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Views: 563 Author: VV Publish Time: 2016-10-26 Origin: Rech Chemical Co. LTD
In the production and processing process,zinc sulfate products more or less will involve in heavy metal. Therefore, our country also haves strict standards for this industry. The national standard label is for GB/T 23349-2009 and its heavy metals national index in agriculture grade zinc sulphate as bellow:
| Items | Index |
| The mass faction of Arsenic and compound（As）% ≦ | 0.0050 |
| The mass faction of cadmium and compound(Cd)% ≦ | 0.0010 |
| The mass faction of lead and compound (Pb)% ≦ | 0.0200 |
| The mass faction of chromium and compound (Cr）% ≦ | 0.0500 |
| The mass faction of mercury and compound (Hg) % ≦ | 0.0005 |
This standard above not only sets the upper limit of the heavy metal content, but also not allow to add dye, colorant and other illegal additives in fertilizers that may be harm to environment, crop growth and the quality and safety of agricultural products. This standard is not only for agriculture grade zinc sulphate, also for all agriculture grade fertilizers and magnesium sulphate produced and sold in China.
