Trace elements and health: an overview

Area of Science:

• Environmental Health
• Geochemistry
• Human Nutrition

Background:

• Relating trace element imbalances in humans to geochemical factors is challenging compared to livestock.
• Human exposure pathways differ significantly from grazing animals, complicating direct environmental links.
• Technological advancements have altered the natural geochemical environment, impacting human trace element intake.

Purpose of the Study:

• To explore the difficulties in correlating human trace element status with geochemical factors.
• To examine the influence of technological changes on human exposure to environmental elements.
• To critically assess the evidence linking the physical environment to human health and disease.

Main Methods:

• Comparative analysis of human and animal trace element-environment relationships.
• Review of epidemiological data, particularly for endemic goitre.
• Examination of man-made modifications to the geochemical environment and their health implications.

Main Results:

• Endemic goitre serves as a key example of a geochemical link to human disease.
• Technological development significantly impacts human intake of essential and toxic elements like Iron (Fe), Iodine (I), Zinc (Zn), Lead (Pb), and Selenium (Se).
• Distinguishing between mere association and causation in environmental health studies requires rigorous criteria.

Conclusions:

• Establishing direct geochemical causality for human trace element disorders is complex.
• Human health is influenced by environmental factors, with technology playing a significant role in modifying these relationships.
• Understanding the chemical form and interactions of elements is crucial for setting safe tolerance limits.