The trace element content of various intravenous solutions was investigated, using atomic absorption and neutron activation analysis methods. The variable content of zinc, calcium, and magnesium led us to seek a source of contamination. Quantities of zinc ranging from 10.75μg to 132μg were leached from the rubber stoppers when placed in 0.1N nitric acid for a period of 96 hours. Calcium and magnesium were also leached from the stoppers, but in lesser amounts.
(Arch Intern Med 136:782-784, 1976)