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.

Recycled polyvinyl chloride microplastics: investigation of environmentally relevant concentrations on toxicity in adult zebrafish.

Recycled polyvinyl chloride (PVC) microplastics have been detected in the aquatic environment. These recycled microparticles contain chemicals that are released into the environment reaching different organisms. Although the problem of the presence of recycled PVC microparticles in the environment is evident, the toxicological consequences of this contaminant to exposed organisms remains to be better determined. The aim of this study was to investigate the toxicity attributed to exposure to environmentally relevant concentrations of recycled PVC microplastics in adult zebrafish (Danio rerio). The experimental groups were: negative control, vehicle control, positive control, and recycled microplastics (20 ± 5 µm) at 5, 10 or 20 µg/L. Zebrafish (D. rerio) were exposed to respective treatments for 96 hr. Locomotion and oxidative status parameters were measured and mortality recorded. The positive control group presented increased mortality rates and decreased locomotor activity. Animals from the vehicle group did not show marked differences. Finally, no significant disturbances were found in survival rate, locomotion pattern and oxidative status of animals exposed to recycled PVC microparticles at 5, 10 or 20 µg/L. Taken together our results suggest that recycled PVC microplastics in this particle size range do not appear to exert harmful effects on exposed adult D. rerio. However, these results need to be carefully observed due to limitations including size of particle and duration of exposure parameters that might affect ecological consequences. It is suggested that additional studies applying other particles sizes and chronic exposure are needed to more comprehensively verify the toxicity of the contaminant investigated here.

Weekend effect of air pollutants in small and medium-sized cities: The role of policies stringency to COVID-19 containment.

Although the pattern of air pollutants has been extensively studied during the COVID-19 pandemic, the weekend effect has been rarely investigated. In order to understand the impact of policies stringency as well as the interruption-recovery pattern, the aim of the study was to investigate the levels of air pollutants (O3, NO2, SO2, PM2.5, PM10) and PM2.5/PM10 ratio before and after the COVID-19 pandemic in four cities in the state of Rio Grande do Sul, Brazil, evaluating the weekend effect at these two scenarios and also identifying how the restriction measures applied locally had an impact on this effect. For this, daily data from two years of monitoring of air pollutants were collected and the weekend effect was calculated based on the levels from Monday to Friday (weekday) and Saturday and Sunday (weekend). There was a positive weekend effect for almost all criteria air pollutants in the four cities, and an intrinsic relation between the weekend effect and the restriction measures adopted. A negative weekend effect was observed in the scenario characterized by less restrictive and more permissive policies for daily and occupational activities. Conversely, when more stringent measures were implemented, this trend was reversed and higher intensities of positive weekend effect were observed as restrictions increased. In conclusion, the COVID-19 perturbation to air quality changed as regions tighten and loosen restrictions on human mobility. These insights that can guide responsible authorities about future strategies and policies for air quality control.

Arsenite and arsenate toxicity in the earthworm Eisenia andrei (Bouché 1972) in natural soil and tropical artificial soil.

Inorganic forms of As (arsenite - As(III) and arsenate - As(V)) are prevalent in soil and recognized for their high toxicity. Once in the soil, these forms of As can compromise key organisms for ecological processes, such as earthworms. The aim of the study was to evaluate the toxicity of arsenite and arsenate in the Californian earthworm Eisenia andrei exposed in natural soil and tropical artificial soil (TAS). Adverse effects were evaluated using avoidance test, acute toxicity test, and a sublethal concentration test to assess biochemical parameters. LC50 values for arsenite were 21.27 mg/kg in natural soil and 19.0 mg/kg in TAS and for arsenate were 76.18 mg/kg in natural soil and above 120 mg/kg in TAS. In the avoidance test, this behavior was shown to be significantly higher in the natural soil and for earthworms exposed to arsenite, while total antioxidant capacity, glutathione levels, lipid damage, and DNA damage were significantly higher in animals exposed to arsenite, but without differences in relation to the two types of soil tested. Animals exposed to As(V) showed increased activity of enzymes related to glutathione metabolism. The results obtained in the present study show the impact of As exposure on the health of the Californian earthworm E. andrei, especially in the form of arsenite, and alert the public authorities that legal limits should, whenever possible, consider the soil properties and also the different chemical species of the contaminants.

Better understanding the behavior of air pollutants at shutdown times - results of a short full lockdown.

Numerous studies have evaluated the effects of lockdowns during the COVID-19 pandemic, but most of them have concerned large cities and regions. This study aimed to evaluate the dynamics of air pollutants during and after the implementation of a short lockdown in the medium-sized city of Pelotas, Brazil, using hourly measurements of pollutants. The evaluation period included in this study was between August 9th and 12th, 2020. A machine learning model was used to investigate the expected behavior against what was observed during the study period. All pollutants presented a gradual reduction until a dynamic plateau established 48 hours after the start of the lockdown: NO2 (↓4%), O3 (↓34%), SO2 (↓24%), CO (↓48%), PM10 (↓82%) and PM2.5 (↓82%). At the end of the restriction measures, the PM10 and PM2.5 levels continued to decline beyond expectations. Our findings show that these measures can positively affect the air quality in medium-sized cities.

Neurodevelopmental Outcomes among Brazilian Children with Cyanotic Congenital Heart Disease and Its Associated Factors.

Objectives: The aim of this study was to evaluate neurodevelopmental outcomes (motor development, nonverbal intelligence, and attention) in children with cyanotic congenital heart disease (CHD) compared with healthy children from a public hospital in southern Brazil. Materials and Methods: This was a cross-sectional study with pediatric patients of both sexes: 37 children with cyanotic CHD and a control group with 38 healthy children. Parents/guardians undertook a questionnaire and the SNAP IV scale (to evaluate attention) was applied. Two instruments were applied to each child: the R-2 Non-Verbal Intelligence test and the motor development scale. To assess the factors associated with insufficient performance in the three fields of neurodevelopment, a Poisson regression analysis was performed with a robust estimate. Results: There were no significant differences between children with cyanotic CHD and the control group for any of the neurodevelopmental outcomes studied. Low socioeconomic class was a factor associated with worse performance on the intelligence test and inattention. Furthermore, age was a factor for performance on the intelligence test, while a greater number of siblings was a factor associated with worse performance on the attention test. Conclusions: Public policies regarding child health must involve prioritizing the improvement of families' social conditions.

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, PM2.5) 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 PM2.5 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.

DNA damage in Brazilian newborns admitted to NICUs - association with maternal and neonatal outcomes.

Growing evidence suggests that early-life events can predispose the newborn to a variety of health problems in postnatal life, which can lead to the need for specialized care in the neonatal intensive care unit (NICU). These events may be caused by factors intrinsically related to the mother (i.e., lifestyle, socioeconomic conditions), and this interplay between maternal exposure factors and negative outcomes in the neonate can be efficiently monitored through effect biomarkers, such as DNA damage. Thus, the present study aimed to evaluate the DNA damage and the maternal and neonatal factors associated with the genotoxic outcome using newborns admitted to the NICUs of three hospitals located in the extreme south of Brazil. A total of 81 newborns were evaluated. DNA damage was assessed using the comet assay, and according to the result obtained for the evaluated parameters (tail length, % of tail DNA and tail moment). The investigation of associated factors was performed using the bivariate and multivariate Poisson regression analysis. As a result, we observed that the tail moment was the most sensitive parameter to detect differences between variables and genetic outcomes in newborns from NICU. Birthweight and the presence of respiratory diseases were associated with greater risks of DNA damage. Furthermore, the variables family income, sex, head circumference, preterm, birthweight and the presence of respiratory and/or infectious diseases showed a significant statistical difference regarding the groups with and without DNA damage (based on the median of the parameter). While the results of this study will serve as the basis for investigating genetic damage, we encourage that similar studies should be conducted elsewhere in order to confirm these and other outcomes as associated factors with DNA damage in newborns.

Health impacts of PM2.5-bound metals and PAHs in a medium-sized Brazilian city.

Rio Grande is a medium-sized industrial city located in the extreme south of Brazil, and previous studies in this city have shown contamination by metal(loids) and polycyclic aromatic hydrocarbons (PAHs) in water, soil, and sediment and in the atmosphere. In Brazil, the incorporation of PM2.5 monitoring in environmental legislation is recent (2018) and, like other developing countries, the number of studies is still small. This study aimed to investigate the levels of PM2.5 in the industrial and urban area of Rio Grande, to determine the concentration of metal(loid)s As, Cd, Cu, and Pb and of 16 PAHs in the samples of PM2.5, to perform the health risk assessment for these contaminants and the health impact assessment for two possible scenarios of reduction of PM2.5 levels. Our main findings regarding the PM2.5 samples include the following: (1) The levels of this pollutant in the city of Rio Grande were higher than those allowed in current Brazilian legislation, in both the industrial and urban areas; (2) the existence of non-carcinogenic and carcinogenic risks for metals present in all samples; (3) the absence of carcinogenic risk for the assessed PAHs; and (4) the reduction scenarios proposed pointed to a reduction of up to 22 deaths annually in conjunction with reductions in health-related expenditures. Thus, these results may serve as a basis for the development of public health policies aimed at improving air quality, jointly assisting health surveillance and directing future studies towards a better intrinsic approach to the problem.

Factors associated with genetic damage - an analysis integrating human populations from Southern Brazil.

Socioeconomic and demographic factors, lifestyle and cultural characteristics may play an important role in the development of genetic damage. This damage represents a potential health risk to an individual and increases the risk of developing negative outcomes. The aim of this study was to investigate the association of a set of factors and genetic damage by gathering data from previously studied populations in southern Brazil. This study analyzed data related to genetic damage and socioeconomic, demographic, and lifestyle variables of 514 individuals aged 18 to 64 years, residing in 8 cities located in the extreme south of the Brazil. A total of twelve factors were considered in the analysis, and of these seven had some association with the frequency of micronucleus or some parameter of the comet assay. Interestingly, age was a factor weakly associated with genetic damage, while skin color, occupational exposure, drug use, exposure to radiation, and the cultural habit of consuming chimarrão were shown to be associated with genetic damage when analyzed using multivariate regression. Therefore, we suggest that yerba mate consumption is a confounding factor and should be considered in cytogenetic studies in the southern region of South America. These results reinforce the need for human biomonitoring studies to include consideration of a broad range of population and cultural characteristics when seeking to identify relevant associations.

Unexpected reduction in ozone levels in a mid-size city during COVID-19 lockdown.

The current study evaluated ozone levels through passive samplers installed in 4 different points in a medium-sized city (Rio Grande, Brazil) with naturally low NO2 levels during a week of COVID-19 lockdown. Additionally, we evaluated the consequences of this response with regard to human health risk assessment and reduction of hospital admissions and ozone-related deaths. The reduction in ozone levels, one month after the implementation of containment measures, varied between 26 and 64% (average of 44%), in the different studied sites. The reduction of human mobility during the pandemic reduced the levels of ozone in Rio Grande city and consequently will bring benefits to health services in the municipality. This unexpected reduction in O3 levels must be related to the low 'natural' levels of NO2 in the city, which make the contribution of other precursors important for the fluctuation of O3 levels.

Watch out for trends: did ozone increased or decreased during the COVID-19 pandemic?

Restriction measures against COVID-19 caused the environmental panorama of cities to change, especially in relation to air pollution. This scenario of severe reduction in the emission of air pollutants led to a flurry of studies about their behavior during the pandemic. The vast majority of studies pointed to a decrease in all pollutants, with the exception of ozone. However, was this highlighted ozone trend really the global trend? This discussion seeks to answer this question while addressing two major considerations that led to this trend: (1) the process of ozone formation and behavior and (2) the main reasons that led to the findings of this trend (region of the studies, meteorological conditions, and the time scale adopted for data collection). From our observations, we emphasize that a trend is not unanimity! The global trend turned out to be the opposite of what the initial studies showed, all this because the observed trend was a regional trend, affected by the reasons discussed. Thus, we raise awareness and concern with the way in which the initial "fever" of the behavior of air pollutants occurred and also toward the act of sampling highly populated areas, as this attitude could have caused biased estimations and disinformation.

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.

Genetic damage in coal and uranium miners.

Mining has a direct impact on the environment and on the health of miners and is considered one of the most hazardous occupations worldwide. Miners are exposed to several occupational health risks, including genotoxic substances, which may cause adverse health effects, such as cancer. This review summarizes the relation between DNA damage and mining activities, focusing on coal and uranium miners. The search was performed using electronic databases, including original surveys reporting genetic damage in miners. Additionally, a temporal bibliometric analysis was performed using an electronic database to create a map of cooccurrence terms. The majority of studies were performed with regard to occupational exposure to coal, whereas genetic damage was assessed mainly through chromosomal aberrations (CAs), micronuclei (MNs) and comet assays. The bibliometric analysis demonstrated associations of coal exposure with silicosis and pneumoconiosis, uranium miners with lung cancer and tumors and some associated factors, such as age, smoking, working time and exposure to radiation. Significantly higher DNA damage in miners compared to nonexposed groups was observed in most of the studies. The timeline reveals that classic biomarkers (comet assay, micronucleus test and chromosomal aberrations) are still important tools to assess genotoxic/mutagenic damage in occupationally exposed miners; however, newer studies concerning genetic polymorphisms and epigenetic changes in miners are being conducted. A major challenge is to investigate further associations between miners and DNA damage and to encourage further studies with miners of other types of ores.

Oral cytological changes in young adults related to alcohol consumption.

OBJECTIVE: The study aimed to investigate the oral cytological changes in young adults with recent history of alcohol consumption, as well as its relation with the consumption of alcohol. DESIGN: The sample included 67 young adults, who performed a smear of the oral mucosa and answered a questionnaire about recent and lifetime consumption of alcohol and other drugs. The methods used were sensitive to show the association between alcohol consumption and other drugs with the damage to oral cavity cells. RESULTS: DNA fragmentation index, mitochondrial functionality and cell viability, showed a significant difference between alcohol users and nonusers. However, there was no distinction between these parameters and different frequency consumption. Alcohol consumption, economic class and use of illicit drugs were related to the cytological parameters evaluated. CONCLUSIONS: This result shows the existence of cell damages among the evaluated students and can direct future studies towards more in-depth investigations of the mechanisms involved.

Ecotoxicity of triclosan in soil: an approach using different species.

Triclosan is an antimicrobial agent widely used in personal care products and an emerging contaminant with potential to have harmful effects to edaphic organisms. This study aimed to evaluate the impacts of exposure to triclosan on the microbiota, plants, and edaphic animals using isolated bioassays and a microcosm scale representation (multispecies system). Among the isolated bioassays, the phytotoxicity test with Lactuca sativa, avoidance test with Eisenia andrei, and acute toxicity with E. andrei and Armadillidium vulgare were used. The multispecies system used seeds of L. sativa and Sinapis alba, together with earthworms and terrestrial isopods. This system also evaluated microbial activity through alkaline phosphatase and the metabolic profile using Ecoplate™, BIOLOG microplates. Exposure to triclosan impacted seedling growth in the isolated bioassay and germination and root growth in the microcosm scale assay; it also caused mortality in terrestrial isopods, earthworm avoidance and alteration of alkaline phosphatase, and the consumption profile of carbohydrates and carboxylic acids in the microbiota. The ecotoxicological effects evaluated in the multispecies system were perceived even in low concentrations of triclosan, indicating that the interaction of this xenobiotic with the environment and organisms in a more realistic scenario can compromise ecosystem services.

Bioassays for the evaluation of reclaimed opencast coal mining areas.

This study aimed to use bioassays (single and multispecies) with organisms from different trophic levels to assess soil quality in reclaimed coal mining areas. Soil samples were collected from four sites: two sites with recent reclaim processes (one using topsoil and other using clayey soil), an natural attenuation site, and a control soil. The evaluated parameters were divided into (1) ecotoxicological tests (avoidance test with Eisenia andrei (earthworms) and Armadillidium vulgare (isopods); germination test with Sinapis alba seeds (mustard); reproduction tests with Folsomia candida (collembolans); bacterial toxicity test); (2) population and community assessments (a fungal count; microbial community analysis using Biolog EcoPlatesTM); (3) microcosms scale evaluation (the MS-3 multispecies system); and (4) chemical analysis (soil parameters, soil metal, and cations and anions in soil leachate). Results pointed to toxicity in the natural attenuation site that compromised of habitat function, probably due to low pH and low nutrient levels. The most recent reclaim process, using topsoil and clay soil, improved soil quality and fertility, with a further increase in habitat quality and heterogeneity. This study shows that some techniques used to reclaim degraded mining areas are effective in rebuilding habitats, sustaining soil biota, and reestablishing ecosystem services.

In vivo toxicity evaluation of nanoemulsions for drug delivery.

Lipid nanocarriers (LNs), for example nanoemulsions (NE), are an emerging tool for drug delivery due to their ability to incorporate drugs, protect the drug from degradation, improve bioavailability, and control release. Although LNs are widely studied and applied, especially in the pharmaceutical field, knowledge about their toxicity is scarce. Moreover, the majority of studies focus on their efficiency rather than safety. Thus, the aim of this study was to evaluate the possible toxic effects of NE in vivo. Male Wistar rats (2 months old, 250 g) were treated once daily for 21 days with NE via oral or intraperitoneal delivery at 200, 400 or 800 mg lipid/kg body weight. At the end of the experiment, biochemical, hematological, oxidative stress, and genotoxicity parameters were analyzed. Our results showed that treatment with NE did not modify organ weight or biochemical parameters when compared to controls. The highest NE dose (800 mg/kg) via intraperitoneal injection caused changes in hematological parameters, namely increased plasma proteins, platelets, total leukocytes, and neutrophils, findings that suggest an inflammatory reaction. Further, the same dose evoked lipid peroxidation in the liver. Taken together, the results from this study suggest that NEs can be considered safe for oral administration, but high doses via the parenteral route can cause toxic effects. This study contributes to knowledge about NE toxicity and provides important data about their safe use in the pharmaceutical field.

Multimarker approach to assess the exposure of the wild rodent Calomys laucha to a simulated crude oil spill.

A mysterious oil spill occurred in the ocean near Brazil in 2019, which affected coastal areas in northeastern Brazil. When oil pollution occurs in coastal zones, organisms such as small mammals can suffer deleterious effects to their health. This study aimed to evaluate the effects of exposure to contaminated sandy soil with different crude oil concentrations in males of the species Calomys laucha. The exposure to crude oil resulted in multiple health issues for the subjects in the very first days of exposure. Furthermore, the exposure resulted in mutagenic damage to bone marrow blood cells and behavioral and morphological alterations, which were almost always in a dose-dependent form. The present study demonstrates the sensibility of the biomarkers used and highlights that small wild mammals such as C. laucha are useful for predicting environmental damage caused by the exposure to crude oil.