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101.
102.
Robyn L. Prueitt Heather N. Lynch Ke Zu Sonja N. Sax Ferdinand J. Venditti 《Critical reviews in toxicology》2014,44(9):791-822
We conducted a weight-of-evidence (WoE) analysis to assess whether the current body of research supports a causal relationship between long-term ozone exposure (defined by EPA as at least 30 days in duration) at ambient levels and cardiovascular (CV) effects. We used a novel WoE framework based on the United States Environmental Protection Agency's National Ambient Air Quality Standards causal framework for this analysis. Specifically, we critically evaluated and integrated the relevant epidemiology and experimental animal data and classified a causal determination based on categories proposed by the Institute of Medicine's 2008 report, Improving the Presumptive Disability Decision-making Process for Veterans. We found that the risks of CV effects are largely null across human and experimental animal studies. The few positive associations reported in studies of CV morbidity and mortality are very small in magnitude, mainly reported in single-pollutant models, and likely attributable to bias, chance, or confounding. The few positive effects in experimental animal studies were observed mainly in ex vivo studies at high exposures, and even the in vivo findings are not likely relevant to humans. The available data also do not support a biologically plausible mechanism for the effects of ozone on the CV system. Overall, the current WoE provides no convincing case for a causal relationship between long-term exposure to ambient ozone and adverse effects on the CV system in humans, but the limitations of the available studies preclude definitive conclusions regarding a lack of causation; thus, we categorize the strength of evidence for a causal relationship between long-term exposure to ozone and CV effects as “below equipoise.” 相似文献
103.
104.
Angel M. Dzhambov Donka D. Dimitrova 《International journal of occupational and environmental health》2017,23(3):215-221
Multiple risk factors for rheumatoid arthritis (RA) have been studied, but there is a dearth of research on occupational noise, which is highly prevalent in the United States (U.S.). This study aimed to determine whether occupational noise exposure was associated with an elevated risk of prevalent RA in the U.S. general population. Data from the 2011 to 2012 cross-sectional, population-based National Health and Nutrition Examination Survey were used for secondary analysis. Self-reported lifetime exposure to very loud noise was linked to self-reported doctor-diagnosed RA in a sample of 4192 participants. Weighted logistic regression was used to obtain nationally representative prevalence odds ratios (OR). The main and fully adjusted models yielded OR = 3.98 (95% CI: 1.74, 9.11) and OR = 2.84 (95% CI: 1.23, 6.57) for participants exposed for ≥ 15 years compared to never exposed participants. Excluding those diagnosed with RA more than five years before the interview, the effect dropped to OR = 3.67 (95% CI: 1.06, 12.75) in the main model, and was no longer significant in the fully adjusted model (OR = 2.68, 95% CI: 0.80, 8.96). The only significant effect modifier was race/ethnicity, with higher risk in Non-Hispanic whites. To conclude, long-term occupational noise exposure might be a modifiable risk factor for RA, but currently, the evidence base is very thin and tenuous. 相似文献
105.
院前急救是严重创伤救治链中非常重要的一环,也是创伤救治体系"三环理论"中的一个基本环节,是我国急救医疗服务体系中的重要组成部分,是提高严重创伤救治成功率、降低死亡率的根本保证。目前国内院前急救的模式还不统一,存在较多争议,但创伤院前急救的"快、准、稳"是院前急救工作者永远追求的目标。通过回顾文献、结合临床工作经历,就创伤院前急救中涉及的几个问题做一初步探讨,供同仁参考。 相似文献
106.
《International journal of hygiene and environmental health》2014,217(4-5):460-464
Epidemiological studies have shown associations between ambient air pollution and changes in heart rate variability (HRV). However, studies using personal air pollution measurements, especially with exposure averages <24 h, are still rare.Between February and March 2008 HRV data as well as personal exposure to particulate matter <2.5 μm (PM2.5), and particle number concentrations (PNC) were collected in five volunteers for up to 8.3 h on a 5 min resolution. Information about the participant's whereabouts was also collected. Mixed models were used to analyze concurrent and up to 30 min delayed effects of air pollutants as well as being in traffic on 5 min-averages of heart rate (HR), high and low frequency power (HF and LF), standard deviation of all normal-to-normal intervals (SDNN), and the root mean square of successive interval differences (RMSSD). Results are presented as %-change from the mean per increase in interquartile range of air pollutant.In total, 474 5-min segments were available for analysis. We observed concurrent and delayed reductions in SDNN of about 0.8–1.0% in association with a 5.4 μg/m3 increase in PM2.5. However, being in traffic by car led to an increase of about 20% 10–14 min and 15–19 min later. An increase in PM2.5 or PNC was associated with lagged decreases for RMSSD and HF. We detected concurrent reductions in RMSSD (−17.6% [95%-confidence interval: 29.1; −4.3]) when being in traffic by bike/foot. Being in traffic by car was associated with an immediate reduction in LF while more delayed increases in LF were observed when being in traffic by bike/foot. Air pollution and traffic effects on HR were less consistent.These rapid changes in HRV within 30 min might be mediated by the autonomic nervous system in response to direct reflexes from receptors in the lungs. 相似文献
107.
Julia F. Lippert Steven E. Lacey Rachael M. Jones 《Journal of occupational and environmental hygiene》2014,11(11):722-727
Exposure monitoring data indicate the potential for substantive exposure to laser-generated air contaminants (LGAC); however the diversity of medical lasers and their applications limit generalization from direct workplace monitoring. Emission rates of seven previously reported gas-phase constituents of medical laser-generated air contaminants (LGAC) were determined experimentally and used in a semi-empirical two-zone model to estimate a range of plausible occupational exposures to health care staff. Single-source emission rates were generated in an emission chamber as a one-compartment mass balance model at steady-state. Clinical facility parameters such as room size and ventilation rate were based on standard ventilation and environmental conditions required for a laser surgical facility in compliance with regulatory agencies. All input variables in the model including point source emission rates were varied over an appropriate distribution in a Monte Carlo simulation to generate a range of time-weighted average (TWA) concentrations in the near and far field zones of the room in a conservative approach inclusive of all contributing factors to inform future predictive models. The concentrations were assessed for risk and the highest values were shown to be at least three orders of magnitude lower than the relevant occupational exposure limits (OELs). Estimated values do not appear to present a significant exposure hazard within the conditions of our emission rate estimates. 相似文献
108.
Environmental Inequality in Exposures to Airborne Particulate Matter Components in the United States
Background: Growing evidence indicates that toxicity of fine particulate matter ≤ 2.5 μm in diameter (PM2.5) differs by chemical component. Exposure to components may differ by population.Objectives: We investigated whether exposures to PM2.5 components differ by race/ethnicity, age, and socioeconomic status (SES).Methods: Long-term exposures (2000 through 2006) were estimated for 215 U.S. census tracts for PM2.5 and for 14 PM2.5 components. Population-weighted exposures were combined to generate overall estimated exposures by race/ethnicity, education, poverty status, employment, age, and earnings. We compared population characteristics for tracts with and without PM2.5 component monitors.Results: Larger disparities in estimated exposures were observed for components than for PM2.5 total mass. For race/ethnicity, whites generally had the lowest exposures. Non-Hispanic blacks had higher exposures than did whites for 13 of the 14 components. Hispanics generally had the highest exposures (e.g., 152% higher than whites for chlorine, 94% higher for aluminum). Young persons (0–19 years of age) had levels as high as or higher than other ages for all exposures except sulfate. Persons with lower SES had higher estimated exposures, with some exceptions. For example, a 10% increase in the proportion unemployed was associated with a 20.0% increase in vanadium and an 18.3% increase in elemental carbon. Census tracts with monitors had more non-Hispanic blacks, lower education and earnings, and higher unemployment and poverty than did tracts without monitors.Conclusions: Exposures to PM2.5 components differed by race/ethnicity, age, and SES. If some components are more toxic than others, certain populations are likely to suffer higher health burdens. Demographics differed between populations covered and not covered by monitors. 相似文献
109.
Nina G. G. Domingo Srinidhi Balasubramanian Sumil K. Thakrar Michael A. Clark Peter J. Adams Julian D. Marshall Nicholas Z. Muller Spyros N. Pandis Stephen Polasky Allen L. Robinson Christopher W. Tessum David Tilman Peter Tschofen Jason D. Hill 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(20)
Agriculture is a major contributor to air pollution, the largest environmental risk factor for mortality in the United States and worldwide. It is largely unknown, however, how individual foods or entire diets affect human health via poor air quality. We show how food production negatively impacts human health by increasing atmospheric fine particulate matter (PM2.5), and we identify ways to reduce these negative impacts of agriculture. We quantify the air quality–related health damages attributable to 95 agricultural commodities and 67 final food products, which encompass >99% of agricultural production in the United States. Agricultural production in the United States results in 17,900 annual air quality–related deaths, 15,900 of which are from food production. Of those, 80% are attributable to animal-based foods, both directly from animal production and indirectly from growing animal feed. On-farm interventions can reduce PM2.5-related mortality by 50%, including improved livestock waste management and fertilizer application practices that reduce emissions of ammonia, a secondary PM2.5 precursor, and improved crop and animal production practices that reduce primary PM2.5 emissions from tillage, field burning, livestock dust, and machinery. Dietary shifts toward more plant-based foods that maintain protein intake and other nutritional needs could reduce agricultural air quality–related mortality by 68 to 83%. In sum, improved livestock and fertilization practices, and dietary shifts could greatly decrease the health impacts of agriculture caused by its contribution to reduced air quality.The health and environmental consequences of feeding the increasingly large and affluent global population are becoming increasingly apparent. These consequences have spurred interest in identifying food production practices and diets that improve human health and reduce environmental harm. Recent work has demonstrated that many of the opportunities for food producers and consumers to improve nutritional outcomes also have environmental benefits, such as reducing greenhouse gas emissions, land and water use, and eutrophication (1–6). It is largely unknown, however, how individual foods and diets affect air quality, even though air pollution is the largest environmental mortality risk factor in the United States and globally (7, 8), and agriculture is itself known to be a major contributor to reduced air quality (8, 9). In the United States alone, atmospheric fine particulate matter (PM2.5) from anthropogenic sources is responsible for about 100,000 premature deaths each year, one-fifth of which are linked to agriculture (10, 11).Here, we show how different foods affect human health by reducing air quality. We consider the emission of pollutants that contribute to atmospheric PM2.5, the chronic exposure to which increases the incidence of premature mortality from cardiovascular disease, cancer, and stroke (12, 13). These pollutants include directly emitted PM2.5 (primary PM2.5) and PM2.5 formed in the atmosphere (secondary PM2.5) from the precursors ammonia (NH3), nitrogen oxides (NOx), sulfur dioxide (SO2), and nonmethane volatile organic compounds (NMVOCs). From a spatially explicit inventory of emissions of primary PM2.5 and secondary PM2.5 precursors from agricultural supply chain activities for commodities in the contiguous United States (SI Appendix, Figs. S1 and S2) (14, 15) (Materials and Methods), we estimate increases in atmospheric concentrations of total (primary + secondary) PM2.5 attributable to agricultural emissions; total PM2.5 transport, chemistry, and removal; and exposure of populations to total PM2.5 using an ensemble of three independent air quality models (16–19). We describe damages attributable to 95 agricultural commodities and 67 final food products (full list in SI Appendix, Table S1), which cover >99% of US agricultural production (20). 相似文献
110.
John K. Kodros Dimitrios K. Papanastasiou Marco Paglione Mauro Masiol Stefania Squizzato Kalliopi Florou Ksakousti Skyllakou Christos Kaltsonoudis Athanasios Nenes Spyros N. Pandis 《Proceedings of the National Academy of Sciences of the United States of America》2020,117(52):33028
Oxidized organic aerosol (OOA) is a major component of ambient particulate matter, substantially impacting climate, human health, and ecosystems. OOA is readily produced in the presence of sunlight, and requires days of photooxidation to reach the levels observed in the atmosphere. High concentrations of OOA are thus expected in the summer; however, our current mechanistic understanding fails to explain elevated OOA during wintertime periods of low photochemical activity that coincide with periods of intense biomass burning. As a result, atmospheric models underpredict OOA concentrations by a factor of 3 to 5. Here we show that fresh emissions from biomass burning exposed to NO2 and O3 (precursors to the NO3 radical) rapidly form OOA in the laboratory over a few hours and without any sunlight. The extent of oxidation is sensitive to relative humidity. The resulting OOA chemical composition is consistent with the observed OOA in field studies in major urban areas. Additionally, this dark chemical processing leads to significant enhancements in secondary nitrate aerosol, of which 50 to 60% is estimated to be organic. Simulations that include this understanding of dark chemical processing show that over 70% of organic aerosol from biomass burning is substantially influenced by dark oxidation. This rapid and extensive dark oxidation elevates the importance of nocturnal chemistry and biomass burning as a global source of OOA.Highly oxidized organic aerosol (OOA) is a dominant component of particulate matter air pollution globally (1–3); however, sources of OOA remain uncertain, limiting the ability of models to accurately represent OOA and thus predict the associated climate, ecosystem, and health implications (4, 5). The current conceptual model of OOA formation suggests that anthropogenic OOA predominantly originates from the oxidation of volatile (VOCs), intermediate volatility (IVOCs), and semivolatile (SVOCs) organic compounds by the OH radical, resulting in lower-volatility products that condense to the particle phase (6). As the OH radical is formed through photolysis and has a very short atmospheric lifetime [less than a second (7)], this oxidation mechanism only occurs in the presence of sunlight. Further, the time scale for OOA formation through oxidation with OH in models is on the order of a few days (8). While this understanding is sufficient in explaining OOA concentrations in summer or periods with high solar radiation, atmospheric models fail to reproduce the observed concentration of OOA in the ambient atmosphere during winter and low-light conditions (9, 10). Fountoukis et al. (9) found simulated OOA concentrations significantly underestimated in wintertime Paris. Tsimpidi et al. (10) also reported an underprediction of simulated OOA globally in winter, suggesting missing sources of both primary OA (POA) and secondary formation pathways. This underproduction suggests a possible overlooked conversion pathway of organic vapors or particles to OOA that is not accounted for in current chemical transport and climate models.As stricter controls on fossil fuel combustion are implemented, residential biomass burning (BB) as a source of heating or cooking is becoming an increasingly important source of OA in urban environments (1, 11, 12). Further, increasing rates of wildfires from climate change are increasing the frequency of smoke-impacted days in urban areas (12–14). BB emissions include high concentrations of POA, SVOCs, IVOCs, and VOCs (15, 16), thus making BB a key source of OOA. Previous research has focused on quantifying the concentration of OOA formed through photochemical oxidation reactions (i.e., OH) with BB emissions (17, 18). However, oxidation of BB emissions in low or no sunlight is less well understood and is not included in chemical transport models. As opposed to OH, the NO3 radical is formed through reactions with NO2 and O3 and is rapidly lost in the presence of sunlight (19). Thus, the NO3 radical is only available in significant concentrations at night or other low-light conditions (20, 21). Previous research has established that biogenic VOCs may undergo oxidation at night when mixed with anthropogenic emissions containing NO2 and O3 (19, 22–27). There have been only a few studies that consider that nighttime oxidation of residential wood combustion may proceed through similar pathways (28–31); however, the magnitude and relevance to observed OOA in the ambient atmosphere has not yet been established. By combining laboratory experiments and ambient observations to inform a chemical transport model, we present strong evidence that nighttime oxidation of BB plumes (proceeding through reactions with O3 and the NO3 radical) is an important source of OOA. 相似文献