Horseshoe crab blood: Supporting responsible practices in pharma and healthcare
- Post Date
- 29 December 2024
- Read Time
- 4 minutes
The first interesting thing about a horseshoe crab is, it isn’t a crab. It’s more closely related to a spider and other arachnids. Next up is how long these strange creatures have been around. Fossils dated at 445 million years old show they have barely changed over this period, making them one of the oldest animals on the planet, significantly predating dinosaurs.
Horseshoe crab blood is a bright blue colour and has a special quality that makes it incredibly important to human health. The blood contains an enzyme (amebocyte lysate) which coagulates when exposed to bacterial endotoxins, which can cause sickness or even death in humans. As such, pharmaceutical companies use horseshoe crab blood to test medicines and vaccines for safety.
The crabs are captured from the wild and drained for their blood, after which they are released, live, back into the coastal waters they inhabit. The impact of this process on the crabs’ health and behaviour is contentious. Companies relying on the horseshoe crab population to supply the pharmaceutical sector say that their conservation efforts are supporting the crabs’ ecosystem, reporting low mortality rates and a quick rebounding of blood levels in crabs after draining.
However various challenges have been made to the industry on the ethics of the practice, the accuracy of the mortality rates and also the hard-to-measure impact on the crabs’ breeding and egg-laying seasons. The crabs’ eggs are of particular concern as an important food source for birds, notably the migratory red knots in the US and other shorebirds. It is also important to note that, unlike the American horseshoe crabs, the Asian horseshoe crab population is a registered endangered species.
In recent years, various less-intensive testing methods have become available, meaning that less horseshoe crab blood is used to carry out the test. Most suppliers of endotoxin testing now offer a less-intensive testing option – though at higher cost versus traditional methods. Additionally, a synthetic alternative has been developed and has been approved for use across most major markets. This means that a drug can be guaranteed as safe for human consumption without the need for any horseshoe crab blood.
As with many ethical and environmental challenges that face business, this presents a challenge – how to distribute the commercial burden of adopting more sustainable practices and enable the whole industry to change. This is where the Pharmaceutical Supply Chain Initiative (PSCI) comes in. A collaboration of over 80 pharma and healthcare sector companies spread across Europe, North America and Asia, including both buyers and suppliers of endotoxin tests. Aware of the issue in part due to pressure from the asset managers BNP Paribas, PSCI brought it members together in 2022 to discuss the issue and find a path forward. Out of those discussions came the PSCI Position Paper on the Use of Horseshoe Crabs [1]. Published May 2023, the paper set out to encourage companies to minimise their use of the horseshoe crabs and to seek out safe alternatives for their supply chains.
The paper outlines good practices and encourages members to adopt these, specifically:
- Protect all endangered species and cease further collection from the Asian horseshoe crab population.
- Minimise the use of horseshoe crab blood in the endotoxin testing process, whether through minimisation techniques or through the use of synthetic alternatives.
- Understand the animal welfare and conservation position, taking an active and intentional approach to sourcing, knowing where their endotoxin tests come from and the conservation and biodiversity considerations that may result.
In turn PSCI itself committed to:
- Monitor and review members’ approach on this and report it on an anonymised basis.
- Engage with others to learn and develop particularly on the US conservation position.
- Prepare guidance, materials, and support to members and suppliers to implement the good practice elements in the position paper.
Many companies are now working to embed these points into their practices and take up company positions on the topic as well as switching to less intensive or synthetic test methods. PSCI is tracking progress amongst its members and the first progress report will be published in January 2025.
PSCI is an independent non-profit organisation established in the US and governed by its members. PSCI’s Secretariat has been provided by SLR since 2015.
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References
[1] https://pscinitiative.org/resource?resource=1939
