Evaluation of the EPA exposure assessment for phosphoric acid

The philosophy of this paper is that the Environmental Protection Agency's (EPA) 1990 exposure assessment for phosphoric acid is not based on sound science and therefore does not accurately characterize the eutrophication potential of phosphoric acid releases from Toxic Release Inventory (TRI) reporting facilities. This error propagates the myth that eutrophication is triggered by the release of phosphoric acid from facilities reporting releases in the TRI. A detailed evaluation of EPA's 1990 exposure assessment for phosphoric acid reveals critical flaws in their applied methodology. Significant methodological improvements detailed in this paper fundamentally alter EPA's 1990 exposure assessment and demonstrate that, contrary to EPA's conclusion, these sources of phosphoric acid do not have the potential to trigger eutrophication in surface waters. Therefore, when sound scientific principles are applied in this comparative exposure assessment, EPA's policy maintaining phosphoric acid on the TRI list is inappropriate.