29 research outputs found
Racial Disparities in Air Pollution Burden and COVID-19 Deaths in Louisiana, USA, in the Context of Long-Term Changes in Fine Particulate Pollution
Black Americans in Louisiana are disproportionately dying from COVID-19, and environmental disparities may be contributing to this injustice. While Black communities in Louisiana\u27s industrialized regions (e.g., Cancer Alley, Calcasieu Parish) have been overburdened with pollution for decades, this disparity has not been evaluated by using recent data. Here, we explore statewide relationships among air pollution burden, race, COVID-19 death rates, and other health/socioeconomic factors. Measures of pollution burden included satellite-derived particulate matter (PM2.5) concentrations and health risks from toxic air pollution (i.e., respiratory hazard [RH] and immunological hazard [IH], estimated by the Environmental Protection Agency). In addition, we evaluate changes in emissions and ambient concentrations of fine PM(2.5)in Louisiana over the past few decades. Our overall goal was to better understand Louisiana\u27s burden of air pollution in the context of COVID-19. By all measures, a higher burden of air pollution was associated with larger percentages of Black residents and increased unemployment across Louisiana census tracts. Across parishes, higher COVID-19 death rates were associated with increased RH and IH and larger percentages of Black residents. These associations were not driven by diabetes, obesity, smoking, age, or poverty. Industrial sources comprised more of Louisiana\u27s PM(2.5)in 2017 versus 1990, as vehicle contributions declined 75% whereas industrial emissions remained about the same overall (despite variation in the interim). Ambient concentrations of PM(2.5)decreased statewide from 2000 to 2015, but subsequently increased in south Louisiana, concurrent with an upward trend in industrial emissions. Our findings highlight the critical need to address Louisiana\u27s pollution disparities and to recognize air pollution exposure as a risk factor for COVID-19
Racial Disparities in Air Pollution Burden and COVID-19 Deaths in Louisiana, USA, in the Context of Long-Term Changes in Fine Particulate Pollution
Black Americans in Louisiana are disproportionately dying from COVID-19, and environmental disparities may be contributing to this injustice. While Black communities in Louisiana\u27s industrialized regions (e.g., Cancer Alley, Calcasieu Parish) have been overburdened with pollution for decades, this disparity has not been evaluated by using recent data. Here, we explore statewide relationships among air pollution burden, race, COVID-19 death rates, and other health/socioeconomic factors. Measures of pollution burden included satellite-derived particulate matter (PM2.5) concentrations and health risks from toxic air pollution (i.e., respiratory hazard [RH] and immunological hazard [IH], estimated by the Environmental Protection Agency). In addition, we evaluate changes in emissions and ambient concentrations of fine PM2.5 in Louisiana over the past few decades. Our overall goal was to better understand Louisiana\u27s burden of air pollution in the context of COVID-19. By all measures, a higher burden of air pollution was associated with larger percentages of Black residents and increased unemployment across Louisiana census tracts. Across parishes, higher COVID-19 death rates were associated with increased RH and IH and larger percentages of Black residents. These associations were not driven by diabetes, obesity, smoking, age, or poverty. Industrial sources comprised more of Louisiana\u27s PM2.5 in 2017 versus 1990, as vehicle contributions declined 75% whereas industrial emissions remained about the same overall (despite variation in the interim). Ambient concentrations of PM2.5 decreased statewide from 2000 to 2015, but subsequently increased in south Louisiana, concurrent with an upward trend in industrial emissions. Our findings highlight the critical need to address Louisiana\u27s pollution disparities and to recognize air pollution exposure as a risk factor for COVID-19
Toxic air pollution and concentrated social deprivation are associated with low birthweight and preterm Birth in Louisiana
Previous studies indicate that pollution exposure can increase risks of adverse birth outcomes, but Black communities are underrepresented in this research, and the potential moderating role of neighborhood context has not been explored. These issues are especially relevant in Louisiana, which has a high proportion of Black residents, an entrenched history of structural racism, the most pounds of toxic industrial emissions annually, and among the nation’s highest rates of low birthweight (LBW), preterm birth (PTB), and infant mortality. We investigated whether air pollution and social polarization by race and income (measured via the index of concentration at the extremes [ICE]) were associated with LBW and PTB among Louisiana census tracts ( n = 1101) using spatial lag models. Data sources included 2011–2020 birth records, U.S. Census Bureau 2017 demographic data, and 2017 respiratory hazard (RH) from the U.S. Environmental Protection Agency. Both RH and ICE were associated with LBW ( z = 4.4, P < 0.0001; z = −27.0, P < 0.0001) and PTB ( z = 2.3, P = 0.019; z = −16.7, P < 0.0001), with no interaction. Severely polluted tracts had 25% higher and 36% higher risks of LBW and PTB, respectively, versus unpolluted tracts. On average, 2166 low birthweight and 3583 preterm births annually were attributable to pollution exposure. Tracts with concentrated social deprivation (i.e. low ICE scores) had 53% higher and 34% higher risks of LBW and PTB, respectively, versus intermediate or mixed tracts. On average, 1171 low birthweight and 1739 preterm births annually were attributable to concentrated deprivation. Our ecological study found that a majority of adverse birth outcomes in Louisiana (i.e. 67% of LBW and PTB combined) are linked to air pollution exposure or disadvantage resulting from social polarization. These findings can inform research, policy, and advocacy to improve health equity in marginalized communities
Pre- and postnatal effects of experimentally manipulated maternal corticosterone on growth, stress reactivity and survival of nestling house wrens
Corticosterone plays a central role in maintaining homeostasis, promoting energy acquisition, and regulating the stress response in birds. Exposure to elevated levels of corticosterone during development can profoundly alter offspring behaviour and physiology, but the effects of elevated maternal corticosterone on offspring development remain poorly understood. We tested two competing hypotheses concerning the effect of maternally derived corticosterone on growth and development of free-living house wrens: (i) elevated maternal corticosterone causes damaging effects on nestling phenotype and fitness (collateral damage hypothesis) and (ii) increased maternal corticosterone enhances offspring fitness by preparing nestlings for the environment experienced by their mother (environmental/maternal-matching hypothesis). We used a non-invasive means to increase maternal corticosterone by providing females with corticosterone-injected mealworms prior to and during egg production in the absence of any overt pre-natal maternal stress. To disentangle pre- and post-natal effects of this elevation in maternal corticosterone, we cross-fostered young in two experiments: (i) nestlings of control and experimental females were reared by unmanipulated, natural females in a uniform maternal environment; (ii) a split-brood design that enabled us to assess the interaction between the mother’s corticosterone treatment and that of the nestlings. There were significant pre-natal effects of increased maternal corticosterone on nestling growth and survival. Offspring of females experiencing experimentally increased corticosterone were heavier and larger than offspring of control females. There also was a significant interaction between maternal corticosterone treatment and the corticosterone treatment to which young were exposed within the egg in their effect on nestling survival while in the nest; experimental young exhibited greater survival than control young, but only when reared by control mothers. There was also a significant effect of maternal corticosterone treatment on nestling stress reactivity and, in both experiments, on the eventual recruitment of offspring as breeding adults in the local population. These patterns are broadly consistent with the environmental/maternal-matching hypothesis, and highlight the importance of disentangling pre- and post-natal effects of manipulations of maternal hormone levels on offspring phenotype. A plain language summary is available for this article
Data from: Pre- and post-natal effects of experimentally manipulated maternal corticosterone on growth, stress reactivity, and survival of nestling house wrens
1. Corticosterone plays a central role in maintaining homeostasis, promoting energy acquisition, and regulating the stress response in birds. Exposure to elevated levels of corticosterone during development can profoundly alter offspring behaviour and physiology, but the effects of elevated maternal corticosterone on offspring development remain poorly understood. 2. We tested two competing hypotheses concerning the effect of maternally derived corticosterone on growth and development of free-living house wrens: i) elevated maternal corticosterone causes damaging effects on nestling phenotype and fitness (collateral damage hypothesis) and (ii) increased maternal corticosterone enhances offspring fitness by preparing nestlings for the environment experienced by their mother (environmental/maternal-matching hypothesis). 3. We used a non-invasive means to increase maternal corticosterone by providing females with corticosterone-injected mealworms prior to and during egg production in the absence of any overt pre-natal maternal stress. To disentangle pre- and post-natal effects of this elevation in maternal corticosterone, we cross-fostered young in two experiments: i) nestlings of control and experimental females were reared by unmanipulated, natural females in a uniform maternal environment; ii) a split-brood design that enabled us to assess the interaction between the mother’s corticosterone treatment and that of the nestlings. 4. There were significant pre-natal effects of increased maternal corticosterone on nestling growth and survival. Offspring of females experiencing experimentally increased corticosterone were heavier and larger than offspring of control females. There also was a significant interaction between maternal corticosterone treatment and the corticosterone treatment to which young were exposed within the egg in their effect on nestling survival while in the nest; experimental young exhibited greater survival than control young, but only when reared by control mothers. There was also a significant effect of maternal corticosterone treatment on nestling stress reactivity and, in both experiments, on the eventual recruitment of offspring as breeding adults in the local population. 5. These patterns are broadly consistent with the environmental/maternal-matching hypothesis, and highlight the importance of disentangling pre- and post-natal effects of manipulations of maternal hormone levels on offspring phenotype
Continued Decline in Genetic Diversity Among Wild Cheetahs (Acinonyx jubatus) Without Further Loss of Semen Quality
As a well-studied felid with limited genetic diversity, the cheetah (Acinonyx jubatus) has shaped much of the scientific debate surrounding inbreeding depression. The species survived a population bottleneck ~ 12,000 years ago and was extirpated from \u3e 75% of its historical range in the last century. Modern cheetahs produce poor-quality semen, a presumed manifestation of inbreeding depression. Within Felidae, a positive association between genetic diversity and semen quality is well supported by pedigree data and inter-species comparisons. However, this relationship has never been examined among individual cheetahs. Furthermore, whether ongoing population declines are exacerbating inbreeding depression in wild or captive cheetah populations is unknown. Using 12 microsatellite markers, we evaluated the relationship between heterozygosity and reproductive traits among wild (n = 54) and captive (n = 43) male cheetahs born from 1976–2007. We tested the hypotheses that genetic diversity has declined over the last ~ 30 years and is positively correlated with semen quality/breeding success in the cheetah. Findings revealed that genetic diversity has decreased in the wild, but not captive, population. Unexpectedly, heterozygosity was lower in proven versus unproven breeders and did not correlate with semen quality. A small proportion of all males (\u3c 10%) produced relatively high quality ejaculates, with sperm traits similar to those of non-inbred felid species. These data suggest a more complex relationship between inbreeding and male cheetah reproductive traits than previously appreciated. Intensive management of captive cheetahs appears to be minimizing inbreeding, whereas the continued erosion of genetic diversity in wild males is of conservation concern
Pathogenic chytrid fungus Batrachochytrium dendrobatidis, but not B. salamandrivorans, detected on eastern hellbenders.
Recent worldwide declines and extinctions of amphibian populations have been attributed to chytridiomycosis, a disease caused by the pathogenic fungus Batrachochytrium dendrobatidis (Bd). Until recently, Bd was thought to be the only Batrachochytrium species that infects amphibians; however a newly described species, Batrachochytrium salamandrivorans (Bs), is linked to die-offs in European fire salamanders (Salamandra salamandra). Little is known about the distribution, host range, or origin of Bs. In this study, we surveyed populations of an aquatic salamander that is declining in the United States, the eastern hellbender (Cryptobranchus alleganiensis alleganiensis), for the presence of Bs and Bd. Skin swabs were collected from a total of 91 individuals in New York, Pennsylvania, Ohio, and Virginia, and tested for both pathogens using duplex qPCR. Bs was not detected in any samples, suggesting it was not present in these hellbender populations (0% prevalence, 95% confidence intervals of 0.0-0.04). Bd was found on 22 hellbenders (24% prevalence, 95% confidence intervals of 0.16 ≤ 0.24 ≤ 0.34), representing all four states. All positive samples had low loads of Bd zoospores (12.7 ± 4.9 S.E.M. genome equivalents) compared to other Bd susceptible species. More research is needed to determine the impact of Batrachochytrium infection on hellbender fitness and population viability. In particular, understanding how hellbenders limit Bd infection intensity in an aquatic environment may yield important insights for amphibian conservation. This study is among the first to evaluate the distribution of Bs in the United States, and is consistent with another, which failed to detect Bs in the U.S. Knowledge about the distribution, host-range, and origin of Bs may help control the spread of this pathogen, especially to regions of high salamander diversity, such as the eastern United States
Fecal androgen (A, C) and glucocorticoid (B, D) metabolite profiles of two randomly selected, representative male cheetahs on the basis of on- or off public exhibit (A, B) or number of care-givers (C, D).
<p>Fecal androgen (A, C) and glucocorticoid (B, D) metabolite profiles of two randomly selected, representative male cheetahs on the basis of on- or off public exhibit (A, B) or number of care-givers (C, D).</p
Mean (± SEM) seasonal ejaculate traits from cheetahs where semen was collected in different seasons at institutions throughout the USA (169 total ejaculates; number/season indicated in parentheses).
<p>There were no differences (<i>P</i> > 0.05) in any trait across seasons.</p