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At least 307 records · Page 17
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Exposure to environment chemicals and its possible role in endocrine disruption of children from a rural area

Highlights: • Rural children had elevated blood and hair Mn and Cr levels. • Disruption on thyroid function can be related to metals exposure in rural areas. • Dyslipidemia is associated to thyroid dysfunction in children exposed to metals. • Cholinesterase inhibitors insecticides affect the glucose homeostasis of children. • Children exposed to high levels of Mn can be evaluated through the prolactin. Endocrine disrupting chemicals (EDCs), including pesticides and metals, are present in rural areas, endangering the health of exposed populations. This work aimed to investigate the possible association between the exposure to these xenobiotics and thyroid dysfunction in children living in a rural community of Southern Brazil. Fifty-four children aged 5–16 years participated in this study. Peripheral biomarker evaluations were performed in periods of low and high exposure to pesticides. Thyroid ultrasonography was evaluated in the high exposure period. Blood levels of chromium (Cr), manganese (Mn), mercury (Hg), and lead (Pb), as well as hair Pb levels were positively correlated with thyroid stimulating hormone (TSH) concentrations and negatively associated with free thyroxine (fT4) levels in the low exposure period. Prolactin was positively associated with hair Mn in both periods. In the ultrasound tests, the majority of children presented a normal echogenicity of thyroid. Glucose was inversely associated with the biomarker of exposure to cholinesterase inhibitor insecticides, butyrylcholinesterase (BuChE). Lipid profile was above the recommended levels in both periods. In summary, our results show that children environmentally exposed to a mixture of xenobiotics in an agricultural community may have health impairments, especially on thyroid function, dyslipidemia, and glucose homeostasis disruption.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2013

Delayed myelosuppression with acute exposure to hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and environmental degradation product hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX) in rats

Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), a widely used munitions compound, and hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX), its N-nitroso product of anaerobic microbial nitroreduction, are contaminants of military sites. Previous studies have shown MNX to be the most acutely toxic among the nitroreduced degradation products of RDX and to cause mild anemia at high dose. The present study compares hematotoxicity with acute oral exposure to MNX with parent RDX. Both RDX and MNX caused a modest decrease in blood hemoglobin and ∼ 50% loss of granulocytes (NOAELs = 47 mg/kg) in female Sprague–Dawley rats observed 14 days post-exposure. We explored the possibility that blood cell loss observed after 14 days was delayed in onset because of toxicity to bone marrow (BM) progenitors. RDX and MNX decreased granulocyte/macrophage-colony forming cells (GM-CFCs) at 14, but not 7, days (NOAELs = 24 mg/kg). The earliest observed time at which MNX decreased GM-CFCs was 10 days post-exposure. RDX and MNX likewise decreased BM burst-forming units-erythroid (BFU-Es) at 14, but not 7, days. Granulocyte–erythrocyte–monocyte–megakaryocyte (GEMM)-CFCs were unaffected by RDX and MNX at 7 days suggesting precursor depletion did not account for GM-CFC and BFU-E loss. MNX added to the culture media was without effect on GM-CFC formation indicating no direct inhibition. Flow cytometry showed no differential loss of BM multilineage progenitors (Thy1.1{sup +}) or erythroid (CD71{sup +}) precursors with MNX suggesting myeloid and erythroid lineages were comparably affected. Collectively, these data indicate that acute exposure to both RDX and MNX caused delayed suppression of myelo- and erythropoiesis with subsequent decrease of peripheral granulocytes and erythrocytes. Highlights: ► Acute oral exposure to munitions RDX causes myelosuppression. ► Environmental degradation product MNX is comparable in effect. ► RDX and MNX are cytotoxic to both myeloid and erythroid progenitor cells. ► Myelosuppression is delayed in onset by > 7 days after single exposure.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2014

Persistent modification of Na{sub v}1.9 following chronic exposure to insecticides and pyridostigmine bromide

Many veterans of the 1991 Gulf War (GW) returned from that conflict with a widespread chronic pain affecting deep tissues. Recently, we have shown that a 60 day exposure to the insecticides permethrin, chlorpyrifos, and pyridostigmine bromide (NTPB) had little influence on nociceptor action potential forming Na{sub v}1.8, but increased K{sub v}7 mediated inhibitory currents 8 weeks after treatment. Using the same exposure regimen, we used whole cell patch methods to examine whether the influences of NTPB could be observed on Na{sub v}1.9 expressed in muscle and vascular nociceptors. During a 60 day exposure to NTPB, rats exhibited lowered muscle pain thresholds and increased rest periods, but these measures subsequently returned to normal levels. Eight and 12 weeks after treatments ceased, DRG neurons were excised from the sensory ganglia. Whole cell patch studies revealed little change in voltage dependent activation and deactivation of Na{sub v}1.9, but significant increases in the amplitude of Na{sub v}1.9 were observed 8 weeks after exposure. Cellular studies, at the 8 week delay, revealed that NTPB also significantly prolonged action potential duration and afterhyperpolarization (22 °C). Acute application of permethrin (10 μM) also increased the amplitude of Na{sub v}1.9 in skin, muscle and vascular nociceptors. In conclusion, chronic exposure to Gulf War agents produced long term changes in the amplitude of Na{sub v}1.9 expressed in muscle and vascular nociceptors. The reported increases in K{sub v}7 amplitude may have been an adaptive response to increased Na{sub v}1.9, and effectively suppressed behavioral pain measures in the post treatment period. Factors that alter the balance between Na{sub v}1.9 and K{sub v}7 could release spontaneous discharge and produce chronic deep tissue pain. - Highlights: • Rats were treated 60 days with permethrin, chlorpyrifos and pyridostigmine bromide. • 8 weeks after treatments, Nav1.9 activation and deactivation were unchanged. • The amplitude and conductance of Nav1.9 were increased 8 weeks following exposure. • Nociceptors exhibit increased action potential duration and afterhyperpolarization. • Acute permethrin altered activation physiology and increased the amplitude of Nav1.9.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2017

Heat wave exposure in India in current, 1.5 °C, and 2.0 °C worlds

Heatwaves with large impacts have increased in the recent past and will continue to increase under future warming. However, the implication for population exposure to severe heatwaves remains unexplored. Here, we characterize maximum potential human exposure (without passive/active reduction measures) to severe heatwaves in India. We show that if the global mean temperature is limited to 2.0 °C above pre-industrial conditions, the frequency of severe heatwaves will rise by 30 times the current climate by the end-21st century. In contrast, the frequency is projected to be about 2.5 times more (than the low-warming scenario of 2 °C) under conditions expected if the RCP8.5 'business-as-usual' emissions scenario is followed. Under the 2.0 °C low-warming target, population exposure to severe heatwaves is projected to increase by about 15 and 92 times the current level by the mid and end-21st century respectively. Strategies to reduce population growth in India during the 21st century may provide only limited mitigation of heatwave exposure mostly late in the century. Limiting global temperatures to 1.5 °C above preindustrial would reduce the exposure by half relative to RCP8.5 by the mid-21st century. If global temperatures are to exceed 1.5 °C then substantial measures will be required to offset the large increase in exposure to severe heatwaves in India.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Update on NREL Outdoor Exposure Campaign of Solar Mirrors

Beginning in 2018, the National Renewable Energy Laboratory restarted exposure campaigns on new and archived samples as part of a multiyear project, some with outdoor exposure for more than a decade. By resuming exposure and collecting and analyzing data on thousands of samples going back decades, several goals can be advanced that can be difficult to determine within the timeline of most projects: 1) correlating an accelerated exposure campaign to outdoor aging, specifically with xenon arc lamp exposure chambers; 2) drawing conclusions between specific corrosion mechanisms and weather patterns; and 3) finding novel relationships between mirror composition and performance. In addition to building and mining a database, we will experiment with new characterization techniques, primarily focused on macroscopic and microscopic imaging. In introducing these techniques more broadly, it may be possible to reveal a more direct line between optical performance and exposure campaigns by better understanding the degradation mechanisms occurring.

characterization techniques↗
DOE OSTI2015

Neonatal exposure of 17β-estradiol has no effects on mutagenicity of 7,12-dimethylbenz [a] anthracene in reproductive tissues of adult mice

Introduction: Biological studies in animals and epidemiological findings in humans clearly demonstrate that estrogens including 17β-estradiol (E2) are weak carcinogens via both genetic and epigenetic mechanisms. Carcinogenesis analyses have indicated that female mice exposed to E2 as neonates develop more mammary and ovarian tumors when compared to adult exposures. In the present study, Big Blue transgenic mice were used to investigate the effects of E2 on mutagenicity of 7,12-dimethylbenz [a] anthracene (DMBA), a genotoxic carcinogen, in mammary gland and ovary following neonatal exposure. Results: DMBA treatment resulted in significant increases in cII mutant frequencies (MFs) in both mammary glands and ovaries, with A:T → T:A transversion as the predominant type of mutation. However, co-exposure to E2 daily for the first 5 days after birth and to DMBA at 6 months of age did not significantly increase cII MFs compared to DMBA treatment alone. Further, there were also no significant differences in mutational spectra between DMBA exposure alone and E2 + DMBA treatment. Conclusion: These results suggest that early life exposures of mice to estrogens like E2 do not enhance mutagenicity by subsequent exposure to a chemical like DMBA in later life.

17 β-estradiol↗
NASA NTRS2000

Radiation exposure for human Mars exploration

One major obstacle to human space exploration is the possible limitations imposed by the adverse effects of long-term exposure to the space environment. Even before human space flight began, the potentially brief exposure of astronauts to the very intense random solar energetic particle events was of great concern. A new challenge appears in deep-space exploration from exposure to the low-intensity heavy-ion flux of the galactic cosmic rays since the missions are of long duration, and accumulated exposures can be high. Because cancer induction rates increase behind low to moderate thicknesses of aluminum shielding, according to available biological data on mammalian exposures to galactic cosmic ray-like ions, aluminum shield requirements for a Mars mission may be prohibitively expensive in terms of mission launch costs. Alternative materials for vehicle construction are under investigation to provide lightweight habitat structures with enhanced shielding properties. In the present paper, updated estimates for astronaut exposures on a Mars mission are presented and shielding properties of alternative materials are compared with aluminum.

NASA Center LaRC↗
NASA NTRS2021

Examining Runner’s Outdoor Heat Exposure Using Urban Microclimate Modeling and GPS Trajectory Mining

It is important to quantify human heat exposure in order to evaluate and mitigate the negative impacts of heat on human well-being in the context of global warming. This study proposed a human-centric framework to examine human personal heat exposure based on anonymous GPS trajectories data mining and urban microclimate modeling. The mean radiant temperature (Tmrt) that represents the human body’s energy balance was used to indicate human heat exposure. The meteorological data and high-resolution 3D urban model generated from multispectral remotely sensed images and LiDAR data were used as inputs in urban microclimate modeling to map the spatio-temporal distribution of the Tmrt in the Boston metropolitan area. The anonymous human GPS trajectory data collected from fitness Apps was used to map the spatiotemporal distribution of human outdoor activities. By overlaying the anonymous GPS trajectories on the generated spatio-temporal maps of Tmrt, this study further examined the heat exposure of runners in different age-gender groups in the Boston area. Results show that there is no significant difference in terms of heat exposure for female and male runners. The female runners in the age of 45-54 are exposed to more heat than female runners of 18-24 and 25-34, while there is no significant difference among male runners. This study proposed a novel method to estimate human heat exposure, which would shed new light on mitigating the negative impacts of heat on human health.

Personal heat exposure↗
DOE OSTI2013

Retrospective evaluation of exposure index (EI) values from plain radiographs reveals important considerations for quality improvement

Following X-ray exposure, radiographers receive immediate feedback on detector exposure in the form of the exposure index (EI). To identify whether radiographers are meeting manufacturer-recommended EI (MREI) ranges for routine chest, abdomen and pelvis X-ray examinations under a variety of conditions and to examine factors affecting the EI. Data on 5000 adult X-ray examinations including the following variables were collected: examination parameters, EI values, patient gender, date of birth, date and time of examination, grid usage and the presence of implant or prosthesis. Descriptive statistics were used to summarize each data set and the Mann–Whitney U test was used to determine significant differences, with P < 0.05 indicating significance for all tests. Most examinations demonstrated EI values that were outside the MREI ranges, with significantly higher median EI values recorded for female patient radiographs than those for male patients for all manufacturers, indicating higher detector exposures for all units except for Philips digital radiography (DR), where increased EI values indicate lower exposure (P = 0.01). Median EI values for out of hours radiography were also significantly higher compared with normal working hours for all technologies (P ≤ 0.02). Significantly higher median EI values were demonstrated for Philips DR chest X-rays without as compared to those with the employment of a grid (P = 0.03), while significantly lower median EI values were recorded for Carestream Health computed radiography (CR) chest X-rays when an implant or prosthesis was present (P = 0.02). Non-adherence to MREIs has been demonstrated with EI value discrepancies being dependent on patient gender, time/day of exposure, grid usage and the presence of an implant or prosthesis. Retrospective evaluation of EI databases is a valuable tool to assess the need of quality improvement in routine DR.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2016

Permeabilization of the nuclear envelope following nanosecond pulsed electric field exposure

Permeabilization of cell membranes occurs upon exposure to a threshold absorbed dose (AD) of nanosecond pulsed electric fields (nsPEF). The ultimate, physiological bioeffect of this exposure depends on the type of cultured cell and environment, indicating that cell-specific pathways and structures are stimulated. Here we investigate 10 and 600 ns duration PEF effects on Chinese hamster ovary (CHO) cell nuclei, where our hypothesis is that pulse disruption of the nuclear envelope membrane leads to observed cell death and decreased viability 24 h post-exposure. To observe short-term responses to nsPEF exposure, CHO cells have been stably transfected with two fluorescently-labeled proteins known to be sequestered for cellular chromosomal function within the nucleus – histone-2b (H2B) and proliferating cell nuclear antigen (PCNA). H2B remains associated with chromatin after nsPEF exposure, whereas PCNA leaks out of nuclei permeabilized by a threshold AD of 10 and 600 ns PEF. A downturn in 24 h viability, measured by MTT assay, is observed at the number of pulses required to induce permeabilization of the nucleus. - Highlights: • The ability of nsPEF to damage nuclear structures within cells is investigated. • Leakage of proliferating nuclear antigen from nuclei is induced by nsPEF. • High doses of nsPEF disrupt cortical lamin and cause chromatin decompaction. • Histone H2B remains attached to chromatin following nsPEF exposure. • DNA does not leak out of nsPEF-permeabilized nuclei.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2017

Cellular internalization, transcellular transport, and cellular effects of silver nanoparticles in polarized Caco-2 cells following apical or basolateral exposure

When considering the safety of ingested nanomaterials, it is important to quantitate their transfer across intestinal cells; however, little information exists about the effects of nanomaterial size or exposure side (apical versus basolateral epithelial surface) on nanomaterial transfer. Here, we examined cellular internalization and transcellular transport, and the effects of nanomaterials on Caco-2 monolayers after apical or basolateral exposure to Ag or Au nanoparticles with various sizes. After apical treatment, both internalization and transfer to the basolateral side of the monolayers were greater for smaller Ag nanoparticles than for larger Ag nanoparticles. In contrast, after basolateral treatment, larger Ag nanoparticles were more internalized than smaller Ag nanoparticles, but the transfer to the apical side was greater for smaller Ag nanoparticles. Au nanoparticles showed different rules of internalization and transcellular transport compared with Ag nanoparticles. Furthermore, the paracellular permeability of the Caco-2 monolayers was temporarily increased by Ag nanoparticles (5 μg/mL; diameters, ≤10 nm) following basolateral but not apical exposure. We conclude that the internalization, transfer, and effects of nanomaterials in epithelial cell monolayers depend on the size and composition of nanomaterials, and the exposure side. - Highlights: • Ag and Au nanoparticles can transfer across Caco-2 monolayers. • Cellular uptake of nanoparticles change between apical and basolateral exposure. • Basolateral Ag nanoparticle exposure increases the permeability of Caco-2 monolayers.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2011

Exposure to airborne metals and particulate matter and risk for youth adjudicated for criminal activity

Antisocial behavior is a product of multiple interacting sociohereditary variables, yet there is increasing evidence that metal exposure, particularly, manganese and lead, play a role in its epigenesis. Other metals, such as arsenic, cadmium, chromium, and mercury, and exposure to traffic-related air pollution, such as fine particulate matter ({<=}2.5 {mu}m) have been associated with neurological deficits, yet largely unexplored with respect to their relationship with delinquent behavior. The purpose of this study is to evaluate the ecological relationship between county-wide reported airborne emissions of air metals, particulate matter, and youth adjudicated for criminal activity. Metal exposure data were collected from the Environmental Protection Agency AirData. Population statistics were obtained from the United States Census 2000 and adjudication data was obtained from the Courts of Common Pleases from each Ohio County. Simple correlations were calculated with the percentage of adjudications, all covariates, and estimated metal air emissions. Separate negative binomial regression models for each pollutant were used to provide an estimated risk ratio of pollutant emissions on the risk of adjudication for all Ohio counties adjusting for urban-rural residence, percentage of African Americans, median family income, percentage of family below poverty, percentage of high school graduation in 25 years and older populations, and population density. Metal emissions and PM in 1999 were all correlated with adjudication rate (2003-2005 average). Metal emissions were associated with slightly higher risk of adjudication, with about 3-4% increased risk per natural log unit of metal emission except chromium. The associations achieved statistical significance for manganese and mercury. The particulate matter {<=}2.5 and {<=}10 {mu}m emissions had a higher risk estimate, with 12% and 19% increase per natural log unit emission, respectively, and also achieved statistical significance. In summary, airborne exposure to manganese, mercury, and particulate matter are associated with increased risk of adjudication. Causality cannot be proven in observational studies such as this one, but the association warrants further examination in other research studies. Comprehensive epidemiologic investigations of metal exposure in pediatric populations should include social health outcomes, including measures of delinquent or criminal activity. Furthermore, the influence of metals on the neurotoxic pathway leading to delinquent activity should be further explored. - Highlights: Black-Right-Pointing-Pointer We evaluate the relationship between air pollutants and adjudication. Black-Right-Pointing-Pointer Manganese, mercury, and particulate matter are associated with risk of adjudication. Black-Right-Pointing-Pointer Further research of metal exposure should include social health outcomes.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2012

Climate change and health: Indoor heat exposure in vulnerable populations

Introduction: Climate change is increasing the frequency of heat waves and hot weather in many urban environments. Older people are more vulnerable to heat exposure but spend most of their time indoors. Few published studies have addressed indoor heat exposure in residences occupied by an elderly population. The purpose of this study is to explore the relationship between outdoor and indoor temperatures in homes occupied by the elderly and determine other predictors of indoor temperature. Materials and methods: We collected hourly indoor temperature measurements of 30 different homes; outdoor temperature, dewpoint temperature, and solar radiation data during summer 2009 in Detroit, MI. We used mixed linear regression to model indoor temperatures' responsiveness to weather, housing and environmental characteristics, and evaluated our ability to predict indoor heat exposures based on outdoor conditions. Results: Average maximum indoor temperature for all locations was 34.85 Degree-Sign C, 13.8 Degree-Sign C higher than average maximum outdoor temperature. Indoor temperatures of single family homes constructed of vinyl paneling or wood siding were more sensitive than brick homes to outdoor temperature changes and internal heat gains. Outdoor temperature, solar radiation, and dewpoint temperature predicted 38% of the variability of indoor temperatures. Conclusions: Indoor exposures to heat in Detroit exceed the comfort range among elderly occupants, and can be predicted using outdoor temperatures, characteristics of the housing stock and surroundings to improve heat exposure assessment for epidemiological investigations. Weatherizing homes and modifying home surroundings could mitigate indoor heat exposure among the elderly.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2013

Lead, mercury, and cadmium exposure and attention deficit hyperactivity disorder in children

Background: There is limited research examining the relationship between lead (Pb) exposure and medically diagnosed attention deficit hyperactivity disorder (ADHD) in children. The role of mercury (Hg) and cadmium (Cd) exposures in ADHD development is even less clear. Objectives: To examine the relationship between Pb, Hg, and Cd and ADHD in children living inside and outside a Lead Investigation Area (LIA) of a former lead refinery in Omaha, NE. Methods: We carried out a case-control study with 71 currently medically diagnosed ADHD cases and 58 controls from a psychiatric clinic and a pediatric clinic inside and outside of the LIA. The participants were matched on age group (5–8, 9–12 years), sex, race (African American or Caucasians and others), and location (inside or outside LIA). We measured whole blood Pb, total Hg, and Cd using inductively coupled plasma mass spectrometry. Results: Inside the LIA, the 27 cases had blood Pb geometric mean (GM) 1.89 µg/dL and the 41 controls had 1.51 µg/dL. Outside the LIA, the 44 cases had blood Pb GM 1.02 µg/dL while the 17 controls had 0.97 µg/dL. After adjustment for matching variables and maternal smoking, socioeconomic status, and environmental tobacco exposure, each natural log unit blood Pb had an odds ratio of 2.52 with 95% confidence interval of 1.07–5.92. Stratification by the LIA indicated similar point estimate but wider CIs. No associations were observed for Hg or Cd. Conclusions: Postnatal Pb exposure may be associated with higher risk of clinical ADHD, but not the postnatal exposure to Hg or Cd. -- Highlights: • Blood Pb levels are associated with ADHD diagnosis in children. • No association was found between blood Cd or Hg levels and ADHD. • Children living close to hazardous waste site need to reduce metal exposure.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2014

Associations between cadmium exposure and circulating levels of sex hormones in postmenopausal women

Recent epidemiological as well as in vivo and in vitro studies collectively suggest that the metalloestrogen cadmium (Cd) could be a potential risk factor for hormone-related cancers in particularly breast cancer. Assessment of the association between Cd exposure and levels of endogenous sex hormones is of pivotal importance, as increased levels of such have been associated with a higher risk of breast cancer in postmenopausal women. The present study investigated the perceived relationship (multivariable-adjusted linear regression analyses) between Cd exposure [blood Cd (B-Cd) and urinary Cd (U-Cd)], and serum levels of androstenedione, testosterone, estradiol, and sex-hormone binding globulin (SHBG), in 438 postmenopausal Swedish women without hormone replacement therapy (HRT). A significant positive association between B-Cd (median 3.4 nmol/L) and serum testosterone levels, as well as a significant inverse association between B-Cd and serum estradiol levels and with the estradiol/testosterone ratio were encountered. However, U-Cd (median 0.69 nmol/mmol creatinine) was inversely associated with serum estradiol levels only. Our data may suggest that Cd interferes with the levels of testosterone and estradiol in postmenopausal women, which might have implications for breast cancer risk. - Highlights: • Low level cadmium exposure may interfere with the levels of steroid hormones. • Cadmium exposure was associated with increased serum testosterone concentrations. • Cadmium exposure was associated with decreased estradiol/testosterone ratio. • Cadmium exposure may have implications for breast-cancer promotion.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2015

Renal and blood pressure effects from environmental cadmium exposure in Thai children

Very few studies have shown renal and blood pressure effects from environmental cadmium exposure in children. This population study examined associations between urinary cadmium excretion, a good biomarker of long-term cadmium exposure, and renal dysfunctions and blood pressure in environmentally exposed Thai children. Renal functions including urinary excretion of β{sub 2}-microglobulin, calcium (early renal effects), and total protein (late renal effect), and blood pressure were measured in 594 primary school children. Of the children studied, 19.0% had urinary cadmium ≥1 μg/g creatinine. The prevalence of urinary cadmium ≥1 μg/g creatinine was significantly higher in girls and in those consuming rice grown in cadmium-contaminated areas. The geometric mean levels of urinary β{sub 2}-microglobulin, calcium, and total protein significantly increased with increasing tertiles of urinary cadmium. The analysis did not show increased blood pressure with increasing tertiles of urinary cadmium. After adjusting for age, sex, and blood lead levels, the analysis showed significant positive associations between urinary cadmium and urinary β{sub 2}-microglobulin and urinary calcium, but not urinary total protein nor blood pressure. Our findings provide evidence that environmental cadmium exposure can affect renal functions in children. A follow-up study is essential to assess the clinical significance and progress of renal effects in these children. - Highlights: • Few studies show renal effects from environmental cadmium exposure in children. • We report renal and blood pressure effects from cadmium exposure in Thai children. • Urinary β{sub 2}-microglobulin and calcium increased with increasing urinary cadmium. • The study found no association between urinary cadmium levels and blood pressure. • Environmental cadmium exposure can affect renal functions in children.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2016

Depleted and enriched uranium exposure quantified in former factory workers and local residents of NL Industries, Colonie, NY USA

Background: Between 1958 and 1982, NL Industries manufactured components of enriched (EU) and depleted uranium (DU) at a factory in Colonie NY, USA. More than 5 metric tons of DU was deposited as microscopic DU oxide particles on the plant site and surrounding residential community. A prior study involving a small number of individuals (n=23) indicated some residents were exposed to DU and former workers to both DU and EU, most probably through inhalation of aerosol particles. Objectives: Our aim was to measure total uranium [U] and the uranium isotope ratios: {sup 234}U/{sup 238}U; {sup 235}U/{sup 238}U; and {sup 236}U/{sup 238}U, in the urine of a cohort of former workers and nearby residents of the NLI factory, to characterize individual exposure to natural uranium (NU), DU, and EU more than 3 decades after production ceased. Methods: We conducted a biomonitoring study in a larger cohort of 32 former workers and 99 residents, who may have been exposed during its period of operation, by measuring Total U, NU, DU, and EU in urine using Sector Field Inductively Coupled Plasma - Mass Spectrometry (SF-ICP-MS). Results: Among workers, 84% were exposed to DU, 9% to EU and DU, and 6% to natural uranium (NU) only. For those exposed to DU, urinary isotopic and [U] compositions result from binary mixing of NU and the DU plant feedstock. Among residents, 8% show evidence of DU exposure, whereas none shows evidence of EU exposure. For residents, the [U] geometric mean is significantly below the value reported for NHANES. There is no significant difference in [U] between exposed and unexposed residents, suggesting that [U] alone is not a reliable indicator of exposure to DU in this group. Conclusions: Ninety four percent of workers tested showed evidence of exposure to DU, EU or both, and were still excreting DU and EU decades after leaving the workforce. The study demonstrates the advantage of measuring multiple isotopic ratios (e.g., {sup 236}U/{sup 238}U and {sup 235}U/{sup 238}U) over a single ratio ({sup 235}U/{sup 238}U) in determining sources of uranium exposure. - Highlights: • Biomonitoring study of residents and former workers exposed to DU in Colonie NY. • Urine (99 residents+32 former workers) analyzed for depleted uranium (DU). • DU detected in 84% of workers and 8% of residents >30 years after plant closed. • Enriched uranium detected in 6% of former workers based on isotope ratios.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2017

Exposure to lead in South African shooting ranges

Introduction: Lead exposure in shooting ranges has been under scrutiny for decades, but no information in this regard is available in respect of African settings, and in South Africa specifically. The aim of this study was to determine the blood lead levels in the users of randomly selected private shooting ranges in South Africa's Gauteng province. Methods: An analytical cross sectional study was conducted, with participants recruited from four randomly selected shooting ranges and three archery ranges as a comparator group. Results: A total of 118 (87 shooters and 31 archers) were included in the analysis. Shooters had significantly higher blood lead levels (BLL) compared to archers with 36/85 (42.4%) of shooters versus 2/34 (5.9%) of archers found to have a BLL ≥10 μg/dl (p<0.001). Conclusion: Shooting ranges may constitute an import site of elevated exposure to lead. Improved ventilation, low levels of awareness of lead hazards, poor housekeeping, and inadequate personal hygiene facilities and practices at South African shooting ranges need urgent attention. - Highlights: • This is the first study, to our knowledge, of lead exposure in shooting ranges in an African setting. • This study indicates highly elevated lead exposure amongst the users of certain private shooting ranges in South Africa. • Lead exposure may be a serious, yet under-studied, source of adult lead exposure in South Africa, and possibly elsewhere on the African continent.

54 ENVIRONMENTAL SCIENCES↗