Determination of cobalt and tungsten in human urine by inductively coupled plasma mass spectrometry / 中华劳动卫生职业病杂志

Objective: To establish a inductively coupled plasma mass spectrometry method for the determination of trace cobalt and tungsten in human urine. Methods: The authors used 1% nitric acid solution as diluent in October-December 2021, the sample dilution factor and internal standard element were optimized by single factor rotation experiment, and the difference between the working curve and the standard curve was compared. Results: The method uses working curve to determine cobalt and tungsten in urine, the linear range of this method was 0.0~10.0 μg/L, the correlation coefficient was 0.999 9, the detection limits respectively were 0.005 μg/L (cobalt) and 0.09 μg/L (tungsten), the recoveries of samples respectively were 87.0%~100.2% (cobalt) and 89.4%~104.8% (tungsten), the relative standard deviations respectively were 0.4%~4.4% (cobalt) and 0.6%~3.8% (tungsten) . Conclusion: A simple and rapid method for determination of cobalt and tungsten in urine has been established. This method has the advantages of simple operation, high sensitivity, low detection limit and good stability. It is suitable for determination of cobalt and tungsten in urine of all kinds of people.

Detection of chloroprene in human blood by headspace gas chromatography / 中国职业医学

OBJECTIVE: To establish a detection method for chloroprene in human blood by headspace gas chromatography.METHODS: The blood sample was placed directly in the headspace bottle,after the head space automatic sampling,the target object was detected by gas chromatography with electron capture detector,quantified by external standard method.RESULTS: The good linearity range of chloroprene was 0. 00-160. 00 μg / L,and the correlation coefficient was 0. 999 4. The detection limit was 0. 10 μg / L and the minimum detectable concentration in blood samples was 0. 10 μg / L. The with-run relative standard deviation( RSD) was 1. 38%-1. 91%,and the between-run RSD was 2. 11%-3. 08%. The average recovery rate was 89. 00%-93. 88%. CONCLUSION: The method has the features of high sensitivity,wide linear range and simple sample processing,which was suitable for efficient detection for large quantity of samples.

Determination of dimethyl ether in workplace air with gas chromatography / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To develop determination of dimethyl ether in workplace air by GC.</p><p><b>METHODS</b>Dimethyl ether were sampled with solvent desorption active carbon tube. The sampled carbon tube were desorbed by carbon tetrachloride, Elite-WAX column was used with temperature programmed from 40 to 90 degrees C, and the carrier gas programmed from 1.4 - 2.5 ml/min.</p><p><b>RESULTS</b>There was a good linearity (r = 0.9999) over the concentration of 0-63.91 microg/L, detection limit can reach 0.75 microg/ml.</p><p><b>CONCLUSION</b>This method proved to be accurate and sensitive, to meet the determination of the dimethyl ether in workplace air.</p>

Determination of hydrogen selenide in workplace air with atomic fluorescence / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To determined hydrogen selenide in workplace air with atomic fluorescence.</p><p><b>METHOD</b>Hydrogen selenide were sampled with 0.1 mol/L sodium hydroxide solution in multi-hole absorbing tubes. The sampled absorbing solution were digested with (9+1) nitric acid/perchloric acid. The selenide in sample were reduced by potassium borohydride in 5.0% hydrochloride solution and determined with atomic fluorescence.</p><p><b>RESULTS</b>There was a good linearity (r=0.9999) over the concentration of 0-150 microg/L, The precision of low, middle and high concentration were 3.1%, 7.4% and 6.7%, respectively. The sample collection rate can reach 99%.</p><p><b>CONCLUSION</b>The method was accurate and sensitive to detect hydrogen selenide in workplace air.</p>

The improvement of determination method of carbon disulfide in workplace air with gas chromatography / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>Establishment of determination method of carbon disulfide in charcoal tube with low toxicity solvents desorption-gas chromatography.</p><p><b>METHODS</b>Four types of solvent with low toxicity are applied respectively as substitution of benzene to desorb the carbon disulfide in samples of charcoal tube. The signal strength and desorption efficiency of the detector are compared by using different solvents.</p><p><b>RESULTS</b>Chloroform has been considered as the best alternative solvent of benzene. Carbon disulfide has a good linearity (R = 0.9997) over the concentration of 0 ∼ 54.7 µg/ml, detection limit can reach 0.2 µg/ml. When the sampling volume is 3.0 L, the minimum detectable concentration is 0.07 mg/m(3).</p><p><b>CONCLUSION</b>With the use of chloroform, the health hazard to laboratory personnel and environment pollution as well as the costs of experiments are reduced.</p>

The optimization of 2-thiothiazolidine-4-carboxylic acid back extraction in urine and determination by HPLC / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>Establishment of determination method of 2-thiothiazolidine-4-carboxylic acid (TTCA) in urine with HPLC.</p><p><b>METHODS</b>A volume of 0.5 ml hydrochloric acid (2 mol/L) and 0.5 ml pure water was added into 1 ml urine, and then extracted by 4 ml of diethyl ether by shaking for 2 min. Remove the water phase in a tube with plug and extract again, mix the two extraction diethyl ether together, take 4 ml by adding 2 ml borax-monopotassium phosphate buffer and shaking for 2 min to extract, then take the water phase to detect. A C(18) column and UV detector were used for separating and detecting. The wavelength was 273 nm, the flow rate was 1.0 ml/min, and the injection volume was 20 µl.</p><p><b>RESULTS</b>TTCA has a good linearity (r = 0.9995) over the concentration of1 1 ∼ 10 µg and the minimum detectable concentration of TTCA in urine was 0.1 µg/ml. The within-day precision (RSD) were 8.4%, 3.0% and 1.7%, the between-day precision (RSD) were 11%, 3.8%, 1.9%, respectively. The extraction recovery were between 80% ∼ 102%.</p><p><b>CONCLUSION</b>The method was accurate and sensitive to detect TTCA in urine.</p>

The rervising of biological exposure index for carbon disulfide exposuring / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the biological exposure index of carbon disulfide in China.</p><p><b>METHODS</b>High-performance liquid chromatography (HPLC) was used to detect the levels of 2-thiothiazolidine-4-carboxylic acid (TTCA) in the urine of the workers after working shift end, Gas chromatography was used to detect the concentrations of the carbon disulfide in the workplace air. The relationship between the urine TTCA levels and the concentrations of the carbon disulfide was analyzed, the biological exposure index and judgement result from PC-TWA were compared.</p><p><b>RESULTS</b>The levels of TTCA in urine of workers occupationally exposed to carbon disulfide were closely and positively related with the concentrations of the carbon disulfide in the workplace air. The regression equation was Y = 0.265X - 0.165, The biological exposure index of carbon disulfide were calculated by regression equation according to occupational exposure limits of carbon disulfide in China.</p><p><b>CONCLUSION</b>The biological exposure index of CS(2) in China might be revised for 1.2 mg/g Cr.</p>

The surface biomarkers of sputum cells in coal mine workers and patients with pneumoconiosis / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore the significance of intercellular adhesion molecule -1 (CD54 or ICAM-1), epidermal growth factor receptor (EGFR) and platelet-derived factor (PDGF) in sputum cells of workers exposed to dust and patients with pneumoconiosis for the early diagnosis of pneumoconiosis.</p><p><b>METHODS</b>The subjects included 62 workers exposed to dusts, 51 workers not exposed to dusts, 22 patients with pneumoconiosis and 10 healthy controls. The respiratory sputum technique was used to collect the sputum samples and the biomarkers (ICAM-1, EGFR and PDGF) of the sputum samples were detected with the sputum samples.</p><p><b>RESULTS</b>When the exposure group was compared with non-exposure group, there were no significant differences of surface biomarkers (ICAM-1, EGFR and PDGF) in sputum cells (neutrophil leucocytes, macrophages, lymphocytes and acidophilic/basophil leucocytes). As compared with other workers exposed to dusts, the surface CD54 and EGFR expression levels increased significantly and the surface PDGF expression level decreased significantly in workers exposed to dusts for 10 years (P<0.05). As compared with controls, the CD54 and EGFR expression levels of sputum cells increased significantly and the PDGF expression level of sputum cells decreased significantly in patients with pneumoconiosis at the stages of I and II + mI (P<0.05).</p><p><b>CONCLUSION</b>The expression levels of the surface CD54, EGFR and PDGF of sputum cells in workers exposed to dusts and patients with pneumoconiosis changed, which may be useful for early detecting pneumoconiosis.and patients is changed, which may be meaningful for early detection of pneumoconiosis.</p>