ORIGINAL ABSTRACT

ABSTRACT: Pesticides are a major source of endocrine-disrupting chemicals (EDCs) in agriculture that threaten both reproductive function and ecosystem health. Once applied, pesticides spread beyond their intended treatment area, infiltrating soil and water systems, where non-target species can be exposed. Domestic livestock frequently encounter endocrine-disrupting pesticides in farming environments; however, the effects this exposure has on livestock productivity and reproduction are poorly understood. This review explores the mechanisms through which common insecticides and herbicides disseminate and break down, being the first to consolidate all known metabolites and residues of these chemicals and their persistence and degradation in different matrices. We consider the bioaccumulation and toxicological impacts of pesticides in terrestrial and aquatic ecosystems and how their exposure can impair reproductive function. Organophosphates, carbamates, pyrethroids, neonicotinoids, atrazine, and glyphosate were commonly found to cause reproductive dysfunction in both the male and female through interruptions of hormone function and synthesis and through oxidative stress. Pesticides pose a significant risk to livestock and wildlife through disruptions to reproduction, and given that agricultural resilience and productivity is dependent on the health and function of surrounding ecosystems, the disruptions pesticides cause threaten the ecological balance of agroecosystems. Moving forward, the cumulative impact pesticides and metabolites have on the reproduction of non-target species of livestock, wildlife, and humans must be considered when conducting toxicological assessments of pesticides in addition to their persistence and degradation in agroecosystems. Further research is required to understand how pesticide-induced endocrine disruption affects livestock reproduction. LAY SUMMARY: EDCs are chemicals that interfere with normal hormone production and function. A significant source of EDCs in the environment stems from the use of certain pesticides and herbicides used in food production. Several of the active compounds used for pest management can affect fertility and reproduction in humans, livestock, and wildlife. In agricultural systems, it is unlikely that EDCs remain on farm, as these compounds can move through soil and water, accumulate in plants or animals, and eventually enter the human diet. These pathways link farm management practices to broader environmental and health outcomes. This review explores how EDCs behave and persist within agricultural ecosystems, how they affect reproductive function across species, and how residues can circulate through food chains and adjacent ecosystems. Understanding these interactions helps identify where interventions can reduce exposure and safeguard reproductive health in both agricultural land and natural ecosystems.