Lack of promoting activity of four pesticides on induction of preneoplastic liver cell foci in rats

Abstract

Four pesticides were examined for hepatopromoting activity using a medium-term bioassay based upon induction of glutathione S-transferase placental form (GST-P) positive foci in the rat liver. Male F344 rats were initially injected with diethylnitrosamine (DEN; 200 mg/kg body weight) intraperitoneally and 2 weeks later were treated with O-ethyl O-4-nitrophenyl phenylphosphonothioate (EPN; 75 and 150 ppm), diazinon (500 and 1,000 ppm), phenthoate (500 and 1,000 ppm), or iprobenfos (500 and 1,000 ppm) in the diet for 6 weeks and then killed, all rats being subjected to partial hepatectomy at week 3. All of the pesticides gave negative results, the numbers and areas of GST-P positive foci not exceeding the control values for animals given DEN alone. Indeed, a significant reduction of foci development was seen for EPN (75 ppm). These findings provide experimental evidence that the presently examined four pesticides do not have hepatocarcinogenic potential in rats.

Antimicrobial activity of essential oils and their components against the three major pathogens of the cultivated button mushroom, Agaricus bisporus

“…However, it is suggested that they may cause side effects, including carcinogenicity, teratogenicity and residual toxicity, although this seems very doubtful scientifically (Kato et al, 1995;McCarroll et al, 2002). The use of most of the synthetic fungicides has been restricted in many countries since the early sixties of the last century.…”

Chemical characterization of Lippia alba essential oil: an alternative to control green molds

“…Although the fungicides that are commonly used in cultivation are very effective and inexpensive, it has been suggested that they leave residual toxicity that may cause side effects, including carcinogenesis and teratogenesis (20,23,33 (28). An additional advantage of essential oils is their volatile nature, which implies on low or no residues after treatment and low environmental impact.…”