Toxicity identification and evaluation of a refinery wastewater from Brazil (Phase I)

Petroleum refineries generate a large amount of effluents, which if released without appropriate treatment can cause chronic effects to organisms. Most studies show that many contaminants can be responsible for the toxicity, among them ammonia, sulfide, cyanide, phenol and hydrocarbons. The present study evaluated the cause of the chronic toxicity of a refinery wastewater from Brazil using the organism Ceriodaphnia dubia in short-term test. The results suggest that metals such as barium, manganese and strontium can be contributing for the toxicity of the wastewater. Besides this, conductivity could be contributing to the toxicity too, since the level is high for the test organism evaluated.