Perchlorate contamination in Chile: Legacy, challenges, and potential solutions

Area of Science:

• Environmental Science
• Toxicology
• Geochemistry

Background:

• Perchlorate is a widespread water contaminant known to inhibit thyroid function.
• Drinking water standards for perchlorate vary globally, with limits set in the United States and Europe.
• Chile possesses unique natural perchlorate deposits, primarily from Chile saltpeter in the Atacama Desert.

Purpose of the Study:

• To review the perchlorate contamination situation in Chile.
• To identify sources, environmental presence, and human exposure levels.
• To explore potential mitigation strategies for health impacts.

Main Methods:

• Review of existing literature on perchlorate contamination in Chile.
• Analysis of reported concentrations in environmental media and human samples.
• Assessment of potential natural sources and human uses contributing to contamination.

Main Results:

• High perchlorate concentrations detected in Chilean drinking water (up to 1480 µg/L), fruits (140 µg/kg), and wine (30 µg/L).
• Significant perchlorate levels found in human breast milk (100 µg/L) and neonatal serum (20 µg/L).
• Natural perchlorate deposits in the Atacama Desert have likely existed for millions of years.

Conclusions:

• Perchlorate contamination is a significant health concern in Chile, linked to natural deposits and fertilizer use.
• Further comprehensive surveys of perchlorate in Chilean ecosystems and food are necessary for risk assessment.
• Investigating perchlorate-reducing microorganisms in the Atacama Desert could lead to novel bioremediation strategies.