Many eco-toxicity tests have been undertaken on a wide range of test species by a variety of independent academic and government research institutions over the past ten years. Collectively, these reports demonstrate that Phoslock has a very low toxicity and is safe to use in naturally occurring environmental conditions at recommended dosages. A detailed overview of these studies ( 800 Kb) has been produced by the Technical Department of Phoslock Water Solutions in Australia. In addition to this overview, several of the most important eco-toxicity assessments conducted by external agencies and institutions can also be downloaded from the Publications Page.
Furthermore, over the past four years, more than 100 Phoslock applications have been completed in over 20 countries with no evidence of toxicity having been observed in any of the species of aquatic flora and fauna that have been tested.
Human Toxicity Assessment
Several toxicity assessments on the effects of both Phoslock and lanthanum chloride on human health have also been undertaken and the results have been analysed and interpreted in an Overview Document prepared by PWS' Technical Department in Australia.
Bentonite is not considered toxic to humans and in many countries is an approved food additive. In contrast to other products used in the water industry to bind phosphate such as aluminium, lanthanum is used as a beneficial agent to human health. Lanthanum carbonate is approved as a medicine in Australia, Europe and the US under the trade name, Fosrenol. This product is used as a phosphate binder to treat hyperphosphatemia in patients with chronic kidney disease who are undergoing dialysis and is typically prescribed in dosages of between 1,500 and 3,000 mg per day. These dosages are far in excess of the amount of lanthanum that could possibly be ingested by humans from water in a reservoir that has been treated by Phoslock (ref Overview Document, p9).
Detailed information on the clinical trials undertaken on lanthanum carbonate for the approval of Fosrenol is available on the manufacturers' website (www.fosrenol.com).
Definition of toxicity
Toxicity is the degree to which something is able to produce illness or damage to an exposed organism. Toxicity can refer to the effect on a whole organism, or to a substructure, such as a cell (cytotoxicity) or an organ (organotoxicity). A central concept of toxicology is that effects are dose-dependent: everything is toxic after a certain dose. The dose differs depending on the substance and on the receiving organism, therefore results are mostly expressed as mg substance per kg body mass and per day.