Method for determining nitrogen dioxide in workplace air by ion-exchange chromatography / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To evaluate the method for collecting NO2 in workplace air using a solid adsorbent and determining the concentration of NO2 by ion-exchange chromatography.</p><p><b>METHODS</b>NO2 in workplace air was collected using sampling tubes filled with 13X molecular sieve soaked with triethanolamine, and the samples were desorbed with a certain concentration of triethanolamine solution to obtain NO2(-). NO2(-) was separated with an anion exchange chromatography column and quantified by a conductivity detector. The concentration of NO2 was determined based on the conversion coefficient of NO2 and NO2(-).</p><p><b>RESULTS</b>Different concentrations of NO2 (standard gas) was collected using the sampling tubes at different time points, and the sampling efficiency and desorption efficiency could reach more than 90%. The penetrating capacity of sampling tubes was more than 1.1 mg. The comparative test shows that there was no significant difference between the new method and national standard method (solution absorption) (P > 0.05). The samples could be stored at room temperature for more than 16 days. The calibration curve plotted in the new method was linear in the range of 0.1∼20.0 µg/ml, with a correlation coefficient of 0.9998; the detection limit was 0.01 µg/ml; the minimum detectable concentration was 0.05 mg/m(3) (V0 = 3.0 L).</p><p><b>CONCLUSION</b>This determination method meets the requirements of Guide for establishing occupational heath standards-Part 4 Determination methods of air chemicals in workplace (GBZ/T 210.4-2008) and shows obvious advantages for determination of NO2 in workplace air.</p>

Effect of Dimethyiformamide(DMF) on Histological Structure and Enzymes Activity in Testis of Mice / 环境与健康杂志

Objective To explore the effect of dimethylformamide(DMF)on the histological structure and enzymes activity in the testis of mice.Methods The KM male mice were treated with DMF by gavage at the doses of 0,0.5,1 and 2 g/kg respectively, once a day,for 30 consecutive days.On day 31,the mice blood samples were collected through eyes and then the mice were killed. Two mice were randomly selected in each group and one testicle was sampled to do the pathological examination,the other one for enzyme activity determination,including succinic acid dehydrogenase(SDH),lactate dehydrogenase(LDH)and acid phosphatase (ACP).Results Compared with the control group,all treated groups showed a significant decrease in body weight(P