Abstract: A case study was made on the environmental issues from the contamination discharging of a 2.0×10⁵ t·yr^-1 maize-based monosodium glutamate production in a company of Tongliao City,Inner Mongolia.The results showed that monosodium glutamate production could easily induce water pollution which was most serious at fermentationextraction phase.At this phase,the SS,COD_Cr and BOD₅ in discharged wastewater were up to 3.0×10³,2.5×10⁴ and 1.2×10⁴ mg·L^-1,respectively.The main air pollutants discharged included dust,H₂S,and the soot and SO₂ from sirocco furnaces.The concentration of discharged H₂S could be up to 7.0×10⁴ mg·m^-3.As for solid wastes pollution,the main pollutants were starch sinking dreg,fibre dreg,gluten,fine dreg,embryo dreg,and broken maize dreg.Through the systematic control of wastewater and air discharge and the comprehensive utilization of solid wastes,the contamination discharging from this company was achieved to the relevant national standards of this country.

Key words: UV-B radiation, Acer davidii, Physiological response