Effect of single gallium arsenide exposure on some biochemical variables in porphyrin metabolism in rats.

Gallium arsenide (GaAs) inhibited, dose dependently, delta-aminolevulinic acid dehydratase (ALAD) activity in blood (as observed on days 1, 7 and 15), liver and brain (on day 15) after a single oral treatment. Levels of blood zinc protoporphyrin (ZPP) and urinary delta-aminolevulinic acid (ALA) excretion were elevated on day 7 and day 15 following exposure to 2000 mg kg-1 GaAs. A dose-dependent increase in blood As contents was observed while blood Ga was detectable only at higher doses.