Dieldrin's pesticide registration was cancelled by EPA under FIFRA, and it is listed as a Persistent Organic Pollutant under the Stockholm Convention, to which the US is a signatory. Any import would require EPA authorization and would be subject to TSCA Section 13 import certification. In practice, legitimate commercial imports are extremely rare and would likely be limited to reference standards or research quantities with appropriate regulatory approvals.

Because dieldrin is a regulated substance under both FIFRA and TSCA, CBP will typically require an EPA TSCA import certification (positive or negative) at entry. Shipments lacking proper certification or EPA authorization are subject to refusal of admission and re-export. Importers should obtain written guidance from EPA's Office of Pesticide Programs before any attempted entry.