Formula: C4H6BrNO4. Molecular Weight: 212.0 D. Antimicrobial effect: Very effective agains bacteria, yeast and fungi. Possible combination: Can be combined other preservatives. Effect: May oxidize thiol groups in essential enzymes systems. Interferences: Interferes with cysteine. Reducing agents lower the preservative effectiveness. Toxicity: Harmless at recommended concentrations; not carcinogenic or mutagenic (Ames-test negative). Recommended working concentration: 0.2 mg/ml, if both the risk of contamination and concentration of protein are low (> 0.2%); 0.4 mg/ml, if both the risk of contamination and concentration os protein and substrate are high. pH optimum: 5.0-7.0. Stability: Not stable at pH < + 5 and temperatures > + 50°C; corrosive. Appearance: White to slightly yellowish crystalline powder. Solubility: Clear, colourless solution in ethanol (c = 10 mg/ml). A405 (c = 10 mg/ml ethanol): ≤ 0.015. Identity (NIR): Corresponds to reference. 5-Bromo-nitro-1.3-dioxane (GC): ≥ 98 area%. Water (K. Fischer): ≤ 0.5%. Impurities (GC): ≤ 2.0 area %. Heavy metals (as Pb): ≤10 ppm. Oxidizing substances: ≤ 1 %. Bromine, free: Negative. Stability: At + 2 to + 8°C within specification range for 18 months.