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Toxics2025; 13(12); 1064; doi: 10.3390/toxics13121064

Sentinel Equines in Anthropogenic Landscapes: Bioaccumulation of Heavy Metals and Hematological Biomarkers as Indicators of Environmental Contamination.

Abstract: Environmental contamination with heavy metals, resulting from industrialization, urbanization, and agricultural intensification, poses serious ecological and health risks. Horses, due to their grazing behavior and close association with human environments, serve as reliable sentinel species for assessing environmental pollution. This study aimed to evaluate the bioaccumulation of heavy metals and trace elements in different biological matrices of horses-blood, hair, hooves, and synovial fluid-and to investigate their relationship with hematological biomarkers as indicators of physiological stress. Samples were collected from horses raised in anthropogenically influenced areas and analyzed using inductively coupled plasma mass spectrometry (ICP-MS). Hematological parameters were determined with an automated analyzer to assess systemic effects. The results revealed significant variations in metal concentrations among matrices, with keratinized tissues reflecting long-term exposure, while blood and synovial fluid indicated recent contamination. Correlations between elevated metal levels and altered hematological values suggested oxidative stress and adaptive physiological responses. These findings demonstrate the value of multi-matrix biomonitoring in evaluating both environmental quality and animal health. Horses effectively reflect the cumulative impact of heavy metal exposure, supporting their role as bioindicators within a One Health framework that links environmental, animal, and human well-being.
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Publication Date: 2025-12-09 PubMed ID: 41441284PubMed Central: PMC12737071DOI: 10.3390/toxics13121064Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

Overview

  • This research studied horses living in human-impacted environments to measure heavy metal accumulation in their bodies and how it affects their blood health markers.
  • The goal was to use horses as indicators to better understand environmental contamination and its biological effects.

Background and Purpose

  • Industrialization, urbanization, and intensified agriculture have increased environmental contamination by heavy metals.
  • Heavy metals pose ecological risks and threaten health in humans and animals.
  • Horses, due to their grazing habits and close contact with human environments, can serve as sentinel species to monitor pollution levels.
  • The study aimed to measure heavy metal and trace element bioaccumulation in various horse biological samples to assess exposure and physiological impact.
  • It also investigated how metal exposure correlates with changes in hematological biomarkers, indicating stress or health effects.

Methodology

  • Samples collected included blood, hair, hooves, and synovial fluid from horses raised in areas influenced by human activities.
  • Heavy metal and trace element concentrations were measured using inductively coupled plasma mass spectrometry (ICP-MS), a sensitive analytic technique.
  • Hematological parameters (e.g., blood cell counts, hemoglobin levels) were analyzed with an automated blood analyzer to detect systemic physiological effects.
  • The multi-matrix approach allowed distinguishing between recent and long-term exposure by comparing levels in different tissues.

Key Findings

  • Significant differences in heavy metal concentrations were observed between biological matrices:
    • Keratinized tissues (hair, hooves) reflected long-term heavy metal exposure due to their slow growth and metal incorporation over time.
    • Blood and synovial fluid showed levels representing more recent exposure to contaminants.
  • Correlations emerged between elevated heavy metal levels and altered hematological biomarkers, indicating:
    • Oxidative stress caused by metal toxicity.
    • Physiological adaptations or damage in response to environmental pollution.
  • These results highlight that horses effectively accumulate and reflect environmental contamination, validating their use as bioindicators.

Significance and Implications

  • The study supports using a multi-matrix biomonitoring strategy to comprehensively assess both environmental quality and animal health.
  • Demonstrates the usefulness of hematological biomarkers as indicators of physiological stress linked to pollutant exposure.
  • Positions horses as sentinel animals within the One Health framework, emphasizing the interconnectedness of environmental health, animal health, and human health.
  • Findings can inform pollution monitoring programs, environmental risk assessments, and health surveillance in anthropogenically affected regions.

Cite This Article

APA
(2025). Sentinel Equines in Anthropogenic Landscapes: Bioaccumulation of Heavy Metals and Hematological Biomarkers as Indicators of Environmental Contamination. Toxics, 13(12), 1064. https://doi.org/10.3390/toxics13121064

Publication

Toxics
ISSN: 2305-6304
NlmUniqueID: 101639637
Country: Switzerland
Language: English
Volume: 13
Issue: 12
PII: 1064

Researcher Affiliations

Conflict of Interest Statement

Ioan Valentin Petrescu-Mag was employed by Bioflux SRL. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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