Crystal glass is usually made of high-purity glass material, with elegant appearance and good transparency. From a safety point of view, crystal cups are usually safe drinking water. High-quality crystal glass will not release harmful substances or chemicals into water, so it will not cause direct harm to human health. If low-quality or inferior crystal glass is used, there will be some potential risks. These low-quality cups contain lead or other harmful substances, which will be released when they come into contact with water, causing potential harm to health. In order to ensure safety, it is recommended to choose high-quality crystal cups and avoid using cups of unknown origin or suspicious quality.