Effectiveness of amendments on the spread and phytotoxicity of contaminants in metal-arsenic polluted soil

► The effectiveness of soil amendments was studied in lixiviates and in pore water. ► Heavy metals and arsenic showed different partitioning. ► The amendment which was effective against arsenic was not effective against metals. ► The amendment that fixed metals increased the arsenic concentration in lixiviates. ► Using amendments in combination did not improve the effectiveness.