Effect of chronic and acute lead treatment in the slug Arion ater on calcium and delta-aminolaevulinic acid dehydratase activity.

Accumulation of lead in the tissues was greater after acute exposure. Most of the metal was deposited in the intestine and least in foot. After chronic exposure to lead the calcium content of the intestine decreased. After chronic and acute exposure to lead the calcium content of the digestive gland and foot was lower than control values. Lead in the digestive gland granules was higher after acute lead treatment. Less than 45% of the lead was associated with the granules. These results are discussed in view of the difference in metabolism and chemical nature of the organs investigated. ALAD activity was located in the digestive gland and it was reduced after acute treatment with lead.