Horseshoe Crab Blood Is Blue And Worth $15,000 A Litre

Its copper-based blood detects bacteria — and pharma bleeds it.

Reviewed by the CurioVault curator · 8 October 2026 · Editorial standards

Horseshoe Crab Blood Is Blue And Worth $15,000 A Litre — AI illustration — Image generated by CurioVault AI — copyright free

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Horseshoe crabs use hemocyanin (copper) not hemoglobin (iron), so their blood is bright blue. It contains Limulus Amebocyte Lysate (LAL) that clots on contact with bacterial endotoxin. Since the 1970s, every vaccine and implant is tested with it. Crabs are bled (30% of blood) and released, but up to 30% die. A litre is worth ~$15k. Synthetic alternatives now exist but uptake is slow.

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#horseshoe-crab #blood #medicine #blue-blood #pharma

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