In general, the intact enamel cup is not harmful to the human body, you can rest assured that it can be used. Enamel cup is enameled at high temperatures, does not contain toxic substances, you can rest assured that the use of enamel cups contain metal substances, relatively stable, but under the influence of acidity may dissolve metal substances, so try not to use enamel cups to hold cola, orange juice and other acidic beverages, so as not to dissolve the metal substances, harmful to the human body. Enamel cup surface is relatively fragile, easy to break after bumping, will release harmful substances, so to safely use enamel cups, try to avoid bumping the situation. Enamel cup will appear to drop porcelain, exposed iron tire will rust when encountering water, this situation will try not to use, so as not to metal substances into the human body, affecting health.