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1.
Environ Geochem Health ; 46(6): 209, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38814487

RESUMO

A comprehensive understanding of water quality is essential for assessing the complex relationship between surface water and sources of pollution. Primarily, surface water pollution is linked to human and animal waste discharges. This study aimed to investigate the physico-chemical characteristics of drinking water under both dry and wet conditions, assess the extent of bacterial contamination in samples collected from various locations in District Shangla, and evaluate potential health risks associated with consuming contaminated water within local communities. For this purpose, 120 groundwater and surface water samples were randomly collected from various sources such as storage tanks, user sites, streams, ponds and rivers in the study area. The results revealed that in Bisham, lakes had the highest fecal coliform levels among seven tested sources, followed by protected wells, reservoirs, downstream sources, springs, rivers, and ditches; while in Alpuri, nearly 80% of samples from five sources contained fecal coliform bacteria. Similarly, it was observed that the turbidity level, total dissolved solids, electrical conductivity, biological oxygen demand, and dissolved oxygen in the surface drinking water sources of Bisham were significantly higher than those in the surface drinking water sources of Alpuri. Furthermore, the results showed that in the Alpuri region, 14% of the population suffers from dysentery, 27% from diarrhea, 22% from cholera, 13% from hepatitis A, and 16% and 8% from typhoid and kidney problems, respectively, while in the Bisham area, 24% of residents are affected by diarrhea, 17% by cholera and typhoid, 15% by hepatitis A, 14% by dysentery, and 13% by kidney problems. These findings underscore the urgent need for improved water quality management practices and public health interventions to mitigate the risks associated with contaminated drinking water. It is recommended to implement regular water quality monitoring programs, enhance sanitation infrastructure, and raise awareness among local communities about the importance of safe drinking water practices to safeguard public health.


Assuntos
Água Potável , Microbiologia da Água , Qualidade da Água , Paquistão , Água Potável/microbiologia , Água Potável/química , Humanos , Monitoramento Ambiental/métodos , Água Subterrânea/microbiologia , Água Subterrânea/química , Fezes/microbiologia , Bactérias/isolamento & purificação
2.
Artigo em Inglês | MEDLINE | ID: mdl-38522509

RESUMO

BACKGROUND: Psychiatric illness during pregnancy is associated with adverse obstetric outcomes, but investigations into its impact on parenting capacity are limited. Child Protective Services (CPS) contact disproportionately impacts families marginalized by poverty, mental health disorders, and substance use disorders. Recently, there have been investigations into the significance of psychiatric illness and nonmental health-related factors that predict CPS custody arrangements. OBJECTIVE: To identify clinical factors associated with newborns' custody under CPS for mothers with antenatal psychiatric hospitalization. METHODS: We conducted a retrospective review of electronic medical records over a 10-year period (2012-2021) for patients who were pregnant during their inpatient psychiatric hospitalizations. We followed 81 patients (18 to 43 years old) who delivered within the hospital. The study endpoint was whether the newborn was placed under CPS custody. For the purposes of this study, psychiatric illness was categorized by the presence or absence of psychotic symptoms. We utilized logistic regressions to investigate the associations of these demographic and clinical factors with the study outcome of CPS custody. RESULTS: For the entire study population, 64.2% of newborns had CPS custody arrangements. In multivariate analysis, after adjusting for potential confounders, patients with psychotic symptoms were at increased odds of having CPS custody arrangements (odds ratio = 8.43; 95% confidence interval 2.16-32.85) compared with patients without psychotic symptoms. Furthermore, multivariate analyses revealed that patients with a history of homelessness also had a higher risk (odds ratio = 6.59; 95% confidence interval: 1.24-35.13) of CPS custody arrangements for their newborns than those without a history of homelessness. CONCLUSIONS: The results of this study suggest that among pregnant and psychiatrically hospitalized patients, those with psychotic symptoms are significantly more likely to have CPS custody arrangements compared to those without psychotic symptoms. However, it is important to note that psychotic symptoms were not definitive for the inability to parent appropriately. In fact, nearly 25% of the study population who had psychotic symptoms were able to successfully transition home with their newborns as mothers. This emphasizes the importance of optimizing the management of psychotic symptoms, particularly among those who have children or plan to have children. The findings of this study also highlight the chronic impacts that those who have struggled with homelessness may experience, including parenting capacity after homelessness resolves.

3.
Environ Sci Technol ; 58(9): 4070-4082, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38390827

RESUMO

Antibiotics are being increasingly detected in aquatic environments, and their potential ecological risk is of great concern. However, most antibiotic toxicity studies involve single-exposure experiments. Herein, we studied the effects and mechanisms of repeated versus single clarithromycin (CLA) exposure on Microcystis aeruginosa. The 96 h effective concentration of CLA was 13.37 µg/L upon single exposure but it reduced to 6.90 µg/L upon repeated exposure. Single-exposure CLA inhibited algal photosynthesis by disrupting energy absorption, dissipation and trapping, reaction center activation, and electron transport, thereby inducing oxidative stress and ultrastructural damage. In addition, CLA upregulated glycolysis, pyruvate metabolism, and the tricarboxylic acid cycle. Repeated exposure caused stronger inhibition of algal growth via altering photosynthetic pigments, reaction center subunits biosynthesis, and electron transport, thereby inducing more substantial oxidative damage. Furthermore, repeated exposure reduced carbohydrate utilization by blocking the pentose phosphate pathway, consequently altering the characteristics of extracellular polymeric substances and eventually impairing the defense mechanisms of M. aeruginosa. Risk quotients calculated from repeated exposure were higher than 1, indicating significant ecological risks. This study elucidated the strong influence of repeated antibiotic exposure on algae, providing new insight into antibiotic risk assessment.


Assuntos
Microcystis , Microcystis/metabolismo , Claritromicina/metabolismo , Claritromicina/farmacologia , Fotossíntese , Antibacterianos/toxicidade , Estresse Oxidativo , Metabolismo Energético
4.
Environ Pollut ; 344: 123347, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38215868

RESUMO

The influence of petroleum-based microplastics (MPs) on phytoplankton has been extensively studied, while research on the impact of biodegradable MPs, derived from alternative plastics to contest the environmental crisis, remains limited. This study performed a 63 days co-incubation experiment to assess the effect of polylactic acid MPs (PLA-MPs) on the growth, physiology, and carbon utilization of M. aeruginosa and the change in PLA-MPs surface properties. The results showed that despite PLA-MPs induced oxidative stress and caused membrane damage in M. aeruginosa, the presence of PLA-MPs (10, 50, and 200 mg/L) triggered significant increases (p < 0.05) in the density of M. aeruginosa after 63 days. Specifically, the algal densities upon 50 and 200 mg/L PLA-MPs exposure were increased by 20.91% and 36.31% relative to the control, respectively. Meanhwhile, the reduced C/O ratio on PLA-MPs surface and change in PLA-MPs morphological characterization, which is responsible for substantially increase in the aquatic dissolved inorganic carbon concentration during the co-incubation, implying the degradation of PLA-MPs; thus, provided sufficient carbon resources that M. aeruginosa could assimilate. This was in line with the declined intracellular carbonic anhydrase content in M. aeruginosa. This study is the first attempt to uncover the interaction between PLA-MPs and M. aeruginosa, and the finding that their interaction promotes the degrading of PLA-MPs meanwhile favoring M. aeruginosa growth will help elucidate the potential risk of biodegradable MPs in aquatic environment.


Assuntos
Microcystis , Microplásticos , Microplásticos/toxicidade , Plásticos/toxicidade , Ecossistema , Carbono , Poliésteres/toxicidade
5.
Heliyon ; 10(1): e23858, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38192867

RESUMO

Miscarriage is a significant public health concern worldwide, particularly in developing nations like Bangladesh. Moreover, people in coastal areas are more affected by miscarriage as compared to other areas. Increasing sea levels and salinity is the main reason for this discrepancy. This study aimed to investigate the association between different salinity levels (S1, S2, S3, S4, and S5) and miscarriage and unintended pregnancy. The outcome variables are pregnancy-related outcomes (miscarriage, unintended pregnancy), and the independent variables are different salinity levels. A frequency table and correlation analysis were done to find the descriptive scenarios of miscarriage, unintended pregnancy, and salinity levels. We found 621 miscarriage patients and 2271 unintended pregnant patients in our study. Furthermore, the Poisson regression model was used to observe the incidence of miscarriage and unintended pregnancy for different salinity levels. A higher amount of miscarriage and unintended pregnancy rate was found in Dhaka and Khulna, while these rates were lower in Barisal and Chittagong. However, the salinity levels were highest in Barisal and Khulna. Both miscarriage and unintended pregnancy are highly and negatively correlated with salinity levels. The Poisson regression model shows that the salinity levels s1-s5 are strongly associated with miscarriage. Lower and moderate levels of salinity are strongly associated with miscarriage than higher levels of salinity. Again, the average number of miscarriages decreases with the salinity levels. Likewise, unintended pregnancy was also negatively associated with salinity levels. However, it only reported a significant association with lower and moderate salinity levels, and higher salinity levels did not affect unintended pregnancy. Taking initiatives for raising awareness from government and non-government organizations, setting up deep tube water pumps extensively, and properly treating coastal areas women during pregnancy would be the ideal next step to reduce the miscarriage and unintended pregnancy rate in coastal zones in Bangladesh.

6.
Sci Total Environ ; 918: 170467, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38290685

RESUMO

The emission of carcinogenic, teratogenic, and mutagenic polycyclic aromatic hydrocarbons (PAHs) during municipal solid waste incineration (MSWI) of fly ash (FA) has attracted significant attention. Hydrothermal treatment (HT) has emerged as a practical approach for degrading PAHs during MSWI of FA by utilizing magnetite (Fe3O4) as a catalyst and hydrogen peroxide (H2O2) as an oxidizing agent. In this study, as an alternative to traditional hydroxyapatite (HAP), eggshell-derived magnetic hydroxyapatite (MHAP) was synthesized and applied in the hydrothermal catalytic degradation of PAHs in MSWI FA in an H2O2 system for the first time. The degradation efficiency of the PAHs is influenced not only by H2O2 but also by the choice of hydroxyapatite. Adding HAP or MHAP during hydrothermal treatment with H2O2 substantially reduced the overall PAH concentration and toxicity equivalent quantity (TEQ), superior to that without H2O2. MHAP demonstrated superior catalytic activity compared to HAP in the presence of H2O2 in the hydrothermal system. The hydrothermal detoxification of the PAHs increased with increasing MHAP dosage. By employing 0.5 mol/L H2O2 as the oxidant and 15 wt% MHAP as the catalyst, a total PAH degradation rate of 88.9 % was achieved, with a remarkable TEQ degradation rate of 98.3 %. Notably, the level of 4-6-ring PAHs, particularly benzo(a) pyrene (BaP) and dibenz(a,h)anthracene (DahA), with a TEQ of 1.0, was significantly reduced (by 69.4 % and 46.0 %, respectively). MHAP remained stable during the hydrothermal catalytic process, whereas H2O2 was effectively activated by MHAP and decomposed to produce strongly oxidizing hydroxyl (•OH) under hydrothermal conditions. •OH produced from the decomposition of H2O2 and metals on the surface of MHAP act as catalytically active centers, efficiently converting high-ring PAHs to low-ring PAHs. These findings provide valuable insights and a technological foundation for PAH detoxification in MSWI FA via hydrothermal catalytic oxidation.

7.
Ecotoxicol Environ Saf ; 267: 115620, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37866108

RESUMO

Aquatic ecosystems are heavily affected by microplastics (MPs), and its impacts on aquatic life have received extensive attention. However, it is still unclear how biodegradable MPs influence the growth and competition of phytoplankton. In this study, the response of growth dynamics, alternation in algal cell morphology and toxin-producing capability, and changes in the extracellular process of Microcystis aeruginosa (M. aeruginosa) and Scenedesmus obliquus (S. obliquus) were systematically studied in monoculture and co-culture conditions with and without the presence of polylactic acid MPs (PLA-MPs). The results indicated that although the loss of cell integrity was observed, PLA-MPs addition (50 mg/L) caused a 1.40- and 1.36-fold increase in cell densities of M. aeruginosa and S. obliquus in monoculture systems, respectively. This suggests the PLA-MPs more favored the growth of M. aeruginosa. This effect was manifested in co-culture conditions, because the degradation of PLA-MPs provided additional inorganic carbon in the experimental systems and benefited the growth of both M. aeruginosa and S. obliquus. Meanwhile, the synthesis of microcystins from the toxic M. aeruginosa was substantially reduced upon PLA-MPs exposure, which reduced the competitive advantage of M. aeruginosa over S. obliquus. Thus; the cell density of M. aeruginosa and S. obliquus showed 1.15- and 1.88-folds increasing compared to that without PLA-MPs addition. This interaction between PLA-MPs and algae weakened the competitive advantage of M. aeruginosa over S. obliquus, but their competitive outcomes remained unchanged. The results provided new insights into understanding the potential ecological risks of biodegradable plastics in aquatic ecosystems.


Assuntos
Clorofíceas , Microcystis , Scenedesmus , Ecossistema , Microplásticos , Plásticos , Poliésteres
8.
Environ Pollut ; 338: 122568, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37717899

RESUMO

Biomass fuel burning is a significant contributor of household fine particulate matter (PM2.5) in the low to middle income countries (LMIC) and assessing PM2.5 levels is essential to investigate exposure-related health effects such as pregnancy outcomes and acute lower respiratory infection in infants. However, measuring household PM2.5 requires significant investments of labor, resources, and time, which limits the ability to conduct health effects studies. It is therefore imperative to leverage lower-cost measurement techniques to develop exposure models coupled with survey information about housing characteristics. Between April 2017 and March 2018, we continuously sampled PM2.5 in three seasonal waves for approximately 48-h (range 46 to 52-h) in 74 rural and semi-urban households among the participants of the Bangladesh Cook Stove Pregnancy Cohort Study (CSPCS). Measurements were taken simultaneously in the kitchen, bedroom, and open space within the household. Structured questionnaires captured household-level information related to the sources of air pollution. With data from two waves, we fit multivariate mixed effect models to estimate 24-h average, cooking time average, daytime and nighttime average PM2.5 in each of the household locations. Households using biomass cookstoves had significantly higher PM2.5 concentrations than those using electricity/liquefied petroleum gas (626 µg/m3 vs. 213 µg/m3). Exposure model performances showed 10-fold cross validated R2 ranging from 0.52 to 0.76 with excellent agreement in independent tests against measured PM2.5 from the third wave of monitoring and ambient PM2.5 from a separate satellite-based model (correlation coefficient, r = 0.82). Significant predictors of household PM2.5 included ambient PM2.5, season, and types of fuel used for cooking. This study demonstrates that we can predict household PM2.5 with moderate to high confidence using ambient PM2.5 and household characteristics. Our results present a framework for estimating household PM2.5 exposures in LMICs, which are often understudied and underrepresented due to resource limitations.


Assuntos
Poluição do Ar em Ambientes Fechados , Material Particulado , Gravidez , Feminino , Humanos , Material Particulado/análise , Poluição do Ar em Ambientes Fechados/análise , Estudos de Coortes , Bangladesh , Culinária , Monitoramento Ambiental/métodos
9.
Environ Sci Technol ; 57(29): 10521-10531, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37449315

RESUMO

Studies concerning the toxicity of pollutant-loaded nanoplastics (NPs) toward humans are still in their infancy. Here, we evaluated the adsorption of microcystins (MCs) by pristine and aged polystyrene nanoplastics (PSNPs), prepared MCs-loaded aged PSNPS (1, 5, 10, 15, and 19 µg/mg), and systematically mapped the key molecular changes induced by aged and MCs-loaded PSNPs to human hepatoblastoma (HepG2) cells. According to the results, MC-LR adsorption is increased 2.64-fold by aging, and PSNP accumulation is detected in HepG2 cells. The cytotoxicity of the MC-LR-loaded aged PSNPs showed a positive relationship with the MC-LR amount, as the cell viability in the 19 µg/mg loading treatment (aPS-MC19) was 10.84% lower than aged PSNPs; meanwhile, more severe oxidative damage was observed. Primary approaches involved stressing the endoplasmic reticulum and reducing protein synthesis that the aged PSNPs posed for HepG2 cells, while the aggravated cytotoxicity in aPS-MC19 treatment was a combined result of the metabolic energy disorder, oxidative damage, endoplasmic reticulum stress, and downregulation of the MC-LR target protein. Our results confirm that the aged PSNPs could bring more MC-LR into the HepG2 cells, significantly interfere with biological processes, and provide new insight into deciphering the risk of NPs to humans.


Assuntos
Microcistinas , Microplásticos , Humanos , Idoso , Fígado , Hepatócitos , Estresse Oxidativo , Poliestirenos
10.
J Environ Manage ; 344: 118437, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37343476

RESUMO

The ecological impacts of micro(nano)plastics (MNPs) have attracted attention worldwide because of their global occurrence, persistence, and environmental risks. Increasing evidence shows that MNPs can affect soil nutrient cycling, but the latest advances on this topic have not systematically reviewed. Here, we aim to present the state of knowledge about the effects of MNPs on soil nutrient cycling, particularly of C, N, and P. Using the latest data, the present review mainly focuses on three aspects, including (1) the effects and underlying mechanisms of MNPs on soil nutrient cycling, particularly of C, N and P, (2) the factors influencing the effects of MNPs on soil nutrient cycling, and (3) the knowledge gaps and future directions. We conclude that MNPs can alter soil nutrient cycling via mediating soil nutrient availability, soil enzyme activities, functional microbial communities, and their potential ecological functions. Furthermore, the effects of MNPs vary with MNPs characteristics (i.e., polymeric type, size, dosage, and shape), chemical additives, soil physicochemical conditions, and soil biota. Considering the complexity of MNP-soil interactions, multi-scale experiments using environmental relevant MNPs are required to shed light on the effects of MNPs on soil nutrients. By learning how MNPs influence soil nutrients cycles, this review can guide policy and management decisions to safeguard soil health and ensure sustainable agriculture and land use practices.


Assuntos
Plásticos , Solo , Agricultura
11.
BMJ Open ; 13(5): e068539, 2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-37164456

RESUMO

PURPOSE: The Cook Stove Pregnancy Cohort Study (CSPCS) was designed to assess the effects of biomass fuel use on household air pollution (HAP) as well as the effects of HAP (fine particulate matter, PM2.5) on birth outcomes and acute lower respiratory infection (ALRI) among infants in Bangladesh. PARTICIPANTS: We recruited 903 women within 18 weeks of pregnancy from rural and semiurban areas of Bangladesh between November 2016 and March 2017. All women and their infants (N=831 pairs) were followed until 12 months after delivery and a subset have undergone respiratory and gut microbiota analysis. METHODS: Questionnaires were administered to collect detailed sociodemographic, medical, nutritional and behavioural information on the mother-child dyads. Anthropometric measurements and biological samples were also collected, as well as household PM2.5 concentrations. FINDINGS TO DATE: Published work in this cohort showed detrimental effects of biomass fuel and health inequity on birth outcomes. Current analysis indicates high levels of household PM2.5 being associated with cooking fuel type and infant ALRI. Lastly, we identified distinct gut and respiratory microbial communities at 6 months of age. FUTURE PLANS: This study provides an economical yet effective framework to conduct pregnancy cohort studies determining the health effects of adverse environmental exposures in low-resource countries. Future analyses in this cohort include assessing the effect of indoor PM2.5 levels on (1) physical growth, (2) neurodevelopment, (3) age of first incidence and frequency of ALRI in infants and (4) the development of the respiratory and gut microbiome. Additional support has allowed us to investigate the effect of in utero exposure to metals on infant neurodevelopment in the first year of life.


Assuntos
Poluição do Ar em Ambientes Fechados , Infecções Respiratórias , Lactente , Gravidez , Humanos , Feminino , Poluição do Ar em Ambientes Fechados/efeitos adversos , Poluição do Ar em Ambientes Fechados/análise , Estudos de Coortes , Bangladesh/epidemiologia , Material Particulado/efeitos adversos , Material Particulado/análise , Culinária , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/etiologia
12.
Environ Res ; 222: 115383, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36716806

RESUMO

Biochar has been widely applied in soil and water. However, the fate and transport of biochar are not yet fully understood. Here, biochar's disintegration, transport, and the effect of temperature on biochar transport in soil (purple soil)-water systems were investigated. The results showed that the potentially transportable components (PTC) of biochar for corn straw, wheat straw, rice straw, rice husk and wood biochar reached 6.22-7.60%, 5.96-12.29%, 11.77-12.45%, 5.34-6.26% and 5.08-6.14% by mass, respectively. An external force (ultrasound exposure) intensified the physical disintegration, including colloidal and nanoparticles from larger particles, thereby increasing the transport potential. The mass recovery rates of PTC for rice straw biochar after penetrating through soil at 5, 20 and 35 °C reached 44.25%, 32.97% and 10.98%, respectively, which was supported by the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory results. Elevated temperatures increased the hydrodynamic average diameter of PTC, and the Zeta potential of PTC and soil at 35 °C were less negative than those at 5 and 20 °C. As a result, biochar's transportability decreases with increasing temperature in the soil-water system, during which the enhanced PTC aggregation and the decreased electrostatic repulsion between biochar and soil particles played a crucial role. The increase in electrical conductivity in the soil-water system may be the main reason for the decrease in electrostatic repulsion at higher temperatures. The findings are helpful for an in-depth understanding of the environmental fate and managing the transport risk of biochar.


Assuntos
Oryza , Solo , Água , Carvão Vegetal , Temperatura
13.
Environ Sci Pollut Res Int ; 29(54): 81308-81320, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35731437

RESUMO

China, being the world's largest exporter, has now certain environmental commitments such as to achieve carbon neutrality before 2060. These commitments of China has raised a reasonable concern regarding the expected reduction in the production and export of pollution intensive goods in the future. Besides China, the most efficient countries in the region to produce these goods are most of the member countries from ASEAN. The current study therefore aims to analyze if in the future, China reduces the production and export of these goods, whether the selected ASEAN countries can be the next choice for the export of pollution intensive goods. Based on the data availability for the period 1990-2019, this study considers five selected ASEAN countries (ASEAN-5). The results are based on the Auto Regressive Distributive Lag (ARDL) bound testing approach to cointegration and Error Correction Modeling (ECM). The aggregate analysis of five pollution intensive goods (pulp and paper (341), industrial chemicals (351), non-metallic minerals products (369), iron and steel (371) and non-ferrous metals (372)) suggests that Foreign direct investment (FDI) inflow can significantly increase the export of pollution intensive goods only in case of Indonesia, Malaysia and Thailand. However, there is no significant effect of FDI on the export of pollution intensive goods in case of Philippines and Singapore. The disaggregate analyses of the five pollution intensive goods suggest that in each of the ASEAN-5 countries, FDI inflow can significantly increase the export of pollution intensive goods in some of these industries rather than in all of them. In nutshell, it is concluded that ASEAN-5 countries can be a potential choice for the export of pollution intensive goods in some of the pollution intensive industries but not in all of them.


Assuntos
Poluição Ambiental , Investimentos em Saúde , Poluição Ambiental/análise , Aço , Carbono , Ferro , Desenvolvimento Econômico
14.
J Hazard Mater ; 431: 128524, 2022 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-35220121

RESUMO

Microplastics (MPs) can sorb toxic substances and be colonized by microorganisms. However, the interactions between the adsorbed toxic substances and the MPs biofilm remains inadequately understood. Here, a 37-days microcosm experiment was conducted to investigate the influence of polystyrene microplastics (PS-MPs) on microcystin (MC-LR) behavior in turbulent scenarios. The results revealed that adsorption by PS-MPs was the primary process that led to a quick reduction of aquatic MC-LR concentrations. With the colonization of microorganisms on the PS-MPs, the attached biofilm altered the surface properties of PS-MPs, which enhanced the bio-adsorption of MC-LR. Meanwhile, microcystins degrading bacteria, such as Sphingomonadaceae and Methylophilaceae, inhabited in the biofilm, which facilitated the MC-LR biodegradation; this was also demonstrated by the identified MC-LR degradation products. Thus, the MC-LR concentration in water was constantly decreased, with a maximum removal capability of 35.8% in PS-MPs added groups. In addition, a 25% reduction of MC-LR was recorded in PS-MPs added static water. This suggested that the interaction between PS-MPs, biofilm, and MC-LR may be prevalent in natural waters. Our results indicate MPs as vectors for toxic substances could be a double-edged sword (adsorption and biodegradation), which provides new insights for understanding the ecological risks of microplastics.


Assuntos
Microcistinas , Microplásticos , Toxinas Marinhas , Microcistinas/metabolismo , Microplásticos/toxicidade , Plásticos , Água
15.
Sci Total Environ ; 822: 153405, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35092774

RESUMO

BACKGROUND: Studies demonstrated associations between maternal exposure to household air pollution from cooking and increased risk of adverse birth outcomes in offspring; however, the modifying effect of socioeconomic status (SES) on this association has not been explored. OBJECTIVES: In a cohort of pregnant women with 800 single live births between 2016 and 2017 in rural and semi urban areas of Bangladesh, we tested the hypotheses that kitchen location and cooking fuel type affect birth outcomes (birth weight, low birth weight [LBW] and small for gestational age [SGA]) and these associations vary by SES. METHODS: Demographic characteristics including SES, kitchen location and fuel type were assessed in prenatal visits. Neonatal anthropometric measurements were recorded within 72 h of births. We performed multivariable linear and logistic regressions adjusting for potential confounders to test the study hypotheses. RESULTS: For newborns from households with indoor kitchens, adjusted mean birth weight was 65.13 g (95% confidence interval [CI]: -118.37, -11.90) lower and the odds of LBW and SGA were 58% (odds ratio [OR]:1.58, 95% CI: 1.12, 2.24) and 41% (OR: 1.41, 95% CI: 1.05, 1.92) higher compared to those born in households with outdoor kitchens. We found SES significantly modified the associations between kitchen location and birth outcomes in households using biomass fuels. Newborns from low SES households with indoor kitchens had 89 g lower birth weight and a higher odds of being born with LBW (OR: 2.08, 95% CI 1.23, 3.58), and SGA (OR: 1.70, 95% CI 1.06, 2.76) than those born in high SES households using outdoor kitchens. CONCLUSIONS: In areas with poor access or affordability to clean fuel such as in our study population, cooking in an outdoor kitchen can reduce the burden of LBW and SGA, particularly for low SES households. Promoting outdoor kitchens is a possible intervention strategy to mitigate adverse birth outcomes.


Assuntos
Poluição do Ar em Ambientes Fechados , Poluição do Ar , Poluição do Ar em Ambientes Fechados/análise , Culinária , Características da Família , Feminino , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Gravidez
16.
J Hazard Mater ; 424(Pt D): 127719, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34802826

RESUMO

In this study, a Microcystis aeruginosa-based photobioreactor (M. aeruginosa-based PBR) was developed for the removal of cadmium (Cd2+) from diluted actual mine wastewater (DW) and Cd2+-contained simulated wastewater (SW), with a uniform Cd2+ concentration of 0.5 mg/L. For the DW and SW, both K+ -abundant (DWA & SWA) and K+-insufficient (DWB & SWB) treatments were conducted. It was found that continuous supplementation of K+ benefited Cd2+ removal. The Cd2+ removal efficiency in SWA reached 70% during the 41 days of operation, which was 20% higher than that in the SWB. The K+ addition triggered great higher Cd2+ removal efficiency (90%) in the DWA in comparison to the SWA. The Cd2+ assimilation by M. aeruginosa and Cd2+ retention on M. aeruginosa surface were the primary processes involved in the PBR system. The K+ starvation triggered a 45% and 43% loss of M. aeruginosa biomass in the DWA and the DWB, respectively. Hence, the Cd2+ removal efficiency in DWB increased significantly, and this was attributed to the increased abundance of non-living cells and enhanced bioretention of Cd2+. The results revealed that continuous K+ supplementation enhanced the Cd2+ removal efficiency in the M. aeruginosa-based PBR jointly by prompting algal cell growth, Cd2+ assimilation and biosorption, as well as Cd2+ retention on the algal cells.


Assuntos
Microcystis , Cádmio , Fotobiorreatores , Potássio , Águas Residuárias
17.
Environ Sci Pollut Res Int ; 29(16): 23249-23263, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34800274

RESUMO

In 2013, the Chinese government officially announced the Belt and Road Initiative (BRI). Since then, environmentalists have raised concerns regarding the environmental impact of trade between China and BRI countries. Therefore, the current study aims to analyze the environmental impact of the two aspects of BRI countries' trade: First, it examines the environmental impact of trade openness between China and BRI countries. Second, it examines the environmental impact of trade openness among BRI countries. For this purpose, the current study employs the two-step system GMM model with a panel dataset for the period 2001-2018. The results obtained for the whole sample of 88 selected BRI countries suggest that the trade openness between China and BRI countries significantly reduces CO2 emissions. However, the trade openness among BRI countries has no significant effect on CO2 emissions. In addition, BRI countries' exports to China do not have a significant effect on CO2 emissions. However, BRI countries' imports from China significantly reduce CO2 emissions in these countries. The results obtained for the subsamples of BRI countries suggest that the trade openness between China and BRI countries, BRI countries' exports to China, and BRI countries' imports from China have no significant effect on CO2 emissions in both low-income and high-income BRI countries. Moreover, the trade openness among BRI countries significantly increases CO2 emissions in low-income BRI countries only.


Assuntos
Dióxido de Carbono , Análise de Dados , Dióxido de Carbono/análise , China , Desenvolvimento Econômico , Meio Ambiente , Renda
18.
Neurobiol Dis ; 161: 105546, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34742878

RESUMO

Febrile seizures (FS) are common, affecting 2-5% of children between the ages of 3 months and 6 years. Complex FS occur in 10% of patients with FS and are strongly associated with mesial temporal lobe epilepsy. Current research suggests that predisposing factors, such as genetic and anatomic abnormalities, may be necessary for complex FS to translate to mesial temporal lobe epilepsy. Sex hormones are known to influence seizure susceptibility and epileptogenesis, but whether sex-specific effects of early life stress play a role in epileptogenesis is unclear. Here, we investigate sex differences in the activity of the hypothalamic-pituitary-adrenal (HPA) axis following chronic stress and the underlying contributions of gonadal hormones to the susceptibility of hyperthermia-induced seizures (HS) in rat pups. Chronic stress consisted of daily injections of 40 mg/kg of corticosterone (CORT) subcutaneously from postnatal day (P) 1 to P9 in male and female rat pups followed by HS at P10. Body mass, plasma CORT levels, temperature threshold to HS, seizure characteristics, and electroencephalographic in vivo recordings were compared between CORT- and vehicle (VEH)-injected littermates during and after HS at P10. In juvenile rats (P18-P22), in vitro CA1 pyramidal cell recordings were recorded in males to investigate excitatory and inhibitory neuronal circuits. Results show that daily CORT injections increased basal plasma CORT levels before HS and significantly reduced weight gain and body temperature threshold of HS in both males and females. CORT also significantly lowered the generalized convulsions (GC) latency while increasing recovery time and the number of electrographic seizures (>10s), which had longer duration. Furthermore, sex-specific differences were found in response to chronic CORT injections. Compared to females, male pups had increased basal plasma CORT levels after HS, longer recovery time and a higher number of electrographic seizures (>10s), which also had longer duration. Sex-specific differences were also found at baseline conditions with lower latency to generalized convulsions and longer duration of electrographic seizures in males but not in females. In juvenile male rats, the amplitude of evoked excitatory postsynaptic potentials, as well as the amplitude of inhibitory postsynaptic currents, were significantly greater in CORT rats when compared to VEH littermates. These findings not only validate CORT injections as a stress model, but also show a sex difference in baseline conditions as well as a response to chronic CORT and an impact on seizure susceptibility, supporting a potential link between sustained early-life stress and complex FS. Overall, these effects also indicate a putatively less severe phenotype in female than male pups. Ultimately, studies investigating the biological underpinnings of sex differences as a determining factor in mental and neurologic problems are necessary to develop better diagnostic, preventative, and therapeutic approaches for all patients regardless of their sex.


Assuntos
Hipertermia Induzida , Convulsões Febris , Animais , Corticosterona , Feminino , Humanos , Hipertermia Induzida/efeitos adversos , Sistema Hipotálamo-Hipofisário , Masculino , Ratos , Convulsões/etiologia , Convulsões Febris/etiologia , Caracteres Sexuais
19.
J Hazard Mater ; 413: 125374, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-33588335

RESUMO

Microcystis aeruginosa (M. aeruginosa) was found to be capable of cadmium (Cd2+) assimilation. Potassium (K+), an essential factor in transmembrane transport, can possibly manipulate the interaction between Cd2+ and M. aeruginosa. In this study, the effect of available K+ levels on Cd2+ toxicity in M. aeruginosa is examined. The results showed that the K+ level was positively linked with toxicity of Cd2+ to M. aeruginosa. And with respect to the M. aeruginosa incubated in K+ = 460 µM treatment, the release of extracellular polymeric substance was augmented, which benefited the retention of Cd2+ on the M. aeruginosa surface. In addition, the assimilation of Cd2+ showed a 3.42-fold increase in comparison to that without K+ supplement. Moreover, the enhanced K+ level caused the up-regulation of the Cd2+ transporting protein and down-regulation of the Cd2+ efflux protein, associated with the positive energy metabolism response. These results documented that the K+ availability could influence the toxicity of Cd2+ to M. aeruginosa jointly through the manipulation of Cd2+ assimilation, excretion, and the biological response. These findings may attach importance to the effects of K+ level on Cd2+ assimilation by M. aeruginosa and shed a degree of light on the enhanced Cd2+ removal using algal-based technology.


Assuntos
Microcystis , Cádmio/toxicidade , Matriz Extracelular de Substâncias Poliméricas , Potássio
20.
Int J Hosp Manag ; 98: 103037, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36540853

RESUMO

The COVID-19 pandemic has delivered one of the worst economic shocks in modern history and the hospitality sector has been severely affected. Since small businesses from the hospitality sector are known to be relatively more susceptible to the economic complications arising from a crisis, we explore the underlying factors and management practices that influence their continuity of operations as they continue to struggle with the on-going COVID-19 crisis in Pakistan. Using a phenomenological approach, in-depth interviews were conducted to comprehend the experiences of owners-managers. The findings show that government support, cordial relationships with stakeholders, self-determination of entrepreneurs and formal planning are the most crucial factors that shaped the immediate adjustments of operational activities in response to COVID-19. These resilient practices are hygiene concerns, increased promotion through social media, innovative marketing practices (e.g., revised offerings), operational cost-cutting and employee training to comply with changing standard operating procedures from the government and industry. The practical and theoretical implications are also discussed.

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