EFFECTS OF SELENIUM, IRON AND ZINC SUPPLEMENTATION ON ARSENIC CONCENTRATION IN TISSUES WITH GROSS PATHOLOGY IN LONG EVANS RATS

Abstract

The study was carried out to know the effects of selenium, iron and zinc supplementation on gross pathology and tissue arsenic concentration in Long Evans rats during the period from August to October 2003. A total of 25, one-month-old male rats were randomly divided into 5 equal groups as A, B, C, D and E. Rats of group A were kept as control without giving any treatment. Rats of groups B, C and D were given normal rat pellet (25 g / rat / day) and in addition to arsenic trioxide (As2O3) @ 400 mg / litre, they were treated with sodium selenite (NaSe) @ 1 mg / litre, ferrous sulfate (FeSO4) @ 150 mg / litre and zinc sulfate (ZnSO4) @ 50 mg / litre respectively while rats of group E were treated with only arsenic trioxide (AS2O3) 400 @ mg / litre drinking water daily for 42 days. All the rats of groups B, C and D showed slight congestion in the liver, spleen, heart and kidney and haemorrhage in stomach and intestine but the rats of group E showed heavy congestion in the liver, spleen, heart and kidney and rose-red inflammation in the stomach and severe haemorrhagic enteritis. Among the treated groups, the rats of groups B (0.0126-0.27 ppm), C (0.03-0.32 ppm) and D (0.04-0.288 ppm) which were supplemented with sodium selenite, ferrous sulfate and zinc sulfate respectively along with arsenic trioxide showed reduced arsenic concentrations in different tissues while the rats of group E treated only with arsenic trioxide showed higher concentrations of arsenic in tissues (0.05-0.4 ppm). The concentration of arsenic in the liver, kidney, spleen, heart, stomach, intestine, muscle and dermis of the treated rats were 0.27-0.40 ppm, 0.06-0.22 ppm, 0.052-0.20 ppm, 0.0126-0.102 ppm, 0.054-0.16 ppm, 0.064-0.176 ppm, 0.028-0.07 ppm and 0.03-0.05 ppm respectively. It may be concluded that supplementation of selenium, iron and zinc reduces the arsenic concentration in tissues like liver, kidney, spleen, heart, intestine, stomach, muscle and dermis of rats as well as lower the tissue damage caused by arsenic. The present results also indicate that arsenic is deposited mainly in liver followed by kidney, spleen, dermis, heart and muscle.