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1.
Environ Pollut ; 349: 123985, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621450

RESUMO

Microplastics pose a significant environmental threat, with potential implications for toxic chemical release, aquatic life endangerment, and human food chain contamination. In Asia, rapid economic growth coupled with inadequate waste management has escalated plastic pollution in rivers, positioning them as focal points for environmental concern. Despite Asia's rivers being considered the most polluted with plastics globally, scholarly attention to microplastics in the region's freshwater environments is a recent development. This study undertakes a systematic review of 228 scholarly articles to map microplastic hotspots in Asian freshwater systems and synthesize current research trends within the continent. Findings reveal a concentration of research in China and Japan, primarily investigating riverine and surface waters through net-based sampling methods. Polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET) emerge as the predominant microplastic types, frequently observed as fibers or fragments. However, the diversity of sampling methodologies and reporting metrics complicates data synthesis, underscoring the need for standardized analytical frameworks to facilitate comparative analysis. This paper delineates the distribution of microplastic hotspots and outlines the prevailing challenges and prospects in microplastic research within Asian freshwater contexts.


Assuntos
Monitoramento Ambiental , Microplásticos , Rios , Poluentes Químicos da Água , Microplásticos/análise , Rios/química , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Ásia , China , Japão , Plásticos/análise
2.
Chemosphere ; 286(Pt 1): 131493, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34346332

RESUMO

In this study, Polyphenols functionalized Graphitic Hematite Nanocomposite (PGHN) was used as an adsorbent to remove Caesium (Cs) ions from a simulated solution. The nanocomposite was produced by synthesizing iron oxide nanoparticles using orange peel extract (OPE) as the reducing and capping agent in the presence of graphite produced from sugarcane bagasse. The nanocomposite exhibited a scaly morphology and the mean particle size of rhombohedral structured hematite nanoparticles was found to be 148.9 nm. The simulated solution of Cs ions was treated with PGHN and the treatment conditions were optimized by batch method. The concentration of Cs ion in the treated solution was determined using atomic emission spectroscopy (AES). The maximum Cs adsorption of 97.95% was attained at an optimum condition of pH - 9.0 and adsorbent dose - 70 mg/mL for treatment period of 110 min. The experimental data of adsorption fitted well with pseudo 1st order kinetics and was favorable for both Langmuir and Freundlich isotherm models. The study reports a facile method for the production of nanocomposite using agro-wastes such as sugarcane bagasse and orange peels. The synthesized nanocomposite was used as an adsorbent for the removal of toxic Cs and can be further used for industrial wastewater treatment.


Assuntos
Grafite , Nanocompostos , Poluentes Químicos da Água , Césio , Compostos Férricos , Polifenóis , Poluentes Químicos da Água/análise
3.
Ecotoxicol Environ Saf ; 164: 629-640, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30165340

RESUMO

Exposure to ionizing radiation is harmful to any living organism. It may cause varying levels of genetic mutation or ultimately death. Synthetic compounds have been used to counteract the hazardous effect of radiation on the live cells, but the possibility of these synthetic compounds being harmful to the organism being treated also exists. Herbal formulations are thus being explored as a possible alternative for the synthetic radioprotectant. Induction of DNA damage in fishes caused by ionizing radiation and its protection by phytocompounds is a hardly studied topic. In this study, we analyzed the radioprotective effect of Gymnema sylvestre leaves extract (GS) and its active compound gymnemagenin (GG) against different doses of gamma radiation (60Co) on the freshwater fish Pangasius sutchi. The radioprotective efficacy was assessed by micronuclei and alkaline comet assays. The freshwater fish P. sutchi was pre-treated with intramuscular injection (IM) of amifostine (83.3 mg/kg of B.W.), GS (25 mg/kg of B.W.) and GG (0.3 mg/kg of B.W.), 1 h prior to the gamma radiation. The fishes were exposed to LD30, LD50 and LD70 of gamma radiation and the protection activities were assessed by analyzing the number of micronuclei (MN) and erythrocytic abnormalities in the blood after 2, 4, 8, 16 and 32 days after exposure. Compared to the irradiated fishes, frequency of erythrocytic abnormalities were decreased in response to the radio-protection in the amifostine treated groups for all three doses of gamma radiation (LD70 - 77.62%), (LD50 - 80.11%) and (LD30 - 82.30%); GS (LD70 - 62.66%), (LD50 - 69.74%) and (LD30 - 70.81%); and GG (LD70 - 49.42%), (LD50 - 53.43%) and (LD30 - 58.42%). Similarly, a significant radio-protective effect in terms of decremented DNA damage was observed using the comet assay after post exposure. The percentage of protection noted for amifostine was (LD70 - 58.68%), (LD50 - 64.52%) and (LD30 - 74.40%); GS (LD70 - 53.84%), (LD50 - 59.02%) and (LD30 - 65.97%); GG (LD70 - 49.85%), (LD50 - 52.56%) and (LD30 - 64.30%). From the current study, we can conclude that the radioprotective efficacy of the GS is similar to the synthetic compound (amifostine) and also greater than the bioactive compound (GG). The synergetic effect of the plant extract which leads to a better protection than the bioactive compound must be further studied. MN and Comet assays can easily identify the damage due to radiation exposure and thus can be used as predictive biomarkers for aquatic organisms exposed to radiation.


Assuntos
Biomarcadores/análise , Peixes-Gato , Raios gama/efeitos adversos , Dose Letal Mediana , Extratos Vegetais/farmacologia , Protetores contra Radiação/farmacologia , Alcaloides/farmacologia , Amifostina/farmacologia , Animais , Bioensaio , Ensaio Cometa , Dano ao DNA/efeitos da radiação , Relação Dose-Resposta a Droga , Feminino , Água Doce , Gymnema sylvestre/química , Masculino , Testes para Micronúcleos , Compostos Fitoquímicos/farmacologia , Folhas de Planta/química
4.
Toxicol Ind Health ; 27(10): 867-72, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22083425

RESUMO

BACKGROUND: Radiation workers are constantly exposed to low background radiation which is their occupational hazard. This continuous and prolonged exposure produces genotoxicity and cancerous condition in many workers. The authors have tested casein phosphopeptides (CPP) as a radioprotectant against low background radiation using animal models. METHODS: Fermented milk was produced by addition of a bacterial culture, Lactobacillus acidophilus to a commercially available milk brand. After the fermentation process is completed in the milk, CPP is isolated from fermented milk by enzymatic hydrolysis-based method. The radioprotective role of CPP was proved using albino mice and Catla catla fish. RESULTS: The micronucleus assay showed higher level of cell deformation and micronucleus formation in the control animal cells than the test animal cells. CPP has found to be having radioprotective activity potential. CONCLUSIONS: This radioprotective potential of CPP can be harnessed to produce formulations which can be used by radiation workers and personnel exposed to low ionization background as an occupational hazard, thus reducing the risk and preventing any type of cancer.


Assuntos
Antimutagênicos/administração & dosagem , Carpas/fisiologia , Radioisótopos de Cobalto/efeitos adversos , Neoplasias Induzidas por Radiação/prevenção & controle , Fosfopeptídeos/administração & dosagem , Protetores contra Radiação/administração & dosagem , Animais , Caseínas/administração & dosagem , Modelos Animais de Doenças , Fermentação , Masculino , Camundongos , Micronúcleos com Defeito Cromossômico/efeitos da radiação , Testes para Micronúcleos , Leite , Doenças Profissionais/diagnóstico por imagem , Doenças Profissionais/prevenção & controle , Exposição Ocupacional/efeitos adversos , Radiação , Proteção Radiológica , Cintilografia
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