Anurak Wongta, Environmental and Occupational Health Sciences and Non-communicable diseases Center of Excellence. Research Institute for Health Science, Chiang Mai University, Chiang Mai 50200 Thailand
Surat Hongsibsong, Environmental and Occupational Health Sciences and Non-communicable diseases Center of Excellence. Research Institute for Health Science, Chiang Mai University, Chiang Mai 50200 ThailandFollow
Zhen Lin Xu, Guangdong Provincial Key Laboratory of Food Quality and Safety, College of Food Science, South China Agricultural University, Guangzhou, 510642, People’s Republic of China
Somporn Chantara, Environmental Chemistry Research Laboratory, Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai, 50200, Thailand
Mookda Pattarawarapan, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
Ratana Sapbamrer, Department of Community Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
Korawan Sringarm, Department of Animal and Aquatic Science, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand
Nootchakarn Sawarng, Environmental and Occupational Health Sciences and Non-communicable diseases Center of Excellence. Research Institute for Health Science, Chiang Mai University, Chiang Mai 50200 Thailand
Phannika Tongjai, Environmental and Occupational Health Sciences and Non-communicable diseases Center of Excellence. Research Institute for Health Science, Chiang Mai University, Chiang Mai 50200 Thailand


Background: Organophosphate pesticide (OP) exposure may be associated with the subsequent development of cognitive decline, which is used to assess the early stage of Alzheimer’s disease. We investigated the correlations between biomarkers of OP exposure and cognitive decline among farmers and nonfarmers.

Methods: Blood samples were collected from 98 participants. Biomarkers of OP exposure were analyzed, including acetylcholinesterase enzyme (AChE) and butyrylcholinesterase enzyme (BChE) activity. Cognitive decline was measured using the Thai Mental State Examination.

Results: The average AChE and BChE activity levels were 3.94±0.93 units/ml (mean ±SD) and 3.13±0.88 units/ml, respectively. Being employed in agricultural occupations were positively correlated with cognitive decline, even after adjustment for sex, age, and educational level (odds ratio: 5.469, 95% CI 1.012-29.55). There was significantly lower AChE activity in participants who had used pesticides for more than 10 years. There was also a positive correlation between low AChE activity and cognitive decline in the study population.

Conclusion: The monitoring of exposure biomarkers may be useful in investigating the risk of cognitive decline in at-risk groups.


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