Analysis on the arsenic speciation in urine of rats treated with sodium arsenite and sodium arsenate / 中国地方病学杂志

ABSTRACT

Objective To analyze the levels and speciation of arsenic metabolites in urine of rats treated with sodium arsenite and sodium arsenate in order to investigate the different aspects of metabolism between sodium arsenite and sodium arsenate,thus to understand further the basic data about relationship between it's metabolism and mechanism of toxicity. Methods Seventy Wistar rats,weighting 80-120 g,were divided into 7 groups of 10 each,such as normal control group,high,middle and low sodium arsenite group and high,middle and low sodium arsenate group. After the animals were fed for one month,the urine was collected by metabolic cage in 12 hours. Applying the high efficiency liquid chromatography and hydride genesis atomic fluorescence spectroscopy (HPLC-HGAFS),the levels and speciation of arsenic metabolites were determined in urine of rats. Meanwhile,the recovery rate of dimethyl arsinic acid(DMA) would be determined to estimate the degree of accuracy of results. Results The levels of iAs~(3+),iAs~(5+) and DMA in middle sodium arsenite group[(121.66±1.26),(10.26±2.68),(200.91±0.56) μg/L]were higher than the high sodium arsenite group[(113.20±0.75),(5.16±1.32),(147.70±μ0.77)μg/L,all P < 0.05]and low sodium arsenite group[(79.35±2.12),(5.13±2.25),(56.35±1.23)μg/L,all P < 0.05]. The levels of iAs~(3+) and DMA in middle sodium arsenate group[(315.81±1.69),(245.12±1.18)μg/L]were higher than the high sodium arsenate group[(85.03±0.56),(110.34±1.04)μg/L,all P< 0.05]and low sodium arsenate group[(22.97±2.67),(15.75±2.15)μg/L,all P < 0.05]. Compared with sodium arsenate group,the levels of iAs~(3+) and DMA in high and low sodium arsenite group were higher(all P < 0.05) ; and the levels of iAs~(3+) and DMA in middle sodium arsenite group were lower(all P < 0.05). Meanwhile,the average urinary recovery rate of DMA of rats in different sodium arsenite group were 94.80%-102.70%,and the average urinary recovery rate of DMA of rats in different sodium arsenate group were 95.33%-108.40%. Conclusion The speciation and levels of arsenic are influenced by the external exposure dose,and some distinction appeared in the metabolism and metabolic path between sodium arsenite and sodium arsenate in urine in vivo.