RISK ASSESSMENT REPORT ZINC PHOSPHATE CAS-No.: 7779-90-0 EINECS-No.: 231-944-3 GENERAL NOTE This document contains: - part I Environment (pages 44) - part II Human Health (pages 124) R077_0805_env RISK ASSESSMENT ZINC PHOSPHATE CAS-No.: 7779-90-0 EINECS-No.: 231-944-3 Final report, May 2008 PART 1 Environment Rapporteur for the risk evaluation of zinc phosphate is the Ministry of Housing, Spatial Planning and the Environment (VROM) in consultation with the Ministry of Social Affairs and Employment (SZW) and the Ministry of Public Health, Welfare and Sport (VWS). Responsible for the risk evaluation and subsequently for the contents of this report is the rapporteur. The scientific work on this report has been prepared by the Netherlands Organization for Applied Scientific Research (TNO) and the National Institute of Public Health and Environment (RIVM), by order of the rapporteur. Contact point: Bureau Reach P.O. Box 1 3720 BA Bilthoven The Netherlands R077_0805_env PREFACE For zinc metal (CAS No. 7440-66-6), zinc distearate (CAS No. 557-05-1 / 91051-01-3), zinc oxide (CAS No.1314-13-2), zinc chloride (CAS No.7646-85-7), zinc sulphate (CAS No.7733- 02-0) and trizinc bis(orthophosphate) (CAS No.7779-90-0) risk assessments were carried out within the framework of EU Existing Chemicals Regulation 793/93. For each compound a separate report has been prepared. It should be noted, however, that the risk assessment on zinc metal contains specific sections (as well in the exposure part as in the effect part) that are relevant for the other zinc compounds as well. For these aspects, the reader is referred to the risk assessment report on zinc. 2 CAS No.7779-90-0 R077_0805_env CONTENTS 0 OVERALL CONCLUSIONS/RESULTS OF THE RISK ASSESSMENT 6 1 GENERAL SUBSTANCE INFORMATION 9 1.1 Identification of the substance 9 1.2 Environmental classification and labelling of zinc phosphate 10 1.2.1 Introduction 10 1.2.2 Test results water solubility and aquatic toxicity 10 1.2.3 Conclusion 11 2 GENERAL INFORMATION ON EXPOSURE 12 2.1 Production 12 2.2 Use pattern 12 3 ENVIRONMENT 14 3.1 General introduction 14 3.2 Environmental exposure 15 3.2.1 Exposure scenarios 16 3.2.1.1 General 16 3.2.1.2 Local exposure assessment 18 3.2.1.2.1 General 18 3.2.1.2.2 Production of zinc phosphate 18 3.2.1.2.3 Formulation and processing of zinc phosphate in paints 26 3.2.1.2.4 Measured local data in the environment 29 3.2.1.2.5 Summary of results for the local exposure assessment 29 3.3 Effects assessment 30 3.3.1 Aquatic and terrestrial compartment 30 3.3.2 Atmosphere 31 3.3.3 Secondary poisoning 31 3.4 Risk characterisation 32 3.4.1 General 32 3.4.2 Local risk characterisation 36 3.4.2.1 Aquatic compartment 36 3.4.2.1.1 STP effluent 36 3.4.2.1.2 Surface water (incl. sediment) 36 3.4.2.2 Terrestrial compartment 37 3.4.2.3 Atmospheric compartment 38 3.4.2.4 Secondary poisoning 38 3.4.3 Regional risk characterisation 40 APPENDIX 3.4 BIOAVAILABILITY CORRECTIONS 42 3 CAS No.7779-90-0 R077_0805_env 4 REFERENCES 44 4 CAS No.7779-90-0 R077_0805_env 5 CAS No.7779-90-0 R077_0805_env 0 OVERALL CONCLUSIONS/RESULTS OF THE RISK ASSESSMENT CAS No. 7779-90-0 EINECS No. 231-944-3 IUPAC Name Trizinc bis(ortho)phosphate ( ) i) There is need for further information and/or testing (X) ii) There is at present no need for further information and/or testing and for risk reduction measures beyond those which are being applied already (X) iii) There is a need for limiting the risks; risk reduction measures which are already being applied shall be taken into account (X) iii*) A conclusion applied to local scenarios in which the local scenario merits conclusion (ii) but where (possibly) due to high regional background concentrations a local risk cannot be excluded. LOCAL Conclusion (ii) is drawn for all local scenarios, including secondary poisoning, except those listed below. Conclusion iii) or iii*) is drawn for the specified scenarios, because: STP • the PECSTP exceeds the PNECadd for microorganisms in three processing scenarios listed in Table 3.4.10 (conclusion iii). Surface water • the Clocaladd in water exceeds the PNECadd for surface water in a number of processing scenarios listed in Table 3.4.10 (conclusion iii). Sediment • the Clocaladd / PNECadd ratio is larger than 1 for a number of processing scenarios listed in Table 3.4.10 (conclusion iii). For the production sites and remaining processing scenarios listed in Table 3.4.10 the Clocaladd / PNECadd ratio is <1, but a potential risk at local scale cannot be excluded due to the possible existence of high regional background concentrations (conclusion iii*). Soil • one processing scenario listed in Table 3.4.10 resulted in a PECadd / PNECadd ratio >1 (conclusion iii). 6 CAS No.7779-90-0 R077_0805_env REGIONAL The regional risk characterisation is discussed in the RAR on Zinc Metal. 7 CAS No.7779-90-0 R077_0805_env 8 CAS No.7779-90-0 R077_0805_env 1 GENERAL SUBSTANCE INFORMATION 1.1 IDENTIFICATION OF THE SUBSTANCE CAS-No.: 7779-90-0 EINECS-No.: 231-944-3 IUPAC name: trizinc bis(orthophosphate) Synonyms: zinc phosphate; zinc orthophosphate; phosphoric acid-zinc salt Molecular formula: Zn3(PO4)2 · 2-4H2O Structural formula: Zn3(PO4)2 · 2-4H2O Molecular weight: 458.14 Purity/impurities, additives Purity: no data Impurity: <0-4.5% zinc oxide, typical <100 ppm lead, <100 ppm cadmium Additives: none Physico-chemical properties In table 1A the physico-chemical properties are summarized. Table 1A Physico-chemical properties of zinc phosphate Property Result Comment Physical state solid, powder Melting point 900 ºC * Boiling point not applicable **** Relative density 3.3 at 20 ºC ** Vapour pressure not applicable **** Surface tension not applicable **** Water solubility very slightly soluble - insoluble * Solubility in other solvents soluble in acids and NH4OH; insoluble in alcohol *** Partition coefficient no data **** n-octanol/water(log value) 9 CAS No.7779-90-0 R077_0805_env Property Result Comment Flash point not flammable **** Flammability not flammable **** Autoflammability temperature not applicable **** Explosive properties not explosive **** Oxidizing properties not oxidizing **** * More than one apparently independent source. No methods are specified. ** Several values found in literature. The value presented is considered as most appropriate. *** One source **** Conclusion based on theoretical, and/or structural considerations. These data are mainly derived from CRC Handbook of Chemistry and Physics (1995), Römpp Chemie Lexikon (1995), and company MSDS's. For an extended description see HEDSET. Conclusion: Data on boiling point and partition coefficient were not provided. In view of the nature of the substance determination of these parameters is considered to be irrelevant. Vapour pressure and surface tension are reported to be not applicable. This is correct based on theoretical considerations. Information on flammability, explosive properties and oxidizing properties is not available. However, on theoretical considerations the compound is concluded to be not flammable, not explosive and not oxidizing. All other required physico-chemical data were submitted. None of these data is based on test results, substantiated with reports. However, the data are considered as sufficiently reliable to fulfil the Annex VIIA requirements. 1.2 ENVIRONMENTAL CLASSIFICATION AND LABELLING OF ZINC PHOSPHATE 1.2.1 Introduction For a general introduction on the classification and labelling of metals, the reader is referred to sections 1.2.1 and 1.2.2 of the risk assessment report on zinc metal. 1.2.2 Test results water solubility and aquatic toxicity The results of Heubach (1996) indicate a water solubility of ±10, ±100 and >1000 mg dissolved Zn/l at pH 8, 7 and 6, respectively. These summarised results of the Heubach-study (1996) will be used for classification. 10 CAS No.7779-90-0 R077_0805_env There are no short-term toxicity data available for zinc phosphate. The water solubility of zinc phosphate will be related to the L(E)C50-values of zinc chloride or zinc sulphate for classification. This classification approach is described in the testing strategy document (ECBI/61/95-Add 51-Rev. 4) and summarised in the diagram 1.1/2 in section 1.2.2 of the risk assessment report on zinc metal (RAR Zinc metal). The L(E)C50 values of the soluble zinc salts are presented in Table 1.2 (section 1.3.2.2) of the zinc metal report. The selected values for Daphnia magna, Oncorhynchus mykiss and Selenastrum capricornutum are a 48-hour EC50 of 0.07 mg/l, a 96-hour LC50 of 0.14 mg/l and a 72-hour EC50 of 0.14 mg/l, respectively. 1.2.3 Conclusion The water solubility of zinc phosphate exceeds the lowest L(E)C50 values for Daphnia magna, algae and fish. Zinc phosphate has thus been classified with N R50-R53. This classification for zinc phosphate has been included in Annex I of the EU-Directive 67/548/EC, see below. Classification and labelling (human health, environment and physico-chemical) Annex 1 of Directive 67/548/EEC contains a list of harmonised classifications and labellings for substances or groups of substances, which are legally binding within the EU. For zinc phosphate the current Annex 1 classification and labelling (29th ATP, 2004) is as follows: Classification N; R50-53 Labelling N; R50/53 S60-61 11 CAS No.7779-90-0 R077_0805_env 2 GENERAL INFORMATION ON EXPOSURE 2.1 PRODUCTION The zinc phosphate production sites in the European Union with a volume of more than 1000 t/y are presented in Table 2.1.1.