Pesticide Exposure and Alzheimer’s Disease: A Case-control Study

Aim / Objective: This study aimed to investigate the levels of organochlorine pesticides (OCPs) in the serum of Alzheimer's disease (AD) patients. Methods: 63 AD patients and 50 healthy individuals participated, and the levels of some OCPs derivatives (including; α-HCH, β-HCH, γ-HCH, 2,4-DDT, 4,4-DDT, 2,4-DDE, and 4,4-DDE), total antioxidant capacity (TAC), protein carbonyl (PC), malondialdehyde (MDA), Nitric oxide (NO) along with the activity of superoxide dismutase (SOD), glutathione peroxidase (GPx), paraoxonase 1(PON1), and acetylcholinesterase (AChE) were measured. Results: The mean OCP level of OCPs in AD patients was significantly higher than in the control group. However, the patients' mean levels of TAC, PC, MDA and activity of SOD, GPx, PON1 and AChE were significantly lower than controls. A significant positive correlation was also observed between 2,4-DDE and MDA and between γ-HCH and PC in AD patients. These findings showed that pesticide exposure is associated with an increased risk of AD. Furthermore, the mean levels of oxidative stress markers, which may result from pesticide exposure, were significantly lower in AD patients compared to healthy individuals. Conclusion: Therefore, it may conclude that pesticides, at least in part, contribute to AD development through several mechanisms, including the induction of oxidative stress.