Neurotoxic and General Effects of Combined Subchronic Exposure of Rats to Insecticides and Heavy Metals
Three different insecticides: dimethoate, cypermethrin and amitraz were given, alone or combined with the heavy metals Pb, Hg and Cd, to male Wistar rats per os for 12 weeks from their 4th week of life. After the treatment period, the left hemisphere of the rats was exposed in urethane anaesthesia, and spontaneous and evoked cortical activity was recorded from the primary sensory areas. The effects of dimethoate on the spontaneous activity, and of dimethoate and amitraz on the evoked responses, were increased by the metal combination treatment, whereby the metals alone had no effect on the spontaneous and mild effect on the evoked activity. Finally, the animals were dissected, organ weights measured, and relative organ weights calculated. The weight gain of all treated groups was significantly retarded compared to the control. Several organ weights were also significantly reduced, mainly in groups receiving insecticide plus metal treatment. The toxic interactions observed in this work indicate that combined human exposure to environmental pesticide residues and heavy metals may have unexpectedly severe effects.
Keywordsheavy metal insecticide combination neurotoxicity rat
Unable to display preview. Download preview PDF.
Supported by an OTKA grant, No. T042955.
- 8.Dési, I., Nagymajtényi, L., Schulz, H., Papp, A. (1998) Experimental model studies of pesticide exposure. NeuroToxicol. 19, 611–616.Google Scholar
- 10.Elinder, C. G. (1985) Cadmium: Uses, occurrence and intake. In: Friberg, L., Elinder, C. G., Kjellström, T. (eds) Cadmium: Uses, Occurrence and Uptake, vol. 1. CRC Press, Boca Raton, Florida, pp. 23–64.Google Scholar
- 13.Gralewicz, S., Tomas, T., Górny, R., Kowalczyk, W., Socko, R. (1991) Changes in brain bioelectri-cal activity (EEG) after repetitive exposure to an organophosphate anticholinesterase. II. Rat. Polish J. Occup. Med. Environ. Healt. 4, 183–196.Google Scholar
- 14.Grandjean, P. (1978) Regional distribution of lead in human brains. Toxicolog. 2, 65–69.Google Scholar
- 19.Jiang, H. M., Han, G. A., He, Z. L. (1990) Clinical significance of hair cadmium content in the diagnosis of mental retardation of children. Chin. Med, J. (Engl., 103, 331–334.Google Scholar
- 24.Muttray, A., Padberg, F., Jung, D., Rohlfing, H. R., Schulz, M., Konietzko, J. (1996) Acute changes in human EEG after exposure to low doses of oxydemeton methyl. Centr. Eur. J. Occup. Environ. Med. 2, 367–378.Google Scholar
- 25.Nagymajtényi, L., Schulz, H., Papp, A., Dési, I. (1997) Behavioural and electrophysiological changes caused by subchronic lead exposure in rats. Centr. Eur. J. Occup. Environ. Med. 3, 195–209.Google Scholar
- 27.Papp, A., Pecze, L., Vezér, T. (2002) Central neurotoxic effects elicited with three organophosphorus compounds: comparison of acute and subchronic administration. Fiziologia (Timisoara. 12, 19–24.Google Scholar
- 28.Papp, A., Pecze, L., Vezér, T. (2005) Acute effects of lead, mercury and manganese on the central and peripheral nervous system in rats in combination with alcohol exposure. Arh. Hig. Rada Toksikol. (Zagreb. 56, 241–248.Google Scholar
- 29.Papp, A., Vezér, T., Pecze, L. (2002) Effects of inorganic and organic mercury on cortical and hip-pocampal activity in rats. Centr. Eur. J. Occup. Environ. Med. 8, 118–125.Google Scholar
- 31.Schulz, H., Nagymajtényi, L., Papp, A., Dési, I. (1997) Behavioural and neurophysiological consequences of subchronic mercury exposure in rats. Centr. Eur. J. Occup. Environ. Med. 3, 210–223.Google Scholar
- 37.Winneke, G., Altmann, L., Kramer, U., Turfeld, M., Behler, R., Gutsmuths, F. J., Mangold, M. (1994) Neurobehavioral and neurophysiological observations in six year old children with low lead levels in East and West Germany. NeuroToxicol. 15, 705–713.Google Scholar
This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.