Cadmium nephropathy:
Source of exposure: Cadmium is a component of metal alloys, in
the manufacture of electrical conductors, electroplating storage batteries,
aircraft industries, as a by-product of iron smelting, as a pigment, in
ceramics, glass, in plastic stabilizer, in photographic developer, rubber or
dental prosthetics. Also, the burning of coal, oil and cigarettes.
Cadmium toxicity: The acute absorption of as little as 10 mg of
dust or fumes will cause severe gastrointestinal symptoms; and 12 hours
later, pulmonary oedema. Chronic low dose exposure will cause
emphysema, anosmia and renal disease. Early renal manifestations are
those of adult Fanconi syndrome, tubular proteinuria and renal tubular
acidosis. Urinary calculi are detected in 40 per cent of cases. In late phases
chronic renal failure appears.
Treatment: Ca Na 2 EDTA is of little value after cadmium has
fixed in tissues. Vitamin D and calcium may be of help for bone disease,
but may aggravate renal disease (by more stone formation).
Mercury nephrotoxicity:
Mercury toxicity depends on its chemical form and route of
administration. Elemental mercury is harmless when ingested but when its
vapour is inhaled will be very toxic. Environmentally, mercury is either
organic or inorganic salt. Toxicity is usually caused by methyl, ethyl, or
phenoxyethyl organic salts and the chloride salt.