title: Spectrophotometric determination of plasma and red blood cell cholinesterase activity of 53 fruit farm workers pre- and post-exposed chlorpyrifos for one fruit crop.
abstract: We sought to investigate the early biological effects of chlorpyrifos among 53 Thai fruit farm workers by measuring the plasma cholinesterase (PChE) and red blood cell cholinesterase (AChE) activities, a biomarker of organophosphate (OPs) pesticide during one fruit crop. The ChE activity (V(m)/K(m)) was spectrophotometrically analyzed before and after exposing to chlorpyrifos. The V(m)/K(m) values of both non-spraying and spraying seasons are found as normal distribution pattern. The median PChE and AChE activities among farm workers in the non-spraying season were 2.3 x 10(-3) s(-1) and 7.26 x 10(-5) s(-1), respectively. The median PChE and AChE activities of the farm workers in the spraying season were 2.02 x 10(-3) s(-1) and 5.95 x 10(-5) s(-1), respectively. The mean V(m)/K(m) values of PChE shifted left (t-test, p=0.013), indicating a decrease in PChE activity in the farm workers exposed to chlorpyrifos. However, the V(m)/K(m) values of AChE in nonspraying season and in the spraying season were not different (t-test, p=0.246). We propose that PChE activity can be used as a biomarker for monitoring early toxicity induced by chlorpyrifos insecticide.
authors.affiliation: Department of Industrial Hygiene and Safety, Faculty of Public Heath, Burapha University, Chonburi, Thailand.
authors.forename: Anamai
authors.initials: A
authors.lastname: Thetkathuek
authors.forename: Matthew
authors.initials: M
authors.lastname: Keifer
authors.forename: Wijitr
authors.initials: W
authors.lastname: Fungladda
authors.forename: Jaranit
authors.initials: J
authors.lastname: Kaewkungwal
authors.forename: Chantana
authors.initials: C
authors.lastname: Padungtod
authors.forename: Barry
authors.initials: B
authors.lastname: Wilson
authors.forename: Samlee
authors.initials: S
authors.lastname: Mankhetkorn
mesh_terms: D000293:Adolescent; D000328:Adult; D000383:Agriculture; D004390:Chlorpyrifos / Q000009:adverse effects*; D002800:Cholinesterase Inhibitors / Q000009:adverse effects*; D002802:Cholinesterases / Q000097:blood*; D004912:Erythrocytes / Q000187:drug effects / Q000201:enzymology*; D005260:Female; D005638:Fruit; D006801:Humans; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure / Q000009:adverse effects*
chemical_list: D002800:Cholinesterase Inhibitors; D002802:Cholinesterases; D004390:Chlorpyrifos