ambient levels
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2022 ◽  
Author(s):  
Neha Raghava ◽  
Matthew Perkins ◽  
Graham Thomas

Abstract In light of the novel coronavirus and transmission in schools, increased scrutiny has been placed on airborne viral and particulate contamination, and efforts to mitigate this have been suggested, including the use of air purification. The importance of this is increased given the relationship between increased airborne particulates and increased coronavirus transmission, as well as the significance of removing particulates in the size range of bacteria and viruses from the air. Ambient levels of pm2.5 and pm1 in the absence of purification were recorded in two classrooms of similar size using medical grade data loggers, which then measured the change in these levels with use MedicAir air purifiers. It was found that baseline levels at times doubled the WHO limits for safe IAQ- MedicAir units were able to rapidly reduce levels of particulates to significantly below guidelines. We propose that the use of these units is an effective and rapid solution for the mitigation of coronavirus transmission, as well as the improvement of IAQ in schools.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
B. Blake Levitt ◽  
Henry C. Lai ◽  
Albert M. Manville

Abstract Due to the continuous rising ambient levels of nonionizing electromagnetic fields (EMFs) used in modern societies—primarily from wireless technologies—that have now become a ubiquitous biologically active environmental pollutant, a new vision on how to regulate such exposures for non-human species at the ecosystem level is needed. Government standards adopted for human exposures are examined for applicability to wildlife. Existing environmental laws, such as the National Environmental Policy Act and the Migratory Bird Treaty Act in the U.S. and others used in Canada and throughout Europe, should be strengthened and enforced. New laws should be written to accommodate the ever-increasing EMF exposures. Radiofrequency radiation exposure standards that have been adopted by worldwide agencies and governments warrant more stringent controls given the new and unusual signaling characteristics used in 5G technology. No such standards take wildlife into consideration. Many species of flora and fauna, because of distinctive physiologies, have been found sensitive to exogenous EMF in ways that surpass human reactivity. Such exposures may now be capable of affecting endogenous bioelectric states in some species. Numerous studies across all frequencies and taxa indicate that low-level EMF exposures have numerous adverse effects, including on orientation, migration, food finding, reproduction, mating, nest and den building, territorial maintenance, defense, vitality, longevity, and survivorship. Cyto- and geno-toxic effects have long been observed. It is time to recognize ambient EMF as a novel form of pollution and develop rules at regulatory agencies that designate air as ‘habitat’ so EMF can be regulated like other pollutants. Wildlife loss is often unseen and undocumented until tipping points are reached. A robust dialog regarding technology’s high-impact role in the nascent field of electroecology needs to commence. Long-term chronic low-level EMF exposure standards should be set accordingly for wildlife, including, but not limited to, the redesign of wireless devices, as well as infrastructure, in order to reduce the rising ambient levels (explored in Part 1). Possible environmental approaches are discussed. This is Part 3 of a three-part series.


2021 ◽  
Vol 193 (10) ◽  
Author(s):  
Susanna Lohman Haga ◽  
Annika Hagenbjörk ◽  
Anna-Carin Olin ◽  
Bertil Forsberg ◽  
Ingrid Liljelind ◽  
...  

AbstractExposure to air pollution is of great concern for public health although studies on the associations between exposure estimates and personal exposure are limited and somewhat inconsistent. The aim of this study was to quantify the associations between personal nitrogen oxides (NOx), ozone (O3) and particulate matter (PM10) exposure levels and ambient levels, and the impact of climate and time spent outdoors in two cities in Sweden. Subjects (n = 65) from two Swedish cities participated in the study. The study protocol included personal exposure measurements at three occasions, or waves. Personal exposure measurements were performed for NOx and O3 for 24 h and PM10 for 24 h, and the participants kept an activity diary. Stationary monitoring stations provided hourly data of NOx, O3 and PM, as well as data on air temperature and relative humidity. Data were analysed using mixed linear models with the subject-id as a random effect and stationary exposure and covariates as fixed effects. Personal exposure levels of NOx, O3 and PM10 were significantly associated with levels measured at air pollution monitoring stations. The associations persisted after adjusting for temperature, relative humidity, city and wave, but the modelled estimates were slightly attenuated from 2.4% (95% CI 1.8–2.9) to 2.0% (0.97–2.94%) for NOx, from 3.7% (95% CI 3.1–4.4) to 2.1% (95% CI 1.1–2.9%) for O3 and from 2.6% (95% 0.9–4.2%) to 1.3% (95% CI − 1.5–4.0) for PM10. After adding covariates, the degree of explanation offered by the model (coefficient of determination, or R2) did not change for NOx (0.64 to 0.63) but increased from 0.46 to 0.63 for O3, and from 0.38 to 0.43 for PM10. Personal exposure to NOx, O3 and PM has moderate to good association with levels measured at urban background sites. The results indicate that stationary measurements are valid as measure of exposure in environmental health risk assessments, especially if they can be refined using activity diaries and meteorological data. Approximately 50–70% of the variation of the personal exposure was explained by the stationary measurement, implying occurrence of misclassification in studies using more crude exposure metrics, potentially leading to underestimates of the effects of exposure to ambient air pollution.


Plants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1678
Author(s):  
María-Ángeles Del-Castillo-Alonso ◽  
Laura Monforte ◽  
Rafael Tomás-Las-Heras ◽  
Javier Martínez-Abaigar ◽  
Encarnación Núñez-Olivera

Ultraviolet (UV) radiation strongly influences grape composition, but only a few studies have focused on how this influence is conserved in the resulting wines. Here we analyzed to what extent the changes induced by exposing Tempranillo grapes to UV radiation from budbreak to harvest were conserved in wine. By using different cut-off filters and lamps, we differentiated the effects of ambient levels of UV-A and UV-B wavelengths, as well as the effects of a realistic UV-B enhancement associated with climate change. Among phenolic compounds, the most consistent responses to UV were those of flavonols (particularly quercetin-, kaempferol-, isorhamnetin- and myricetin-glycosides), which significantly increased in wines whose grapes had been exposed to a synergic combination of UV-A and UV-B radiation. This confirms that flavonols are the phenolic compounds most reliably conserved from UV-exposed grapes to wine, despite the possible influence of the winemaking process. Flavonols are important compounds because they contribute to wine co-pigmentation by stabilizing anthocyanins, and they are interesting antioxidants and nutraceuticals. Hydroxycinnamic acids also increased under the same UV combination or under UV-A alone. Wine VOCs were much less reactive to the UV received by grapes than phenolic compounds, and only esters showed significantly higher values under (mainly) UV-A alone. This was surprising because (1) UV-A has been considered to be less important than UV-B to induce metabolic changes in plants, and (2) esters are produced during winemaking. Esters are relevant due to their contribution to the fruity aroma in wines. In general, the remaining phenolic compounds (stilbenes, flavanols, hydroxybenzoic acids, and anthocyanins) and VOCs (alcohols, hydrocarbons, and fatty acids), together with wine color and antioxidant capacity, showed inconsistent or non-significant responses to UV radiation. These results were summarized by a multivariate analysis. Our study opens up new possibilities to artificially manipulate UV radiation in grapevine cultivation to improve both grape and wine quality.


Author(s):  
Madison McGough ◽  
Victoria L Pruente ◽  
William C Walton ◽  
Jessica L Jones

Desiccation is a routine farming practice utilized in off-bottom oyster aquaculture to reduce biofouling organisms and improve shell quality. This practice can increase Vibrio parahaemolyticus and V. vulnificus levels, leading to increased risk of illness for raw oyster consumers. Previous resubmersion studies were performed in geographic proximity to one another, so to better understand the broader applicability of resubmersion, the next step was to perform concurrent studies in multiple geographic locations within a region. This study evaluated the effect of variations in geographic location on the recovery time needed for elevated vibrio levels to return to ambient levels in desiccated oysters after resubmersion at Gulf Coast farms. Two trials were performed between May-August 2019 at sites spanning ~100 km: three in Alabama and one in Florida. Oysters were deployed in OysterGro cages at each location, two weeks prior to each trial, then either desiccated for 24 h or remained submersed as controls. Triplicate samples were taken prior to and immediately following the desiccation period, as well as 7 and 14 d post-resubmersion. Total and pathogenic ( tdh +/ trh +) V. parahaemolyticus , and V. vulnificus levels were determined using most probable number (MPN) real-time PCR. Vibrio levels increased by 0.23-3.50 log MPN/g after desiccation. Recovery times varied among geographic locations by trial and Vibrio spp., with all vibrio counts recovering to levels not significantly higher than those in control oysters within 7-14 days of resubmersion (p≥0.06). These results suggest a 14-day resubmersion period of cultured oysters allowed vibrio levels, elevated due to routine handling, to return to ambient levels at all farm sites studied.


2021 ◽  
pp. 79-90
Author(s):  
Michael Henderson ◽  
John Spillane ◽  
David Gyorki ◽  
Christopher McCormack

Throughout the world, each year, approximately 250,000 people develop melanoma and 40,000 die from the disease. Melanoma is characteristically a disease of fair-skinned persons exposed to high ambient levels of ultraviolet (UV) radiation. The incidence has doubled over the last 20 years although unlike other countries the rate of increase in Australia has slowed in recent years, possibly due to public education campaigns targeting excessive UV exposure. Globally the incidence in patients over the age of 65 continues to increase and accounts for disproportionately more melanoma-related deaths. Nevertheless, melanoma in younger persons (<35 years) is among the leading causes of cancer-related mortality in fair-skinned populations. Until the last decade, the outlook for patients with advanced melanoma was uniformly poor but the development of specific therapies targeting the mitogen-activated protein kinase pathway (mutated BRAF melanoma) and immune checkpoint therapy has delivered enormous improvements in outcome.


2021 ◽  
Vol 13 (3) ◽  
pp. 345-373
Author(s):  
Alex Hollingsworth ◽  
Ivan Rudik

Leaded gasoline is still used globally for aviation and automotive racing. Exploiting regulatory exemptions and a novel quasi-experiment, we find that leaded gasoline use in racing increases ambient lead, elevated blood lead rates, and elderly mortality. The mortality estimates indicate that each gram of lead added to gasoline exceeds $1,100 in damages. Our setting allows us to rule out potential confounders, such as correlated pollutants or socioeconomic status. We provide the first causal estimates linking adult mortality to leaded gasoline, highlight the value of banning on-road leaded gasoline, and present policy-relevant cost estimates at the lowest ambient levels to date. (JEL I12, J14, L71, Q51, Q53)


Atmosphere ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 947
Author(s):  
R. Burciaga Valdez ◽  
Mohammad Z. Al-Hamdan ◽  
Mohammad Tabatabai ◽  
Darryl B. Hood ◽  
Wansoo Im ◽  
...  

There is a well-documented association between ambient fine particulate matter air pollution (PM2.5) and cardiovascular disease (CVD) morbidity and mortality. Exposure to PM2.5 can cause premature death and harmful and chronic health effects such as heart attack, diabetes, and stroke. The Environmental Protection Agency sets annual PM2.5 standards to reduce these negative health effects. Currently above an annual average level of 12.0 µg/m is considered unhealthy. Methods. We examined the association of long-term exposure to PM2.5 and CVD in a cohort of 44,610 individuals who resided in 12 states recruited into the Southern Community Cohort Study (SCCS). The SCCS was designed to recruit Black and White participants who received care from Federally Qualified Health Centers; hence, they represent vulnerable individuals from low-income families across this vast region. This study tests whether SCCS participants who lived in locations exposed to elevated ambient levels of PM2.5 concentrations were more likely to report a history of CVD at enrollment (2002–2009). Remotely sensed satellite data integrated with ground monitoring data provide an assessment of the average annual PM2.5 in urban and rural locations where the SCCS participants resided. We used multilevel logistic regression to estimate the associations between self-reported CVD and exposure to elevated ambient levels of PM2.5. Results. We found a 13.4 percent increase in the odds of reported CVD with exposure to unhealthy levels of PM2.5 exposure at enrollment. The SCCS participants with medical histories of hypertension, hypercholesterolemia, and smoking had, overall, 385 percent higher odds of reported CVD than those without these clinical risk factors. Additionally, Black participants were more likely to live in locations with higher ambient PM2.5 concentrations and report high levels of clinical risk factors, thus, they may be at a greater future risk of CVD. Conclusions: In the SCCS participants, we found a strong relation between exposures to high ambient levels of PM2.5 and self-reported CVD at enrollment.


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