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At least 793 records · Page 44
All sourcesNASA NTRSDOE OSTI
NASA NTRS2022

Real-Time Exposure Control and Instrument Operation With the NEID Spectrograph GUI

The NEID spectrograph on the WIYN 3.5-m telescope at Kitt Peak has completed its first full year of science operations and is reliably delivering sub-m/s precision radial velocity measurements. The NEID instrument control system uses the TIMS package (Bender et al. 2016), which is a client-server software system built around the twisted python software stack. During science observations, interaction with the NEID spectrograph is handled through a pair of graphical user interfaces (GUIs), written in PyQT, which wrap the underlying instrument control software and provide straightforward and reliable access to the instrument. Here, we detail the design of these interfaces and present an overview of their use for NEID operations. Observers can use the NEID GUIs to set the exposure time, signal-to-noise ratio (SNR) threshold, and other relevant parameters for observations, configure the calibration bench and observing mode, track or edit observation metadata, and monitor the current state of the instrument. These GUIs facilitate automatic spectrograph configuration and target ingestion from the nightly observing queue, which improves operational efficiency and consistency across epochs. By interfacing with the NEID exposure meter, the GUIs also allow observers to monitor the progress of individual exposures and trigger the shutter on user-defined SNR thresholds. In addition, inset plots of the instantaneous and cumulative exposure meter counts as each observation progresses allow for rapid diagnosis of changing observing conditions as well as guiding failure and other emergent issues.

Arvind F Gupta↗
NASA NTRS2024

Constraining the Surface Exposure Age of Asteroid Bennu Using Cosmogenic Radionuclides in an OSIRIS-REx Aggregate Sample and Individual Particles

Observations by NASA’s OSIRIS-REx spacecraft of asteroid Bennu revealed evidence that this small rubble-pile asteroid experiences several active surface processes that likely control its recent surface exposure history. In October 2020, the spacecraft collected a surface sample from a relatively young ~20 m diameter crater (Hokioi) on asteroid Bennu, and the sample was successfully delivered to Earth on September 24, 2023. Based on the population of craters >50 m diameter, Bennu’s surface is 0.1–1 Ga old, but the old surface is affected by recent processes including smaller meteoroid impacts, mass movement, and particle ejections. The sampling location within Hokioi crater was selected based on its relatively flat surface devoid of large boulders, but the crater floor is also believed to be one of the youngest surfaces on asteroid Bennu, with an age of <100 kyr. As the crater is ~2 m deep, the samples that were collected by OSIRIS-REx may have been relatively shielded from cosmic rays during most of its recent history. This scenario is different from the samples that were collected by Hayabusa2 from asteroid Ryugu, where cosmogenic noble gas and radionuclides indicate cosmic-ray exposure (CRE) ages of ~5 Myr near the surface. Our goal is to understand the recent exposure history of surface samples of asteroid Bennu utilizing radionuclides ( 10 Be, 26 Al, 36 Cl, 41 Ca) produced by both galactic (GCR) and solar (SCR) cosmic rays. With half- lives ranging from 0.1 to 1.36 million years (Myr), the concentrations of these cosmogenic nuclides provide information on the duration and exposure conditions (irradiation depth) of these samples on a timescale of a few Myr. This work will test one of the OSIRIS-REx mission’s driving hypotheses about asteroid Bennu’s recent evolution: that Hokioi crater is part of a population of small (25 m) spectrally red craters on Bennu that are less than 0.1 Myr old.

K. C. Welten↗
NASA NTRS2024

Assessing the effects of landcover and land use change on wildfire exposure and risk to communities and olive orchards in Mediterranean landscapes

A growing concern in the Mediterranean region is that recent landcover and land use change is increasing wildfire risk, or the exposure and impacts of wildfire to valued resources. However, the magnitude of these effects is not well understood given the widely diverse landscapes of communities, natural vegetation, and agricultural land. In this study, we use wildfire simulation modeling to assess how landcover and land use changes in three areas of southern Greece have affected exposure of- and fire risk to- communities and economically important permanent agriculture such as Olea europaea (European olive) orchards. We mapped agricultural and wildland fuel change from 2000 to 2020 and simulated fuel scenarios in agricultural land to assess the impacts of agricultural land practices, such as understory clearing, on fire risk. We show that wildfire exposure and risk to communities and permanent agriculture has increased in some areas due to natural fuel densification and decreased in other areas, mainly due to agricultural land expansion. These results highlight that wildfire exposure and risk are driven by local conditions including density and location of communities, spatial arrangement of natural fuels and agricultural land, and agricultural land use practices. Human settlement burn probability and modeled permanent crop loss increased with greater unmaintained agricultural area in all study areas, emphasizing the importance of agricultural land maintenance practices, such as understory clearing, to reduce fuel continuity and fire intensity. Ultimately, quantitative fire risk analyses such as this study provide a useful framework to identify areas of concern where either fuel mitigation or landowner incentives to maintain agricultural land in a less-burnable condition could be applied.

Aaron M Sparks↗
DOE OSTI2011

What Have "Omics" Taught Us about the Health Risks Associated with Exposure to Low Doses of Ionizing Radiation

There is a plethora of data available on the DNA damages associated with exposures to ionizing radiation and the subsequent cellular responses. Indeed, much of radiation research has focused on these initial insults and induced responses, particularly DNA repair, cell signaling pathways, cell cycle checkpoint control, mutation induction, chromosomal rearrangements, transformation and apoptosis etc. While many of these endpoints correlate with exposure dose, few, if any, provide substantive information on human health risk(s) associated with radiation exposure. Here the contribution of recent advances in high throughput ‘omics technologies are evaluated to examine what they have taught us about health risk(s) to humans associated with exposure to ionizing radiation.

Morgan, William F.↗
DOE OSTI2022

The effect of barrier films and exposure on the aging of vacuum insulation panels with fumed silica cores

Vacuum insulation panels have very low thermal conductivities compared to conventional insulation materials. The reduction of the core pressure significantly lowers gas phase conduction and overall thermal conductivity. As a consequence, increases in gas pressure can significantly increase thermal conductivity of the VIP. In addition, the thermal conductivity of the core is sensitive to moisture content. For vacuum insulation panels with fumed silica cores, work shows that the measured thermal conductivity increases by 0.5 x 10-3 W/mK per mass percent increase in water content [1]. This is significant since the thermal conductivity of vacuum insulation panels with fumed silica cores is in the range of 0.004 W/mK. This work investigates the long-term behavior of vacuum insulation panels comprised of fumed silica cores with polymer (ethylene vinyl alcohol) and metalized (aluminized) barrier films exposed to different exposure conditions: ambient conditions; exterior conditions in a mixed humid climate; and 24oC and 80 percent relative humidity. Results show that the increase in thermal conductivity is more pronounced for vacuum insulation panels made using polymer barrier films compared to the same panel protected by a metalized film. The increase is more pronounced when exposed to high relative humidity, 80 percent. After almost two years exposure, the decrease in thermal conductivity for vacuum insulation panels protected by a metalized barrier films are between 4 and 11 percent depending on exposure condition. The smallest decrease is for ambient conditions where the largest decrease is for exposure to 80 percent relative humidity. Similar behavior was observed for panels protected using polymer films, except the decrease in thermal conductivity was significantly higher, between approximately 20 and 60 percent, in the same order as for panels protected by metalized films. Measurements are ongoing with an attempt to develop a better relationship between these types of tests and vacuum insulation panel service life.

Aldykiewicz Jr, Antonio↗
DOE OSTI2013

Critical Dose of Internal Organs Internal Exposure - 13471

The health threat posed by radionuclides has stimulated increased efforts to developed characterization on the biological behavior of radionuclides in humans in all ages. In an effort motivated largely by the Chernobyl nuclear accident, the International Commission on Radiological Protection (ICRP) is assembling a set of age specific biokinetic models for environmentally important radioelements. Radioactive substances in the air, mainly through the respiratory system and digestive tract, is inside the body. Radioactive substances are unevenly distributed in various organs and tissues. Therefore, the degree of damage will depend not only on the dose of radiation have but also on the critical organ, which is the most accumulation of radioactive substances, which leads to the defeat of the entire human body. The main objective of radiation protection, to avoid exceeding the maximum permissible doses of external and internal exposure of a person to prevent the physical and genetic damage people. The maximum tolerated dose (MTD) of radiation is called a dose of radiation a person in uniform getting her for 50 years does not cause changes in the health of the exposed individual and his progeny. The following classification of critical organs, depending on the category of exposure on their degree of sensitivity to radiation: First group: the whole body, gonads and red bone marrow; Second group: muscle, fat, liver, kidney, spleen, gastrointestinal tract, lungs and lens of the eye; The third group: bone, thyroid and skin; Fourth group: the hands, forearms, feet. MTD exposure whole body, gonads and bone marrow represent the maximum exposures (5 rem per year) experienced by people in their normal activities. The purpose of this article is intended dose received from various internal organs of the radionuclides that may enter the body by inhalation, and gastrointestinal tract. The biokinetic model describes the time dependent distribution and excretion of different radionuclides that have intake into the organism or absorbed into blood. Transport of different radionuclides between compartments is assumed to follow first order kinetics provided the concentration in red blood cells (RBCs) stays below a nonlinear threshold concentration. When the concentration in RBCs exceeds that threshold, the transfer rate from diffusible plasma to RBCs is assumed to decrease as the concentration in RBCs increases. For the calculations used capabilities AMBER by using the traces of radionuclides in the body. Model for the transfer of radionuclides in the body has been built on the basis of existing models at AMBER for lead. (authors)

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2018

Prenatal exposure to mercury and longitudinally assessed fetal growth: Relation and effect modifiers

Highlights: • The largest of two studies on the relation between mercury exposure and fetal growth. • Study on pregnant women from a general population exposed to relatively elevated mercury levels. • Mercury exposure associated with decreased biparietal diameter early in pregnancy. • An antagonism between PCB153 and mercury was found. • Higher decreases in fetal parameters were observed in fetuses with lower PCB153. Prenatal mercury exposure has been related to reductions in anthropometry at birth. Levels of mercury have been reported as being relatively elevated in the Spanish population.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Systemic inflammatory markers associated with cardiovascular disease and acute and chronic exposure to fine particulate matter air pollution (PM2.5) among US NHANES adults with metabolic syndrome

Highlights: • A cross sectional study of the effect of PM{sub 2.5} AP on inflammatory biomarkers among NHANES participants was conducted. • Participants’ Census tract of residence was linked to USEPA downscaler modeled air pollution for the continental US. • Goal was the assessment of susceptibility of adults with metabolic syndrome to PM2.5 exposure and levels of CRP and WBC. • There was a significant effect of PM2.5 at lag day 0; a 10 µg/m3 rise was associated with a 10.1% increase in CRP level. • There were no significant associations with CRP or WBC for those without metabolic syndrome. There has been no investigation to date of adults with metabolic syndrome examining the association of short and long-term exposure to fine particulate matter (PM{sub 2.5}) air pollution with cardiovascular-disease related inflammatory marker (WBC and CRP) levels in a nationally representative sample. The goal of this study is to assess the susceptibility of adults with metabolic syndrome to PM{sub 2.5} exposure as suggested by increased cardiovascular-disease related inflammatory marker levels.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Association between fetal exposure to phthalate endocrine disruptor and genome-wide DNA methylation at birth

Highlights: • Humans are ubiquitously exposed to phthalates through digestion, inhalation, or dermal absorption. • DNA methylation has been hypothesized to be an important mechanism in in utero phthalate exposure. • DNA methylation changes are involved in androgen response, estrogen response, protein secretion, and spermatogenesis. • Three CpG sites (cg00935782, cg07732421, and cg00764560) are involved in genes of response to androgen. Phthalic acid esters are ubiquitous and antiandrogenic, and may cause systemic effects in humans, particularly with in utero exposure. Epigenetic modification, such as DNA methylation, has been hypothesized to be an important mechanism that mediates certain biological processes and pathogenic effects of in utero phthalate exposure.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2015

Phthalate exposure and childrens neurodevelopment: A systematic review

Background: Emerging evidence from observational studies suggests that prenatal exposure to phthalates affects neurodevelopment in children. Objective: To conduct a systematic review of the existing literature on the association between urinary phthalate concentrations and children's neurodevelopment. Methods: We searched electronic bibliographic databases (MEDLINE, PubMed, EMBASE, PsycINFO, CINAHL, Global Health, CAB abstracts, and ERIC) (1910 to February 21st, 2014); reference lists of included articles, and conference abstracts (American Psychiatric Association, American Academy of Neurology, and Pediatric Academic Societies). Two independent reviewers screened abstracts and extracted data. We included original studies reporting on the association between prenatal or childhood urinary phthalate metabolites, and cognitive and behavioral outcomes (e.g., IQ scores, BASC-2 scores or equivalent) in children 0–12 years of age. Results: Of 2804 abstracts screened, 11 original articles met our criteria for inclusion. Conclusions: A systematic review of the literature supports the contention that prenatal exposure phthalates is associated with adverse cognitive and behavioral outcomes in children, including lower IQ, and problems with attention, hyperactivity, and poorer social communication. Further research characterizing the associations between specific phthalate metabolites and children's neurodevelopmental outcomes is needed to support the development of mitigation strategies and enhance the development of appropriate health policy. - Highlights: • Prenatal maternal urinary concentrations of phthalate metabolites appear to be associated with adverse cognitive and behavioral outcomes in children. • Both low molecular weight (e.g., monobutyl phthalate, MBP) and high molecular weight (e.g., di(2-ethylhexyl) phthalate, DEHP) phthalate metabolites are associated with adverse cognitive and behavioral outcomes. • Sex-specific effects from phthalate exposure were noted between low (e.g., mono-n-butyl phthalate, MnBP) and high (e.g., DEHP) molecular weight phthalate metabolites, and cognitive and behavioral outcomes.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Latent class analysis to model multiple chemical exposures among children

Highlights: • Latent class analysis identified subgroups of children with unique chemical exposure profiles. • Three subgroups were identified. • One subgroup comprised children with high multiple co-exposures. • Latent classes were sometimes associated with lymphocyte and neutrophil counts. Children are exposed to multiple potentially harmful chemicals simultaneously. Efforts to understand the patterns and consequences of these exposures have been hampered by statistical limitations in estimations of higher order interactions.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Cause-specific stillbirth and exposure to chemical constituents and sources of fine particulate matter

Highlights: • Explored associations between cause-specific stillbirth and PM{sub 2.5} sources. • Gestational age-adjusted exposure was estimated in nested case-control study design. • Different causes of stillbirth were associated with different pollutants. • Highlighted the importance of investigating cause-specific stillbirth. The stillbirth rate in the United States is relatively high, but limited evidence is available linking stillbirth with fine particulate matter (PM{sub 2.5}), its chemical constituents and sources. In this study, we explored associations between cause-specific stillbirth and prenatal exposures to those pollutants with using live birth and stillbirth records from eight California locations during 2002–2009. ICD-10 codes were used to identify cause of stillbirth from stillbirth records. PM{sub 2.5} total mass and chemical constituents were collected from ambient monitors and PM{sub 2.5} sources were quantified using Positive Matrix Factorization. Conditional logistic regression was applied using a nested case-control study design (N = 32,262). We found that different causes of stillbirth were associated with different PM{sub 2.5} sources and/or chemical constituents. For stillbirths due to fetal growth, the odds ratio (OR) per interquartile range increase in gestational age-adjusted exposure to PM{sub 2.5} total mass was 1.23 (95% confidence interval (CI): 1.06, 1.44). Similar associations were found with resuspended soil (OR=1.25, 95% CI: 1.10, 1.42), and secondary ammonium sulfate (OR=1.45, 95% CI: 1.18, 1.78). No associations were found between any pollutants and stillbirths caused by maternal complications. This study highlighted the importance of investigating cause-specific stillbirth and the differential toxicity levels of specific PM{sub 2.5} sources and chemical constituents.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Spatial analysis of concentrations of multiple air pollutants using NASA DISCOVER-AQ aircraft measurements: Implications for exposure assessment

Highlights: • Aircraft measurements showed spatially varying relations of multiple air pollutants. • NO{sub x}, toluene, and xylenes/ethylbenzene were reasonable proxies of traffic and urban air pollution. • Between-pollutant concentration correlations and ratios varied by space. • Multiple pollutant relations provided insights for exposure assessment and multipollutant epidemiology. In recent years, multipollutant approaches have been employed to investigate the association with health outcomes to better represent real-world conditions than more traditional analysis that considers a single pollutant. With regard to the exposure assessment of a mixture of air pollutants, it is critical to understand the spatial variability in multipollutant relations in order to assess their potential health implications. In this study, we investigated the spatial relations of multiple pollutant concentrations (i.e., NO{sub x}, NO{sub y}, black carbon, carbon monoxide, acetaldehyde, formaldehyde, toluene, xylenes/ethylbenzene, ozone, water-soluble organic carbon, and aerosol extinction) observed from the P-3B aircraft in the 2011 NASA field campaign in Baltimore/Washington D.C. areas during July 2011. The between-pollutant Pearson correlations and Z-scores (calculated from log-transformed concentrations) between near-highways and non-highways and between near-urban centers and non-urban centers varied by pollutant pair and space. We found generally lower correlations between NO{sub x} and other pollutants for near-highways (average r = 0.36) than for non-highways (average r = 0.41) and also for non-urban centers (average r = 0.37) than for near-urban centers (average r = 0.41). This indicated that the temporal associations between NO{sub x} and health outcomes might be less affected by other pollutants, which were also related to same health outcomes, for near-highways and non-urban centers. The analysis of between-pollutant Z-scores showed varying spatial relations for popular traffic-related pollutants with the Z-score differences of 0.43 (NO{sub x}-carbon monoxide), 0.29 (NO{sub x}-black carbon), and 0.17 (black carbon-carbon monoxide) between near-highways and non-highways. This result exhibited heterogeneous traffic-related pollutant mixtures with the proximity to highways, potentially leading to the diverse extent of health associations. Furthermore, a mixed effects model presented pollutant-specific associations between the concentrations and the proximity to highways and urban centers, showing larger declines for NO{sub x}, xylenes/ethylbenzene, toluene, and NO{sub y} than those for the pollutants related to secondary pollutant formation. The model also demonstrated the different sensitivity of each pollutant to meteorological parameters, which may modify the spatial and temporal variability in the relations between the pollutants. Our findings provide insights for exposure assessment studies to better understand the cumulative health consequences associated with multiple air pollutants simultaneously.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Exposure to traffic-related air pollution and the composition of the gut microbiota in overweight and obese adolescents

Highlights: • Traffic-related air pollution (TRAP) was positively correlated with fasting glucose. • TRAP exposure was correlated with specific gut microbial taxa. • These taxa partially explained the correlation between TRAP and fasting glucose. • TRAP exposure may negatively impact metabolic health via the gut microbiota. Traffic-related air pollution (TRAP) exposure has been linked to type 2 diabetes and metabolic dysfunction in humans. Animal studies suggest that air pollutants may alter the composition of the gut microbiota, which may negatively impact metabolic health through changes in the composition and/or function of the gut microbiome.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Adverse pregnancy outcomes in women with changing patterns of exposure to the emissions of a municipal waste incinerator

Highlights: • Reproductive health outcomes are suitable for risk assessment of a waste incinerator. • Emissions from a municipal solid waste incinerator did not increase miscarriage rate. • Emissions from a municipal solid waste incinerator did not increase birth defects. Municipal solid waste incinerators emissions contain pollutants that, despite their low concentration, might adversely affect reproductive health. In the present study, we examined rates of miscarriage and birth defects among women who resided or were employed in the vicinity of a municipal solid waste incinerator plant from 2003 to 2013. In 2009, a progressive shutdown of the old incineration lines and operation of a new line caused considerably higher atmospheric release of polycyclic aromatic hydrocarbons, particularly of dioxins, due to these irregular operating conditions, technological renovation, and increased capacity. We used dioxin emission levels, based on a dispersion model, to define exposure status of the residing population to air pollutants emitted by the waste incinerator. In women who resided in areas characterized by higher emission exposures compared with a referent area, the relative risk (RR) of miscarriage was 1.04 (95% confidence interval (CI) 0.80–1.32) based on 62 cases overall, with little evidence of a dose-response relation. RRs were similarly null for both 2003–2008 and 2010–2013 periods (RR 1.12 (95% CI 0.80–1.53) and 0.98 (95% CI 0.63–1.48), respectively). Concerning birth defects in the offspring of women residing in the exposed area, no evidence of increased risk emerged, since the prevalence ratio at birth was 0.64 (95% CI 0.29–1.26), with comparable results in the 2003–2008 and 2010–2013 period. Corresponding analyses carried out in municipal residents who worked in the exposed area confirmed these findings. We also did not detect abnormally high rates of miscarriage and birth defects in the exposed cohorts in the single year 2009. Overall, these results do not suggest an effect of exposure to the emissions of the municipal solid waste incinerator we investigated on two indicators of reproductive health. However, the limited statistical stability of the estimates and the absence of individual-based information on some potential confounders suggest caution in the interpretation of study findings.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2016

Urine and serum biomonitoring of exposure to environmental estrogens II: Soy isoflavones and zearalenone in pregnant women

Urine and serum biomonitoring was used to measure internal exposure to selected dietary estrogens in a cohort of 30 pregnant women. Herein exposure was measured over a period comprising one-half day in the field (6 h) and one day in a clinic (24 h). Biomonitoring of the dietary phytoestrogens genistein (GEN), daidzein (DDZ) and equol (EQ), as well as the mycoestrogen, zearalenone (ZEN) and its congeners, was conducted using UPLC-MS/MS. Biomonitoring revealed evidence of internal exposure to naturally occurring dietary estrogens during pregnancy. Urinary concentrations of total GEN, DDZ and EQ were similar to levels reported for general adult U.S. population. Measurable concentrations of total (parent and metabolites) GEN, DDZ and EQ were present in 240, 207 and 2 of 270 serum samples, respectively. Six out of 30 subjects had measurable concentrations of unconjugated GEN and/or DDZ in serum between 0.6 and 7.1 nM. Urine to serum total isoflavone ratios for GEN, DDZ and EQ were 13, 47, and 180, respectively. ZEN and its reductive metabolite, a-zearalenol (a-ZEL), were present in pregnant women (11 out of 30 subjects) as conjugates at levels near the limit of quantification. The average total urinary concentration was 0.10 mg/L for ZEN and 0.11 mg/L for a-ZEL.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2023

Environmental exposure to industrial air pollution is associated with decreased male fertility

Objective: To understand how chronic exposure to industrial air pollution is associated with male fertility through semen parameters. Design: Retrospective cohort study. Subjects: Men in the Subfertility, Health and Assisted Reproduction cohort who underwent a semen analysis 2005-2017 with ≥1 measured semen parameter (N=21,563). Intervention(s): Residential histories for each man were constructed using locations from administrative records linked through the Utah Population Database. Industrial facilities with air emissions of nine endocrine disrupting compound chemical classes were identified from the Environmental Protection Agency Risk-Screening Environmental Indicators microdata. Chemical levels were linked with residential histories for the 5 years prior to each semen analysis. Main Outcome Measures: Semen analyses were classified as azoospermic or oligozoospermic (< 15 M/mL) using World Health Organization cutoffs for concentration. Bulk semen parameters such as concentration, total count, ejaculate volume, total motility, total motile count, and total progressive motile count were also measured. Multivariable regression models with robust standard errors were used to associate exposure quartiles for each of the nine chemical classes with each semen parameter, adjusting for age, race, and ethnicity, as well as neighborhood socioeconomic disadvantage. Results: After adjustment for demographic covariates, several chemical classes were associated with azoospermia and decreased total motility and volume. For exposure in the 4th relative to 1st quartile, significant associations were observed for acrylonitrile (β total motility = -0.87 pp), aromatic hydrocarbons (odds ratio [OR]azoospermia = 1.53; β volume = -0.14 mL), dioxins (OR azoospermia = 1.31; β volume = -0.09 mL; β total motility = -2.65 pp), heavy metals (β total motility = -2.78pp), organic solvents (OR azoospermia = 1.75; β volume = -0.10 mL), organochlorines (OR azoospermia = 2.09; β volume = -0.12 mL), phthalates (OR azoospermia = 1.44; β volume = -0.09 mL; β total motility = -1.21 pp), and silver particles (OR azoospermia = 1.64; β volume = -0.11 mL). All semen parameters significantly decreased with increasing socioeconomic disadvantage. Men who lived in the most disadvantaged areas had concentration, volume, and total motility of 6.70 M/mL, 0.13 mL, and 1.79 pp lower, respectively. Count, motile count, and total progressive motile count all decreased by 30–34 M.

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTAN↗
DOE OSTI2017

Attribution of PM 2.5 exposure in Beijing–Tianjin–Hebei region to emissions: implication to control strategies

The Beijing–Tianjin–Hebei (BTH) region is one of the most heavily polluted regions in China, with both high PM 2.5 concentrations and a high population density. A quantitative source-receptor relationship can provide valuable insights that can inform effective emission control strategies. Both source apportionment (SA) and source sensitivity (SS) can provide such information from different perspectives. In this study, both methods are applied in northern China to identify the most significant emission categories and source regions for PM 2.5 exposure in BTH in 2013. Despite their differences, both models show similar distribution patterns for population and simulated PM 2.5 concentrations, resulting in overall high PM 2.5 exposure values (approximately 110 μg/m 3 ) and particularly high exposure values during the winter (approximately 200 μg/m 3 ). Both methods show that local emissions play a dominant role (70%), with some contribution from surrounding provinces (e.g., Shandong) via regional transport. The two methods also agree on the priority of local emission controls: both identify industrial, residential, and agricultural emissions as the top three categories that should be controlled locally. In addition, the effect of controlling agricultural ammonia emissions is approximately doubled when the co-benefits of reducing nitrate are considered. In conclusion, the synthesis of SA and SS for addressing specific categories of emissions provides a quantitative basis for the development of emission control strategies and policies for controlling PM 2.5 in China.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗