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Experimental data on the toxicity of dicalcium pyrophosphate to soil organisms are not available. However, the chemical safety assessment does not indicate the need to investigate further the effects on terrestrial organisms. Based on the aquatic hazard assessment toxic effects of the substance on terrestrial organisms are not expected. The substance is not expected to bioaccumulate or to be chronically toxic. On contact with water the substance dissociates to calcium and phosphate ions that are ubiquitous in the terrestrial environment.

Calcium, the firth most abundant element, is an essential nutrient for higher plants, algae and animals. It is a major component of bones but also important constituent of the exoskeleton of invertebrates and cell walls of plants. Calcium occurs only in compound form in the environment. It is expected to adsorb to clay and organic matter in soil and thus to be relatively immobile in natural soils. However, the mobility strongly depends on the cation-exchange capacity of the soil. The calcium concentration increases with the CEC of soils. The availability of free calcium increases with soil pH.

Like calcium, phosphate is also ubiquitous in the environment and an essential micronutrient for many organisms. Inorganic phosphates will dissociate to soluble orthophosphate (PO43-) in sewerage systems, sewage treatment plants and in the environment. Orthophosphates are also formed by natural hydrolysis of human urine and faeces, animal wastes, food and organic wastes, mineral fertilisers, bacterial recycling of organic materials in ecosystems, etc. The phosphate anion in soil will precipitate with Fe, Al or Ca cations. Thus the mobility of phosphate in soil is limited. Phosphates are bio-assimilated by the bacterial populations and the aquatic plants and algae found in these different compartments and are an essential nutrient (food element) for plants, and terrestrial invertebrates.

Thus, detrimental effects on terrestrial organisms are not expected due to the absence of acute aquatic toxicity, the low bioaccumulation potential and the fact that both ions are essential micronutrients.