to mothers aged ≥30 years at delivery. CONCLUSIONS: This study showed that maternal exposure to epidural analgesia during labor was associated with neurodevelopmental delays in children during the first 3 years after birth.

Association between the serum insulin-like growth factor-1 concentration in the first trimester of pregnancy and postpartum depression.

AIM: Patients with major depression present with an increased serum insulin-like growth factor-1 (IGF-1) concentration. However, the longitudinal relationship between serum IGF-1 levels and depression development remains unclear. This study aimed to investigate the longitudinal association between the serum IGF-1 concentration in the first trimester of pregnancy and postpartum depression development using data obtained from the Japan Environment and Children's Study (JECS). METHODS: The JECS included 97 415 pregnant women; among them, 8791 were enrolled in this study. Data regarding depression in the first trimester, postpartum depression development at 1 month after childbirth, and other covariates were collected using a self-administered questionnaire. Serum IGF-1 levels were measured in the first trimester of pregnancy. The participants were divided into four groups according to the serum IGF-1 level. RESULTS: In the first trimester, serum IGF-1 levels were not significantly associated with psychological distress in pregnant women. In the longitudinal analyses, however, postpartum depression development in mothers within the highest quartile for serum IGF-1 concentration in the first trimester was significantly less common than in those within the lowest quartile (odds ratio 0.48, 95% confidence interval 0.30-0.79). CONCLUSION: Pregnant women with a high serum IGF-1 concentration in the first trimester were less likely to develop postpartum depression than those with a low concentration. A high serum IGF-1 concentration during pregnancy may help to protect against postpartum depression development.

Association between house renovation during pregnancy and wheezing in the first year of life: The Japan environment and children's study.

BACKGROUND: Wheezing is a common symptom in infants, which may occasionally develop into asthma. There are many factors related to infant wheezing, including anatomical features, viral infections, and passive smoking. There are only a few reports on the association between renovation and pregnancy worldwide, and reports on this association are inadequate in Japan. This study aimed to examine the association between house renovation and new construction during pregnancy and wheezing in infants during the first year of life using data from the Japan Environment and Children's Study (JECS). METHODS: Data of pregnant women registered in JECS were collected using self-administered questionnaires during the second/third trimester and 1 month after delivery. Childbirth records were completed by the doctors. Similarly, wheezing in infants was evaluated using self-administered questionnaires 1 year after birth. Logistic regression analysis was used to determine the primary outcome. RESULTS: In total, 75,731 infants, excluding those with unknown gender, who were not singleton infants, and who relocated during pregnancy and the first month of life, were examined in this study. Renovation during pregnancy increased the prevalence of wheezing (odds ratio [OR]: 1.33, 95% confidence interval [CI]: 1.20-1.48) and recurrent wheezing (OR: 1.22, 95% CI: 1.00-1.48) in the first year of life. The relationship between new construction during pregnancy and wheezing in infants was insignificant (OR: 0.98, 95% CI: 0.90-1.06). CONCLUSIONS: Renovation during pregnancy may be a risk factor for wheezing in infants, and should be avoided.

Association of Protein and Endotoxin in Outdoor Air with Emergency Department Visits for Children and Adults with Asthma in Fukuoka, Japan.

We examined the association of biological components in airborne particles, i.e., proteins and endotoxins, in outdoor air with asthma exacerbation in the Fukuoka metropolitan area, Fukuoka, Japan. Data on emergency department (ED) visits for asthma in children (age, 0-14 years) and adults (age, 15-64 years) were collected at a medical center from December 2014 to November 2015. One hundred eighty-one children and 143 adults visited the ED for asthma, and the weekly number of ED visits in children increased in autumn, i.e., September (second week) to November (first week). Fine (aerodynamic diameter ≤2.5 µm) and coarse (≥2.5 µm) particles were collected for 3 or 4 weeks per month, and protein and endotoxin concentrations were analyzed. Protein was largely prevalent in fine particles (0.34-7.33 µg/m3), and concentrations were high in April, May, June, and October. In contrast, endotoxin was mainly included in coarse particles (0.0010-0.0246 EU/m3), and concentrations were high in September (third week), October (first, second, and fourth weeks), February (fourth week), and July (first week). The results of a Poisson regression analysis indicated that endotoxin (in fine and coarse particles alike) was a significant factor for ED visits related to asthma in children, even after adjusting for meteorological factors, i.e., temperature, relative humidity, and wind speed. However, there was no association between environmental factors and ED visits for asthma in adults. These results suggest that endotoxin in outdoor air is significantly associated with an increased risk of asthma exacerbation in children.

Sensitivity and specificity of different antibody tests for detecting varicella-zoster virus.

INTRODUCTION: Antibody tests for detecting varicella-zoster virus include the fluorescent-antibody-to-membrane-antigen (FAMA) assay, immune adherence hemagglutination assay (IAHA), enzyme immunoassay (EIA), and the glycoprotein-based enzyme-linked immunosorbent assay (gpELISA). Although FAMA and gpELISA are highly sensitive, FAMA is not available commercially. Therefore, this study was performed to compare potential high-sensitivity tests with commercially available tests. METHODS: Four antibody tests, FAMA, gpELISA, EIA, and IAHA, were performed using sera collected from 32 children aged 7 months-10 years. Using FAMA as a reference, the sensitivity and specificity of gpELISA, EIA, and IAHA were assessed. Subsequently, using gpELISA as a reference, the positive agreement rate of EIA and IAHA was assessed. RESULTS: On a reference scale with FAMA set at 100%, the sensitivity and specificity of the antibody tests were as follows: gpELISA, 67% and 100%; EIA, 67% and 100%; and IAHA, 47% and 100%, respectively. The positive agreement rates of EIA and IAHA relative to gpELISA were 86% and 64%, respectively. CONCLUSIONS: gpELISA had a lower positive rate than did FAMA, and showed comparable sensitivity to that of EIA.

Association between surgical procedures under general anesthesia in infancy and developmental outcomes at 1 year: the Japan Environment and Children's Study.

BACKGROUND: The neurotoxicity of general anesthesia to the developing human brains is controversial. We assessed the associations between surgery under general anesthesia in infancy and development at age 1 year using the Japan Environment and Children's Study (JECS), a large-scale birth cohort study. METHODS: In the JECS, 103,062 pregnancies and 104,065 fetuses were enrolled between January 2011 and March 2014. Of the 100,144 registered live births, we excluded preterm or post-term infants, multiple births, and infants with chromosomal anomalies and/or anomalies of the head or brain. Data on surgical procedures under general anesthesia in infancy were collected from self-administered questionnaires by parents at the 1-year follow-up. Developmental delay at age 1 year was assessed using the Japanese translation of the Ages and Stages Questionnaires, Third Edition (J-ASQ-3), comprising five developmental domains. RESULTS: Among the 64,141 infants included, 746 infants had surgery under general anesthesia once, 90 twice, and 71 three or more times. The percentage of developmental delay in the five domains of the J-ASQ-3 significantly increased with the number of surgical procedures. After adjusting for potential confounding factors, the risk of developmental delays in all five domains was significantly increased in infants who had surgery under general anesthesia three times or more (adjusted odds ratios: for communication domain 3.32; gross motor domain 4.69; fine motor domain 2.99; problem solving domain 2.47; personal-social domain 2.55). CONCLUSIONS: Surgery under general anesthesia in infancy was associated with an increased likelihood of developmental delay in all five domains of the J-ASQ-3, especially the gross motor domain at age 1 year. The neurodevelopment with the growth should be further evaluated among the children who had surgery under general anesthesia. TRIAL REGISTRATION: UMIN Clinical Trials Registry (number: UMIN000030786 ).

Population-based cohort study on health effects of asbestos exposure in Japan.

Occupational asbestos exposure occurs in many workplaces and is a well-known cause of mesothelioma and lung cancer. However, the association between nonoccupational asbestos exposure and those diseases is not clearly described. The aim of this study was to investigate cause-specific mortality among the residents of Amagasaki, a city in Japan with many asbestos factories, and evaluate the potential excess mortality due to established and suspected asbestos-related diseases. The study population consisted of 143 929 residents in Amagasaki City before 1975 until 2002, aged 40 years or older on January 1, 2002. Follow-up was carried out from 2002 to 2015. Standardized mortality ratio (SMR) with its 95% confidence interval (CI) was calculated by sex, using the mortality rate of the Japanese population as reference. A total of 38 546 deaths (including 303 from mesothelioma and 2683 from lung cancer) were observed. The SMRs in the long-term residents' cohort were as follows: death due to all causes, 1.12 (95% CI, 1.10-1.13) in men and 1.07 (95% CI, 1.06-1.09) in women; lung cancer, 1.28 (95% CI, 1.23-1.34) in men and 1.23 (95% CI, 1.14-1.32) in women; and mesothelioma, 6.75 (95% CI, 5.83-7.78) in men and 14.99 (95% CI, 12.34-18.06) in women. These SMRs were significantly higher than expected. The increased SMR of mesothelioma suggests the impact of occupational asbestos exposure among men and nonoccupational asbestos exposure among women in the long-term residents' cohort. In addition, the high level of excess mortality from mesothelioma has persisted, despite the mixture of crocidolite and chrysotile no longer being used for three or four decades.

Evaluation of influenza vaccine-induced cell-mediated immunity: Comparison between methods using peripheral blood mononuclear cells and whole blood.

Assessment of cell-mediated immunity (CMI) may be critical to evaluating the ability of individuals to protect themselves against influenza virus infection. However, it has been difficult to evaluate CMI because no simple means of measuring it is currently available. The aim of this study was to compare the performance of a CMI measurement method developed by us, which involves reacting whole blood with antigen, with the conventional method, which is based on isolating peripheral blood mononuclear cells (PBMCs). Correlations between these methods before and after vaccination of 26 healthy adults (aged 28-58 years; 12 men and 14 women) were assessed and changes in CMI after influenza vaccination in PBMCs cultured with antigen for 48 and 96 hr and whole blood cultured with antigen for 48 hr were studied. Results of CMI measurement using whole blood on Day 2 and PBMCs on Day 4 were found to be correlated. Spearman's correlation coefficients with four antigens (A [H1N1], A [H3N2], B [Yamagata lineage], and B [Victoria lineage]) before vaccination were 0.55, 0.61, 0.58, and 0.70, respectively and 0.40, 0.45, 0.62, and 0.52, respectively, after vaccination. CMI was detected sooner when whole blood was reacted with antigen than when PBMCs were reacted with antigen. The rate of positive reaction of influenza A (H1N1 and H3N2) in whole blood on Day 2 was higher than that in PBMCs on Day 2. Our method is simple and may be useful for vaccine development because it can measure CMI in a small amount of blood without separating off PBMCs.

Association between chemical components of PM2.5 and children's primary care night-time visits due to asthma attacks: A case-crossover study.

BACKGROUND: Few papers have examined the association between the chemical components of PM2.5 and health effects. The existence of an association is now under discussion. METHODS: This case-crossover study aimed to examine the association between the chemical components of PM2.5 and night-time primary care visits (PCVs) due to asthma attacks. The subjects were 1251 children aged 0-14 years who received medical care for asthma at a municipal emergency clinic. We measured daily average concentrations of hydrogen ion, sulfate ion, nitrate ion and water-soluble organic compounds (WSOCs), which are components of PM2.5. We estimated the odds ratios (ORs) of PCVs per unit increment (inter quartile ranges) in each chemical component of PM2.5 for the subgroups of warmer months and colder months separately. RESULTS: No association was seen between PCVs and PM2.5 mass concentrations the day before the PCVs in either warmer or colder months. In the warmer months, an association was seen with the concentrations of WSOCs and hydrogen ion the day before the PCVs (OR = 1.33; 95% CI: 1.00-1.76, OR = 1.18; 95% CI: 1.02-1.36, respectively). Furthermore, a negative association was seen between sulfate ion and PCVs (OR = 0.85; 95%CI: 0.74-0.98). No associations were observed in the colder months. CONCLUSIONS: We observed a positive association between PCVs and certain concentrations of WSOCs and hydrogen ions in warmer months. In contrast, sulfate ion showed a negative association.

Dioxins levels in human blood after implementation of measures against dioxin exposure in Japan.

BACKGROUND: Over the past few decades, the Japanese Ministry of the Environment has been biomonitoring dioxins in the general Japanese population and, in response to public concerns, has taken measures to reduce dioxin exposure. The objectives of this study were to assess the current dioxin dietary intake and corresponding body burden in the Japanese and compare Japanese dioxin data from 2011 to 2016 and 2002-2010 surveys. We also examined the relationship between blood dioxins and health parameters/clinical biomarkers. METHODS: From 2011 to 2016, cross-sectional dioxin surveys were conducted on 490 Japanese (242 males and 248 females, aged 49.9 ± 7.6 years) from 15 Japanese prefectures. Blood (n = 490) and food samples (n = 90) were measured for 29 dioxin congeners including polychlorinated dibenzo-para-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (Co-PCBs) using gas chromatography coupled with high-resolution mass spectrometry. Using the 2006 World Health Organization toxic equivalence factors, the toxic equivalents (TEQs) were calculated. Clinical biomarkers and anthropometric parameters were also measured and information on lifestyle behaviours collected. Data imputations were applied to account for blood dioxins below the detection limit. RESULTS: The median (95% confidence interval or CI) blood levels and dioxin dietary intake was respectively 9.4 (8.8-9.9) pg TEQ/g lipid and 0.3 (0.2-0.4) pg TEQ/kg body weight/day. The median blood dioxin level in the 2011-2016 survey was found to have decreased by 41.3% compared to the 2002-2010 surveys. Participants who were older were found to be more likely to have higher dioxin levels. Blood dioxins were also significantly associated with body mass index, triglycerides, docosahexaenoic acid, eicosapentaenoic acid, and dihomo-gamma-linoleic acid levels in blood. Furthermore, associations between blood dioxin and dietary dioxin intake were evident in the unadjusted models. However, after adjusting for confounders, blood dioxins were not found to be associated with dietary dioxin intake. CONCLUSIONS: Blood dioxin levels declined over the past decade. This study showed that the measures and actions undertaken in Japan have possibly contributed to these reductions in the body burden of dioxins in the Japanese population.

Coal burning-derived SO2 and traffic-derived NO2 are associated with persistent cough and current wheezing symptoms among schoolchildren in Ulaanbaatar, Mongolia.

BACKGROUND: Children in Ulaanbaatar are exposed to air pollution, but few epidemiological studies have been conducted on the effects of environmental risk factors on children's health. Also, no studies have yet examined the prevalence of respiratory symptoms in children in suburban areas, where air quality-monitoring stations have not yet been installed. This cross-sectional study evaluated the associations between outdoor air pollution and respiratory symptoms among schoolchildren in urban and suburban districts of Ulaanbaatar. METHODS: The ATS-DLD-78 C questionnaire was used to investigate the respiratory symptoms of schoolchildren aged 6-12 years (n = 1190) who lived in one of three urban districts or a suburban district of Ulaanbaatar. In each district, the outdoor concentrations of nitrogen dioxide (NO2) and sulfur dioxide (SO2) were measured at two sites (at ≤100 m and > 100 m from the nearest major road) in the 2-year period from 2015 to 2016. The associations between health outcomes and exposure to air pollutants were estimated using the multinomial logistic regression method. RESULTS: The outdoor concentration of SO2 was significantly associated with persistent cough symptom (OR = 1.12, 95% CI 1.04-1.22). Furthermore, the outdoor concentration of NO2 was significantly associated with the current wheezing symptom (OR = 1.33, 95% CI 1.01-1.75) among children in urban and suburban. CONCLUSIONS: The prevalence of persistent cough symptom was markedly high among the schoolchildren in urban/suburban districts of Ulaanbaatar. Overall, the increases in the prevalence of respiratory symptoms among children might be associated with ambient air pollution in Ulaanbaatar.