when it is to be "taken out of a solution", chemists usually would use
"removable".

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Note added at 16 mins (2010-02-02 15:02:04 GMT)
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http://scialert.net/fulltext/?doi=rjes.2009.292.298

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Note added at 17 mins (2010-02-02 15:03:47 GMT)
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Urban activities may significantly contribute to elevated heavy metal loads in atmospheric deposits and consequently in the edible portion of the vegetables. Thus the present study was conducted with the objectives to investigate the accumulation of heavy metals (Cu, Zn, Pb) on the (Talinum triangulare, Celosia argentea, Amaranthus viridis, Cucurbita maxima and Corchorus olitorius) leaf surfaces through the concurrent analysis of unwashed and washed leaves from urban and remote areas. Water-washing by shaking mechanically removes much of the particulate found on the leaf surfaces, allowing the fractions of particle-bound heavy metals to be estimated. This study therefore, aimed to distinguish the ** water-removable fraction of heavy metals ** and the fraction present in leaves, potentially supplying useful information on the pollutant fraction damaging to leaf physiological processes.