Formulation (ND) Chemical name CAS number Weight percentage (ND) STEPANTEX SP-88-2 Ethanol 64-17-5 10-20% STEPANTEX VT-90 2-Propanol 67-63-0 9-11% STEPANTEX VM-90 2-Propanol 67-63-0 5-15% 2.3 Physical and chemical properties The physical and chemical properties of the notified chemical are shown in the table below. The robust summaries of tests on physical and chemical properties are provided in Appendix C of this report. Summary of physical and chemical properties Property Value Data Source Appearance at 20ºC and 101.3 kPa: Slightly yellowish solid Measured Melting point: > 85°C Measured Boiling point: 260°C (decomposition) Measured Density: 1059 kg/m3 at 20°C Measured Vapour pressure: 6.7 x 10-7 kPa at 25oC Calculated from measured values Water solubility: 2.244 g/L at unbuffered pH 3.86 and 20oC 3.39 mg/L at buffered pH 7.08 and 20oC Measured Hydrolysis as a function of pH: t1/2 >1 year (pH 4), 17.0 days (pH 7) and 11.3 days (pH 9) at 25ºC Measured Partition coefficient (n-octanol/water): log Pow = >6.5 at 20oC Estimated Adsorption/Desorption log Koc = >5 at 20C Calculated Surface tension: 41.8 mN/m at 20ºC Measured Dissociation constant: pKa = 1.14 (methylsulfuric acid) pKa = 12.42 and 13.68 (monoester with C18 ester chain) pKa = 12.52 (diester with C18 ester chain) Calculated Flash point: Not determined The notified chemical is not a liquid. Flammability: Not highly flammable Measured Autoignition temperature: > 402°C Measured
Human, skin sensitisation – human maximisation test (HMT) and diagnostic patch test Analogue 1 Not sensitising Rat, repeat dose oral toxicity – 90 days Analogue 4 NOAEL = 300 mg/kg bw Genotoxicity -bacterial reverse mutation Analogue 5 Non-mutagenic Genotoxicity – in vivo mouse micronucleus test Analogue 1 Not genotoxic The results from the data submitted for the new chemical assessment (NICNAS, 2007) are summarised in the following table and text. The robust study summaries of these data are provided in Appendix A.2. Studies available for the new chemical assessment Endpoint Test substance Result and assessment conclusion Rat, acute oral Analogue 1 LD50 > 2000 mg/kg bw, low toxicity Rat, acute dermal Notified chemical LD50 > 2000 mg/kg bw, low toxicity Rabbit, skin irritation Analogue 1 Slightly irritating Rabbit, eye irritation (undiluted test substance) Analogue 1 Severely irritating Rabbit, eye irritation (undiluted test substance, low volume procedure) Analogue 1 Slightly irritating Rabbit, eye irritation (5% diluted test substance) Analogue 1 Not irritating Guinea pig, skin sensitisation – guinea pig maximisation test (GPMT) Analogue 1 Inconclusive Rat, repeat dose oral toxicity – 28 days Notified chemical NOAEL = 1000 mg/kg bw Genotoxicity -bacterial reverse mutation Analogue 2 Non-mutagenic Genotoxicity – in vitro mammalian chromosome aberration test Notified chemical Non-genotoxic The new chemical assessment (NICNAS, 2007) and the HERA report (2009) noted that the test substances may contain the additive, 2-propanol (CAS no. 67-63-0), which is classified as an eye and respiratory irritant (Safe Work Australia, 2018). Therefore, the toxicity of the analogue could be biased by the toxicity of this impurity. Toxicokinetics, metabolism and distribution No toxicokinetic data were provided for the secondary notification. The original new chemical assessment stated that based on the physical and chemical properties, the absorption of the chemical via the various routes is expected to be as follows:
Test Facility LPT (2005) A2.7 Genotoxicity - bacteria Test Substance Analogue 2 Method OECD TG 471 Bacterial Reverse Mutation Test Plate incorporation procedure Species/Strain S. typhimurium: TA1535, TA1537, TA98, TA100 Metabolic activation system Aroclor 1254-induced rat S9 liver homogenate Concentration range in main test a) With metabolic activation: 8-5000 µg/plate b) Without metabolic activation: 8-5000 µg/plate Vehicle Purified water Remarks - Method A preliminary test was conducted using the TA100 strain of S. typhimurium. The doses chosen for range finding were the following: 10, 32, 100, 320, 1000, 3200 and 10000 g/plate. In order to improve the solubility, the test substance was subjected to ultrasonic treatment and heated to 40 C for 15 minutes. It was not possible to dissolve the test substance completely due to adhesion of the substance on the walls of the vessel. Therefore, the reported concentrations were based on calculated values. Two concentrations of the metabolic activation system (S9) were used: 4% for Test 1 and 10% for Test 2. Results Metabolic activation Test substance concentration (µg/plate) resulting in: Cytotoxicity in preliminary test Cytotoxicity in main test Precipitation Genotoxic effect Absent >32 Test 1 >200 5,000 Negative Test 2 >200 5,000 Negative Present >32 Test 1 >200 5,000 Negative Test 2 >1000 5,000 Negative Conclusion The notified chemical was not mutagenic to bacteria under the conditions of the test. Test Facility International BioResearch (1993) A2.8 Genotoxicity – in vitro Test Substance Notified chemical