An analysis of characteristics of exposure to nanoparticles in a workplace manufacturing iron oxide nanoparticles / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the characteristics of exposure to iron oxide nanoparticles in workplace.</p><p><b>METHODS</b>The real-time particle number (NC), surface area (SAC), and mass (MC) concentrations of nanoparticles were measured in various locations of a selected workplace manufacturing iron oxide nanoparticles. The collected particles were analyzed for morphology and elemental composition.</p><p><b>RESULTS</b>The average NCs and SACs in milling site (16,566 pt/cm3, 106.082 µm2/cm3), packaging site (12,386 pt/cm3, 89.861 µm2/cm3), shipping site (13,808 pt/cm3, 102.071 µm2/cm3), and product storage room (17,192 pt/cm, 115.044 µm2/cm3) of the yellow powder (α-Fe2O3 . nH2O) were all significantly higher than the workplace background concentrations (11,420 pt/cm3, 85.026 µm2/cm3) (all P<0.05). The NC was highly correlated with the SAC (r= 0.784), while both NC and SAC were loosely correlated with the MC (r1=0.323, r2=0.331). Scanning electron microscopy revealed a spindle-like shape of the iron oxide nanoparticle; the chemical composition of the collected particles contained 19.33 weight percent iron (Fe).</p><p><b>CONCLUSION</b>The milling site and product storage room of the yellow powder are exposed to a higher concentration of nanoparticles, which are mainly composed of iron oxide nanoparticles. The NC is highly correlated with the SAC.</p>

Toxicity of intragastrically administered N, N-dimethylformamide in female Wistar rats / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the toxicity of intragastrically administered N, N-dimethylformamide (DMF) in female Wistar rats, and to provide experimental data for the overall evaluation of DMF toxicity under different ways of exposure.</p><p><b>METHODS</b>Forty female Wistar rats weighing 150∼180 g were randomly divided into four groups: control group (treated with water) and three DMF exposure groups with doses of 50 mg/kg, 100 mg/kg, and 200 mg/kg. After oral administration of DMF once a day for 14 consecutive days, the rats were weighed and sacrificed. The liver, kidney, brain, and uterus were weighed to calculate organ indices. The pathological changes in the liver were examined by HE staining. The protein expression of HSP70 in the liver, kidney, and brain was determined. Finally, peripheral lymphocytes were collected from the arteria cruralis to determine DNA damage by comet assay.</p><p><b>RESULTS</b>Fourteen days after DMF exposure, the body weight and organ indices of the kidney, brain, and uterus showed no significant changes. However, the liver index showed concentration-dependent increase in all DMF exposed groups (3.52±0.21, 3.55±0.13, and 3.88±0.22 in the low-, medium-, and high-dose groups, respectively), as compared with the control group (3.24±0.28) (P < 0.05 or P < 0.01). The pathological damage in the liver also showed a concentration-dependent manner. Inflammatory cell infiltration and granular degeneration in centrilobular hepatocytes were observed in the high-dose group. No significant change in protein expression of HSP70 was observed in the liver, kidney, or brain of DMF-exposed rats (P > 0.05). DNA damage was induced by DMF, and the DNA percentage of lymphocyte comet tail, average tail length, and tail moment in exposed groups were all significantly increased as compared with the control group (P < 0.05 or P < 0.01).</p><p><b>CONCLUSION</b>Gavaged DMF can induce liver injury and DNA damage in lymphocytes in rats 14 days after administration. There is no significant change in protein expression of HSP70 in the liver, brain, or kidney after DMF exposure.</p>

Effect of Tri-n-butyltin on Total Oxyradical Scavenging Capacity in Mice Viscera Tissues / 环境与健康杂志

Objective To investigate the oxidative stress caused by tri-n-butyltin (TBT) in mice. Methods 24 male NIH mice were chosen and the different doses of TBT were given per os for 24 h acute toxic test, meanwhile set the control group of 0.9% sodium chloride and 13% ethanol. The TOSC of heart, brain, lung, liver and kidney homogenates were detected by gas chromatography. Results After 24 h TBT exposure, TOSC of all viscera tissues was increased and this change was significant in the heart and brain, in every dose level, compared with the control (P