The chemical load of companion animals from a One Health perspective

Background Humans and companion animals are increasingly sharing lifestyles, indoor environments, physical activity levels, and eat processed food. The chemical exposome (pollution) produced by humans is a major concern of the One Health perspective. Anthropogenic pollution impacts the environment and animal health and, like a boomerang, returns to humans, where it may induce numerous diseases, as in a holobiontic system. The role of companion animals’ chemical exposome in the One Health framework is, however, less well understood. Here, we investigate the chemical exposome of companion animals, the associated toxicity risks, and discuss prevention. Methods This study uses non-invasive samples from four companion animal species. Chemical contaminants were classified according to their use category from the Norman Substance Database. Toxicity risks were assessed using the Globally Harmonized System of Classification and Labelling of Chemicals. As a first step for further prevention, a novelty of this study is the spatial localization of contaminants in animal tissues through mass spectrometry imaging. Results The 223 chemical contaminants detected varied in species and tissues, depending on the captivity status of the animal. Biocides were the most numerous contaminants; the main toxicity risks were irritant and environmental hazard. The cutting-edge spatial localization of chemical contaminants provided innovative results pointing toward prevention through remediation of the chemical sources for preserved animal, environmental, and human health. Conclusions From a One Health perspective, non-invasive companion animal biomonitoring may provide an entry point for identifying shared household chemical hazards and guiding source-directed prevention across animal, human, and environmental health.