Fenbendazole Reference Standards

HPC supplies fenbendazole (CAS 43210-67-9) and D3-fenbendazole as neat and 100 µg/mL reference materials. Current EU MRLs apply to a defined sum of residues, not to fenbendazole alone.

Product	Catalog No./ CAS No.	Quantity	Price
ISO 17034 Reference Material D3-Fenbendazole	679390 1228182-47-5	1X10MG	Please log in.
ISO 17034 Certified Reference Material D3-Fenbendazole solution Concentration: 100 µg/ml Solvent: Acetonitrile	690855 1228182-47-5	1X1ML	Please log in.
Fenbendazole	674886 43210-67-9	1X100MG	Please log in.
ISO 17034 Certified Reference Material Fenbendazole solution Concentration: 100 µg/ml Solvent: Acetonitrile	683377 43210-67-9	1X5ML	Please log in.

Identity and analytical relevance

Fenbendazole is a benzimidazole anthelmintic used in veterinary medicine. Residue-control methods must account for the legally defined marker residue rather than assuming that a fenbendazole-only result represents the full regulated residue.

CAS Registry Number: 43210-67-9
Molecular formula: C₁₅H₁₃N₃O₂S
Molecular weight: 299.3 g/mol

EU marker residue and maximum residue limits

The consolidated Annex to Commission Regulation (EU) No 37/2010, current on 14 May 2026, defines the marker residue as the sum of extractable residues that may be oxidised to oxfendazole sulfone. For all food-producing species except fin fish, the listed MRLs are 50 µg/kg in muscle, 50 µg/kg in fat, 500 µg/kg in liver, 50 µg/kg in kidney, 10 µg/kg in milk and 1,300 µg/kg in eggs. For porcine and poultry species, the fat value relates to skin and fat in natural proportions.

These are matrix-specific legal MRLs for the defined marker residue. They are not general toxicity limits and should not be reported as limits for fenbendazole alone.

Health-assessment basis

In the EMA assessment supporting the extension of MRLs to further food-producing species, the theoretical daily intake calculated from the proposed residue limits was 400 µg per person per day. This represented 95.2% of the acceptable daily intake of 420 µg per person per day used in that assessment. The calculation describes the 2013 regulatory assessment; it is not a dosing recommendation.

Available HPC reference materials

The current range includes fenbendazole as neat material (item 674886, 100 mg) and as a 100 µg/mL solution in acetonitrile (item 683377, 5 mL). D3-fenbendazole is available neat (item 679390, 10 mg) and as a 100 µg/mL solution in acetonitrile (item 690855, 1 mL).

Primary sources and review status

Regulatory information reviewed on 16 July 2026. Confirm the current matrix, species, marker-residue definition and jurisdiction before applying an MRL.