Metal Toxicity and Speciation: A Review.

Area of Science:

• Environmental Science
• Toxicology
• Biochemistry

Background:

• Essential metal ions are vital for human metabolism; imbalances cause severe health consequences.
• Non-essential metals are not required for life and can be toxic upon exposure.
• Environmental contamination by toxic metals from natural and anthropogenic sources poses significant health risks.

Purpose of the Study:

• To review the toxicity of non-essential metals, focusing on their chemical properties and biological targets.
• To examine the mechanisms of toxicity for specific metals like mercury, lead, cadmium, chromium, nickel, and arsenic.
• To discuss chelation therapy as a potential treatment for metal poisoning.

Main Methods:

• Literature review of non-essential metal toxicity.
• Analysis of metal speciation and cellular targets based on chemical characteristics (e.g., hard-soft acid-base properties).
• Evaluation of therapeutic interventions, including chelation therapy.

Main Results:

• Non-essential metals exert toxicity by coordinating with biomolecules or displacing essential metals.
• Metals with redox properties can induce oxidative stress and cellular damage.
• Chelation therapy is an effective strategy for detoxifying toxic metal ions, especially in acute poisoning.

Conclusions:

• Toxic metals harm biological systems through coordination, displacement of essential metals, and induction of oxidative stress.
• Understanding metal chemical properties is crucial for predicting toxicity and speciation.
• Chelation therapy provides an effective clinical intervention for metal intoxication.