[Air pollution and biological defence (author's transl)]

Area of Science:

• Environmental Health
• Immunology
• Toxicology

Context:

• Individual susceptibility to air pollution varies significantly within populations.
• Growing evidence suggests these differences are linked to individual variations in biological defense mechanisms.
• Understanding these variations is crucial for public health and environmental policy.

Purpose:

• To review and synthesize existing experimental and epidemiological findings on the relationship between air pollution and human defense mechanisms.
• To highlight how air pollutants may compromise or alter immune functions.
• To underscore the connection between environmental exposures and health outcomes.

Summary:

• Inhalation of pollutants like nitrogen dioxide (NO2), lead, ozone (O3), and particulate matter can impair lung clearance and damage alveolar macrophages.
• Air pollutants can modulate immune responses, including complement activation (C'3 fraction) and lysozyme concentrations, potentially increasing infection susceptibility.
• Exposure to heavy metals and organic compounds may suppress the immune system, while also inducing allergic reactions and altering the metabolism of compounds like benzo(a)pyrene.
• Deficiencies in DNA repair mechanisms and adaptations to pollutants like carbon monoxide (CO) and sulfur dioxide (SO2) are also noted, with implications for cancer risk and allergic conditions.

Impact:

• Findings support a strong link between environmental pollution and the human body's defense systems.
• Highlights the need for further research into specific pollutant effects on immune function and individual susceptibility.
• Informs strategies for mitigating the health impacts of air pollution, particularly for vulnerable populations.