Legitimate imports are essentially limited to certified analytical reference standards used in environmental monitoring laboratories to detect mirex residues in soil, water, or biological samples. Any such import should be accompanied by documentation from the supplier confirming the material is a reference standard and specifying the quantity, which will typically be measured in milligrams rather than kilograms.

As an Annex A listed substance, mirex is subject to elimination obligations, and exporting parties to the Convention must apply prior informed consent procedures. At US entry, CBP may refer the shipment to EPA for review under TSCA authority. Importers should obtain an EPA import determination in advance and ensure all entry documents clearly identify the substance by CAS number and intended use.