This study investigated the possibility of phosphogypsum (PG) recycle as an embankment material by eco-toxicity experiments for S. capricornutum, T. suecica and D. magna. The eco-toxicity experiment was studied according to column leachates from PG mixing ratio, and a specific growth rate of S. capricornutum was usually higher than that of T. suecica. For D. magna, 0.3 of toxicity unit was obtained, which indicated the below of toxicity value of 1 at PG50 condition during a 48-hr test. A minor effect of column leachate samples on three organisms was observed. This study suggested that PG was satisfied with the criteria of waste recycle and could be reused at PG30 condition.

The objective of this study was to determine the feasibility of recycled phosphogypsum (PG) as an embankment material with soil by performing batch and column ecotoxicity experiments. A. salina, D. magna, O. latipes and S. capricornutum were selected for the experiment. The effective concentration (EC 50 ) of D. magna was the lowest value, 1.29 mg/L. The survival rates of A. salina, D. magna and O. latipes were more than 90% in the presence of PG leachate in the column test. The toxicity unit (TU) for the organisms was less than 1, indicating that no significant ecotoxicity effect was found. These findings suggested that PG could be recycled for use as an embankment and landfill material with soil.