Inductively coupled plasma-mass spectrometry (ICP-MS) is the most common technique for elements analysis at present. ICP-MS with high sensitivity and wide linear range can be applied to multi-elements analysis in blood and urine. This paper reviews the common means of sample pretreatment (direct dilution method and wet digestion method), the method for correction of mass spectral interference and non-interference, the main influence factors of analysis results, and provides an outlook of the application of ICP-MS in forensic toxicological analysis.
Body Fluids/chemistry* ; Humans ; Mass Spectrometry/methods* ; Metals, Heavy/urine* ; Microwaves ; Sensitivity and Specificity ; Specimen Handling/methods* ; Trace Elements/urine*

OBJECTIVEThis study aims to describe the distribution of 24 elements in urine of Shenzhen residents.

METHODSAccording to the principle of equal probability of selection method, in March 2011 to July, total 11 communities were chosen as the basic sampling unit in Shenzhen, with 1 to 2 communities in each of the municipal district. Then 75 families from each sampling unit were selected using systematic sampling method. In total, 2 200 subjects were chosen. 10-20 ml morning middle stream urine was collected, and then detected the concentration of Li, Be, Sr, Cd, Cs, Ta, Pb, V, Cr, Mn, Fe, Ni, Co, Cu, Zn, Sn, Sb, Te, As, Se, Ru, Na, Mg, K, and analysed the discrepancies between gender and among age groups.

RESULTSIn those 24 elements, the concentration of Na was highest, the medians( 5th percentile (P 5), 95th percentile (P 95)) were 2 845.78 (920.29, 5 974.53) mg/L; Be was lowest, the result was 0.10(0.01, 0.58) µg/L. Except macroelements of Na (2 921.97 (985.14, 6 201.51) mg/L), Mg (48.20(8.23, 132.41) mg/L), K (2 323.20(683.98, 5 657.47) mg/L), the content of Rb was highest, 3.31(9.82, 7.83) mg/L, followed by Zn, 454.54(113.90, 1 320.00) µg/L, the content of V, Cr, Mn, Se, Tl was pretty low, the median of those elements all less than 1.00 µg/L. Statistically significant differences were found between genders and among age groups in Pb, Fe, Se (gender: Z values were 4.51, 2.53, 4.00, all P values were <0.05; age groups: H values were 55.67, 129.42, 18.46, all P values were <0.05). The medians(P5, P95) were 2.04 (0.57, 5.31), 202.88 (48.66, 564.90), 49.68 (14.34, 150.91) µg/L. The values of male were 2.22 (0.71, 5.33), 212 (47.50, 567.29), 53.42 (16.20, 160.63) µg/L. And the results of female were 1.95 (0.51, 5.24), 193.69 (49.52, 562.31), 46.62 (12.65, 142.80) µg/L; the values of less than 17 years old subjects were 1.66 (0.38, 3.77), 106.13 (26.69, 459.81), 51.86 (15.86, 169.71) µg/L; the results were 1.96 (0.52, 5.08), 209.83(52.87, 577.81), 54.14 (15.14, 144.11) µg/L in the group of 18 to 40 years old; in the 41 to 65 years old group, the values were 2.29 (0.78, 5.85), 228.15 (67.74, 615.16), 46.62 (13.95, 143.57) µg/L, the results were 2.19 (0.65, 5.69), 195.92(55.17, 490.24), 43.16 (12.42, 155.36) µg/L in 66 years old and more group.

CONCLUSIONAmong these 24 elements in urine of Shenzhen residents, the Na concentration was highest, while Be was lowest. Elements (Pb, Fe, Se) differed with the condition of gender and age groups. So we should take all these factors into account to establish their reference values.

Adolescent ; Adult ; Aged ; China ; epidemiology ; Cross-Sectional Studies ; Female ; Humans ; Male ; Middle Aged ; Trace Elements ; urine ; Young Adult

Deficiencies of enzymes involved in amino acid metabolism frequently result in accumulation of toxic substances and subsequent organ damage. The brain, liver and kidneys are the most frequently affected organs. Acute symptoms are often associated with catabolic states that lead to the breakdown of endogenous proteins and the release of large amounts of amino acids. The clinical features result from the toxicity of the deficiency, and the extent of protein intake or endogenous amino acid release in protein compensation. Many disorders of this group are recognised by neonatal screening with tandem MS. Most aminoacidopathies are caused by deficiencies of cytosolic enzymes and are recognised by amino acid analysis in plasma (or urine). Treatment usually involves(a) protein restriction, (b) supplementation of amino acids with unimpaired metabolism as well as trace elements, and (c) specific measures for detoxification if indicated. Treatment is not restricted to childhood but usually must be continued throughout life.
Amino Acids ; Brain ; Compensation and Redress ; Cytosol ; Homocystinuria ; Infant, Newborn ; Kidney ; Liver ; Maple Syrup Urine Disease ; Metabolism* ; Neonatal Screening ; Phenylketonurias ; Plasma ; Trace Elements

Animals ; Bone and Bones ; drug effects ; Copper ; pharmacology ; therapeutic use ; Fluoride Poisoning ; prevention & control ; Fluorides ; blood ; toxicity ; urine ; Lipid Metabolism ; drug effects ; Molybdenum ; toxicity ; Rabbits ; Trace Elements ; pharmacology ; therapeutic use