[Distribution of chromium in whole blood and urine among general population in China between year 2009 and 2010].

OBJECTIVE: To evaluate the chromium (Cr) levels in blood and urine among general population in China between 2009 and 2010, and thereby to analyze its prevalent features. METHODS: From year 2009 to 2010, a total of 11 983 subjects of general population aged between 6 and 60 year-old were recruited from 24 districts in 8 provinces in eastern, central and western China mainland, by cluster random sampling method. The information about their living environment and health status were collected by questionnaire, and 11 983 blood samples and 11 853 urine samples were also collected. Inductively coupled plasma mass spectrometry (ICP-MS) was applied to test the Cr level both in blood and urine; and the Cr distribution in blood and urine among groups of population in different ages, genders and districts, were then analyzed. RESULTS: Among general population in China, the geometric mean (GM) of Cr concentration in blood was 1.19 µg/L, with median at 1.74 µg /L and 95% percentile at 5.59 µg/L. The Cr concentration in blood among males and females were separately 1.18 µg/L and 1.20 µg/L(P > 0.05); while its GM in the groups of population aged 6 - 12, 12 - 16, 16 - 20, 20 - 30, 30 - 45 and 45 - 60 years old were 1.00, 1.22, 1.01, 1.40, 1.27 and 1.30 µg/L (P < 0.01), respectively; and the figures in populations from eastern, central and western China were 1.00, 1.70 and 1.98 µg/L (P < 0.01), respectively. Among general population, the GM of Cr concentration in urine was 0.53 µg/L, with median was lower than 0.42 µg/L and 95% percentile at 3.53 µg/L. The Cr concentration in urine among males and females were separately 0.52 µg/L and 0.53 µg/L (P > 0.05);while its GM in the groups of population aged 6 - 12, 12 - 16, 16 - 20, 20 - 30, 30 - 45 and 45 - 60 years old were 0.56, 0.60, 0.52, 0.50, 0.52 and 0.46 µg/L (P < 0.01), respectively;and the figures in populations from eastern, central and western China were 0.58, < 0.42 and 0.60 µg/L (P < 0.01), respectively. CONCLUSION: The study reported the Cr levels in blood and urine among general population in China, and thereby provided basic data evidence for the following Cr biological monitoring studies in near future.

[Monitoring indexes for early renal injury in the workers exposed to mercury].

OBJECTIVE: To study the diagnostic method for early renal injury in the workers exposed to mercury (Hg). METHODS: The contents of urinary Hg were determined by chemical method. Urinary microalbumin (mALB), beta(2)-microglodulin (beta(2)-MG) and retinol binding protein (RBP) levels were measured with total quantitative enzyme immunoassay. The activities of urinary N-acetyl-beta-D-glucosaminidase (NAG) and gamma-glutamyl transferase (gamma-GT) were determined by rate methods. Urinary creatinine (Cr) was measured by using picric acid method. RESULTS: The levels of urinary BRP, beta(2)-MG, NAG and gamma-GT in exposed workers [(439.7 +/- 201.4), (141.4 +/- 56.3) micro g/g Cr and (12.3 +/- 5.7), (60.3 +/- 18.5) U/g Cr respectively] were significantly higher than those in controls (P < 0.05, P < 0.01). The levels were increased gradually with the increasing contents of urinary Hg. The positive detection rate for single or two combined indexes was rather lower whereas that for 4 combined indexes was as high as 85.5%. A positive correlation was noted between the contents of urinary Hg and urinary BRP, beta(2)-MG, NAG and gamma-GT (r: 0.466, 0.379, 0.323, 0.311, P < 0.05). Urinary RBP was correlated to urinary beta(2)-MG, NAG and gamma-GT (r: 0.362, 0.354, 0.332, P < 0.05). CONCLUSION: Combined detection of urinary RBP, beta(2)-MG, NAG and gamma-GT is a sensitive method for the diagnosis of early renal injury in the workers exposed to Hg.