2. The glass does not contain organic chemicals in the firing process, and the glass will not release related toxins because the water temperature is too high, which is very safe. The glass surface is smooth and easy to clean, especially bacteria and dirt are not easy to breed on the glass wall, so drinking water from the glass is very healthy and safe. Ceramic cups and glasses have similar characteristics, but many ceramic cups are easy to add harmful glaze during firing, which easily leads to excessive lead content. Therefore, in the selection process, glass cups are the best, followed by ceramic cups.