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Excavating the Mystery Whether it's Safe to Eat Horseshoe Crabs

Is it Safe to Eat Horseshoe Crabs?
The roe of horseshoe crabs is generally consumed although some species may be toxic. As a result, NutriNeat explains whether it is safe for consumption or not.
Praseeda Shirodkar
Last Updated: Mar 26, 2018
In Thailand
Yum Kai Meng Da is a horseshoe crab salad delicacy that is pretty famous. The roe is mixed with salad for that extra bite.
Horseshoe crabs are not actually crabs. Though they resemble crustaceans, they belong to a different sub-phylum (Chelicerata) and are closely related to scorpions, spiders, and prehistoric trilobites. They are harmless in nature and cannot bite. Moreover, the sharp tail that they possess is not for the purpose of defense. It is just for turning themselves upright if they happen to get turned over by chance.

As crabs are an edible delicacy all over the world, what about horseshoe crabs? Are they safe for consumption? It has been observed that there are specialist restaurants in places like Malaysia that have horseshoe crabs as an item on their menu.
The horseshoe crab has four species, which are Carcinoscorpius rotundicauda (or the mangrove horseshoe crab), Limulus polyphemus (or the Atlantic horseshoe crab), Tachypleus gigas, and Tachypleus tridentatus.
Carcinoscorpius rotundicauda
Carcinoscorpius rotundicauda crab
Limulus polyphemus
Limulus polyphemus crab
Tachypleus gigas
Tachypleus gigas crabs
Tachypleus tridentatus
Tachypleus tridentatus crab
Eggs of the Horseshoe Crab
Eggs of horseshoe crab
• Firstly, one needs to know that a horseshoe crab does not have any fleshy meat or parts that are edible except for its eggs or roe. This is the main food of most migratory birds, shorebirds, turtles, and other sea animals. The roe is located on the lower side of its body and may be green or orange in color. This roe is regarded to be an aphrodisiac in parts of Asia, causing it to be in demand. that too for a high price.
According to the taste (usually too salty and rubber-like), the orange roe is better than the green roe. However, some do prefer the green over the orange eggs.
Horseshoe crab salad
• Moreover, the eggs are what is mainly served in these restaurants. Sometimes, they are served in the horseshoe crab's shell itself. In this case, the whole horseshoe crab may be grilled and served on the plate from which you can remove the roe and consume it.
Spicy horseshoe crab egg salad
• There is also another serving style wherein the roe is mixed into salads. In this case, the horseshoe crab is placed in boiling water (about 3 minutes) instead of grilling. After it is allowed to cool, the roe is extracted and washed. The eggs are then mixed with salads or whatever is desired.
Now for the Not-so-good Part
• It is necessary to know that following the right procedure for the removal of roe, its cleaning, and preparation is essential. It actually plays a crucial role. This is because some species of horseshoe crabs are said to contain tetrodotoxin that is a powerful neurotoxin. Due to this, there is a possibility of tetratodoxin poisoning in humans on consumption, which can further result in death. Such cases of poisoning, leading to several deaths, have been observed in Thailand and Cambodia.

A widespread outbreak of poisoning resulted from the consumption of toxic eggs of the horseshoe crab in Chon Buri (Thailand). Around 71 people were affected, some showing symptoms of paresthesia, weakness, respiratory paralysis, vertigo, etc., and death in a few.

• Research studies state that this neurotoxin may be present only at certain times of the year. It was also stated that it is only present in the Carcinoscorpius rotundicauda or the mangrove horseshoe crab species that belong to Southeast Asia.

• Furthermore, it was observed that the consumption of Tachypleus tridentatus species may cause allergic reactions. However, this condition may be cured with chlorpheniramine. Thus, avoiding the consumption of horseshoe crabs, mainly the younger ones, was considered to be an effective prevention step.

• As mentioned above, apart from the roe there is hardly any edible flesh in horseshoe crabs. Even if there is a bit of something, its consumption is believed to cause dizziness.
Keep in Mind
Today, this dish may be available not only in Southeast Asia, but many other parts of the world. Testing kits are also available for the detection of tetrodotoxin. However, you need to remember that it is safe for consumption only when the correct procedure for cooking is followed; that is, when cooked by an expert. Thus, you should never try to prepare this dish on your own without prior experience. This is to avoid poisoning and rule out the possibility of any complications.

So, all one has to do is consume the edible portion so that it isn't harmful in any way. On the flip side, it has done a great deal of contribution to mankind. The following section enlightens you on that.
What's Special About its Blood?
• The blood of horseshoe crabs has enabled the testing of various intravenous drugs and other medical equipment due to the presence of LAL, a blood-clotting agent. This has helped save millions of human lives.

• Furthermore, research studies conducted on their eyes show an association with human optics. As a result, progress in the study of human optics can be achieved.

• Moreover, their shells have a component called chitin that is used in the production of dressings for burns. These dressings are capable of providing an effective and faster healing process. Due to this, these "crab-things" have gained a lot of importance.