Total arsenic and speciation analysis of saliva and urine samples from individuals living in a chronic arsenicosis area in China.

BACKGROUND: It is generally acknowledged that the determination of harmful chemical compounds excreted into saliva is useful for assessing their exposure levels. The aim of the present study was to compare the total arsenic and its species in saliva and urine samples collected from the people residing in an arsenic-contaminated area of China and to further verify the feasibility of using salivary arsenic as a new biomarker of arsenic exposure. METHODS: Total arsenic and speciation analyses in urine and saliva samples among 70 residents exposed to arsenic from drinking water in Shanxi, China were carried out by high-performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP/MS). RESULTS: The result showed that, total arsenic concentration in saliva was relatively lower than in urine samples, but it existed a strong positive correlation with total urinary arsenic, drinking water arsenic and different skin lesions. For arsenic metabolism analyses, AsIII, AsV, MMA, and DMA were detected in all of the urine samples with the dominating species of DMA (73.2%). Different with urinary arsenic species, most arsenic species in saliva were not methylated. The major species in saliva was iAs (AsIII + AsV, 76.18%), followed by DMA (13.08%) and MMA (9.13%). And the primary methylation index (PMI), second methylation index (SMI) and proportion of the four different species (AsIII, AsV, MMA, and DMA) in saliva showed no significant positive relationship with that of in urine. CONCLUSIONS: These findings indicated saliva may be used as a useful tool for biological monitoring of total arsenic exposure in the crowd rather than an efficient tool for assessing arsenic metabolism in human body after exposed to arsenic.

[Comparison of the total arsenic concentration between saliva and blood after oral administration of sodium arsenite to rats].

OBJECTIVE: To compare the total arsenic concentration between blood and saliva after oral administration of sodium arsenite to SD rats. METHODS: A single oral gavage dose of sodium arsenite (20mg/kg) was administrated to 21 adult male Sprague-Dawley rats. Then collected blood and saliva samples at 0, 1-2, 4-5, 7-8, 11-12, 17-18, 23-24 hour for total arsenic detection. The blood samples were detected for total arsenic concentration by Atomic Fluorescence Spectrometry (AFS-230) and the salivary arsenic were detected by inductively coupled plasma mass spectrometry (ICP-MS). RESULTS: After intake of 20 mg/kg BW sodium arsenite, the total arsenic concentration in blood of SD rats was increased rapidly, and reached the peak value at the 1-2 hour, then descended gradually. However, there was a second peak value at the 7-8 hour. The upward trend of salivary arsenic was more slowly than blood arsenic, and reached the peak value at the 7-8 hour, then descended gradually. The variation tendency of salivary arsenic and blood arsenic with time were basically the same. Besides, there was an obvious positive association between them, the correlation coefficient was 0.678, P < 0.01. CONCLUSION: The excretion of arsenic in saliva was slower than that of blood samples after administrated a single oral gavage dose of sodium arsenite (20 mg/kg) to SD rate, but the metabolism mode of arsenic in saliva was similar with that in blood, suggested that salivary arsenic can also well reflect the exposure level of arsenic in the body.