Its chemical properties as one of the alkali metals make it one of the most problematic of the short-to-medium-lifetime fission products because it easily moves and spreads in nature due to the high water solubility of its salts, and is taken up by the body, which mistakes it for its essential congeners sodium and potassium.
ɪts kˈɛmɪkəl pɹˈɑːpɚɾiz æz wˈʌn ʌvðɪ ˈælkəlˌaɪ mˈɛɾəlz mˌeɪk ɪt wˈʌn ʌvðə mˈoʊst pɹˌɑːbəlmˈæɾɪk ʌvðə ʃˈɔːɹttəmˈiːdiəmlˈaɪftaɪm fˈɪʃən pɹˈɑːdʌkts bɪkˈʌz ɪɾ ˈiːzili mˈuːvz ænd spɹˈɛdz ɪn nˈeɪtʃɚ dˈuː tə ðə hˈaɪ wˈɔːɾɚ sˌɑːljuːbˈɪlᵻɾi ʌv ɪts sˈɔlts, ænd ɪz tˈeɪkən ˌʌp baɪ ðə bˈɑːdi, wˌɪtʃ mɪstˈeɪks ɪt fɔːɹ ɪts ᵻsˈɛnʃəl kəndʒˈɛnɚz sˈoʊdiəm ænd pətˈæsiəm.