title: Effect of chlorpyrifos on healing of cutaneous leishmaniasis lesions after treatment with Pentostam(®).
abstract: The insecticide chlorpyrifos (CPF) is widely used in the Kingdom of Saudi Arabia (KSA) to control agricultural pests. The present work is a preliminary investigation of the effect of CPF on healing of cutaneous leishmaniasis (CL) lesions, caused by Leishmania major in farmers exposed to this insecticide, after treatment with Pentostam(®). Lesion diameters were measured and CPF concentrations in the blood plasma of farmer and non-farmer CL patients in Al-Ahsa were detected by gas chromatography/mass spectrometry/mass spectrometry before and 6 weeks after treatment with Pentostam(®). CPF concentrations in the blood of farmer patients ranged between 4.570 and 7.096 ng/μl (mean = 6.19 ± 0.881 ng/μl) before and after treatment with Pentostam(®). The mean lesion diameter in these patients decreased by a factor of 2.21 after treatment with Pentostam(®); they measured 1.85-11.75 mm, (mean = 6.165 ± 3.500 mm) before treatment and 0.22-6.10 mm (mean = 2.796 ± 2.102 mm) after treatment. Lesion diameter increased exponentially with the increase of CPF concentration in the patients' blood. CPF was not detected in the non-farmer patients before or after treatment. Their mean lesion diameter decreased by a factor of 6.86 after treatment with Pentostam(®); they measured 1.33-7.10 mm (mean = 2.882 ± 1.764 mm) before treatment and 0.11-0.92 mm (mean = 0.425 ± 0.277 mm) after treatment. The mean lesion diameter in farmer patients was much greater than that of non-farmer patients both before (2.14×) and after (6.657×) treatment with Pentostam(®). Chronic exposure to low levels of the pesticide aggravates the development and delays the healing of CL lesions due to immunotoxicity and/or peripheral neurotoxicity caused by CPF. Further detailed studies would assess CPF effect on the severity of infection with CL in agricultural workers continuously exposed to this insecticide in different areas of KSA in conformity of their finding.
authors: Department of Zoology, College of Science, King Saud University, Riyadh, Saudi Arabia.
authors: Asya N
authors: AN
authors: Al-Dawood
authors: Ramadan A
authors: RA
authors: Al-Ghazal
authors: May H
authors: MH
authors: Al-Jaser
authors: Galila M
authors: GM
authors: Khalil
keywords: Chlorpyrifos; Cutaneous leishmaniasis; GC/MS/MS; Kingdom of Saudi Arabia; Leishmania major; Organophosphates; Pentavalent antimonials; Pentostam®
references: Environ Health Perspect. 2004 Feb;112(2):170-8
references: 14754571
references: Toxicol Sci. 2004 Aug;80(2):239-48
references: 15141101
references: Forensic Sci Int. 2001 Sep 15;121(1-2):126-33
references: 11516897
references: Ecotoxicology. 2003 Feb-Aug;12(1-4):345-63
references: 12739880
references: Regul Toxicol Pharmacol. 2006 Mar;44(2):111-24
references: 16360256
references: AIDS. 1991 Feb;5(2):201-7
references: 2031693
references: Parasitol Today. 1994 Jul;10(7):264-7
references: 15275441
references: Int J Dermatol. 1984 Apr;23(3):194-7
references: 6724777
references: Trans R Soc Trop Med Hyg. 1988;82(2):179-84
references: 3055447
references: Occup Environ Med. 2004 Mar;61(3):201-11
references: 14985514
references: Saudi Med J. 2005 Aug;26(8):1220-4
references: 16127517
references: Drug Metab Dispos. 1983 May-Jun;11(3):232-8
references: 6191937
references: Int J Infect Dis. 2004 Jul;8(4):244-50
references: 15234329
references: Trans R Soc Trop Med Hyg. 1987;81(4):529-33
references: 3445331
references: Trans R Soc Trop Med Hyg. 1989 Jul-Aug;83(4):493-8
references: 2617598