True about plumbism is:

Lead poisoning (plumbism) occurs chiefly as an occupational hazard today, but occasionally occurs because of some other accidental exposure of either an acute or chronic nature. The formation of a 'lead line' similar to the 'bismuth line' occurs in lead poisoning. This grey or bluish black line of sulphide pigmentation occurs in the gingiva, but is somewhat more diffuse than that of bismuth. Lead intoxication is manifested by serious gastrointestinal disturbances which include nausea, vomiting, colic, and constipation. A peripheral neuritis also develops which may produce the characteristic wrist-drop or foot-drop. Encephalitis may also occur. Blood changes are those of hypochromic anaemia with basophilic stippling of the red blood cells. Skeletal changes due to deposition of lead in growing bone occur in children and are demonstrable on the radiograph. Reference: Shafer’s Textbook of ORAL PATHOLOGY Eighth Edition page no 691,692