Gout, glaucoma, paleness, weakness and drooping of the wrists and ankles, wasting of the shoulder girdle muscles, low sex hormones (with the corresponding pituitary hormones elevated, unlike for mercury where both pituitary factors and hormones are relatively low)., fear of being murdered. The victim will feel worse at night, and better during exercise.
The victims will also have a lot of gastrointestinal pain (colic) and gas.
There are many laboratory test abnormalities that are distinctive for lead poisoning that can be used to see how much of a problem lead is versus mercury for a particular person. Results in the high end of the normal range are significant for a person who also has some mercury in them because lead and mercury are synergistic in their effects.
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There are a variety of laboratory tests for the metabolic effects of lead. In addition, certain changes observed in a blood count are typical of lead and not of the other toxins. Lead levels in hair, urine and blood are representative of body burden. Free erythrocyte protoporphyrin zinc protoporphyrin and urinary aminolevulinic acid are specific tests for lead intoxication.
Coexistence of gout is diagnostic for lead.
Wrist or ankle drop is diagnostic for lead.
Chronic mercury intoxication can be difficult to diagnose because large quantities of mercury can be sequestered in the internal organs yet most of the mercury in the extra cullular compartment may have been excreted long ago. Thus a "low" mercury excretion may mean someone is fine, or it may mean someone was poisoned to the gills so long ago it is no longer apparent by measuring excretion. Unlike, mercury, lead has a long excretion half life., So lead excretion will be indefinitely elevated if lead poisoning has occurred and no chelation treatment has been given in the meantime.
While some controversy surrounds the hair element test, authoritative sources like Tietz accept it as a useful screening test for heavy metal intoxications such as lead and arsenic.