The International Atomic Energy Agency says a plutonium leak at its laboratory earlier this month did not contaminate the environment, AP reported. The agency says independent analysis of soil, plant and water samples show that no radioactivity was released into the surrounding area during the Aug. 3 incident. It says that a tiny amount of plutonium contained in an acid solution spilled from five small glass vials when one of them burst after a buildup of pressure inside it. Virtually all the contamination was confined within a steel-walled safe where the vials were stored. The laboratory is located about 35 kilometers (22 miles) southeast of Vienna. The IAEA said Friday that an investigation into the cause of the incident is still under way.