Ethereum mixer analysis is dominated by smart-contract pools. Tornado Cash is the reference typology: deposits into a pool contract, later withdrawals that break the visible link between depositors.
OFAC designated Tornado Cash in August 2022
The U.S. Treasury designation covered the Tornado Cash service and associated addresses after public reporting that the pool had processed very large volumes, including funds tied to Lazarus Group laundering. A direct deposit or withdrawal interacting with designated contracts is treated as severe mixer exposure in most exchange playbooks.
Commitment and nullifier patterns versus custodial tumblers
Contract pools leave on-chain deposit and withdrawal events without a simple input-output pair. Custodial ETH tumblers instead take custody and pay later. Detectors must match the mechanism; copying a Bitcoin CoinJoin rule onto a Tornado-style pool produces false confidence.
Relayers and fresh recipients
Withdrawals that use relayers and land on never-before-seen EOAs fit the pool design. Missing those features weakens an obfuscation claim even when some funds later touch a high-risk neighborhood. Record the route instead of upgrading every touch into intentional concealment.
Next step
Run the ETH wallet and review the pool path with hop context. Escalate unexplained direct Tornado-class contact under your compliance policy. This information is not legal or financial advice.