perfluorononanoic acid
... that perfluorononanoic acid, an environmental contaminant, has been detected in polar bears in concentrations over 400 parts per billion?
... that <b id="mwAno"><a href="./Perfluorononanoic_acid" id="mwAns" rel="mw:WikiLink" title="Perfluorononanoic acid">perfluorononanoic acid</a></b>, an <a class="mw-redirect" href="./Environmental_contaminant" id="mwAnw" rel="mw:WikiLink" title="Environmental contaminant">environmental contaminant</a>, has been detected in <a href="./Polar_bear" id="mwAn0" rel="mw:WikiLink" title="Polar bear">polar bears</a> in concentrations over 400 parts per billion?