January 29, 2019 Document Control Officer (DCO) Office of Pollution Prevention and Toxics (OPPT) US Environmental Protection Agency (7401M) 1200 Pennsylvania Avenue, N.W. Washington, DC 20460 SUBJECT: Additional Information for P-18-0257 Everris NA Inc. wishes to submit to EPA responses to the agency’s review of the PMN substance under P- 18-0257. We respectfully request the agency to further consider these responses which are provided with additional information to support P-18-0257. Hi-Peak is a double salt crystal with the empirical formula K3H3(PO4)2, composed of monopotassium phosphate (MKP - KH2PO4) and dipotassium phosphate (DKP - K2HPO4) salts. During its intended use, once dissolved in water, Hi-Peak dissociates behaving as a mixture of two known, TSCA listed compounds: monopotassium phosphate (MKP - KH2PO4) (CAS No. 7778-77-0) and dipotassium phosphate (DKP - K2HPO4) (CAS No. 7758-11-4). These two compounds, Monopotassium Phosphate (MKP) and Dipotassium Phosphate (DKP), are known as common fertilizers that are highly soluble in water and are applied to plants through watering after dissolving in water (terms P-25 and P-26 of AAPFCO, official edition, 2002). The intended use of the PMN substance as an element in Hi-Peak will be applied as an inorganic fertilizer through watering as well. In addition to its use as a fertilizer, monopotassium phosphate (MKP - KH2PO4) and dipotassium phosphate (DKP - K2HPO4) salts are used as food additives. We refer to listings found in the FCC (Food Chemicals Codex and (EU) No 231/2012: E 340 (i) monopotassium phosphate (MKP); E 340 (ii) dipotassiumphosphate (DKP). Both also have known cosmetic uses (EU Inventory of Cosmetic Ingredients and Fragrances Decision 96/335/EC establishing INCI list and Cosmetic Ingredients/Fragrances Inventory Version 2, last update 8 May 2015). And further, both substances are recognized as GRAS in accordance with 21 C.F.R. Part 169.110 and (21 C.F.R. Part 182.6285, and 21 C.F.R. Part 133.169 respectively. Both MKP and DKP are listed under OSPAR PLONAR list of substances/preparations used and discharged offshore which are considered to pose little or no risk to the environment (2018). Both compounds identified by their respective CAS registry numbers do not meet the criteria for classification according to the GHS (Global Harmonized System) – SDSs (See Appendix 1). As such, and in view of the above, it can be assumed that both compounds from Hi-Peak do not present unreasonable risk to human health or the environment. This should also be the case for the aqueous mixture of Hi-Peak. ICL 11636 Huntington Road Gallipolis Ferry, WV 25515 Tel. 304-675-1150 ext. 483 Fax. 304-675-4657 E-mail: [email protected] ECOTOXICITY EPA stated regarding the submitted Algae inhibition study (project number: 3113/0004): "This algal test is not acceptable as it does not address the concern for eutrophication potential of the phosphoric acid". Further to this conclusion, experimental chronic ecotoxicity values were not available for assessment. Therefore, EPA has estimated the environmental hazard of this new chemical substance using both a hazard data on the new chemical substance, as well as on analogous chemicals. "Based on these estimated hazard values, EPA concludes that this chemical substance has a high environmental hazard." Comments by Everris NA Inc.: 1. General comments regarding the composition of Hi-Peak that includes the PMN substance P-18-0257: Hi-Peak is a double salt crystal with the empirical formula K3H3(PO4)2 as indicated by the XRD and elemental analysis provided. The Hi-Peak double salt crystal is composed of monopotassium phosphate (MKP - KH2PO4) and dipotassium phosphate (DKP - K2HPO4) salts. Monopotassium phosphate (MKP) and dipotassium phosphate (DKP) are two known fertilizers, appearing in the TSCA list of active chemicals. Both fertilizers are highly soluble in water and are applied to plants through watering after dissolving in water. Hi-Peak (which includes the PMN substance) will be applied as a fertilizer to plants through watering as well. The following equations represent dissolution in water of MKP and DKP (1:1) and Hi-Peak: + 2- - K2HPO4 + KH2PO4 3K (aq) + HPO4 (aq) + H2PO4 (aq) Hi-Peak solubility in water equation + 2- - K3H3(PO4)2 3K (aq) + HPO4 (aq) + H2PO4 (aq) As indicated from the equations above, both equations present the same ionic stoichiometric ratio in water. The ionic composition of MKP and DKP (1:1 mixture) is identical to the ionic composition of Hi-Peak after dissolving in water. Once applied through watering to the environment, Hi-Peak behaves exactly as a mixture of MKP and DKP (1:1 mixture). 2. The alga toxicity study was conducted in accordance with GLP standards and OECD test guideline No. 201 (2006) and OPPTS 850.5400 guideline (Algal Toxicity, Tiers I and II) in a well-reputable and experienced laboratory. The OECD 201 guideline is designed to test toxicity of the test substance to the algae organism. Eutrophication potential is not a parameter that is in the scope of the OECD 201 guideline or the OPPTS 850.5400 guideline (Algal Toxicity, Tiers I and II). The results of the study show clearly that there is no inhibition of the alga's growth following exposure to the test substance. ICL 11636 Huntington Road Gallipolis Ferry, WV 25515 Tel. 304-675-1150 ext. 483 Fax. 304-675-4657 E-mail: [email protected] We believe that valid experimental results on an actual substance should always take precedence over the use of a model, on an analog substance. Therefore, since the algal study met all the requirements of the guidelines, it is justified to use the experimental data which were generated on the PMN substance, rather than using estimated values from a computational model of another molecule (analog). 3. In the conclusions of the EcoTox studies, EPA is using EC50 and ChV calculated values to estimate toxicity of the analog to algae. These values are used for read-across instead of the experimental algal data. As was argued in the previous comment, we believe that the algae study is valid and the EC50 and NOEC of the actual study should be used. 4. It is understood by Everris NA Inc. that the presented analog values are derived from EpiSuite Software. According to EpiSuite Help guide (Overview & intro 1.2. Limitations): "It is important to stress that EPI Suite™ is a screening-level predictive tool and cannot be used for all chemical substances. ………….. The intended application domain of EPI Suite is organic chemicals, and inorganic as well as organometallic chemicals generally can be considered outside the domain." (see attachment in Appendix 1). Therefore, to our understanding the assumptions used to justify the use of the EpiSuite model on this inorganic substance are inaccurate and not suitable. 5. According to EPA the algal test is not acceptable as it does not address the concern for eutrophication potential of the phosphoric acid. Eutrophication potential is not a parameter that is assessed by the OECD 201 guideline or by the OPPTS 850.5400 guideline (Algal Toxicity, Tiers I and II). Thus, we find this reason for rejecting the alga study unjustified. Nevertheless, we calculated the Eutrophication potential for MKP, DKP and Hi-Peak using the model: http://www.cheminfo.org/Chemistry/Eutrophication_potential/index.html The calculation shows identical values for all three substances as presented in the following table. Thus, we strongly believe that no environmental hazard is expected for Hi-Peak based on similarity to MKP and DKP. Eutrophication potential of the three substances Substance Eutrophication potential MKP 0.9686 DKP 0.9769 Hi-Peak 0.9727 ICL 11636 Huntington Road Gallipolis Ferry, WV 25515 Tel. 304-675-1150 ext. 483 Fax. 304-675-4657 E-mail: [email protected] The eutrophication potential model outcome: MKP Calculation: DKP Calculation: HiPeak Calculation: Summary of Ecotoxicity comments: A. The Algal study submitted is valid in accordance with OECD 201 and OPPTS 850.5400 guideline (Algal Toxicity, Tiers I and II). Therefore, should be accepted. B. The EPI Suite™ is not suitable usually for inorganic substances and for this substance. It also does not predict eutrophication potential. Therefore, it should not be used instead of a valid experimental study due to lack of eutrophication. C. Eutrophication potential has been calculated in this document and should be considered in EPA's evaluation of the PMN substance in Hi-Peak. D. This substance does not pose an unreasonable risk to the environment, as it is similar to known and used fertilizers, which are also included in the OSPAR PLONOR list of substances/preparations used or discharged offshore which are considered to pose little or no risk to the environment (2018). Human Health EPA concluded that there is low/ moderate concern for human health hazard for the chemical substance. Based on the hazard determination and available quantitative and qualitative risk information, EPA concluded the following risks for the PMN substance: • Absorption is expected to be nil through the skin and good through the lungs and GI tract (Physical Chemistry and data on phosphate salts). • Concern for kidney toxicity and lungs toxicity based on hazards identified in 2011 PPRTV document for inorganic phosphates. • Concern for eye irritation based on submitted data. Comments by Comments by Everris NA Inc.: 1. General comment regarding choice of the analog: Phosphoric acid is used by EPA as the analog for oral exposures. We believe that the use of phosphoric acid as an analog to Hi-Peak is inaccurate based on the following argument: Phosphoric acid has three acidic protons (H3PO4). The first proton dissociate from phosphoric acid is highly acidic with pKa of 1.8 (see pKa table in appendix 1).