While anthropogenic pollutants are known to be a threat to primates, our understanding of exposure to pollutants in situand their sub-lethal effects is still limited. We used noninvasive biomonitoring to examine associations between fecal concentrations of 97 chemical pollutants and fecal hormone metabolites of cortisol and estradiol in four primate species inhabiting Kibale National Park, Uganda (chimpanzees - Pan troglodytes, olive baboons - Papio anubis, red colobus - Piliocolobus tephrosceles, and red-tailed monkeys - Cercopithecus ascanius). Across all species (n = 71 samples), our results demonstrated positive associations of organochlorine pesticides (ß = 0.143, p = 0.020) and organophosphate esters (ß = 0.112, p = 0.003) with cortisol in adult females. Additionally, we observed positive associations of organochlorine pesticides (ß = 0.192, p = 0.013) and brominated flame retardants (ß  = 0.176, p = 0.004) with cortisol in juveniles. Our results suggest that cumulative pesticides and flame retardants are disruptive to endocrine function in these populations, which could have implications for development, metabolism, and reproduction. Our results further demonstrate that feces can be an important, noninvasive matrix for examining pollutant-hormone associations in wild primates and other critical wildlife populations.

Data include fecal samples collected from four species of primates inhabiting Kibale National Park, Uganda in 2017. Samples were quantified for steroid hormones and persistent organic pollutants using methods reported in the associated manuscript.