556c8ddb_rganic_Rules_and_Certification__1
[0] Fertilization, substrates, heavy metals - UK Soil Association Organic Standards 2005 [2] Soil Association standards contain recommendations and restrictions on heavy metal levels for topsoil and manure, whereas EU Regulation 2092/91 only mentions heavy metal levels for household wastes and phosphate fertilizers. [3] High levels of heavy metals in soil can be toxic to crop plants, and can be taken up by crops and cause health problems to people. High levels of heavy metals in manures can lead to accumulation in the soil to which they are applied. This could lead to longer-term problems for crop yields and safety. Soil Association restrictions on heavy metal in soils and manures are intended to minimise these associated risks. [1] 
Best practice recommendations are explained regarding heavy metal in soil. Maximum permitted levels of heavy metals are specified for topsoil and manure. Soil Association standards explain that soil heavy metal concentrations need to be maintained at healthy levels and that nutrient inputs should not increase concentrations above acceptable levels. This is followed by a table specifying the maximum permitted levels of heavy metals (in total dry matter) for soils and manures. These include zinc, chromium, copper, lead, nickel, cadmium, mercury and arsenic. (Soil Association Organic Standards. Paragraph 4.9.2.)
Custom php script - Organic Rules and Certification
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