Effects of humic acid and water hardness on acute cadmium toxicity by using Simocephalus exspinosus as a bioindicater

الملخص EN

This paper was based on study the effect of humic acid and water hardness on acute cadmium toxicity by using Simocephalus exspinosus as a bio indicator.

The toxicities were expressed by the median lethal concentration (LC50), and the LC50value for (48-h) of cadmium was 2.5 mg / L.

Three concentrations of humic acid were used (50, 75 and 100) mg \ l, the acute cadmium toxicity significantly decreased by increasing humic acid concentration.

An increased in water hardness (75 and 100) mg \ l CaCO3 considered as (moderate hardness and hard) respectively also significantly decreased acute toxicity of cadmium.