China starts to remediate heavy metal polluted soil

Chinese Ministry of Finance (MOF) recently announced the start of remediation of heavy metal polluted soil, which was initiated in Hunan Province, China. Relevant statistics has revealed 20 million hectares of cultivated land polluted by heavy metals which seriously threatens the safety of farm product, attributable to the use of large amount of fertilizer and pesticide, as well as caused by the contaminations to the environment.

The activation and deactivation are the 2 methods commonly adopted in developed countries to remediate heavy metal polluted soil. Activation aims to increase the dissolvability and mobility of heavy metals, which via soil flushing can transfer the heavy metals in soil’s solid phase into soil’s hydraulic phase and then to facilitate the reclamation of waste water containing heavy metals; deactivation decreases the mobility and bioavailability of heavy metals so as to reduce crop’s absorption of heavy metals.

According to an expert of Chinese Academy of Agricultural Sciences, it may be more preferable for Chinese agriculture to grow plants which can absorb heavy metals and to treat same by centralized disposal, or to apply organic fertilizer which can deactivate heavy metals, or to use soil improvers. These measures are more acceptable to farmers and can be applied more easily.

So far the Chinese company Chengdu NewSun Crop Science has released its soil improver products for remediation of heavy metal polluted soil. A few days ago the soil adjuster “Gekang” developed jointly by Chinese Academy of Agricultural Sciences and Chengdu New Sun Crop Science Ltd passed the field test, proving that the use of the product in moderately cadmium polluted soil could enable the conformity of rice seed to the food safety standard in respect of cadmium content.