Abstract: Based on the simulation study, pot experiment and field experiment with labelled and unlabelled hydroquinone and consulting foreign literatures, this paper discussed the direction in which hydroquinone has gone, the eff ects of hydroquinone on soil biological activity and its environmental effect when applicated with minor amount over long period of time. It is concluded that minor amount of hydroquinone entered into soil with hydroquinone containing urea fertilizer will not accumulate in soil and plant, and not enterinto underground water and atmosphere. In soil, hydroquinone will be involved in the formation of humic substances or photooxidated,ozonated and biodegrated, forming dibasic acids through the break of benzene ring. In plant, it will be assimilated by the conjugation of glucoside. It has a promoting or inhibitory effect on the activity of soil enzymes at the early stage of application but assuaged or disappeared with time. Therefore, hydroquinone used as an urease inhibitor will not induce the pollution of environment and the poising of food chain.

Key words: Urease inhibitor, Hydroquinone, Environmental effect