Tungsten contamination, behavior and remediation in complex environmental settings.

Area of Science:

• Environmental Science
• Toxicology
• Geochemistry

Background:

• Tungsten (W) is a rare element found in minerals like wolframite and scheelite.
• Industrial applications of tungsten include filaments, X-ray tubes, electrodes, and radiation shielding.
• Tungsten's high density makes it suitable for defense applications, potentially replacing lead.

Purpose of the Study:

• To review current knowledge on tungsten pollution in terrestrial and aquatic ecosystems.
• To link tungsten pollution to its natural and anthropogenic sources, behavior, and health hazards.
• To explore remediation strategies for tungsten-contaminated environments.

Main Methods:

• Literature review of scientific studies on tungsten pollution.
• Analysis of tungsten's chemical behavior in soil and water (oxidation states, speciation).
• Evaluation of environmental and human health risks associated with tungsten exposure.

Main Results:

• Tungsten exists mainly as tungstate anion in soil, with prevalent oxidation state +6.
• Tungsten alloys and particulates pose health risks, including carcinogenicity.
• Exposure routes include inhalation, ingestion, and dermal contact, particularly in occupational settings.

Conclusions:

• Remediation strategies include stabilization (immobilization) and solubilization (mobilization) of tungsten.
• Stabilization prevents tungsten bioavailability and food chain transfer.
• Solubilization facilitates tungsten removal through soil washing and root absorption.