Cytotoxic evaluation of rice field frogs (Fejervarya limnocharis) from gold mine area with arsenic contamination

Abstract

The objectives of this study were to investigate chromosomal aberrations in rice field frogs (Fejervarya limnocharis) from gold mine area compared to those from non-affected area. Three frogs were collected from each site, and chromosomal aberrations were studied in their bone marrow. Arsenic (As) was also measured in water and sediment from both areas. The average As concentrations in samples from the gold mine and the non-affected areas were 0.03 ± 0.003 mg/L and not detected in water and 351.59 ± 5.73 and 1.37 ± 1.07 mg/kg in sediment, respectively. The values in the gold mine were still higher than that allowed by the water and soil quality standards; however, the As concentrations in the samples from the non-affected area were acceptable. The average concentrations of As in the frog samples from the gold mine and the non-affected areas were 0.35 ± 0.33 and 0.07 ± 0.01 mg/kg, respectively, which were both lower than the standard of As contamination in food. The diploid chromosome number of frogs in both areas was 2n = 26, and the percentage of chromosomal aberrations in rice field frogs in the gold mine area was higher than in the non-affected area. There were seven types of chromosomal aberrations observed: single chromatid gap, isochromatid gap, single chromatid breaks, deletion, fragmentation, centric fragmentation and polyploidy. The most common chromosomal aberration in the samples from the affected area was the single chromatid gap. The difference in the percentages of chromosomal aberrations in rice field frogs from each area was statistically significant (p < 0.05).