A research team in Ehime University, Japan conducted a comprehensive profiling of chlorinated and brominated compounds bioaccumulated in the liver of various wild bird species from Osaka, Japan in order to find potentially harmful but "hidden" contaminants. The team found a specific accumulation of several groups of typically unmonitored halogenated contaminants in raptors, including those so far never been reported in wild animals. The findings were published in Environmental Science & Technology on June 8, 2021.