Bioaccumulation of metals in Spartina alterniflora salt marshes in the estuary of the World's Largest Choked Lagoon

Salt marshes are capable of mitigating metal pollution in coastal environments, yet the efficacy of this remediation is contingent upon various environmental factors and the plant species involved. This study investigates the influence of different anthropogenic activities, including industrial, urban, recreational (in an insular area), and dredging operations, on the bioaccumulation of eight metals (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) within Spartina alterniflora Loisel. in the Patos Lagoon estuary, Brazil. The research aims to assess the pattern of metal bioaccumulation and distribution within the plant's leaves, stems, and roots while also examining metal presence in the sediment. Our main findings reveal that S. alterniflora exhibited elevated metal levels in its plant structure directly related with the metal concentrations in the surrounding sediment, which, in turn, is related to the different anthropogenic activities. The industrial area presented the highest metal levels in sediment and plant sections, followed by dredging, insular, and urban areas. This same pattern was mirrored for the bioconcetration factors (BCF), with the BCFs consistently indicating active metal bioaccumulation across all areas and for most of the metals. This provides evidence of the metal bioaccumulation pattern in S. alterniflora, with elevated BCFs in areas affected by activities with a higher degree of impact. Translocation factors (TF) showed varying metal mobility patterns within the plant's below-ground and above-ground sections across the different areas, with only Hg exhibiting consistent translocation across all study areas. Zn was the primary metal contributor in all plant sections, followed by Pb and Cu. It is worth noting that Pb is a non-essential metal for this plant, highlighting the relationship between elevated Pb contributions in the plant sections and the bioaccumulation of this metal within the plant's structure. Overall, this study emphasizes the bioaccumulation capacity of S. alterniflora and elucidate the intrinsic connection between different anthropogenic activities and their impact on the resultant availability and bioaccumulation of metals by this salt marsh plant.

Ethnic/Racial Disparity in Mortality from COVID-19: Data for the Year 2020 in Brazil

The study aimed to investigate ethnic/racial disparities in COVID-19 mortality in Brazilian federative units and their respective capitals in 2020. Population data and number of COVID-19 deaths were extracted by skin color (white, black, brown and indigenous) from all Brazilian states and their respective capitals. The mortality rate of COVID-19 by ethnicity in Brazilian states was higher between people from brown skin color, followed by indigenous and black. Only in one state, in the Federal District and in the federal capital, age-standardized mortality rates were higher among white's people. There is a high percentage of deaths from COVID-19 higher than expected among non-white individuals, especially in south-central states and capitals of the country. Mortality from COVID-19 affect ethnic-racial groups unevenly in Brazil and the number of excess deaths among non-whites was over 9000. Urgent government measures are needed to reduce the racial disparity in health indicators in Brazil.

Weekend effect on air pollutant levels in southernmost cities of Brazil with different economic activities

In view of the current premises of the need to investigate air pollution in small- and medium-sized cities, combined with concerns regarding the weekly behavior of air pollutants, this study aimed to investigate the weekly pattern of air pollution (O₃, NO₂, SO₂, PM_2.5) and the weekend effect in 4 Brazilian cities with different main economic activities. Our main findings include (1) positive weekend effect for all the assessed air pollutants in the four cities; therefore, in the southernmost region of Brazil, there was an increase in the concentration of air pollutants during weekends when compared to weekdays; (2) the highest levels of NO₂ and SO₂ were observed in the city characterized by the economic activity revolving around coal mining and generation of electricity through the burning of this mineraloid in a coal-fired power plant, while the highest levels of PM_2.5 were in the city with economic activity linked to industries, due to its recognized industrial complex; and (3) the seasonal evaluation of the weekend effect showed different behaviors for the air pollutants in each location, which is related to the set of meteorological conditions, economic activities, and population mobility in each location. In conclusion, our results demonstrate the aspects of pollution between cities and highlight that the comprehensive understanding of the weekend effect and its intricacies allows the responsible personal and government authorities to gain deep insights into the true effectiveness of future control strategies and the development of possible action plans.

Human health risk assessment of metals and anions in surface water from a mineral coal region in Brazil

Coal mining releases high concentration elements to the environment, which can be deposited in surface water, causing several human health problems. Candiota mine in the south of Brazil is the largest coal reserves in the country, representing approximately 40% of total national coal reserves. Therefore, the present study aimed to estimate the chronic daily dose and the non-carcinogenic risk index for metals and anions in surface waters of Candiota Region, using the USEPA protocols for Human Health Risk Assessment. A total of eight water samples were collected over a distance of up to 15 km from the emission sources of the thermal power generation companies, then the Chronic Daily Intake (CDI), Hazard Quotient (HQ), Hazard Index (HI), and sum of Hazard Index (ΣHI) were calculated. All the elements and anions evaluated showed natural concentrations for continental fresh waters according to Brazilian legislation, except Pb. Individually, none of the metals Pb, As, Cd, Ni, and Se or anions F^- and NO₃^- showed an HI value greater than 1. However, the sum of HI (ΣHI) (five metals and two anions) by sample point showed values close to 1, for one of the eight points analyzed. Pb and Fe were the elements that most contribute to the risk values in the sample points of the study area. Although, there is no human health risk in this scenario, this investigation highlight priority elements to future investigations in coal mine areas. In the current region, Pb and F^- as priority elements for future studies.