Plasma exposure levels of polycyclic aromatic hydrocarbons, pesticides and metals/metalloids among reproductive-age men in Jinhua, China: Influencing factors and links to semen quality

Reproductive health concerns related to environmental pollutants have gained significant attention, yet the link between blood exposure levels and male reproductive health is still not well understood. This study assessed plasma levels of polycyclic aromatic hydrocarbons (PAHs), pesticides, and metals/metalloids in reproductive-age men from Jinhua, China, and explored exposure-related factors and their associations with semen quality. The results showed that five PAHs (acenaphthene, fluorene, phenanthrene, fluoranthene, and pyrene) and two pesticides (p,p'-DDE and bifenthrin) were detected in plasma samples, with detection frequencies for individual compounds ranging from 21.2 % to 66.9 %. The mean exposure levels for PAHs and pesticides ranged from 31.91 to 277.97 ng/g lipids. For metals/metalloids, plasma concentrations ranged from 0.38 to 1539.03 ng/mL, with Hg at the lowest and Zn at the highest. These results revealed generally low to moderate levels of PAHs, p,p'-DDE, Hg, As, Se, Zn, Mn, Fe, and Cr, but elevated levels of Pb, Cd, Al, Ba, and Ni, indicating potential localized pollution concerns. Demographic and lifestyle factors significantly influenced pollutant exposure. Older individuals had higher levels of PAHs, Hg, and As, while fish consumption was linked to higher Hg and Se levels, and tea and fruit intake to higher pesticide exposure. Men with higher BMI exhibited elevated Hg levels, and stress influenced the concentrations of Fe, Zn and Ni. More importantly, significant associations were identified between pollutant exposure and semen quality, with elevated PAHs and Cr levels linked to reduced sperm concentration, and PAHs, Cr, and DDE levels negatively correlated with sperm viability. This study provides new insights into the relationship between plasma pollutant exposure and male reproductive health, and emphasize the need for targeted health interventions.