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Tricalcium bis(orthophosphate) is an inorganic substance. Thus biological degradation is not relevant for the substance. In aquatic and in biological systems the substance dissociates to phosphate and calcium ions. When released to the environment a distribution in water and soil is most likely whereby the water solubility is inversely related to the pH value.

Calcium and phosphorus are both abundant natural elements that are ubiquitous in the aqueous and terrestrial environment. Calcium, the firth most abundant element, is an essential nutrient for higher plants, algae and animals. 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. The free calcium may interact with other ions, for example phosphorus. Like calcium, phosphate is also ubiquitous in natural waters 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. These same 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 stimulate the growth of water plants (macrophytes) and/or algae (phytoplankton) if they represent the growth-limiting factor.

Distribution of tricalcium bis(orthophosphate) to air is not likely. The substance is an inorganic salt and can thus be considered non-volatile. Due to the low vapour pressure is a significant release to the atmosphere not anticipated.

Bioaccumulation and secondary poisoning are not relevant for tricalcium bis(orthophosphate). Phosphate and Calcium are essential micronutrients for many organisms and the uptake and concentration of the ions in organisms regulated by a number of biological mechanisms.