Release of arsenic from metal oxide sorbents under simulated mature landfill conditions

• Non-redox sensitive sorbents leach arsenic to an equal or greater extent than a ferric sorbent.
• Fe, Ti, Zr and La sorbents leach arsenic exceeding the Toxicity Characteristic.
• Arsenic solid retention increases along a decreasing reduction activity gradient.
• La retained a greater fractional proportion of its initial arsenic load than other sorbents due to a higher pHpzc.