The blood of the shroud
Scientific analyses of the reddish stains on the Shroud of Turin show they are human blood. In the early 1980s, researchers identified the blood as type AB. This blood type is uncommon, found in only about 3-5% of the world's population. Its distribution is geographically specific. While relatively rare among modern Europeans, it is more frequently found in populations from the Middle East.
Analysis of the bloodstains revealed other specific biological markers. Tests confirmed the presence of hemoglobin and serum albumin, components expected in real blood. The blood contains high concentrations of bilirubin, a yellowish pigment produced during the breakdown of red blood cells. Elevated bilirubin levels can occur in response to severe physical trauma. Some researchers propose this high bilirubin content could explain why the bloodstains have retained a reddish color over centuries, rather than turning the typical dark brown of old, dried blood. DNA analysis of dust particles from the shroud has also identified human genetic material with origins in the Near East and India.
A chronological contradiction
The scientific data is complex and sometimes conflicting picture. In 1988, three independent laboratories performed radiocarbon dating on a small sample cut from the edge of the shroud. The results were consistent across the labs, yielding a date range of 1260–1390 AD for the linen's origin. This places the cloth squarely in the Middle Ages, coinciding with its first undisputed historical appearance in Lirey, France, around 1355.
Other lines of physical evidence challenge the medieval dating. The linen itself is a high-quality, 3:1 herringbone twill weave. While some textile experts argue this type of loom was not common until the medieval period, others note that similar complex weaves have been found in first-century contexts, such as at the Masada fortress in Israel.
Microscopic analysis of dust and fibers taken from the shroud's surface reveals a collection of ancient pollen grains. In the 1970s, Swiss criminologist Max Frei identified pollen from 58 different plant species. Many of these pollens are from plants native to Europe, but a significant number belong to species endemic to the Middle East, including some found almost exclusively in the region around Jerusalem and the Dead Sea. The combination of blood type, pollen evidence, and textile characteristics fuels scientific debate about the shroud's true age and geographic history.