P-0193 - The implementation of a low emission zone in a medium-sized Swedish city: estimated effects on mortality and morbidity
Abstract Control Number
3302
Abstract Body
Title: The introduction of a low emission zone in a medium-sized Swedish city: estimated effects on morbidity and mortalityAuthors: Anna Oudin1,2, Erin Flanagan1, Ebba Malmqvist11.Occupational and Environmental Medicine, Lund University, Sweden2.Occupational and Environmental Medicine, Umeå University, Sweden
Air pollution is one of the leading causes of morbidity and mortality worldwide. The introduction of low emission zones has been implemented in some cities as a measure to reduce morbidity and mortality caused by air pollution. In other cities, such measures are being considered to be implemented. We undertook a health impact assessment to estimate effects on mortality and morbidity in Malmö by introducing a low emission zone. This was done in dialogue with the Malmö city’s environmental department, assuming adjusted emission factors according to the Handbook Emission Factors for Road Transport version 3.3 with all vehicles on municipal roads being euro6 or better and a mix of vehicles on state roads. The intervention would lead to decreased nitrogen dioxide-levels by in average 2.1 mikrogr/m3 per person (minimum: 0.2, maximum: 5.1 mikrogr/m3). We estimated that the cleaner air would prevent 1-2% of all deaths, depending on what dose-response function was assumed. This corresponds to 26-37 lives per year in Malmö. In comparison in average 7 people die in Malmö each year from traffic accidents. We will also present results regarding how morbidity would be affected.
Air pollution is one of the leading causes of morbidity and mortality worldwide. The introduction of low emission zones has been implemented in some cities as a measure to reduce morbidity and mortality caused by air pollution. In other cities, such measures are being considered to be implemented. We undertook a health impact assessment to estimate effects on mortality and morbidity in Malmö by introducing a low emission zone. This was done in dialogue with the Malmö city’s environmental department, assuming adjusted emission factors according to the Handbook Emission Factors for Road Transport version 3.3 with all vehicles on municipal roads being euro6 or better and a mix of vehicles on state roads. The intervention would lead to decreased nitrogen dioxide-levels by in average 2.1 mikrogr/m3 per person (minimum: 0.2, maximum: 5.1 mikrogr/m3). We estimated that the cleaner air would prevent 1-2% of all deaths, depending on what dose-response function was assumed. This corresponds to 26-37 lives per year in Malmö. In comparison in average 7 people die in Malmö each year from traffic accidents. We will also present results regarding how morbidity would be affected.
P-1096 - Repeated Measures of Polycyclic Aromatic Hydrocarbons are Associated with Reproductive and Thyroid Hormones During Pregnancy
Abstract Control Number
2257
Abstract Body
Polycyclic aromatic hydrocarbons (PAHs) are environmental contaminants produced via incomplete combustion reactions. Human exposure is widespread and occurs via cigarette smoke, charred meats, and automobile exhaust. Recent natural disasters in Puerto Rico have resulted in large numbers of residents relying on gas powered generators for electricity, thus concern about PAH exposures will be heightened in the coming years. Previous studies have demonstrated that PAH exposure may be linked to cardiovascular disease and various cancers, but the mechanisms by which these disease states are affected by PAHs are poorly understood. Therefore, we aimed to investigate the endocrine disrupting potential of PAHs to better understand their physiological impacts. We utilized data from the PROTECT prospective pregnancy cohort in Puerto Rico, in which we had biomarker measurements for 8 urinary PAH metabolites and 9 serum hormones in 1018 pregnant women at two time points (median 18 and 26 weeks) during gestation. Linear mixed models with random intercepts were used to assess longitudinal associations between PAH metabolites and hormone concentrations. Interaction terms were introduced into models to assess differences in observed associations between fetal sexes and between study visits. Significant associations were observed with most PAH metabolites, and some differed by study visit or fetal sex. Notably, an interquartile range (IQR) increase in 2,3-hydroxyphenanthrene was associated with a 19.0% (95% CI: 7.44, 31.7) increase in CRH, and this association was driven by exposure at the first study visit (interaction p-value: 0.027). An IQR increase in 9-hydroxyphenanthrene was associated with a 17.4% (95% CI: 5.18, 28.1) decrease in testosterone among women carrying a female, but not a male, fetus (interaction p-value: 0.006). Our results suggest that exposure to PAHs may disrupt diverse hormonal pathways during pregnancy, and that fetal sex and exposure windows may be important in determining the health effects of PAH exposures.
P-0861 - Prenatal exposure to per- and polyfloroalkyl substances (PFASs) and child growth trajectories in the Norwegian Mother, Father and Child cohort study (MoBa).
Abstract Control Number
2154
Abstract Body
Early life low dose exposure to PFASs has been negatively associated with fetal growth, but the long-term effects on postnatal child growth are unknown. The interplay of additional factors that are important for postnatal growth, such as breastfeeding and sleep habits is also unknown. In 3,882 mother-child pairs from the MoBa study, we examined the associations between prenatal PFASs exposure and child body weight trajectories. The concentrations of 11 PFASs were measured in maternal blood (at 17-18 gestational weeks): perfluorohexanesulfonate (PFHxS), perfluoroheptanesulfonate (PFHpS), perfluorooctanesulfonate (PFOS), perfluoroheptanoate (PFHpA), perfluorooctanoate (PFOA), perfluorononanoate (PFNA), perfluorodecanoate (PFDA), perfluoroundecanoate (PFUnDA), perfluorododecanoate (PFDoDA), perfluorotridecanoate (PFTrDA), perfluorooctanesulfonamide (PFOSA). Individual growth trajectories were computed by modelling based on child’s reported weight at 11 time points from 6 weeks to 8 years. For most PFASs exposure was categorized into quartiles, while PFHpA, PFOSA, PFDoDA and PFTrDA were dichotomized (<LOD/≥LOD). We used single-contaminant linear mixed effect regression models and studied interactions with breastfeeding duration (<6 months/≥6 months) and sleep duration at 6 months (less/as recommended (12-16 hours/day). At 1.5 months, children born to mothers with PFDA levels in Q2 weighed 57g (95%CI=1,114g) more than their lower exposed peers (Q1). During the first 6 months, children prenatally exposed to PFUnDA level at Q2 weighed -53 to -56g (95%CI range=-116,4g) less than those in Q1. Among longer breastfed children (67%), we found a larger weight reduction corresponding to prenatal PFUnDA Q2 vs. Q1 (-94 to -81g, 95%CI range=-159, -11g). Among children with shorter sleep (4%), higher prenatal exposure to PFUnDA (Q2), PFHxS (Q4), PFHpS (Q3) and PFTrDA (≥LOD) was associated with reduced weight trajectories, compared to Q1. In this preliminary analysis of a European population with background exposure to PFASs, we observed negative associations between prenatal PFASs exposure and postnatal child growth which seemed stronger in breastfed and lower sleepers.
P-0340 - The impact of ambient temperature on adverse pregnancy outcomes in Ahvaz, Iran; 2008-2018
Abstract Control Number
2022
Abstract Body
The impact of ambient temperature on adverse pregnancy outcomes in Ahvaz, Iran; 2008-2018
AbstractBackground: There are few epidemiological studies on the relation between temperature changes and adverse pregnancy outcomes. The purpose of this study was to determine the relation between Diurnal Temperature Range (DTR), Physiological Equivalent Temperature (PET) and Universal Thermal Climate Index (UTCI) with adverse pregnancy outcomes including stillbirth, low birth weight (LBW), preterm labor (PTL), spontaneous abortion (SA), preeclampsia and gestational hypertension in Ahvaz, Iran. Methods: Distributed Lag Non-linear Models (DLNM) combined with quasi-Poisson regression were used to investigate the effect of DTR, PET and UTCI on adverse pregnancy outcomes. In this study the effect of time trend, air pollutants (NO2, SO2 and PM10), and weekdays were adjusted. Results: Cold thermal stress in the DTR index (the 1st percentile (2.7 C°) compared to 25th percentile (11.9 C°) significantly increased the risk of abortion in the cumulative lags of 0-6, 0-13 and 0-21. High PET (45.4 C°, lag = 0) caused a significant increase in risk of stillbirth. Also, high levels of PET (45.4, 43.6, 42.5 C°, lag = 0-6) and low levels of PET (9.9, 16.9 C°, lags=0, 0-13, 0-21) significantly increased the risk of LBW. But, low levels of PET (6.4, 9.9, 16.9 C°, lags = 0-6, 0-13) reduced the risk of gestational hypertension. Low values of UTCI index (11.6 C°, lags = 0-6, 0-13) caused significant increase in risk of preterm labor. Finally, hot thermal stress in the UTCI index significantly increased the risk of stillbirth in 0-13 lag. Conclusions: The results of this study showed that hot and cold thermal stress are associated with increased risk of stillbirth, LBW, PTL and SA; in Ahvaz.
AbstractBackground: There are few epidemiological studies on the relation between temperature changes and adverse pregnancy outcomes. The purpose of this study was to determine the relation between Diurnal Temperature Range (DTR), Physiological Equivalent Temperature (PET) and Universal Thermal Climate Index (UTCI) with adverse pregnancy outcomes including stillbirth, low birth weight (LBW), preterm labor (PTL), spontaneous abortion (SA), preeclampsia and gestational hypertension in Ahvaz, Iran. Methods: Distributed Lag Non-linear Models (DLNM) combined with quasi-Poisson regression were used to investigate the effect of DTR, PET and UTCI on adverse pregnancy outcomes. In this study the effect of time trend, air pollutants (NO2, SO2 and PM10), and weekdays were adjusted. Results: Cold thermal stress in the DTR index (the 1st percentile (2.7 C°) compared to 25th percentile (11.9 C°) significantly increased the risk of abortion in the cumulative lags of 0-6, 0-13 and 0-21. High PET (45.4 C°, lag = 0) caused a significant increase in risk of stillbirth. Also, high levels of PET (45.4, 43.6, 42.5 C°, lag = 0-6) and low levels of PET (9.9, 16.9 C°, lags=0, 0-13, 0-21) significantly increased the risk of LBW. But, low levels of PET (6.4, 9.9, 16.9 C°, lags = 0-6, 0-13) reduced the risk of gestational hypertension. Low values of UTCI index (11.6 C°, lags = 0-6, 0-13) caused significant increase in risk of preterm labor. Finally, hot thermal stress in the UTCI index significantly increased the risk of stillbirth in 0-13 lag. Conclusions: The results of this study showed that hot and cold thermal stress are associated with increased risk of stillbirth, LBW, PTL and SA; in Ahvaz.
P-1015 - Imputation methods for addressing missing data in short-term monitoring of air pollutants
Abstract Control Number
1904
Abstract Body
Background: Monitoring of environmental contaminants is a critical part of exposure sciences and epidemiological research. Missing data are often encountered when performing short-term monitoring (<24hr) of air pollutants with real-time monitors, especially in resource-limited areas. Approaches for handling consecutive periods of missing and incomplete data in this context remain unclear. Our aim is to evaluate existing imputation methods for handling missing data for real-time monitors operating for short durations.Methods: In a current field-study, real-time particulate monitors were placed outside of 20 households for 24-hours. Missing data was simulated at four consecutive periods of missingness (20%, 40%, 60%, 80%). Univariate (Mean, Median, Last Observation Carried Forward, Kalman Filter, Random, Markov) and multivariate time-series (Predictive Mean Matching, Row Mean Method) methods were used to impute missing concentrations, and performance was evaluated using five error metrics (Absolute Bias, Percent Absolute Error in Means, R2 Coefficient of Determination, Root Mean Square Error, Mean Absolute Error). Results: Univariate methods of Markov, random, and mean imputations performed best, yielding 24-hour mean concentrations with low error and high R2 values across all levels of missingness. When evaluating error metrics minute-by-minute, Kalman Filters, median, and Markov methods performed well at low levels of missingness (20-40%). However, at higher levels of missingness (60-80%), Markov, random, median, and mean imputation performed best on average. Multivariate imputation methods performed worst across all levels of missingness. Conclusion: Epidemiological studies often report pollutant concentration in relationship to their potential health effect by averaging minute or hourly concentrations over 24-hours. However, when more than 25% of data is missing, daily average pollutant concentrations cannot be reliably computed. Univariate imputation may provide a reasonable solution to addressing missing data for short-term monitoring of air pollutants. Further efforts are needed to evaluate imputation methods that are generalizable across a diverse range of study environments.
P-0444 - Health surveillance of healthcare workers exposed to SARS-Cov-2 in Milan, Italy
Abstract Control Number
3314
Abstract Body
Background: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection recently became an issue of national relevance in Italy, especially in healthcare workers (HCWs) who have been exposed to the virus in times when preventive measures were not yet fully established. Methods: We collected occupational and clinical characteristics of all HCWs who had performed a nasopharyngeal swab for the detection of SARS-CoV-2 at the Policlinico Hospital in Milan, the capital city of Lombardy (the most affected Italian region), from February 24th to March 31st 2020. Laboratory data were collected as of April 9th. We compared frequencies of positive tests according to selected variables using chi-squared test and applied multivariable logistic regression models including gender, age class, occupation, and reported symptoms. Results: We found 138 test-positive HCWs out of a total of 1,573 (8.8%, 95% confidence interval [CI]: 7.4-10.3). Symptomatic subjects showed a much higher proportion of positive tests (20.2%, 95%CI: 16.7-24.1) when compared to asymptomatic ones (3.7%, 95%CI: 2.7-5.1, p<0.001). The strongest predictors of a positive test were fever (Odds ratio [OR] = 7.21, 95%CI: 4.45-11.7) and taste and smell alterations (OR = 29.7, 95%CI: 10.1-87.5). Fifty percent of subjects took up to 23 days (95%CI: 19-24) to become negative from first positive test. When considering occupation, the highest frequency of positive tests was detected among physicians (10.6%, 95%CI: 8.3-13.4). Conclusions: In a sample of HCWs exposed to confirmed cases of COVID-19, we found fever and taste and smell alterations to be strongly associated with SARS-CoV-2 infection, together with a median time to clear the virus of 23 days. The investigation in the Hospital is currently continuing by performing serological tests for identification of SARS-CoV-2 S1/S2 IgG antibodies including also the present study subjects. This will allow to assess the presence of specific antibodies to be compared with nasal swab tests.
P-0422 - Environmental Cadmium, Influenza-related Mortality in U.S. Adults, and Implications for the COVID-19 Pandemic
Abstract Control Number
3206
Abstract Body
Background/Aim: Cadmium exposure is widespread, accumulates in the body, triggers pulmonary inflammation, is associated with decrements in respiratory function, and has been shown to enhance lung injury by respiratory syncytial virus. Our aim was to examine the association of cadmium burden with influenza-related mortality in U.S. adults. Methods: This prospective cohort study of the National Health and Nutrition Examination Survey (NHANES) included 7179 and 8682 participants aged 45 years and older enrolled from NHANES-3 and NHANES 1999-2006, respectively. Associations were evaluated between urinary and blood concentrations of cadmium and mortality from influenza and pneumonia during a median follow-up of 17.3 years (NHANES-3) and 11.4 years (NHANES 1999-2006). Survey-weighted Cox proportional hazard models were used to compute hazard ratios (HRs) comparing the mortality experience of individuals at the 80th v. the 20th percentile of the distribution of cadmium biomarker levels. Results: In NHANES-3 (141 deaths from influenza/pneumonia, incidence rate=1.24 per 1000 person-years), creatinine-corrected cadmium was associated with a hazard ratio (HR) of 1.16 (95% CI, 1.07-1.26; P=0.0004) after adjustment for age, sex, race/ethnicity, education, body mass index, serum cholesterol, and hypertension. The HR was 1.23 (95% CI, 1.07-1.43; P=0.005) when the analysis was restricted to never smokers. In NHANES 1999-2006 (56 deaths from influenza/pneumonia, incidence rate=0.59 per 1000 person-years), blood cadmium was associated with an adjusted HR of 1.16 (95% CI, 0.98-1.37; P=0.08); and 1.69 (95% CI, 0.97-2.97; P=0.07) in never smokers. The pooled HRs combining both datasets were 1.16 (95% CI, 1.08-1.25); and 1.26 (95% CI, 1.09-1.45) in never smokers. Conclusions and Relevance: Higher cadmium burden is associated with higher mortality from influenza/ pneumonia among middle-aged and older adults in the US general population. Higher cadmium burdens may also worsen outcomes from COVID-19 infections.
P-1145 - NCEH/ATSDR Microplastic Working Group: Identifying and Addressing Data Needs to Evaluate Human Exposures to Microplastics
Abstract Control Number
1738
Abstract Body
Microplastics are environmentally persistent pollutants characterized by their diverse composition and small size (<5mm). Microplastics can be manufactured like microbeads, tire crumb, polyester fibers from clothing and carpets, and result from fragmentation processes of plastics disposed in the environment. Microplastics pervade our environment and human exposure is certain. However, exposure-dose and possible health effects have not been established. Some microplastic fibers and particles are small enough to become internalized and transported within our bodies (e.g. respirable particles PM10 and 2.5; particles 0.02-0.05 µm in size can passively drain through lymphatics). However, most of the environmental samples collected have been characterized as larger particles that are unlikely to be absorbed. Other relevant considerations include the composition and physicochemical characteristics of plastics (shape, density, and surface chemistry), and the composition of additives and absorbed or adsorbed contaminants. The array of variables, and uncertainty as to which may be most relevant to health pose challenges for exposure assessment. The CDC National Center for Environmental Health (NCEH) and the Agency for Toxic Substances and Disease registry (ATSDR) developed a microplastics working group with a vision and objectives to: 1. Identify the scientific information and data that are lacking to define health risks; 2. Create constructive partnerships to broaden outreach;3. Energize communities and institutions to develop initiatives to stop harmful microplastic exposures in our environment. In this poster, we will highlight activities that the NCEH/ATSDR working group has conducted to accomplish the objectives. We will also present an overview of what is known about the fate and transport of microplastics in the environment, and potential human exposures from drinking water, air, and food. Data gaps will be highlighted that may inform policy-relevant research roadmap to address the many uncertainties in this important area.
P-0913 - Sickle Cell Disease-Related Hospital Admissions and Acute Particulate Matter 2.5 Exposures
Abstract Control Number
2868
Abstract Body
BackgroundFew studies have examined the impact of ambient air pollution exposures on sickle cell disease (SCD)- related hospital admissions. The findings of these studies have suggested potential relationships between SCD-related hospital admissions with acute exposures to ozone and particulate matter but the findings have been inconsistent. MethodsWe evaluated the association between acute exposure to ambient particulate matter 2.5 (PM2.5) air pollution and SCD-related hospital admissions among residents of South Carolina (SC). We obtained data on the first incident hospital admission between 2003 and 2006. PM2.5 exposures were estimated at the residential zip code level using spatio temporal statistical modeling. We used a semi-symmetric bidirectional case-crossover design to examine the association between hospital admissions and PM2.5 exposures 0 to 7 days prior to hospital admission (for the case period) and an equivalent 0 to 7 day control period within the same month, same days of the week. Conditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs).ResultsAmong 1,937 individuals with at least one SCD hospital admission, the median age was 22 years, and the median percentage of persons living below poverty in the census tract of residence was about 16%. The average PM2.5 estimated exposure was about 10.1 ug/m3 on the day of hospital admission. The OR between admission and PM2.5 exposures on the day prior was 1.02 (95%CI: 1.00,1.03) while all other time windows examined hovered around 1.00 and were not statistically significant. ConclusionsWe observed some suggestion of increased risk for SCD-related hospital admission with an increase in PM2.5 exposures on the day prior to admission. However further investigation is needed to confirm these results.
P-0118 - Ambient Air Pollutants and Skin Cancer: Epidemiological Evidence from UK Biobank
Abstract Control Number
1625
Abstract Body
Background and aim: The impacts of air pollutants on skin cancer remain controversial due to different results of studies. The research aims to investigate the association between exposure to traffic-related pollutants and skin cancer in the United Kingdom (UK). Methods: The UK Biobank is a large population-based, prospective study with over half a million participants aged 40 to 60 years recruited from 2006 to 2010. Data on air pollutants including particulate matter (PM), nitrogen dioxide (NO2), and nitrogen oxides (NOx) between 2005 and 2010 were obtained. Binary logistic regression models were used to assess the association between the concentration of air pollutants and skin cancer after controlling for various confounders. Furthermore, a non-parametric classification tree model was used to evaluate the interactive effect of risk factors on the occurrence of skin cancer. Results: A total of 320,264 participants (48.7% men) aged 64±8 years were included in this study. During a median of 7.8 years of follow-up, 9164 cases of skin cancer occurred in UK. Our results showed that the concentration of air pollutants was a significantly negative correlation with skin cancer. For PM with an aerodynamic diameter of less than 2.5μm (PM2.5) and 10μm (PM10), the odds ratios (OR) were 0.953 (95% confidence interval [CI]: 0.927-0.979) and 0.937 (95%CI: 0.913-0.962) per interquartile range (IQR) increase, respectively. Similar results were observed on NO2 (OR: 0.923, 95%CI: 0.898-0.950) and NOx (OR: 0.940, 95%CI: 0.915-0.964) per IQR increase. The classification tree model showed interactive associations between risk factors and skin cancer. Conclusions: The research demonstrated that air pollutions may lower the risk of skin cancer in UK. However, further research is needed for examining the interactive relationship between air pollutants, ultraviolet index and skin cancer.
P-0658 - Environmental Chemicals and Red Blood Cell Folate levels in the U.S. Population, NHANES
Abstract Control Number
2753
Abstract Body
Background/Aim: Inadequate folate during pregnancy has been associated with congenital birth deficits and adverse neurodevelopmental outcomes, including autism spectrum disorders. Recent studies show that folic acid supplementation may protect against the potential adverse effects of gestational chemical exposures on neurodevelopment. However, it is unclear whether these chemicals impact folate metabolism. Therefore, we investigated the relationship between environmental chemicals and red blood cell (RBC) folate concentrations.Methods: We assessed associations of 41 chemical biomarkers including metals, phthalate metabolites, per- and polyfluroalkyl substances (PFAS), parabens, and polycyclic aromatic hydrocarbons with RBC folate concentrations in 41,433 participants ages 1-80 from the U.S. National Health and Nutrition Examination Survey (2007-2016). We triangulated evidence from three statistical methods developed to examine chemical mixtures: Exposome Wide Association (ExWAS), Bayesian Kernel Regression (BKMR), and SuperLearner with G-computation. We examined the individual and joint associations of these chemicals with RBC folate concentrations, while adjusting for confounders. Results: The geometric mean RBC folate was 463 ng/mL (Interquartile range: 361 - 587.2 ng/mL). Some metals, PFAS, phthalates, and cotinine were consistently associated with lower RBC folate concentrations. Using BKMR, an interquartile range increase in perfluorononanoic acid (PFNA), cotinine, mono-ethyl phthalate, and lead was associated with a -0.15 standard deviation (SD) (95% confidence interval (CI): -0.23, -0.07), -0.11 SD (95% CI: -0.17, -0.03), -0.03 SD (95% CI: -0.07, 0.02), and -0.18 SD (95% CI: -0.25, -0.10) decrease in RBC folate concentrations, respectively. Estimates differed slightly between methods, but these findings remained robust. Conclusion: This study, which is the first to examine an association between a mixture of environmental chemicals and RBC folate concentrations in a nationally representative sample, may help enhance our understanding of the interplay between environmental chemicals, folate, and adverse health outcomes.