Received December 21, 2023
Accepted June 25, 2024

Exposure to ambient particulate matter ≤ 2.5 micrometer; PM 2.5 has a detrimental effect on health. There are scarce data on seasonal air pollution from the agricultural burning process. Objective: This study aimed to explore the correlation between ambient particulate matter 2.5 (PM2.5) concentration and sperm quality among northern Thai men who exposed to the seasonal air pollution from the agricultural burning process. Method: The demographic data and semen analysis of Thai men living in Chiang Mai, Thailand, who visited the infertile clinic were collected. The correlation test between the monthly amount of PM2.5 and sperm quality was carried out. Results: From 2017 to 2021, 1,109 Thai men visited the Infertile Clinic. The correlation test between PM2.5 and sperm quality in years with a better climate revealed a weak positive correlation between the mean PM2.5 and percentage of progressive motile sperm and normal morphology (r = 0.08, p = 0.05 and r = 0.1, p = 0.02). However, there was a negative correlation between the mean PM2.5 and sperm concentration, progressive motility and normal sperm morphology during the years with a higher amount of ambient PM2.5, and especially PM2.5 exposure 3 months before semen collection (r = -0.12, p = 0.01, r = -0.11, p = 0.003, r = -0.15, p = 0.004). Conclusion: Exposure to a high amount of PM2.5 air pollution negatively affects sperm quality.