Endocrine-Disrupting Chemicals and Their Effects in Pet Dogs and Cats: An Overview

SIMPLE SUMMARY: Endocrine-disrupting chemicals (EDCs) are environmental pollutants with heterogeneous chemical structures and various sources that, once absorbed by the body, can interfere with endogenous hormonal actions. Extensive studies have been conducted correlating EDC exposure and human health, and interest in their effects on the health of domestic pets is increasingly becoming an issue of public concern. Dogs and cats can be exposed to EDCs in indoor and outdoor domestic environments through ingestion, inhalation, and transdermal absorption, with diet considered the primary source. Their exposure has been associated with several health disorders comparable to those described in humans, including thyroid and reproductive disorders, diabetes, heart and kidney diseases, and various types of cancer. The human–pet relationship implies sharing much of the same environment, thus including exposure to EDCs. Therefore, dogs and cats have been suggested as potential sentinels for human environmental exposure to contamination. It is becoming clear that exposure to EDCs is a matter of concern for pet health just as for humans, and the impact of this has been boosted by the growing attention to pet well-being. Any move towards a “risk-sharing” attitude in public health could, thus, benefit both humans and animals. ABSTRACT: Over the past few decades, several pollutants classified as environmental endocrine-disrupting chemicals (EDCs) have become a matter of significant public health concern. Companion animals play a major role in human society, and pet ownership is substantially increasing worldwide. These intimate human–pet relationships imply sharing much of the same environment, thus including exposure to similar levels of EDCs in daily routine. Here, we review the current knowledge on the sources and routes of exposure to EDCs in domestic indoor and outdoor environments and discuss whether endocrine disruption is a health concern in pets. We summarize the phenomenon of endocrine disruption, providing examples of EDCs with a known impact on dog and cat health. Then, we propose an overview of the literature on the adverse effects of EDCs in domestic pets, with a special focus on the health of reproductive and thyroid systems. Finally, we explore the potential role of companion animals as unintentional sentinels of environmental exposure to EDCs and the implications for public health risk assessment in a “shared risk” scenario. Overall, this review supports the need for an integrated approach considering humans, animals, and the environment as a whole for a comprehensive assessment of the impact of EDCs on human and animal health.