Toxicity identification of effluent from a semiconductor lead frame manufacturing factory

The acute toxicity of lead frame effluent to Daphnia magna was found to be 22.62 TU, which far exceeded the toxicity discharge limit in Korea (<1 TU). TIE phases I and II result suggest that the mixture of Ag, Cu and CN were likely responsible for the observed toxicity, and this was confirmed by mass balance approach (TIE phase III). In addition, the Visual MINTEQ simulation suggested the presence of [Ag(CN)2]− and [Cu(CN)3]2− complexes in the effluent. Therefore, TIE procedures with chemical speciation modeling were effective for identifying the cause of acute toxicity in industrial effluents.