Search

The aim of the study was to assess the maternal toxicity of polychlorinated naphthalenes (PCNs) and embryotoxic, fetotoxic, and teratogenic effects after administration of the PCN mixture to pregnant rats in four (0.3-9.0 mg/kg bw) daily doses during organogenesis (days 6-15 of gestation). For dams, a dose of 0.3 mg/kg bw, administered during organogenesis, has been established as NOAEL of PCNs, and a dose of 1 mg/kg bw, administered in the same period, as LOAEL. The dose-related fetotoxic (reduced body weight and length of the fetus, extension of renal pelvis and lateral brain ventricles, signs of delayed ossification and retardation in development of internal organs), and teratogenic effects (cleft palate and hydronephrosis) were recorded at all dose levels, also at the dose non-toxic to mothers. PCNs have been concluded to be potent fetotoxic and teratogenic agents producing similar effects to those of other toxic dioxin-like compounds.

The aim of the study was to investigate the toxicity of hexachloronaphthalene (HxCN) and its effect on cytochrome P-450 in rats and to make a comparison between HxCN and tetrachloronaphthalene (TeCN), an inactive congener. Our study provided evidence that the anorectic effect, with concurrent significant increase in relative liver mass was the most spectacular symptom of the toxic effect of hexachloronaphthalene in the rats after its single (250 mg/kg) and repeated (1 and 10 mg/kg) administration. Regardless of the kind of the experiment (acute or subacute toxicity), dose-dependent increase in lipid peroxidation in the liver was also observed, which may indicate that HxCN most probably generates oxidative stress in this organ. It was also observed that HxCN is a very strong inducer of cytochrome P-450, especially of CYP 1A, which is the most sensitive biomarker of exposure to this congener. In this study, LOAEL is 1 mg HxCN/kg b.w.

The aim of the study was to investigate the subacute toxicity of a polychlorinated naphthalene (PCN) mixture and its effect on cytochrome P-450 levels in rats. The animals were administered PCNs intragastrically in repeated daily doses of 1, 10, and 100 mg/kg. The animals were dissected after 7, 14, or 21 doses. Doses of 10 and 100 mg/kg induced a significant decrease in the body weight at all time points of the experiment compared with the control group. The exposure to PCNs increased both the level of total cytochrome P-450 and the activity of CYP 1A at the same time points. In the groups of rats given PCNs in doses of 10 and 100 mg/kg, an evident dose- and time-dependent increase in malondialdehyde (MDA) level was observed throughout the experiment. The correlation between the increased MDA and decreased glutathione (GSH) levels in the liver was also observed.