RESUMO
A plant bioassay using hydroponically grown Ipomoea aquatica (water spinach) was applied to assess the phytotoxicity of untreated and treated wastewaters from a municipal solid waste incineration bottom ash recycling facility. The 50%-diluted, untreated wastewater exhibited acute toxicity (plants died within 24 hours). Highly diluted doses (3 and 6%) of both wastewater types displayed no significant differences when compared with the control. Treating the wastewater through sequential physical filtration and chemical precipitation processes decreased not only the dissolved solids content but also the pH and salt content. In addition, significant accumulations of Sr, Cr, and Sn were observed in the hydroponically grown I. aquatica plant tissues; in particular, the bioaccumulation of Sr in the leaves and roots was unexpectedly high.
