Affiliations: School of Biotechnology, Chemical and Biomedical
Engineering VIT University, Vellore-632 014, Tamil Nadu, India | Auxilium Women's College, Vellore - 632 006 | Division of Human Genetics, Department of Animal
Science, Bharathiar University, Coimbatore, 641046
Abstract: In the present study the effect of heavy metals, mercury and copper,
on plasma electrolytes viz., sodium, potassium and chloride have been
investigated in economically important fish Cyprinus carpio var. communis. C.
carpio were exposed to sub-lethal levels of mercury (0.03 ppm) and copper
(0.096 ppm) under strict identical hydro-physiochemical conditions. Significant
decline in these three electrolytes were observed when fish were exposed to
sub-lethal levels of mercury chloride and copper sulphate during chase period
of 7, 14, 21, 28 and 35 days. The decrease in sodium ions was proportional to exposure time in
mercury with maximum observed decrease of 33.0% on 35th day, whereas a maximum
decrease of 66.36% was noted on 7th day in copper. Plasma potassium level of
Cyprinus carpio var. communis declined continuously in the mercury treated fish
showing a maximum per cent decrease of 54.68 at the end of the 28th day. The
plasma chloride level observed a maximum decrease of 46.02% and 80% at the end
of 7th day in the mercury and copper-treated fish respectively. The
mercury-treated fish maintained the percent decrease of 22.56, 36.98, 38.08 and
39.02 on the 14, 21, 28 and 35th days. However, in the plasma chloride level in
copper-treated fish a gradual recovery during subsequent exposure periods was
observed giving a per cent decline of 61.23%, 45.39%, 34.02% and 10.11% at the
end of the 14th, 21st, 28th, and 35th days, respectively. Hence, results
indicated that pollutants including toxic heavy metals and useful micronutrient
when a safe level exceed are reflected by the decrease in the plasma
electrolytes of fish. The electrolyte levels in fish can be used for
biomonitoring and Ecological Risk Assessment.
Keywords: Cyprinus carpio, electrolytes, heavy metals, mecury, copper biomonitoring and ecological risk assessment
