Comparison of heavy metal limits for chemical fertilizers in China,EU and US and enlightenments

This paper briefly introduced the work out procession and the heavy metal limits in chemical fertilizers in some states of the United States and the Europe Union countries, and pointed out the shortages existed in the standards and the working out processions in China. The heavy metal limit standards for chemical fertilizers in China are fertilizer type specific, and greatly different among the fertilizers. The heavy metal limit standards are issued by different departments, including national and industrial standards. Some of the national standards for simple fertilizers and compound fertilizers lack heavy metal limits, but that for water-soluble fertilizers has quite strict limits for heavy metals. The limit standards for heavy metals do not have adequate theoretical and experimental data support, and have no necessary explanations for the basis of establishment after publication. The heavy metal limits in the United States are set up considering both the phosphate and micronutrient fertilizers and their application amounts. Several institutions (e.g. USEPA) in the United State made the standards using the evaluation models for the risks assessment of harmful elements in fertilizers for human health, and referring the data from long-term local field trials and the surveys for risk assessments in foods . The Association of American Plant Food Control Officials (AAPFCO) has proposed limits for heavy metals in chemical fertilizers based on these acceptable limits, and some states in the US are implementing the heavy metal standards based on their state laws and regulations. The EU countries do not have uniform heavy metal limits in chemical fertilizers, and they manage the fertilizers by their own laws and regulations. The standard settings for heavy metal limits relate to various benefits and public welfare issues in fertilizer production and application, soil health, water environmental protection, food safety, deserving our careful thinking and investigation. Suggestion: China should refer to the standard setting methods in developed countries to establish assessment system for hazard risk of heavy metals. The heavy metal limits should consider fertilizer types such as macronutrient, secondary and micronutrient fertilizers, and make one standard for all chemical fertilizers in China. Meanwhile, by referring to the existing research results from foreign countries, it is better to jointly formulate heavy metal limit standards for chemical fertilizers suitable for our national conditions by various departments based on investigation and long-term fixed experiment.