Limitation of the study:
1. Subjective symptoms may be caused by other pesticides.
2. Evidence of pesticide-related symptoms was relied on self-report without
physical examinations or clinical interview.
3. Budget and time limitation so the sample size was small.
4. The cross-sectional study design was limited to determining the causal
associations of significant predictors and blood cholinesterase levels.
5. The standard normal ChE level from American people was use in this study.It would be better if ChE level with the standard normal from Thai people
was used.
6. This study was focused only on OP pesticides. Other carbamates and some herbicide maybe used in this area but not included in the study. Therefore,
the report of symptoms might be influenced by other pesticides.