Radiation from Japan has been detected in drinking water in 13 more American cities, and cesium-137 has been found in American milk -- in Montpelier, Vermont -- for the first time since the Japan nuclear disaster began, according to data released by the Environmental Protection Agency [on April 8]. Milk samples from Phoenix and Los Angeles contained iodine-131 at levels roughly equal to the maximum contaminant level permitted by EPA, the data shows. The cesium-137 found in milk in Vermont is the first cesium detected in milk since the Fukushima-Daichi nuclear accident occurred last month. The sample contained 1.9 picoCuries per liter of cesium-137, which falls under the [EPA's] 3.0 standard. Airborne contamination continues to cross the western states, the new data shows, and Boise has seen the highest concentrations of radioactive isotopes in rain so far. A rainwater sample collected in Boise on March 27 contained 390 picocures per liter of iodine-131, plus 41 of cesium-134 and 36 of cesium-137. EPA released this result for the first time yesterday. Typically several days pass between sample collection and data release because of the time required to collect, transport and analyze the samples. In most of the data released Friday the levels of contaminants detected are far below the standards observed by EPA and other U.S. agencies.