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Effect of Penicillamine in Promoting Lead Excretion
Canadian Medical Association Journal
|March 24, 2010
Summary
Occupational lead exposure in 14 subjects elevated porphyrin levels, despite normal lead excretion. Penicillamine administration revealed increased lead excretion and decreased porphyrin levels, indicating subclinical lead toxicity.
Area of Science:
- Environmental Health
- Toxicology
- Biochemistry
Background:
- Chronic occupational lead exposure can lead to subclinical toxicity.
- Elevated porphyrin levels in blood and urine are indicators of lead exposure.
- Assessing lead burden in asymptomatic individuals requires sensitive diagnostic methods.
Purpose of the Study:
- To investigate porphyrin and lead levels in occupationally exposed individuals.
- To evaluate the effect of a provocative dose of penicillamine on lead and porphyrin excretion.
- To identify subclinical lead intoxication in workers with no obvious symptoms.
Main Methods:
- Spectrochemical analysis of urine and blood samples.
- Measurement of porphyrin and lead content before and after penicillamine administration.
- Comparison of results with normal reference values.
Main Results:
- Exposed subjects showed higher average total urinary porphyrin (0.506 mg/L) and erythrocyte porphyrin (76.8 µg%) than normal values.
- Baseline lead excretion was lower in exposed subjects (<0.013 mg/L) compared to normal (0.031 mg/L).
- Penicillamine administration significantly increased lead excretion (0.367 mg/L) and decreased porphyrin levels.
Conclusions:
- Penicillamine is effective in mobilizing lead, revealing subclinical lead exposure.
- Elevated porphyrins and altered lead excretion patterns indicate latent toxicity in occupationally exposed individuals.
- This study highlights the importance of provocative testing for early detection of lead poisoning.
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