Utilizing urinary biomarkers in Egyptian adolescent applicators and non-applicators to characterize pesticide exposure to λ-cyhalothrin, α-cypermethrin, chlorpyrifos and profenofos applied on cotton crops over time
Date of Degree
PhD (Doctor of Philosophy)
First Committee Member
Second Committee Member
Third Committee Member
Fourth Committee Member
Fifth Committee Member
Organophosphates (OPs) and Pyrethroids (PYRs) are widely used pesticides in both agricultural and non-agricultural environments. In agricultural work settings, typically more than one pesticide is used in combination, or sequentially, to kill pests. There is currently a gap in research that looks at how exposures to multiple pesticides can impact human health – particularly among adolescents who work in these environments. The goal of this dissertation research was to examine the use of OP (chlorpyrifos, and profenofos) and PYR (λ-Cyhalothrin, α-Cypermethrin) pesticides across an application season and how exposure is associated with symptoms and cholinesterase enzyme activity, and to examine the impact of a sequential exposure to multiple OPs, and exposure to both OPs and PYRs. Urine and blood samples, questionnaire data, and a medical exam were collected over a 10-month period from adolescent pesticide applicators in Egypt. Overall, applicators had higher exposure than non-applicators to all four pesticides. The non-applicators were also exposed and had levels 4 times higher in urine metabolite levels than the general population in the U.S. In addition, these exposures caused increased symptoms and severity of symptoms among both applicators and non-applicators. In conclusion, adolescent agriculture workers in the Egyptian cotton fields are exposed to multiple pesticides and are susceptible to the impact of those exposures on their health.
Adolesecents, Agriculture, Biomarkers, Cholinesterase, Occupational Exposure, Pesticides
xx, 161 pages
Includes bibliographical references (pages 140-161).
Copyright © 2018 Barbara C. Okeke
Okeke, Barbara C.. "Utilizing urinary biomarkers in Egyptian adolescent applicators and non-applicators to characterize pesticide exposure to λ-cyhalothrin, α-cypermethrin, chlorpyrifos and profenofos applied on cotton crops over time." PhD (Doctor of Philosophy) thesis, University of Iowa, 2018.