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用￣（１４）Ｃ－氢醌和￣（１５）Ｎ－尿素为示踪剂，通过棕壤盆栽试验，研究了氢醌在土壤中的分布、存在形态及迁移机制。氢醌的残留量随土壤垂直深度的增加而增多，平均土壤残留量为０．０４１ｍｇ／ｋｇ土。由于土壤理化和生化作用，约有１３％的氢醌分解成ＣＯ＿２和水。残留于土壤的￣（１４）Ｃ，４９％进入土壤高分子有机化合物，不能再被溶剂所提取。实验测定了水稻对氢醌的吸收、分配和代谢。糙米和茎叶中氢醒的含量分别为０．０７ｍｇ／ｋｇ和０．０５ｍｇ／ｋｇ。水稻体内￣（１４）Ｃ－氢醒的９０％以上能破代谢和降解。实验表明，外源氢醌参加了植物的碳代谢，并促进了土壤尿素Ｎ的利用。根据实验结果，计算了长期使用长效尿素后土壤中氢醌残留量极限值是０．０４４ｍｇ／ｋｇ土。该值远小于美国规定的土壤氢醌残留量标准中，保障人体健康所允许的最高临界值０．２０ｍｇ／ｋｇ土，结论是长期使用长效尿素是安全的。
With 14 C-hydroquinone and 15 N-urea as tracers, the distribution, existing morphology and migration mechanism of hydroquinone in soil were studied by pot experiments in brown soil. Residue of hydroquinone increased with the vertical depth of soil, and the average soil residual amount was 0.041mg / kg soil. About 13% of hydroquinone decomposes into CO_2 and water due to soil physicochemical and biochemical effects. Residues in the soil ~ (14) C, 49% into the soil organic polymer compounds, can no longer be solvent extraction. The experiment measured the absorption, distribution and metabolism of hydroquinone in rice. Hydrogen content in brown rice and stems and leaves was 0.07 mg / kg and 0.05 mg / kg, respectively. Rice body ~ (14) C-hydrogen wake up more than 90% can be broken metabolism and degradation. Experiments show that exogenous hydroquinone participates in plant carbon metabolism and promotes the utilization of soil urea N. According to the experimental results, the limit of hydroquinone residues in soils after long-term use of long-acting urea was calculated as 0.044 mg / kg soil. This value is much smaller than the soil hydroquinone residue standard set by the United States to guarantee the maximum allowable threshold of 0.20 mg / kg soil for human health. The conclusion is that long-term use of long-acting urea is safe.