|
|
|
| The Acute Toxicity of Cr6+/Cd2+to Snail Thais clavigera |
| XIE Jia-yan,ZHU Ai-yi |
|
|
|
|
Abstract The acute toxicity of Cr6+ /Cd2+ to snail Thais clavigera was studied in 24 ,48 ,72 and 96 h at varied temperature and densities ,and the accumulation of Cr6+ /Cd2+ was analyzed in the viscera and feet of the snail by atomic absorption spectroscopy .The results showed that Cr6+ was found low‐toxic and Cd2+ mid‐toxic to the snail ,Cd2+ being more toxic than Cr6+ ,with safe concentration of 7 .94 mg/L in Cr6+ and 0 .74 mg/L in Cd2+ ,10 times higher toxicity in Cd2+ than in Cr6+and much more higher than the fishery water quality standard (Cr6+ ≤0 .1 mg/L ;Cd2+ ≤ 0 .005 mg/L) ,and as high 79 times for Cr6+ as the standard and 148 times for Cd2+ as the standard .The higher mortality and more rapid death were observed at higher temperature in the snail by Cr6+ and Cd2+ in an interval within certain range . Absorption of Cr6+ and Cd2+ by the snail was found to be increased with rising temperature within given ranges .Temperature led to higher accumulation of Cr6+ than the accumulation of Cd2+ .There was more accumulation of heavy metals in the viscera than in foot muscle .The accumulation of Cr6+ was varried with temperature ,while the Cd2+ was constantly absorbed .
|
|
Received: 25 May 2014
|
|
|
|
|
|
|
