title: Genotoxic and cytotoxic effects in the bone marrow of rats exposed to a low dose of paraquat via the dermal route.
abstract: The genotoxic effect of the herbicide paraquat was studied in rat bone-marrow by means of the micronucleus assay. Paraquat at dose levels of 6, 15 and 30 mg/kg body weight was given to rats in a single application via the dermal route. Marrow was collected at 24, 48 and 72 h after the application. The micronucleus assay was done as recommended by standard procedures. Paraquat gave rise to an increase in the number of micronuclei in a dose-dependent manner. The number of micronucleated polychromatic erythrocytes showed a maximum at 48 h and the toxicity was further prolonged, as there was no complete recovery at 72 h. These findings suggest a genotoxic effect of paraquat even after exposure via dermal application.
authors.affiliation: Department of Physiology, School of Medical Sciences-PPSP, Universiti Sains Malaysia, 16150 Kubang Kerian, Kota Bharu, Kelantan, Malaysia. dsouza@kb.usm.my
authors.forename: Urban J A
authors.initials: UJ
authors.lastname: D'Souza
authors.forename: Anuar
authors.initials: A
authors.lastname: Zain
authors.forename: Sivachandra
authors.initials: S
authors.lastname: Raju
mesh_terms: D000279:Administration, Cutaneous; D000818:Animals; D001853:Bone Marrow / Q000187:drug effects*; D002875:Chromosomes / Q000187:drug effects; D003603:Cytotoxins / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004912:Erythrocytes / Q000166:cytology / Q000187:drug effects; D006540:Herbicides / Q000008:administration & dosage / Q000494:pharmacology; D006801:Humans; D008297:Male; D015162:Micronucleus Tests; D009153:Mutagens / Q000494:pharmacology*; D010269:Paraquat / Q000008:administration & dosage / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D003603:Cytotoxins; D006540:Herbicides; D009153:Mutagens; D010269:Paraquat