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At least 469 records · Page 26
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Temporal Trends of Racial and Socioeconomic Disparities in Population Exposures to Upstream Oil and Gas Development in California

People living near oil and gas development are exposed to multiple environmental stressors that pose health risks. Some studies suggest these risks are higher for racially and socioeconomically marginalized people, which may be partly attributable to disparities in exposures. We examined whether racially and socioeconomically marginalized people in California are disproportionately exposed to oil and gas wells and associated hazards. We longitudinally assessed exposure to wells during three time periods (2005–2009, 2010–2014, and 2015–2019) using sociodemographic data at the census block group‐level. For each block group and time period, we assessed exposure to new, active, retired, and plugged wells, and cumulative production volume. We calculated risk ratios to determine whether marginalized people disproportionately resided near wells (within 1 km). Averaged across the three time periods, we estimated that 1.1 million Californians (3.0%) lived within 1 km of active wells. Nearly 9 million Californians (22.9%) lived within 1 km of plugged wells. The proportion of Black residents near active wells was 42%–49% higher than the proportion of Black residents across California, and the proportion of Hispanic residents near active wells was 4%–13% higher than their statewide proportion. Disparities were greatest in areas with the highest oil and gas production, where the proportion of Black residents was 105%–139% higher than statewide. Socioeconomically marginalized residents also had disproportionately high exposure to wells. Though oil and gas production has declined in California, marginalized communities persistently had disproportionately high exposure to wells, potentially contributing to health disparities.

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTAN↗
DOE OSTI2023

Urban land patterns can moderate population exposures to climate extremes over the 21st century

Abstract Climate change and global urbanization have often been anticipated to increase future population exposure (frequency and intensity) to extreme weather over the coming decades. Here we examine how changes in urban land extent, population, and climate will respectively and collectively affect spatial patterns of future population exposures to climate extremes (including hot days, cold days, heavy rainfalls, and severe thunderstorm environments) across the continental U.S. at the end of the 21st century. Different from common impressions, we find that urban land patterns can sometimes reduce rather than increase population exposures to climate extremes, even heat extremes, and that spatial patterns instead of total quantities of urban land are more influential to population exposures. Our findings lead to preliminary suggestions for embedding long-term climate resilience in urban and regional land-use system designs, and strongly motivate searches for optimal spatial urban land patterns that can robustly moderate population exposures to climate extremes throughout the 21st century.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

Genetic background influences the effect of thirdhand smoke exposure on anxiety and memory in Collaborative Cross mice

Growing evidence indicates that thirdhand smoke (THS) exposure induces many adverse health effects. However, it is unclear how THS exposure affects behavior and how host genetic background modulates phenotypic changes. Here we used the Collaborative Cross (CC) mouse population-based model to assess behavioral alterations immediately after THS exposure from 4 to 9 weeks of age. We first measured anxiety-like behavior in six strains using light/dark box combined with a custom multivariate mouse tracking system. We developed an anxiety risk scoring system based on anxiety-related traits and then evaluated the THS impact on them. THS exposure significantly decreased anxiety risk in CC019 ( P = 0.002) and CC051 ( P = 0.009), but increased anxiety risk in CC036 ( P < 0.001), while the other three strains did not show significant changes in anxiety-related traits. Such differences were driven by female mice for the six measures of anxiety-like behavior. Memory potential was measured in the same cohort of mice using the passive avoidance assay. Both THS-exposed male and female CC019 mice displayed significant memory loss compared to controls while no significant changes were found in the other five strains. This study provides strong evidence that THS exposure leads to strain-dependent changes in anxiety-like behavior and memory, suggesting that host genetic variations play a critical role in individual susceptibility to THS-induced effects.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2016

Population exposure to hazardous air quality due to the 2015 fires in Equatorial Asia

Vegetation and peatland fires cause poor air quality and thousands of premature deaths across densely populated regions in Equatorial Asia. Strong El-Niño and positive Indian Ocean Dipole conditions are associated with an increase in the frequency and intensity of wildfires in Indonesia and Borneo, enhancing population exposure to hazardous concentrations of smoke and air pollutants. Here we investigate the impact on air quality and population exposure of wildfires in Equatorial Asia during Fall 2015, which were the largest over the past two decades. We performed high-resolution simulations using the Weather Research and Forecasting model with Chemistry based on a new fire emission product. The model captures the spatio-temporal variability of extreme pollution episodes relative to space- and ground-based observations and allows for identification of pollution sources and transport over Equatorial Asia. We calculate that high particulate matter concentrations from fires during Fall 2015 were responsible for persistent exposure of 69 million people to unhealthy air quality conditions. Short-term exposure to this pollution may have caused 11,880 (6,153–17,270) excess mortalities. Results from this research provide decision-relevant information to policy makers regarding the impact of land use changes and human driven deforestation on fire frequency and population exposure to degraded air quality.

Science & Technology - Other Topics↗
DOE OSTI2017

Impact of air exposure and surface chemistry on Li-Li 7 La 3 Zr 2 O 12 interfacial resistance

Li 7 La 3 Zr 2 O 12 (LLZO) is a promising solid-state electrolyte that could enable solid-state-batteries (SSB) employing metallic Li anodes. For a SSB to be viable, the stability and charge transfer kinetics at the Li–LLZO interface should foster facile plating and stripping of Li. Contrary to these goals, recent studies have reported high Li–LLZO interfacial resistance which was attributed to a contamination layer that forms upon exposure of LLZO to air. This study clarifies the mechanisms and consequences associated with air exposure of LLZO; additionally, strategies to minimize these effects are described. First-principles calculations reveal that LLZO readily reacts with humid air; the most favorable reaction pathway involves protonation of LLZO and formation of Li2CO3. X-ray photoelectron spectroscopy, scanning electron microscopy, Raman spectroscopy, and transmission electron microscopy were used to characterize the surface and subsurface chemistry of LLZO as a function of relative humidity and exposure time. Additionally, electrochemical impedance spectroscopy was used to measure the Li–LLZO interfacial resistance as a function of surface contamination. These data indicate that air exposure-induced contamination impacts the interfacial resistance significantly, when exposure time exceeds 24 h. The results of this study provide valuable insight into the sensitivity of LLZO to air and how the effects of air contamination can be reversed.

36 MATERIALS SCIENCE↗
DOE OSTI2011

Optimum exposure conditions for computed radiography depending on fixed pattern noise and efficiency of imaging plate-scanner systems

The presently active standards on Computed Radiography (CR) need a major revision. It was observed by many users that the image quality for class B of EN 14784-2 is not achievable under the same exposure conditions as used for film exposure. A mathematical model was developed and tested, which allows the calculation of the image quality, proven by image quality indicators (IQI), depending on the fixed pattern noise and the efficiency of the used imaging plate (IP) scanner system. All tested IP scanner systems provide a fixed correlation between the measured signal/noise ratio (SNR) and the grey values in the digital images. The maximum achievable SNR{sub max} depends on the fixed pattern noise of the plate (high dose limit). Depending on the exposure dose an optimum visibility of IQIs can be predicted by calculation and measured considering the attenuation coefficient for calculation of the contrast/noise ratio (CNR). The diameter of the just visible wire is proportional to 1/sqrt(CNR). The optimum tube voltage for best visibility of IQIs and maximum CNR depend on the exposure dose. The optimum tube voltage for best visibility is achieved only at exposures with high dose. A dose dependant optimal tube voltage was not observed for film radiography.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2014

An improved multi-exposure approach for high quality holographic femtosecond laser patterning

High efficiency two photon polymerization through single exposure via spatial light modulator (SLM) has been used to decrease the fabrication time and rapidly realize various micro/nanostructures, but the surface quality remains a big problem due to the speckle noise of optical intensity distribution at the defocused plane. Here, a multi-exposure approach which used tens of computer generate holograms successively loaded on SLM is presented to significantly improve the optical uniformity without losing efficiency. By applying multi-exposure, we found that the uniformity at the defocused plane was increased from ∼0.02 to ∼0.6 according to our simulation. The fabricated two series of letters “HELLO” and “USTC” under single-and multi-exposure in our experiment also verified that the surface quality was greatly improved. Moreover, by this method, several kinds of beam splitters with high quality, e.g., 2 × 2, 5 × 5 Daman, and complex nonseperate 5 × 5, gratings were fabricated with both of high quality and short time (<1 min, 95% time-saving). This multi-exposure SLM-two-photon polymerization method showed the promising prospect in rapidly fabricating and integrating various binary optical devices and their systems.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2018

Effect of laser intensity and exposure time on photothermal therapy with nanoparticles heated by a 793-nm diode laser and tissue optical clearing

Laser-induced thermotherapy is a promising method for cancer treatment, the outcome of which is affected by the exposure time. An inappropriate exposure time and laser intensity cause incomplete tumour destruction, tumour regrowth, and metastasis. Also possible is irreversible damage, i.e. death of healthy cells, and so numerical models are necessary to provide an optimised laser intensity and exposure time for different cancerous tumours. In this study, a model based on finite element method (FEM) is used for solving the bio-heat transfer equation and the Arrhenius equation describing tissue damage. The cancerous tumour is considered as a perfect cylinder with a diameter of 20 mm and a thickness of 2, 3, 4, and 5 mm, filled up by highly absorbing nanoparticles and surrounded by healthy cylindrical tissue with a diameter of 40 mm and a length of 10 mm, which ahs a low scattering coefficient due to optical clearing. The results show that 243 s is a safe and appropriate exposure time when a diode laser with a wavelength of 793 nm and intensity of 0.75 W cm{sup −2} together with gold nanorods of concentration 0.0001 % is used for the treatment of a 3-mm-thick tumour. Then, the results are developed and extensive numerical simulations are used to reveal mathematical relationships between two critical parameters, input power and optimised exposure time, for a series of different tumour thicknesses. Treatment protocols are presented.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2023

Computational Fluid Dynamics Simulations to Assess Spatial Variability and Optimal Ventilation Scenarios for Biological Laboratory Exposures

A significant amount of uncertainty exists regarding potential human exposure to laboratory biomaterials and organisms in Biosafety Level 2 (BSL-2) research laboratories. Computational fluid dynamics (CFD) modeling is proposed as a way to better understand potential impacts of different combinations of biomaterials, laboratory manipulations, and exposure routes on risks to laboratory workers. Here, in this study, we use CFD models to simulate airborne concentrations of contaminants in an actual BSL-2 laboratory under different configurations. Results show that ventilation configuration, sampling location, and contaminant source location can significantly impact airborne concentrations and exposures. Depending on the source location and airflow patterns, the transient and time-integrated concentrations varied by several orders of magnitude. Contaminant plumes from sources located near a return vent (or exhaust like a fume hood or ventilated biosafety cabinet) are likely to be more contained than sources that are further from the exhaust. Having a direct flow between the source and the exhaust (through-flow condition) may reduce potential exposures to individuals outside the air flow path. Designing a BSL-2 room with ventilation and airflow patterns that maximize through-flow conditions to the return/exhaust vents and minimize dispersion and mixing throughout the room is, therefore, recommended. CFD simulations can also be used to assist in characterizing the impacts of supply and return vent locations, room layout, and source locations on spatial and temporal contaminant concentrations. In addition, proper placement of particle sensors can also be informed by CFD simulations to provide additional characterization and monitoring of potential exposures in BSL-2 facilities.

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTAN↗
DOE OSTI2021

Declining carbohydrate content of Sitka-spruce treesdying from seawater exposure

Abstract Increasing sea levels associated with climate change threaten the survival of coastal forests, yet the mechanisms by which seawater exposure causes tree death remain poorly understood. Despite the potentially crucial role of nonstructural carbohydrate (NSC) reserves in tree survival, their dynamics in the process of death under seawater exposure are unknown. Here we monitored progressive tree mortality and associated NSC storage in Sitka-spruce (Picea sitchensis) trees dying under ecosystem-scale increases in seawater exposure in western Washington, USA. All trees exposed to seawater, because of monthly tidal intrusion, experienced declining crown foliage during the sampling period, and individuals with a lower percentage of live foliated crown (PLFC) died faster. Tree PLFC was strongly correlated with subsurface salinity and needle ion contents. Total NSC concentrations in trees declined remarkably with crown decline, and reached extremely low levels at tree death (2.4% and 1.6% in leaves and branches, respectively, and 0.4% in stems and roots). Starch in all tissues was almost completely consumed, while sugars remained at a homeostatic level in foliage. The decreasing NSC with closer proximity to death and near zero starch at death are evidences that carbon starvation occurred during Sitka-spruce mortality during seawater exposure. Our results highlight the importance of carbon storage as an indicator of tree mortality risks under seawater exposure.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2018

Correlation between Toluene Exposure and Toxicity Effects of Toluene on Drosophila Melanogaster Fecundity and Offspring Survivability

Toluene is a volatile organic compound that is a common indoor contaminant. According to the U.S. Department of Health and Human Services, chronic toluene exposure negatively affects organ systems, such as nervous and respiratory, and acts as a fetotoxic agent in the development of humans. Toluene exposure causes damage to human myelin sheaths, thus we propose that damage to the fly nervous system will be similar to that seen in humans exposed to toluene. Our ultimate goal is to determine the effects of toluene exposure on developmental and neuronal processes in D. melanogaster . In this first phase, we hypothesize that toluene‐exposed adults, at the interpolated Lethal Exposure (LE 50 ), will demonstrate decreased fecundity and that offspring from toluene‐exposed females will have decreased survivability from the egg to adult stage. We developed a continuous flow system that delivers known concentrations of gaseous toluene to populations of D. melanogaster . Ten to twenty adult female flies per trial were exposed for 24 hours to known concentrations of toluene. Surviving females were collected, counted and mated to non‐exposed adult males. The toluene‐exposed females were placed on a colored agar plate to lay eggs for 24 hours. Eggs were counted to determine fecundity (number of eggs produced by a single female fly). Survivability of eggs to later life stages, was measured by counting number of larvae, pupae, and adults divided by number eggs, larvae, and pupae respectively. The interpolated LE 50 of gaseous toluene was between 1000 and 1500 ppm after 24‐hour exposure. Fecundity of toluene‐exposed females decreased by approximately 50% when compared to airexposed females. The survivability of offspring of air‐exposed flies from egg to larval stages was 84% higher than published studies. We observed that larval eclosure from eggs laid by toluene‐exposed females was 35–50% higher on days 1 and 2 when compared to larval eclosure from eggs of air‐exposed exposed females. On days 3–6 the eclosure rate was relatively similar. These data showed toluene's effects on fecundity and survivability were measurable, however, additional replicates are in progress to fully assess the life table characteristics of offspring of toluene‐exposed female flies. Further studies will focus on toluene's effect on nervous and reproductive organs of fruit flies, along with a study on the mutagenic effects of toluene on fly DNA. Support or Funding Information U.S. DOE, Hispanic‐Serving Institutions, STEM Articulation Grant P031C110128 This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .

MacGregor, Michael Charles↗
DOE OSTI2019

Efficacy of Midazolam and Ketamine Combination Therapy over Midazolam Monotherapy against Soman Exposure in Carboxylesterase Knockout Mice

Introduction Chemical warfare nerve agents (CWNAs) inhibit acetylcholinesterase (AChE), which leads to status epilepticus (SE), spontaneous recurrent seizures (SRS) and severe neuropathology when treatment is delayed. In addition to binding to AChE, some organophosphorus (OP) CWNAs such as soman (GD) also inhibit carboxylesterase (CaE), which acts as a bioscavenger and can thus reduce the severity of the toxicity of OP agent exposure. Unlike humans, rodents have plasma CaE activity. The CaE knockout (ES1−/−) mouse specifically lacks plasma CaE and might better model human GD exposure compared to wildtype rodents. Delayed treatment of CWNA‐induced SE with midazolam leads to benzodiazepine‐refractory SE. We evaluated combination therapy of midazolam and the NMDA antagonist ketamine in male and female mice for efficacy against soman‐induced lethality, SE and epileptogenesis. Methods Mice implanted with telemetry transmitters for electroencephalography (EEG) seizure identification were exposed to 82 μg/kg GD (~4LD 50 ) and treated with an admix (ip) of atropine sulfate (4 mg/kg) and HI‐6 (50 mg/kg) 1 min after exposure, and with midazolam (3 mg/kg; ip) alone or in combination with ketamine (30 mg/kg, ip) at 40 min after seizure onset. Mice were continuously recorded to evaluate initial seizure duration and SRS and then euthanized 2 weeks after exposure for neuropathology assessment. Results Delayed treatment with midazolam resulted in poor survival, was unable to rapidly terminate behavioral or EEG seizure activity and did not prevent the development of SRS or neuronal loss following GD exposure. Combination therapy of midazolam and ketamine resulted in improved outcome, including an increase in survival from 30% to 78% in female and from 57% to 77% in males compared to midazolam monotherapy. In addition, the incidence of epileptogenesis was lower in mice treated with ketamine and midazolam dual therapy compared to midazolam monotherapy. Conclusions This study demonstrates that delayed treatment of SE with midazolam is not fully protective against the GD‐induced epileptogenesis and neuropathology, exemplifying the need for adjunct treatment to midazolam to prevent or reduce effects of GD‐induced SE. Ketamine combination with midazolam improves outcome. Support or Funding Information Research was supported by the CounterACT Program, NIH OD, and the NINDS (Grant 1R21NS103820‐01 to LA Lumley‐Lange) and by DTRA‐JSTO. Erica Kundrick, Katie Walker, and Sean O'Brien were supported in part by an appointment to the Research Participation Program for the U.S. Army Medical Research and Materiel Command administered by the Oak Ridge Institute for Science and Education through an agreement between the U.S. Department of Energy and U.S. Army Medical Research and Materiel Command. This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .

Marrero‐Rosado, Brenda↗
DOE OSTI2014

Joint US/Russian Studies of Population Exposures Resulting from Nuclear Production Activities in the Southern Urals

Beginning in 1948, the Soviet Union initiated a program for production of nuclear materials for a weapons program. The first facility for production of plutonium was constructed in the central portion of the country east of the southern Ural Mountains, about halfway between the major industrial cities of Ekaterinburg and Chelyabinsk. The facility now known as the Mayak Production Association and its associated town, now known as Ozersk, were built to irradiate uranium in reactors, separate the resulting plutonium in reprocessing plants, and prepare plutonium metal. The rush to production, coupled with inexperience in handling radioactive materials, lead to large radiation exposures, not only to the workers in the facilities, but also to the surrounding public. Fuel processing started with no controls on releases, and fuel dissolution and accidents in reactors resulted in release of about 37 PBq (1015 Bq) of 131I between 1948 and 1967. Designed disposals of low- and intermediate-level liquid radioactive wastes, and accidental releases via cooling water from tank farms of high-level liquid radioactive wastes, into the small Techa River caused significant contamination and exposures to residents of numerous small riverside villages downstream of the site. Discovery of the magnitude of the aquatic contamination in late 1951 caused revisions to the waste handling regimes, but not before over 200 PBq of radionuclides (with large contributions of 90Sr and 137Cs) were released. Liquid wastes were diverted to tiny Lake Karachay (which today holds over 4 EBq); cooling water was stopped in the tank farms. In 1957, one of the tanks in the tank farm overheated and exploded; over 70 PBq, disproportionately 90Sr, was blown over a large area to the northeast of the site; a large area was contaminated and many villages evacuated. This area today is known as the East Urals Radioactive Trace (EURT). Each of these releases was significant; together they have created a group of cohorts unrivaled in the world for their chronic, low-dose-rate radiation exposure. The 26,000 workers at Mayak were highly exposed to external gamma and inhaled plutonium. A cohort of individuals raised as children in Ozersk is under evaluation for their exposures to radioiodine. The Techa River Cohort consists of over 30,000 people who were born before the start of exposure in 1949 and lived along the Techa River. The Techa River Offspring Cohort consists of about 21,000 persons born to one or more exposed parents of this group - many of whom also lived along the contaminated river. The EURT Cohort consists of about 18,000 people who were evacuated from the EURT soon after the 1957 explosion and another 8000 who remained. These groups together are the focus of dose reconstruction and epidemiological studies funded by the US, Russia, and the European Union to address the question “Are doses delivered at low dose rates as effective in producing health effects as the same doses delivered at high dose rates?”

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTAN↗
DOE OSTI2014

SU-E-J-243: Possibility of Exposure Dose Reduction of Cone-Beam Computed Tomography in An Image Guided Patient Positioning System by Using Various Noise Suppression Filters

Purpose: To investigate the possibility of exposure dose reduction of the cone-beam computed tomography (CBCT) in an image guided patient positioning system by using 6 noise suppression filters. Methods: First, a reference dose (RD) and low-dose (LD)-CBCT (X-ray volume imaging system, Elekta Co.) images were acquired with a reference dose of 86.2 mGy (weighted CT dose index: CTDIw) and various low doses of 1.4 to 43.1 mGy, respectively. Second, an automated rigid registration for three axes was performed for estimating setup errors between a planning CT image and the LD-CBCT images, which were processed by 6 noise suppression filters, i.e., averaging filter (AF), median filter (MF), Gaussian filter (GF), bilateral filter (BF), edge preserving smoothing filter (EPF) and adaptive partial median filter (AMF). Third, residual errors representing the patient positioning accuracy were calculated as an Euclidean distance between the setup error vectors estimated using the LD-CBCT image and RD-CBCT image. Finally, the relationships between the residual error and CTDIw were obtained for 6 noise suppression filters, and then the CTDIw for LD-CBCT images processed by the noise suppression filters were measured at the same residual error, which was obtained with the RD-CBCT. This approach was applied to an anthropomorphic pelvic phantom and two cancer patients. Results: For the phantom, the exposure dose could be reduced from 61% (GF) to 78% (AMF) by applying the noise suppression filters to the CBCT images. The exposure dose in a prostate cancer case could be reduced from 8% (AF) to 61% (AMF), and the exposure dose in a lung cancer case could be reduced from 9% (AF) to 37% (AMF). Conclusion: Using noise suppression filters, particularly an adaptive partial median filter, could be feasible to decrease the additional exposure dose to patients in image guided patient positioning systems.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2015

Age at exposure and attained age variations of cancer risk in the Japanese A-bomb and radiotherapy cohorts

Purpose: Phenomenological risk models for radiation-induced cancer are frequently applied to estimate the risk of radiation-induced cancers at radiotherapy doses. Such models often include the effect modification, of the main risk to radiation dose response, by age at exposure and attained age. The aim of this paper is to compare the patterns in risk effect modification by age, between models obtained from the Japanese atomic-bomb (A-bomb) survivor data and models for cancer risks previously reported for radiotherapy patients. Patterns in risk effect modification by age from the epidemiological studies of radiotherapy patients were also used to refine and extend the risk effect modification by age obtained from the A-bomb survivor data, so that more universal models can be presented here. Methods: Simple log-linear and power functions of age for the risk effect modification applied in models of the A-bomb survivor data are compared to risks from epidemiological studies of second cancers after radiotherapy. These functions of age were also refined and fitted to radiotherapy risks. The resulting age models provide a refined and extended functional dependence of risk with age at exposure and attained age especially beyond 40 and 65 yr, respectively, and provide a better representation than the currently available simple age functions. Results: It was found that the A-bomb models predict risk similarly to the outcomes of testicular cancer survivors. The survivors of Hodgkin’s disease show steeper variations of risk with both age at exposure and attained age. The extended models predict solid cancer risk increase as a function of age at exposure beyond 40 yr and the risk decrease as a function of attained age beyond 65 yr better than the simple models. Conclusions: The standard functions for risk effect modification by age, based on the A-bomb survivor data, predict second cancer risk in radiotherapy patients for ages at exposure prior to 40 yr and attained ages before 55 yr reasonably well. However, for larger ages, the refined and extended models can be applied to predict the risk as a function of age.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2023

Policy-relevant differences between secondhand and thirdhand smoke: strengthening protections from involuntary exposure to tobacco smoke pollutants

Starting in the 1970s, individuals, businesses and the public have increasingly benefited from policies prohibiting smoking indoors, saving thousands of lives and billions of dollars in healthcare expenditures. Smokefree policies to protect against secondhand smoke exposure, however, do not fully protect the public from the persistent and toxic chemical residues from tobacco smoke (also known as thirdhand smoke) that linger in indoor environments for years after smoking stops. Nor do these policies address the economic costs that individuals, businesses and the public bear in their attempts to remediate this toxic residue. We discuss policy-relevant differences between secondhand smoke and thirdhand smoke exposure: persistent pollutant reservoirs, pollutant transport, routes of exposure, the time gap between initial cause and effect, and remediation and disposal. We examine four policy considerations to better protect the public from involuntary exposure to tobacco smoke pollutants from all sources. We call for (a) redefining smokefree as free of tobacco smoke pollutants from secondhandandthirdhand smoke; (b) eliminating exemptions to comprehensive smoking bans; (c) identifying indoor environments with significant thirdhand smoke reservoirs; and (d) remediating thirdhand smoke. We use the case of California as an example of how secondhand smoke-protective laws may be strengthened to encompass thirdhand smoke protections. The health risks and economic costs of thirdhand smoke require that smokefree policies, environmental protections, real estate and rental disclosure policies, tenant protections, and consumer protection laws be strengthened to ensure that the public is fully protected from and informed about the risks of thirdhand smoke exposure.

Public, Environmental & Occupational Health↗
DOE OSTI2013

Assessment of risk for asthma initiation and cancer and heart disease deaths among patrons and servers due to secondhand smoke exposure in restaurants and bars

Background: Despite efforts to reduce exposure to secondhand smoke (SHS), only 5% of the world’s population enjoy smoke-free restaurants and bars. Methods: Lifetime excess risk (LER) of cancer death, ischaemic heart disease (IHD) death and asthma initiation among non-smoking restaurant and bar servers and patrons in Minnesota and the US were estimated using weighted field measurements of SHS constituents in Minnesota, existing data on tobacco use and multiple dose-response models. Results: A continuous approach estimated a LER of lung cancer death (LCD) of 18×10 –6 (95% CI 13 to 23×10 –6 ) for patrons visiting only designated nonsmoking sections, 80×10 –6 (95% CI 66 to 95×10 –6 ) for patrons visiting only smoking venues/sections and 802×10 –6 (95% CI 658 to 936×10 –6 ) for servers in smoking-permitted venues. An attributable-risk (exposed/ non-exposed) approach estimated a similar LER of LCD, a LER of IHD death about 10 –2 for non-smokers with average SHS exposure from all sources and a LER of asthma initiation about 5% for servers with SHS exposure at work only. These risks correspond to 214 LCDs and 3001 IHD deaths among the general nonsmoking population and 1420 new asthma cases among non-smoking servers in the US each year due to SHS exposure in restaurants and bars alone. Conclusions: Health risks for patrons and servers from SHS exposure in restaurants and bars alone are well above the acceptable level. Restaurants and bars should be a priority for governments’ effort to create smoke-free environments and should not be exempt from smoking bans.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

Evaluation of Serial Testing After Exposure to COVID-19 in Early Care and Education Facilities, Illinois, March–May 2022

Objective: To understand SARS-CoV-2 transmission in early care and education (ECE) settings, we implemented a Test to Stay (TTS) strategy, which allowed children and staff who were close contacts to COVID-19 to remain in person if they agreed to test twice after exposure. We describe SARS-CoV-2 transmission, testing preferences, and the number of in-person days saved among participating ECE facilities. Methods: From March 21 through May 27, 2022, 32 ECE facilities in Illinois implemented TTS. Unvaccinated children and staff who were not up to date with COVID-19 vaccination could participate if exposed to COVID-19. Participants received 2 tests within 7 days after exposure and were given the option to test at home or at the ECE facility. Results: During the study period, 331 TTS participants were exposed to index cases (defined as people attending the ECE facility with a positive SARS-CoV-2 test result during the infectious period); 14 participants tested positive, resulting in a secondary attack rate of 4.2%. No tertiary cases (defined as a person with a positive SARS-CoV-2 test result within 10 days after exposure to a secondary case) occurred in the ECE facilities. Most participants (366 of 383; 95.6%) chose to test at home. Remaining in-person after an exposure to COVID-19 saved approximately 1915 in-person days among children and staff and approximately 1870 parent workdays. Conclusion: SARS-CoV-2 transmission rates were low in ECE facilities during the study period. Serial testing after COVID-19 exposure among children and staff at ECE facilities is a valuable strategy to allow children to remain in person and parents to avoid missing workdays.

Public, Environmental & Occupational Health↗