Polychlorinated biphenyls (
PCBs) are persistent
environmental pollutants and known to act as xenoestrogens.
PCBs and
diethyl phthalate (
DEP) are ubiquitous
environmental pollutants because both are used as
plasticizers and in various other industrial applications. Therefore, a study was undertaken to evaluate the interactive toxicity of
DEP and
PCBs in young female Wistar rats. Healthy young female albino rats of Wistar strain weighing 100g (7-8 weeks old) were randomly assigned to five groups of six each. Group I female rats were fed on normal diet and water ad libitum. Group II female rats were maintained on normal diet mixed with
corn oil at 16.5mg/kg diet/day and 0.94mg/kg
body weight/day as oil control. Groups III and IV female rats were given
Clophen A60 and
DEP dissolved in
corn oil mixed with the diet at 50mg/(kgdietday), which is approximately equal to 2.85mg/(kgbodyweightday), individually to each group. Group V female rats received a mixture of
DEP and
Clophen A60, each dissolved in
corn oil mixed with the diet at 50mg/(kgdietday), which is approximately equal to 2.85mg/(kgbodyweightday). Treatment was carried out for 150 days and after the completion of treatment, serum and liver
enzymes and other biochemical parameters in the serum and liver were assessed. Liver weight to
body weight ratio showed significant increase in
Clophen A60 and Clophen A60+DEP treated rats. In the three treated groups, there was significant decrease in liver
glutathione (GSH) and
glutathione reductase (GR).
Alanine amino
transferase (ALT) was significantly increased in the liver of the three treated groups and in the serum of
Clophen A60 and
DEP alone treated groups and significant decrease only in the serum of Clophen A60+DEP treated rats. Significant increase in liver and serum
lactate dehydrogenase (LDH) and
acid phosphatase (ACP) activity was observed in the three treated groups.
Alkaline phosphatase (ALP) activity was significantly increased only in the serum of the
Clophen A60 and Clophen A60+DEP treated rats, whereas significant decrease in the serum and liver of
DEP alone treated rats was observed.
Aspartate aminotransferase (AST) activity and
cholesterol levels were highly significant in the liver and serum of
DEP treated rats. In addition,
cholesterol level was significantly increased in the liver and serum of
Clophen A60 treated rats and only in the liver of Clophen A60+DEP treated rats.
Succinate dehydrogenase (SDH) activity was significantly increased in the liver of
Clophen A60 and Clophen A60+DEP treated rats and highly significant increase in the serum of Clophen A60+DEP treated rats. There was significant increase in
triglyceride levels in the liver and serum of
Clophen A60 and Clophen A60+DEP treated rats, whereas significant increase in
triglyceride levels in the serum of
DEP alone treated rats was observed.
Glycogen levels were significantly increased in the liver of Clophen A60+DEP treated rats, whereas serum
glucose levels showed significant decrease, but in
Clophen A60 alone treated rats showed significant increase in
liver glycogen and serum
glucose, whereas
DEP alone treated rats showed significant increase in only serum
glucose levels. Lipid peroxidation was increased in the liver of
DEP treated rats, which was highly significant, compared to significant increase in
Clophen A60 and Clophen A60+DEP treated rats. Histology of liver showed severe vacuolation, loss of hepatic architecture and granular deposits in the hepatocytes of
DEP and Clophen A60+DEP treated rats, whereas in
Clophen A60 alone treated rats, hepatocytes showed hyper pigmentation mild loss of hepatic architecture in centrilobular and periportal area.