Pesticide exposure and rhinitis: A cross-sectional study among farmers in Pitsanulok, Thailand

Background: Pesticide exposure has been suspected to cause rhinitis, a common disease that affects the health and wellbeing of millions of people around the world. The objective of this cross-sectional study was to examine the association between pesticide use and rhinitis prevalence among farmers in Phitsanulok province, Thailand.   Methods: Data on pesticide use and rhinitis use were collected by an in-person interview questionnaire. Data from 9,649 participants were included in the analysis. The association between pesticide exposure and rhinitis was determined by multiple variable logistic regression, adjusted for potential confounding factors.  Results: It was found that 6.3% of study participants had rhinitis, which was defined as having one or more of the following symptoms: sneezing, runny nose, and nasal congestion, within the past year.  The study found each type of pesticide (insecticides, herbicides, fungicides, rodenticides, molluscicides) to be significantly associated with rhinitis, with the odds ratio ranging from 1.67 (95% CI 1.41-1.99) for the fungicide group to 7.19 (95% CI 4.67-11.06) for insecticide. For individual pesticides, the study found 33 out of 35 to be significantly associated with rhinitis with the OR values ranging from 1.30 (95% CI 1.00-1.69) for alachlor to 5.67 (95% CI 3.16-10.16) for Bordeaux mixture.  Conclusions: This study found a prevalence of rhinitis among farmers in Phitsanulok, Thailand to be associated with the long-term exposure of many individual pesticides. This finding was consistent with other literature. Effects of pesticide on rhinitis should receive more attention from the public health and other organizations responsible for the farmers’ health.