Ambient temperature exposure and rapid infant weight gain.

BACKGROUND: Childhood obesity is a major public health concern, and the global rate is rising. Rapid infant weight gain is a risk factor for later overweight. Studies have linked prenatal ambient temperature exposure to fetal growth, and preliminary evidence suggests postnatal exposure may be associated with infant weight gain. METHODS: Using a population-based historical cohort study including 1 100 576 infants born 2011-2019, we assessed the relationship between prenatal and one-month postnatal ambient temperature exposure and rapid infant weight gain. We used a hybrid spatiotemporal model to assess temperatures at the family's recorded residence at birth. Repeated weight measurements between birth and 15 months were used to model the outcome using the SuperImposition by Translation and Rotation (SITAR) method. We employed generalized linear models and distributed lag models to estimate the association between prenatal and postnatal exposure and rapid infant weight gain, defined as the upper tertile of the SITAR growth velocity. RESULTS: Overall, higher ambient temperatures were associated with rapid infant weight gain. The cumulative adjusted relative risk for the highest exposure quintile during pregnancy compared with the lowest quintile was 1.33 [95% confidence interval (CI): 1.25, 1.40], and the corresponding association for the first postnatal month was 1.19 (95% CI: 1.15, 1.23). Exposure to high ambient temperature during early and mid-pregnancy, as well as the first postnatal month, was associated with rapid weight gain, while during late pregnancy, exposure to low temperatures was associated with this outcome. CONCLUSIONS: Prenatal and postnatal ambient temperatures are associated with rapid infant weight gain.

Active Lifestyle and Mobility of Adults with Vision Impairment: A Multiphase Mixed-Methods Study.

Individuals with vision impairment (VI) are less physically active than their sighted peers, heightening their risk of chronic illness. This study aimed to explore real and perceived barriers and promoters of an active lifestyle among adults with VI. We used mixed-methods, including a quantitative analysis of spatial data and a qualitative analysis of input from focus groups. The data were analyzed using descriptive statistics, graphical and thematic analysis. The spatial analysis highlighted frequent impediments, including high proportions of inaccessible crosswalks and stairs, a high density of obstacles (12/km) and almost inexistent guidance markings (0.1/km). Factors influencing active lifestyle of individuals with VI reported in the focus groups included: VI severity and self-confidence; accessibility of the physical environment as well as support and consideration of the society; use of behavioral strategies, striving for good health and willpower. Combined psychosocial, behavioral and infrastructural modifications could enhance active lifestyles among adults with VI. Consideration of the needs of individuals with VI is critical among environmental planners. Sustainable solutions for improving accessibility and mobility in the city for individuals with VI will influence not only their social integration but will enable them to adopt an active lifestyle and reduce their risk of chronic illness.

Joint effect of heat and air pollution on mortality in 620 cities of 36 countries.

BACKGROUND: The epidemiological evidence on the interaction between heat and ambient air pollution on mortality is still inconsistent. OBJECTIVES: To investigate the interaction between heat and ambient air pollution on daily mortality in a large dataset of 620 cities from 36 countries. METHODS: We used daily data on all-cause mortality, air temperature, particulate matter ≤ 10 µm (PM10), PM ≤ 2.5 µm (PM2.5), nitrogen dioxide (NO2), and ozone (O3) from 620 cities in 36 countries in the period 1995-2020. We restricted the analysis to the six consecutive warmest months in each city. City-specific data were analysed with over-dispersed Poisson regression models, followed by a multilevel random-effects meta-analysis. The joint association between air temperature and air pollutants was modelled with product terms between non-linear functions for air temperature and linear functions for air pollutants. RESULTS: We analyzed 22,630,598 deaths. An increase in mean temperature from the 75th to the 99th percentile of city-specific distributions was associated with an average 8.9 % (95 % confidence interval: 7.1 %, 10.7 %) mortality increment, ranging between 5.3 % (3.8 %, 6.9 %) and 12.8 % (8.7 %, 17.0 %), when daily PM10 was equal to 10 or 90 µg/m3, respectively. Corresponding estimates when daily O3 concentrations were 40 or 160 µg/m3 were 2.9 % (1.1 %, 4.7 %) and 12.5 % (6.9 %, 18.5 %), respectively. Similarly, a 10 µg/m3 increment in PM10 was associated with a 0.54 % (0.10 %, 0.98 %) and 1.21 % (0.69 %, 1.72 %) increase in mortality when daily air temperature was set to the 1st and 99th city-specific percentiles, respectively. Corresponding mortality estimate for O3 across these temperature percentiles were 0.00 % (-0.44 %, 0.44 %) and 0.53 % (0.38 %, 0.68 %). Similar effect modification results, although slightly weaker, were found for PM2.5 and NO2. CONCLUSIONS: Suggestive evidence of effect modification between air temperature and air pollutants on mortality during the warm period was found in a global dataset of 620 cities.

Interactive effects of ambient fine particulate matter and ozone on daily mortality in 372 cities: two stage time series analysis.

OBJECTIVE: To investigate potential interactive effects of fine particulate matter (PM2.5) and ozone (O3) on daily mortality at global level. DESIGN: Two stage time series analysis. SETTING: 372 cities across 19 countries and regions. POPULATION: Daily counts of deaths from all causes, cardiovascular disease, and respiratory disease. MAIN OUTCOME MEASURE: Daily mortality data during 1994-2020. Stratified analyses by co-pollutant exposures and synergy index (>1 denotes the combined effect of pollutants is greater than individual effects) were applied to explore the interaction between PM2.5 and O3 in association with mortality. RESULTS: During the study period across the 372 cities, 19.3 million deaths were attributable to all causes, 5.3 million to cardiovascular disease, and 1.9 million to respiratory disease. The risk of total mortality for a 10 µg/m3 increment in PM2.5 (lag 0-1 days) ranged from 0.47% (95% confidence interval 0.26% to 0.67%) to 1.25% (1.02% to 1.48%) from the lowest to highest fourths of O3 concentration; and for a 10 µg/m3 increase in O3 ranged from 0.04% (-0.09% to 0.16%) to 0.29% (0.18% to 0.39%) from the lowest to highest fourths of PM2.5 concentration, with significant differences between strata (P for interaction <0.001). A significant synergistic interaction was also identified between PM2.5 and O3 for total mortality, with a synergy index of 1.93 (95% confidence interval 1.47 to 3.34). Subgroup analyses showed that interactions between PM2.5 and O3 on all three mortality endpoints were more prominent in high latitude regions and during cold seasons. CONCLUSION: The findings of this study suggest a synergistic effect of PM2.5 and O3 on total, cardiovascular, and respiratory mortality, indicating the benefit of coordinated control strategies for both pollutants.

Ambient temperature and preeclampsia: A historical cohort study.

Previous studies found inconsistent associations between ambient temperature during pregnancy and the risk of preeclampsia. If such associations are causal, they may impact the future burden of preeclampsia in the context of climate change. We used a historical cohort of 129,009 pregnancies (5074 preeclampsia cases) from southern Israel that was merged with temperature assessments from a hybrid satellite-based exposure model. Distributed-lag and cause-specific hazard models were employed to study time to all preeclampsia cases, followed by stratification according to early (≤34 weeks) and late (>34 weeks) onset disease and identify critical exposure periods. We found a positive association between temperature and preeclampsia during gestation, which was stronger in the 3rd trimester. For example, during week 33, compared to the reference temperature of 22.4 °C, the cause-specific hazard ratio (HRCS) of preeclampsia was 1.01 (95% confidence interval (CI): 1.01-1.02) when exposed to 30 °C, 1.05 (95%CI: 1.03-1.08) at 35 °C, and 1.07 (95%CI: 1.04-1.10) at 37 °C. The associations existed with both early- and late-onset preeclampsia; however, the associations with the early-onset disease were somewhat stronger, limited to the first weeks of pregnancy and the third trimester, and with larger confidence intervals. The HRCS for early preeclampsia onset, when exposed to 37 °C compared to 22.4 °C during week 33, was 1.12 (95%CI: 0.96-1.30), and for late-onset preeclampsia, the HRCS was 1.09 (95%CI: 1.05-1.13). To conclude, exposure to high temperatures at the beginning and, particularly, the end of gestation is associated with an increased risk of preeclampsia in southern Israel.

Prenatal and postnatal exposure to NO2 and rapid infant weight gain - A population-based cohort study.

BACKGROUND: Childhood overweight and obesity is a global public health problem. Rapid infant weight gain is predictive of childhood overweight. Studies found that exposure to ambient air pollution is associated with childhood overweight, and have linked prenatal exposure to air pollution with rapid infant weight gain. OBJECTIVES: To examine the association between prenatal and postnatal ambient NO2 exposure, a traffic-related marker, with rapid weight gain in infants. METHODS: We carried out a population-based historical cohort study using data from the Israeli national network of maternal and child health clinics. The study included 474,136 infants born at term with birthweight ≥2500 g in 2011-2019 in central Israel. Weekly averages of NO2 concentration throughout pregnancy (prenatal) and the first 4 weeks of life (postnatal) were assessed using an optimized dispersion model and were linked to geocoded home addresses. We modelled weight gain velocity throughout infancy using the SuperImposition by Translation and Rotation (SITAR) method, a mixed-effects nonlinear model specialized for modelling growth curves, and defined rapid weight gain as the highest velocity tertile. Distributed-lag models were used to assess critical periods of risk and to measure relative risks for rapid weight gain. Adjustments were made for socioeconomic status, population group, subdistrict, month and year of birth, and the alternate exposure period - prenatal or postnatal. RESULTS: The cumulative adjusted relative risk for rapid weight gain of NO2 exposure was 1.02 (95% confidence intereval [CI] 1.00, 1.04) for exposure throughout pregnancy and 1.02 (95% CI 1.01, 1.04) for exposure during the first four postnatal weeks per NO2 interquartile range increase (7.3 ppb). An examination of weekly associations revealed that the critical period of risk for the prenatal exposure was from mid-pregnancy to birth. CONCLUSIONS: Prenatal and postnatal exposures to higher concentrations of traffic-related air pollution are each independently associated with rapid infant weight gain, a risk factor for childhood overweight and obesity.

The heritability of weight gain in infancy: A population-based twin study.

BACKGROUND: Rapid weight gain during infancy is a strong predictor of childhood obesity and is affected by genetic and environmental factors. Identifying ages with low heritability will allow for targeted interventions that might be able to prevent the adverse effects of childhood obesity. OBJECTIVES: The objective of the study is to estimate the heritability of weight gain from birth to defined ages during infancy, as well as during 6-month periods from birth to 18 months of age. We address this by leveraging large-scale computerised anthropometric data from the state-run network of well-baby clinics in Israel. METHODS: We performed a population-based twin study. We extracted weight measurements recorded between birth to 24 months from well-baby clinics for 9388 twin pairs born in Israel between 2011 and 2015. The reported sexes of the twins were used as a proxy for their zygosity status. We estimated the heritability of the weight z-score change from birth to specific ages and during particular periods in infancy. To assess the validity of the results, we repeated the analysis in a sub-cohort of twin pairs with complete weight measurements. RESULTS: During the first 2 years of life, heritability was lowest for birthweight ( h 2 = 0.40 ± 0.11 ). Heritability for weight gain since birth was highest at 4 months ( h 2 = 0.87 ± 0.13 ), and then gradually decreased until age 18 months ( h 2 = 0.62 ± 0.13 ). Estimating the heritability in 6-month intervals from birth to 18 months, heritability was highest during the 6-12-month interval ( h 2 = 0.84 ± 0.14 ), and was substantially lower during the subsequent 12-18-month interval ( h 2 = 0.43 ± 0.16 ). CONCLUSIONS: Heritability of weight gain decreases substantially in the second year of life, suggesting that this period could be an appropriate time for interventions for infants who are at an increased risk of childhood obesity.

Risk Factors of Congenital Hypothyroidism in Israel.

BACKGROUND: Congenital hypothyroidism (CH) is the most common preventable cause of mental retardation and delayed growth in children. Several prenatal and environmental factors might be associated with the disease. OBJECTIVES: To determine the prevalence and risk factors of permanent CH and transient congenital hypothyroidism (TCH) in Israel. METHODS: We conducted a retrospective analysis of the Israeli national newborn screening program database from 2011 to 2015. Chi-square and logistic regression were used to assess the association of the demographic and gestational factors with the CH and TCH. RESULTS: Of the 889,033 live births screened between 2011 and 2015, 860 were diagnosed with CH (9.76 per 10,000 live births) and 298 with TCH (3.35 per 10,000 live births). In multivariate analyses, CH was positively associated with female sex, gestational ages < 38 or > 39 weeks, birth weight < 3000 grams, and winter birth. A decreased risk of TCH was detected in Arabs and neonates from high socioeconomic areas. An increased risk was independently associated with gestational ages < 38 weeks, low birth weight, and winter birth. CONCLUSIONS: Several demographic, gestational, and geographical factors are associated with the development of CH and TCH. Future studies are needed to further investigate the pathogenesis in Israel.

Exposure errors due to inaccurate residential addresses and their impact on epidemiological associations: Evidence from a national neonate dataset.

BACKGROUND: Studies assessing the associations between prenatal air pollution exposures and birth outcomes commonly use maternal addresses at the time of delivery as a proxy for residency throughout pregnancy. Yet, in large-scale epidemiology studies, maternal addresses commonly originate from an administrative source. OBJECTIVE: This study aimed to examine the use of population registry addresses to assign exposure estimations and to evaluate the impact of inaccurate addresses on exposure estimates and association measures of prenatal exposures with congenital hypothyroidism. METHODS: We used morbidity data for congenital hypothyroidism from the national program for neonatal screening for 2009-2015 and address data from two sources: population registry and hospital records. We selected neonates with geocoded addresses from both sources (N = 685,491) and developed a comparison algorithm for these addresses. Next, we assigned neonates with exposures from ambient air pollution of PM and NO2/NOX, evaluated exposure assessment differences, and used multivariable logistic regression models to assess the impact that these differences have on association measures. RESULTS: We found that most of the exposure differences between neonates with addresses from both sources were around zero and had a leptokurtic distribution density, with most values being zero. Additionally, associations between exposure and congenital hypothyroidism were comparable, regardless of address source and when we limited the model to neonates with identical addresses. CONCLUSIONS: We found that ignoring residential inaccuracies results in only a small bias of the associations towards the null. These results strengthen the validity of addresses from population registries for exposure assessment, when detailed residential data during pregnancy are not available.

Postnatal exposure to ambient temperature and rapid weight gain among infants delivered at term gestations: a population-based cohort study.

BACKGROUND: The global prevalence of childhood obesity has risen dramatically recently. Previous studies found an association between rapid infant weight gain and childhood overweight. Evidence suggests that exposure to high ambient air temperatures during prenatal life and during adulthood is associated with birthweight and obesity respectively. OBJECTIVE: The objective of this study was to examine whether exposure to high ambient temperatures during infancy is associated with rapid infant weight gain in Israel. METHODS: This is a population-based historical cohort study using data from the Israeli national public network of maternal and child health clinics between 2008 and 2013. We assessed exposure to ambient temperature in the first year of life using a high-resolution hybrid spatio-temporal model and calculated annual mean and minimum temperatures for each infant based on daily mean and minimum temperatures at the community clinic location. We defined rapid infant weight gain as a World Health Organization weight z-score difference >0.67 between birthweight and weight at age one year. We estimated these associations using log-linear and general additive models and adjusted for population group, district, maternal age, parental education, parity, sex, gestational age, birthweight, calendar year and calendar month of birth. RESULTS: The study population included 217,310 singleton-term infants. Adjusted models demonstrated a positive association between ambient temperature exposure and rapid infant weight gain. Compared to the third quintile of minimum temperature, infants exposed to the first and second quintile had an adjusted relative risk of 0.98 (95% CI 0.96, 1.00) and 0.97 (95% CI 0.95, 0.98), respectively, while those exposed to the fourth and fifth quintiles had an adjusted relative risk of 1.06 (95% CI 1.04, 1.07) and 1.02 (95% CI 1.00, 1.04) respectively. The associations with mean temperature were similar but slightly weaker. CONCLUSIONS: Exposure to higher ambient temperatures, of emerging importance in the climate change era, is associated with rapid infant weight gain in Israel. Future studies should use additional exposure, covariate, and outcome data to analyse the nature and the source of this association in more detail.

Air Pollution and Autism Spectrum Disorder in Israel: A Negative Control Analysis.

BACKGROUND: Residual confounding is a major concern for causal inference in observational studies on air pollution-autism spectrum disorder (ASD) associations. This study is aimed at assessing confounding in these associations using negative control exposures. METHODS: This nested case-control study included all children diagnosed with ASD (detected through 31 December 2016) born during 2007-2012 in Israel and residing in the study area (N = 3,843), and matched controls of the same age (N = 38,430). We assigned individual house-level exposure estimates for each child. We estimated associations using logistic regression models, mutually adjusted for all relevant exposure periods (prepregnancy, pregnancy, and postnatal). We assessed residual confounding using postoutcome negative control exposure at age 28-36 months. RESULTS: In mutually adjusted models, we observed positive associations with ASD for postnatal exposures to NOx (odds ratio per interquartile range, 95% confidence interval: 1.19, 1.02-1.38) and NO2 (1.20, 1.00-1.43), and gestational exposure to PM2.5-10 (1.08, 1.01-1.15). The result for the negative control period was 1.04, 0.99-1.10 for PM2.5, suggesting some residual confounding, but no associations for PM2.5-10 (0.98, 0.81-1.18), NOx (1.02, 0.84-1.25), or NO2 (0.98, 0.81-1.18), suggesting no residual confounding. CONCLUSIONS: Our results further support a hypothesized causal link with ASD that is specific to postnatal exposures to traffic-related pollution.

Associations Between Prenatal Exposure to Air Pollution and Congenital Hypothyroidism.

Adequate thyroid hormone availability is required for normal brain development. Studies have found associations between prenatal exposure to air pollutants and thyroid hormones in pregnant women and newborns. We aimed to examine associations of trimester-specific residential exposure to common air pollutants with congenital hypothyroidism (CHT). All term infants born in Israel during 2009-2015 were eligible for inclusion. We used data on CHT from the national neonatal screening lab of Israel, and exposure data from spatiotemporal air pollution models. We used multivariable logistic regression models to estimate associations of exposures with CHT, adjusting for ethnicity, socioeconomic status, geographical area, conception season, conception year, gestational age, birth weight, and child sex. To assess residual confounding, we used postnatal exposures to the same pollutants as negative controls. The study population included 696,461 neonates. We found a positive association between third-trimester nitrogen oxide exposure and CHT (per interquartile-range change, odds ratio = 1.23, 95% confidence interval: 1.08, 1.41) and a similar association for nitrogen dioxide. There was no evidence of residual confounding or bias by correlation among exposure periods for these associations.

Bias due to Selection on Live Births in Studies of Environmental Exposures during Pregnancy: A Simulation Study.

BACKGROUND: Studies of the effects of prenatal environmental exposures on postnatal outcomes are particularly vulnerable to live birth bias; i.e., the bias that arises from the necessary restriction of the analysis to live births when that is influenced by both the exposure under study A and unmeasured factors U that also affect the outcome. OBJECTIVES: In the context of a recent publication of nitrogen dioxide (NO2) and autism spectrum disorder (ASD) that found an odds ratio (OR) of 0.77 per 5.85 ppb NO2 during pregnancy, we aimed to examine what parameters would be needed to account for this protective association through live birth bias. METHODS: We simulated the magnitude of bias under two selection mechanisms and when both mechanisms co-occur, assuming a true null effect. Simulation input parameters were based on characteristics of the original study and a range of plausible values for the prevalence of unmeasured factor U and the ORs for the selection effects (i.e., the effects of NO2 and U on loss and of U on ASD). Each scenario was simulated 1,000 times. RESULTS: We found that the magnitude of bias was small when NO2 and U independently influenced pregnancy loss (collider-stratification without interaction), was stronger when NO2-induced loss preferentially occurred in U=1 (depletion of susceptibles), and was strongest when both mechanisms worked together. For example, ORs of 3.0 for NO2-loss, U-loss, U-ASD, and U prevalence=0.75 yielded NO2-ASD ORs per 5.85 ppb NO2 of 0.95, 0.89, and 0.75 for the three scenarios, respectively. The bias is amplified with multiple Us, yielding ORs as low as 0.51. DISCUSSION: Our simulations illustrate that live birth bias may lead to exposure-outcome associations that are biased downward, where the extent of the bias depends on the fetal selection mechanism, the strength of that selection, and the prevalence of U. https://doi.org/10.1289/EHP7961.

Employment Outcomes After a Birth of a Child with a Developmental Disability: A National Nested Case-Control Study.

Using records from the National Insurance Institute of Israel, we recognized all children with autism spectrum disorders (ASD, N = 8072) or hearing loss (HL, N = 2231) born in Israel between 2005 and 2010. Typical developed children were taken from a random 20% sample of children born during the same years (N = 227,492). Analyses were adjusted for year of birth, population group, parental ages, parental education, child birth order and peripherality. Working women, who gave birth to children with either ASD or HL, were at increased risk of not maintaining their working status over the 5 years after birth. There is a decreased ratio between household wage after and before birth, in families with children with either ASD or HL.

Spatiotemporal distribution of autism spectrum disorder prevalence among birth cohorts during 2000-2011 in Israel.

PURPOSE: Studies indicate an apparent sharp increasing trend in autism spectrum disorder (ASD) incidence and prevalence worldwide. This nationwide study aims at depicting ASD prevalence distribution in Israel in both space and time. METHODS: Based on data from Israel National Insurance Institute, the study population included all children born in Israel 2000-2011 (n = 1,786,194), of whom 11,699 (0.655%) were subsequently diagnosed with ASD (until December 31, 2016). Prevalence was calculated and mapped by dividing the number of ASD cases within each year of birth by the number of births during that year, for each spatial unit, and similarly for several spatiotemporal levels of aggregation. RESULTS: ASD prevalence varies substantially across different geographic areas in Israel, with considerably higher prevalence concentrated in central Israel. Strong associations were found between locality-level socioeconomic index, ethnicity, and peripherality and ASD prevalence, and even after adjustment for them, excess prevalence for ASD still persisted in certain localities. No spatial dependence of prevalence, with and without adjustment for the locality-level variables, was found (Moran's I = -0.000546, -0.00335, respectively). CONCLUSIONS: Our findings provide important insights regarding health disparities affecting ASD diagnosis, directing further health policy intervention and further research.

Prenatal exposure to ambient air temperature and risk of early delivery.

BACKGROUND: Preterm birth is a major determinant of adverse health consequences, and early term births are also associated with increased risk of various outcomes. In light of climate change, the effect of ambient temperature on earlier delivery is an important factor to consider. Several studies have focused on associations of ambient air temperature (Ta) on preterm birth, but few have examined associations with early term births. AIMS: To investigate the association of prenatal exposure to Ta with preterm birth (<37 completed gestation weeks) and with early-term birth (<39 completed gestation weeks) in a semi-arid climate. METHODS: All singleton deliveries at the Soroka Medical Center from the Southern district of Israel, with estimated conception dates between May 1, 2004 and March 31, 2013 (N = 62,547) were linked to prenatal Ta estimates from a spatiotemporally resolved model, with daily 1 km resolution. We used time-dependent Cox regression models with weekly mean Ta throughout gestation, adjusted for calendar month and year of conception, ethnicity, census-level socio-economic status and population density. RESULTS: Ta was positively associated with late preterm birth (31 + 0/7 - 36 + 6/7 weeks), with increased risk in the upper Ta quintile as compared to the third quintile, hazard ratio (HR) = 1.31, 95% confidence interval (CI) = 1.11-1.56. Ta also associated with early term birth (37 + 0/6 - 38 + 6/7), with increased risk in the upper Ta quintile as compared to the third quintile, HR = 1.24, 95% CI = 1.13-1.36. CONCLUSION: Exposure to high ambient temperature during pregnancy is associated with a higher risk of preterm and early term birth in southern Israel.

Emissions vs. turbulence and atmospheric stability: A study of their relative importance in determining air pollutant concentrations.

Air pollution in the urban environment is a major concern. The ambient concentrations depend on the levels of transboundary imported pollution, the intensity of local sources and the prevailing atmospheric conditions. This work studies the relative impact of two atmospheric variables-atmospheric stability and regional scale turbulence-in determining the air pollution concentrations. We considered a setting (downtown Haifa, Israel) impacted by a large variety of sources, emitting pollutants with different chemical attributes and atmospheric life times. We found that traffic accounts for most of the locally produced pollution in the study location. However, the meteorological factors can overwhelm its impact and dictate the concentrations. The switch from stable to convective conditions and the more vigorous daytime wind are associated with a premature end of the morning peak concentrations that result from rush hour emissions of NOx, Black Carbon (BC) and ultra-fine particles. It results in daytime concentration which are lower than (winter) or equal to (summer) those at night, in spite of the much lower night-time traffic volumes. Similar, albeit weaker, impact was detected in the benzene and toluene concentrations. Sources outside the study area are responsible for most of the CO, PM1 and PM2.5 concentrations but during winter nights, characterised by strong atmospheric stability and low turbulence, their concentrations are elevated due to the local emissions. We developed a diagnostic statistical nonlinear model for the pollutant concentrations, which points to a stronger association of the atmospheric stability with the concentrations during stable conditions but turbulence dominating during convective conditions. Our findings explain the relatively low overall concentrations of locally emitted pollutants in the study area but warn of the potential for high concentrations during night-time in locations with comparable meteorological conditions.

Birth weight and autism spectrum disorder: A population-based nested case-control study.

Low birth weight (<2,500 g) and preterm birth (<37 weeks) were found to be associated with increased risk of autism spectrum disorder (ASD), however, the data regarding the entire birth weight (BW) and gestational age (GA) range are inconclusive. In this population nested case-control study, based on the Israeli National Insurance Institute records, we aimed to estimate the associations in the Israeli population. The study population included all children born between 2000 and 2012 and diagnosed with ASD (N = 12,635 cases), and a random 20% sample of children born in the same period who were not diagnosed with ASD (N = 369,548 controls). We used multiple logistic regression models to calculate the risk of ASD for each BW and GA category, adjusted for covariates (child sex, maternal age, paternal age, population group, maternal wage, paternal wage, having a sibling with ASD, multiple gestation and socioeconomic status). BW < 3,000 g and GA < 39 weeks were associated with higher risk of ASD, including BW of 2,500-3,000 g (adjusted odds ratio [AOR], 1.18; 95% CI, 1.12-1.24, in comparison to the 3,000-3,500 g category) and GA of 37 & 38 weeks (AOR, 1.35; 95% CI, 1.25-1.45 and AOR, 1.13; 95% CI 1.06-1.20, respectively; in comparison to GA of 40 weeks). To account for the high correlation between GA and BW, we modeled BW percentiles for gestational age and found that the BW < 20th percentile was associated with an increased risk of ASD (AOR, 1.10; 95% CI, 1.01-1.19). These results demonstrate that associations of ASD with BW and GA are not limited to commonly used clinical cutoffs. Autism Res 2020, 13: 655-665. © 2020 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Autism spectrum disorder (ASD) has been associated with low birth weight (<2,500 g) in prior research. Our study aims to describe the relationship between birth weight (BW) and ASD in the Israeli population. We found that BW <3,000 g was associated with a higher risk of ASD. These results demonstrate that an increased risk of ASD is not confined to clinically defined cutoffs such as BW < 2,500 g.