Used as a reference standard in environmental testing laboratories to calibrate instruments and validate analytical methods for detecting bismuth in water samples. Ensures accuracy and reliability in monitoring bismuth levels, which is important for assessing water safety and compliance with environmental regulations. Commonly used in conjunction with techniques like atomic absorption spectroscopy (AAS) or inductively coupled plasma mass spectrometry (ICP-MS). Helps maintain quality control in routine water analysis and supports research on trace metal contamination.