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This study aims to synthesize and characterize silver nanoparticles (AgNPs) from Leucaena leucocephala leaf extract and evaluate their effectiveness in photo-catalytically degrading indigo carmine (IC) dye in an aqueous solution. The synthesized AgNPs were characterized using UV-visible spectrophotometry (UV-Vis), diffuse reflectance spectroscopy (DRS), Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), and X-ray diffraction (XRD) techniques. Response surface methodology (RSM) based on central composite design (CCD) was employed to optimize the conditions for the photocatalytic degradation of IC dye under solar light. The results show that 97.52% of the maximum photodegradation of IC dye was achieved using a dye concentration, catalyst volume, and reaction time of 19.7 mgL-1, 4.47 mL, and 97 min, respectively. RSM results revealed optimal conditions for IC dye degradation under solar irradiation. Moreover, the kinetics study of IC dye showed a good correlation with the pseudo-first order kinetic model. [ABSTRACT FROM AUTHOR]

The concentrations of As, Cd, Cr, Pb and Fe in water, sediment and Oreochromis niloticus tissues and the chromosomal aberrations, genetic differentiation and genomic template stability (GTS) of O. niloticus in 2 reservoirs near iron ore mine and one reference reservoir were investigated. Genetic differentiation and %GTS were evaluated by inter simple sequence repeat analysis. The As, Cd and Cr concentrations in fish from 2 mine reservoirs exceeded the standards. Seven types of chromosomal aberrations were found in fish from the iron ore mine: single chromatid gap, iso chromatid gap, centromere gap, dicentric chromosome, fragmentation, deletion, and ring chromosome. The average percentages of aberrant chromosomes in the cells of O. niloticus from mine reservoirs 1, 2 and the reference reservoir were 23.6, 16.8 and 2.2, respectively. Genetic differentiation and subsequent dendrogram analysis separated O. niloticus into 3 clusters, corresponding to the 2 mine reservoirs and the reference reservoir. The %GTS ranges of O. niloticus were 68.75–83.75, 71.88–85.19 and 83.58–97.01, respectively. Metals accumulations in O. niloticus could induce the occurrence of chromosomal aberrations and genetic differentiation. [ABSTRACT FROM AUTHOR]

This study was performed heavy metals (As, Cd, Cr, and Pb) in water, soil and frogs around an electronic-waste dump site. The bioaccumulation factors (BAFs) of heavy metals in three frog species and potential human health risks were assessed. Heavy metals were analyzed using inductively coupled plasma-optical emission spectrometry. The Cd and Pb concentrations in water samples and As and Pb concentrations in soil samples from within the e-waste dump site exceeded the standards. The heavy metal concentrations in the muscles of three frog species were as follows: Cr > Pb > As > Cd, and there were no significant differences among frog species except in the case of Pb (p < 0.05). Only the Cr concentrations exceeded the food quality standards. The relative order of the BAFs for heavy metals in frogs as a result of uptake from the water and soil was Cr > As > Pb > Cd and Cr > As > Cd > Pb, respectively, which indicated that the uptake from water was greater than that from the soil. The assessment of the health risk index and carcinogenic risk (CR) indicated potential human health effects from As, Cr, and Pb via the consumption of frogs. [ABSTRACT FROM AUTHOR]

This study aimed to investigate contamination by heavy metals including arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb), and manganese (Mn) and to conduct a cytotoxic assessment ofEsomus metallicusfrom a gold mine area compared with that from the non-affected area. TheE. metallicussamples were collected downstream of a gold mine area. The heavy metal concentrations were analysed by inductively coupled plasma optical emission spectroscopy (ICP-OES). The average amounts of As, Cd, Cr, Pb and Mn in water andE. metallicussamples from the gold mine area were 0.368 ± 0.009, 0.008 ± 0.006, 0.009 ± 0.001, 0.006 ± 0.002, 1.438 ± 0.058 mg/L, 0.65 ± 0.25, 0.03 ± 0.03, 2.12 ± 0.05, 0.25 ± 0.07 and 18.28 ± 6.82 mg/kg, respectively. The difference of As, Cr and Mn concentrations inE. metallicussamples between gold mine and non-affected areas was statistically significant (p < 0.05) except for Cd and Pb. The diploid chromosome number ofE. metallicusfrom both areas was2n = 50. There are six types of chromosomal aberrations including centric fragmentation (CF), centric gap (CG), single chromatid gap (SCG), fragmentation (F), deletion (D) and polyploidy (P). The most common chromosomal aberration type in the samples from the gold mine area was CG, and the difference in chromosomal aberration and the number of cells with chromosomal aberrations inE. metallicusbetween the study areas was statistically significant (p < 0.05). The percentages of chromosomal aberrations in theE. metallicussamples from gold mine and non-affected areas were 14.66 and 3.00, respectively. [ABSTRACT FROM AUTHOR]

The objectives of this study are to investigate the chromosome aberrations of the East Asian Bullfrog (Hoplobatrachus rugulosus) in the gold mine area compared to an unaffected area. Three H. rugulosus were collected, and chromosome aberrations were studied using bone marrow. The level of arsenic was measured in water, sediment and H. rugulosus samples. The average concentrations of arsenic in the water and sediment samples from the gold mine and unaffected areas were 0.03±0.003 mg/l and not detected in water as well as 351.59±5.73 and 1.37±1.07 mg/kg in sediment, respectively. The gold mine values were higher than the permissible limit of the water and soil quality standards, but the arsenic concentrations in the samples from the unaffected area were within prescribed limit. The average concentrations of arsenic in H. rugulosus samples from the gold mine and unaffected areas were 0.39±0.30 and 0.07±0.01 mg/kg, respectively, which were both lower than the standard of arsenic contamination in food. The diploid chromosome number of H. rugulosus in both areas was 2n=26, and the percentage of chromosome breakages of H. rugulosus in the gold mine area were higher than the unaffected area. There were eight types of chromosome aberrations, including a single chromatid gap, isochromatid gap, single chromatid break, isochromatid break, centric fragmentation, deletion, fragmentation and translocation. The most common chromosome aberration in the samples from the affected area was deletion. The difference in the percentage of chromosome breakages in H. rugulosus from both areas was statistically significant (p<0.05). [ABSTRACT FROM AUTHOR]