RESUMEN
The occurrence and removal of benzene, toluene, ethylbenzene, xylenes, styrene and isopropylbenzene (BTEXSI) from 6 textile dyeing wastewater treatment plants (TDWTPs) were investigated in this study. The practical capacities of the 6 representative plants, which used the activated sludge process, ranged from 1200 to 26000 m(3) d(-1). The results indicated that BTEXSI were ubiquitous in the raw textile dyeing wastewater, except for isopropylbenzene, and that toluene and xylenes were predominant in raw wastewaters (RWs). TDWTP-E was selected to study the residual BTEXSI at different stages. The total BTEXSI reduction on the aerobic process of TDWTP-E accounted for 82.2% of the entire process. The total BTEXSI concentrations from the final effluents (FEs) were observed to be below 1 µg L(-1), except for TDWTP-F (2.12 µg L(-1)). Volatilization and biodegradation rather than sludge sorption contributed significantly to BTEXSI removal in the treatment system. BTEXSI were not found to be the main contaminants in textile dyeing wastewater.
Asunto(s)
Hidrocarburos Aromáticos/análisis , Residuos Industriales/análisis , Industria Textil , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Benceno , Biodegradación Ambiental , Aguas del Alcantarillado , Textiles , Tolueno , Eliminación de Residuos Líquidos/métodos , XilenosRESUMEN
To evaluate the significance of antithyroid antibodie levels, five hundred and twenty-six patients with thyroid diseases and 292 health subjects from Yuci District, Shanxi Province, China, were studied. Serum levels were determined for thyroid hormone receptor antibody (TRAb), microsomal antibody (TMAb) and thyroglobulin antibody (TGAb). Among patients, the percentages for nodular goiter and thyroid adenoma, Graves' disease, and Hashimoto's thyroiditis are 44.1%, 19.6% and 17.7%, respectively. The ratios of female to male were 2.0 to 15.6. Antibody-positive patients for TMAb, TGAb and TRAb were detectable as 94.6%, 76.3% and 20.4% for Hashimoto's thyroiditis, and 40.0%, 30.0% and 90.3% for Graves's disease. In conclusion, the high levels of the TRAb in Graves' disease, and those of the TGAb/TMAb in Hashimoto's thyroiditis and idiopathic hypothyroidism are meaningful for characterizing the epidemiological basis of the diseases and for using as prognostic indicators for the relapse in individual patients.