In the biomedical industry, horseshoe crabs have been used in eye research, the manufacture of surgical sutures, and the development of wound dressings for burn victims. But perhaps most important is the use of a component of the horseshoe crab’s blood called Limulus Amebocyte Lysate (LAL), which is essential for the detection of bacterial endotoxins in drugs and intravenous devices.
The horseshoe crab plays a vital, if little-known, role in the life of anyone who has received an injectable medication. An extract of the horseshoe crab's blood is used by the pharmaceutical and medical device industries to ensure that their products, e.g., intravenous drugs, vaccines, and medical devices, are free of bacterial contamination.
To manufacture LAL, companies catch adult horseshoe crabs, collect a portion(1/3) of their blood, and then release them alive. Although this industry bleeds individuals and then releases the animals, two studies estimate 10 to 15 percent of animals do not survive the bleeding procedure, which accounts for the mortality of 20,000 to 37,500 horseshoe crabs per year.
|Unlike a human's blood, which is red, a horseshoe crab's copper-based blood is blue. - LINK|
|Horshoe crab bleeding. Photo credit: Andrew Tingle|
|Bled for LAL(Limulus amebocyte lysate test) - LINK|
|Photo credit: Courtesy of Thirteen/WNET/PBS - LINK|
|Photo credit: Jeff Rotman - LINK|
|A technician removes blood from horseshoe crabs. Photo credit: Andrew J. Martinez/Photo Researchers, Inc. - LINK|
Info from here