1.   But it is the religious or magical use of metallic mercury that worries researchers most, because it tends to go unreported.

2.   Last July, the EPA and the Agency for Toxic Substances and Disease Registry issued a warning about the danger of metallic mercury.

3.   Medical research has shown that even at low levels, exposure to metallic mercury can cause damage even before symptoms arise.

4.   Metallic mercury, the kind the teen-agers found and played with here, enters the blood when vapors given off by the heavy liquid are inhaled.

5.   Part of the problem, he said, is that people do not understand how dangerous metallic mercury can be.

6.   There is no routine mercury test for young children, like the mandatory lead test, because most people never come close to metallic mercury.

7.   An offering vessel near the tomb contained bits of jade, animal bone and bits of shell burned together with cinnabar, leaving a metallic mercury residue.