Abstract
In this study, the great pond snail Lymnaea stagnalis has been exposed to three different media to investigate the effect of aqueous aluminium (Al) on mortality and respiration. The media in question are acidic Al-rich (pH 5.8), acidic Al-poor (pH 5.8) and untreated natural water (pH 7.2) as control. Mortality trials were unfortunately canceled due to great difficulties with the detection of mortality.
When looking at normoxic O2- consumption and critical O2- tension, I found statistically significant differences between the different exposure media and between some of the chambers. Great pond snails exposed to acidic Al-rich medium had a significant lower normoxic O2-consumption and higher critical O2-tension compared to exposures acidic Al-poor- and control media. The condition for Al-polymerization was not optimal, and aluminium analyses show that in the acidic Al-rich medium, the Al-polymerization gradient did not occur as expected. I did , however, have a high concentration of Al at its most toxic fraction (Ali) ranging from 510 ± 106 μg/L to 666 ± 180 μg/L.
Within the exposure channel containing Al-rich medium, there was no significant decrease of normoxic O2-consumption or increase of critical O2-tension with water residence time My results support that aqueous aluminium is affecting respiration in L. stagnalis, but there is no evidence that the degree of Al-polymerization has any effect on respiration.
