Effects of Reclaimed Water Irrigation on Grain Quality and Endogenous Estrogen Concentrations of Winter Wheat

Reclaimed water irrigation can effectively alleviate the shortage of water resources in arid and semi-arid areas; however, reclaimed water contains organic pollutants that may enter the agricultural production environment through irrigation, such as endogenous estrogens, so people have always paid attention to the safety of reclaimed water irrigation. In this paper, we studied the effects of reclaimed water irrigation, groundwater irrigation, and alternating irrigation of the two water sources on grain quality, as well as endogenous estrogen concentrations of winter wheat and topsoil in the North China Plain during 2015-2016. The results show that the concentrations of crude protein, total soluble sugar, crude ash, crude starch, and reduction-type vitamin C (reduction-type VC) in the winter wheat grains were 12.5-16.4%, 0.85-2.15%, 1.85-3.28%, 61.5-75.0%, and 4.9-16.0 mg/kg, respectively. There were no significant differences in these quality indexes among the irrigation treatments (p > 0.05). The concentrations of endogenous estrogen in the surface soil and winter wheat grain under all irrigation treatments were 0.34-4.01 mu g/kg and below the limits of detection (ND)-3.71 mu g/kg, respectively. There were no significant differences in the concentrations of endogenous estrogen in the soil and wheat grain among the different irrigation treatments (p > 0.05). The bioconcentration factor (BCF) of the endogenous estrogen in the soil-winter wheat system was 0.08-1.90, and there was no significant difference in the BCF among the irrigation treatments (p > 0.05). Compared with groundwater irrigation, reclaimed water irrigation did not significantly affect endogenous estrogen concentrations in the soil and winter wheat, as well as the bioconcentration factors.