Horseshoe crabs have existed for 450 million years.
Unlike us, they may have coexisted with dinosaurs at one time. Which is why
they are called living fossils. Horseshoe crabs have nine eyes- two compound,
and seven simple. Their name is deceptive. They are closely related to spiders
and scorpions. The world’s largest population is concentrated in the Delaware
Bay off the coasts of New Jersey and Delaware.
They are useful in at least three ways. First, they
are used as fishing baits. Nearly a million are caught and killed in the bait
fishery every year. Secondly, they help migrating birds survive. Guided by the full
moon, hundreds of thousands of horseshoe crabs gather on beaches across the US
mid-Atlantic to lay their eggs. The 9000 mile travelling birds, particularly
the Red Knot, are totally dependent on the fat content of those eggs to
maintain the energy required to fly further north.
The third, the most important use for us, is their
ability to detect harmful bacteria in drugs and vaccines.
*****
These primordial creatures are first transported to
labs. A horseshoe crab is plucked from the water tank. Its helmet-shaped shell
is bent in half to reveal a soft white membrane. A needle is inserted in to
draw blood. The blood is pure blue, because of its copper content. Nearly 30%
of blood is drawn out in this involuntary donation.
This blood has an invaluable talent for finding
infection. As soon as it comes into contact with endotoxin (a poisonous
substance), the blood clots. Since the 1970s, this property has been used to
apply a test known as LAL (Limulus Amebocyte Lysate). This distinctive blood
test is used for injectable drugs such as insulin, implantable medical devices
such as knee replacements, hospital instruments such as scalpels and IVs. The
presence of endotoxin, even in small amounts, in drugs or vaccines can be
fatal.
About 70 million endotoxin tests are performed every
year in a $ 1 billion market. The blood is so critical that its current price
is $16,000 per liter. Not jokingly, some refer to it as Blue Gold.
*****
This is the only natural thing known to us that can
test the safety of drugs and vaccines. In 2016, a synthetic alternative has
been developed in Europe. However, on 1 June 2o20, the American Pharmacopia,
which sets the standards for drugs and vaccines in the USA, declined any
alternatives, saying their safety is still unproven. Any Covid-19 vaccine, (and
currently hundreds of projects are working on it), to be sold in the USA must be
tested with the horseshoe crab blue blood.
*****
After drawing one third of the blood, the horseshoe crabs are sent home – back to the ocean. Even with the utmost care, the journey to the lab and back takes its toll. Nearly 30% die. The females’ ability to spawn may get impaired. Some studies have found the bled crabs becoming disoriented and debilitated for a long time. Environmentalists have expressed concerns that excessive blood testing may endanger this valuable species.
It is in our own interest that we take every measure
to ensure the survival and growth of horseshoe crabs.
Ravi
रक्तपिपासू माणूस
ReplyDeleteIf there is a synthetic alternative, then why not use it?
ReplyDeleteAmerican Pharmacopia, the authority to make such a decision, says they have 30+ years of experience with the horseshoe crab, but only two years with the synthetic alternative. Not long enough to have full trust.
Delete