In Vitro Toxicity to Two Cellular Systems of the First Ten Chemicals on the MEIC List
The cytotoxic effects of the first 10 chemicals on the MEIC list were evaluated with two experimental cellular systems, monolayer cultures of rat hepatocytes and cell lines (Hep G2 and 3T3). Three endpoints were measured to evaluate cytotoxicity, intracellular LDH activity, cellular protein content and the MTT test. The results show that: 1. digoxin, amitriptyline and diazepam were the most cytotoxic chemicals (IC50:0.01-0.5mM); 2. alcoholic compounds (sopropanol, ethylene glycol, ethanol and methanol) produced the lowest toxic effects (IC50: 100–1500mM); 3. paracetamol, acetylsalicylic acid and ferrous sulphate showed an intermediate cytotoxic action (C50: 0.05–15mM); 4. regarding the sensitivity of the cellular systems, paracetamol, acetylsalicylic acid, diazepam and ferrous sulphate were more toxic to rat hepatocytes, while digoxin produced a different toxic effect on hepatic and non-hepatic cells; and 5. the other chemicals did not show significant differences in their toxicity in the different cellular systems studied.