Soil microbial and enzyme properties as affected by long-term exposure to phthalate esters

In this study, an isothermal microcalorimetry was used to demonstrate the long-term impact of dimethyl phthalate (DMP), dipropyl phthalate (DBP), dioctyl phthalate (DOP) and dicyclohexyl phthalate (DEHP) on the soil microbial activity. Generally, the toxicity order of four phthalate esters (PAEs) is DBP>DMP>DOP>DEHP. The PAEs show inhibitory effect when the soil was exposed to PAEs for 10 days and the PAEs will have a small stimulate effect after 30 days, and then the PAEs inhibit the soil microorganisms again. The effect of PAEs on soil microbial activity is almost the same as those on urease activity.