ABSTRACT
<p><b>OBJECTIVE</b>To explore the relationship between different components of fine particulate matter (PM2.5) emitted from coal combustion and their cytotoxic effect in the vascular endothelial cells.</p><p><b>METHODS</b>Coal-fired PM(2.5) was sampled using a fixed-source dilution channel and flow sampler. The sample components were analyzed by ion chromatography and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The PM(2.5) suspension was extracted using an ultrasonic water-bath method and then human umbilical vein endothelial cells (EA.hy926) were treated with various concentrations of the PM(2.5) suspension. Cell proliferation, oxidative DNA damage, and global DNA methylation levels were used to measure the cellular toxicity of PM(2.5) emitted from coal combustion.</p><p><b>RESULTS</b>Compared to other types of coal-fired PM(2.5) preparations, the PM2.5 suspension from Yinchuan coal had the highest cytotoxicity. PM(2.5) suspension from Datong coal had the highest toxic effect while that from Yinchuan coal had the lowest. Exposure to coal-fired PM(2.5) from Jingxi coal resulted in lower 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels. At the same dose, PM(2.5) emitted from coal combustion could produce more severe DNA impairment compared to that produced by carbon black. Cell survival rate was negatively correlated with chloride and potassium ions content. The 5-methylcytosine (5-mC) level was positively correlated with Mn and negatively correlated with Zn levels. The 8 OHdG% level was positively correlated with both Mn and Fe.</p><p><b>CONCLUSION</b>PM(2.5) emitted from coal combustion can decrease cell viability, increase global DNA methylation, and cause oxidative DNA damage in EA.hy926 cells. Metal components may be important factors that influence cellular toxicity.</p>
Subject(s)
Cell Proliferation , Coal Ash , Toxicity , DNA Damage , DNA Methylation , Human Umbilical Vein Endothelial Cells , Toxicity TestsABSTRACT
<p><b>OBJECTIVE</b>To explore the toxicity of joint exposure to diazinon, propoxur and bisphenol A on phagocytosis.</p><p><b>METHODS</b>Flow cytometer was employed to detect the influence of diazinon and bisphenol A, propoxur and bisphenol A in mixture (mixed according to ratio of IC(50)) on mouse macrophage RAW264.7 cells' function to phagocyte fluorescent microspheres, adopting the percentage of phagocytic cells (PP) and the phagocytic index (PI) as measurement indicators. The final concentrations of mixture of diazinon and bisphenol A were (0.4 + 0.1), (3.6 + 0.7), (36.2 + 7.2), (43.4 + 8.7), (52.1 + 10.4), (62.5 + 12.5), (75.0 + 15.0) µg/ml; while those of mixture of propoxur and bisphenol A were (0.2 + 2.0 × 10(-2)), (2.4 + 0.2), (23.7 + 2.0), (35.6 + 3.0), (53.3 + 4.4), (80.0 + 6.7), (120.0 + 10.0) µg/ml. Then based on the dose-response relationship, a 2 × 2 factorial design was then carried out among different doses of mixture with statistical significance to statistically evaluate the interaction between diazinon and bisphenol A, propoxur and bisphenol A.</p><p><b>RESULTS</b>After the joint exposure, compared to the control group (PP = (23.6 ± 2.2)%; PI = 0.36 ± 0.03), any dose of the mixture of diazinon and bisphenol A ((52.1 + 10.4), (62.5 + 12.5), (75.0 + 15.0) µg/ml) could significantly increase the levels of PP ((29.0 ± 1.4)%, t = 3.89, P < 0.05; (30.2 ± 2.3)%, t = 4.74, P < 0.05; (35.0 ± 3.4)%, t = 8.21, P < 0.05) and PI (0.43 ± 0.03, t = 3.86, P < 0.05; 0.41 ± 0.02, t = 2.95, P < 0.05; 0.46 ± 0.03, t = 5.34, P < 0.05); while that of propoxur and bisphenol A ((35.6 + 3.0), (53.3 + 4.4), (80.0 + 6.7), (120.0 + 10.0) µg/ml) reduced the levels of PP ((20.6 ± 1.1)%, t = -3.00, P < 0.05; (20.2 ± 1.0)%, t = -3.42, P < 0.05; (19.4 ± 1.3)%, t = -4.23, P < 0.05; (18.8 ± 2.1)%, t = -4.81, P < 0.05) and PI (0.31 ± 0.01, t = -4.75, P < 0.05; 0.31 ± 0.01, t = -4.58, P < 0.05; 0.30 ± 0.01, t = -4.92, P < 0.05; 0.27 ± 0.02, t = -7.80, P < 0.05) on the contrary. The 2 × 2 factorial design was carried out between the mixture of diazinon (60.0 µg/ml; PP = (28.5 ± 3.4)%; PI = 0.49 ± 0.07) and bisphenol A (12.0 µg/ml; PP = (35.7 ± 2.7)%; PI = 0.67 ± 0.07), and the mixture of propoxur (48.0 µg/ml ; PP = (28.1 ± 2.2)%; PI = 0.48 ± 0.04) and bisphenol A (4.0 µg/ml; PP = (34.4 ± 2.7)%; PI = 0.59 ± 0.07). The mixture of diazinon and bisphenol A (PP = (30.4 ± 1.4)%, F(interaction) = 6.22, P < 0.05; PI = 0.53 ± 0.03, F(interaction) = 7.35, P < 0.05) and the mixture of propoxur and bisphenol A (PP = (27.5 ± 4.1)%, F(interaction) = 4.56, P < 0.05; PI = 0.46 ± 0.08, F(interaction) = 11.13, P < 0.05) both showed a significant antagonistic interaction on phagocytosis of RAW264.7 cell.</p><p><b>CONCLUSION</b>It is suggested that the interactions between diazinon & bisphenol A and propoxur & bisphenol A both played the antagonistic role on phagocytic function of macrophages in vitro.</p>