About Blood Stains

Blood stains are one of the hardest types of stains to remove due to the proteins and enzymes in blood. These enzymes bond to the fabric or other stained material and can only be removed by treatment with an enzyme-based cleaning solution. Blood stains are dark due to the deoxygenation of the hemoglobin, which is responsible for the color in blood.

History

Blood stains have played an important role in the history of violent crime. Blood can stain everything from concrete to clothing, so it is almost always found at a crime scene. However, until modern science equipped forensics with the technology to determine DNA from a blood stain, it was impossible to link the blood with an individual. Forensics could determine blood type from a blood stain, but that was as much information as they could glean from the sample.

Features

A blood stain is an organic stain because it is composed of organic matter that contains proteins. Blood is red due primarily to the presence of hemoglobin. When hemoglobin interacts with different molecules, it changes the color of the blood. This is why blood exits the body a bright red color, yet creates blood stains that are dark red. Highly oxygenated blood makes the hemoglobin bright red, and deoxygenated blood causes the hemoglobin to turn much darker in color.

Time Frame

Whether blood spilled on a fabric becomes a permanent stain involves a number of factors, the most important factor being time. If the blood is given enough time to dry completely, it is pretty much guaranteed to become a permanent blood stain. This is due to the proteins in the blood having enough time to bond with the natural proteins in the fabric.

Identification

A blood stain can be identified visually by its trademark dark red color. However, in order to officially identify a stain as a blood stain it would need to be subjected to protein testing. Lab tests can also determine the blood type of the blood stain, as well as the DNA makeup of the blood stain, which can be traced back to the person it came from.

Prevention/Solution

Blood can be prevented from staining a fabric if treated quickly and properly. Since blood contains natural enzymes, it reacts differently to treatment than many other types of stains, and a specific protocol should be followed. Never rinse the stain with warm water, as the enzymes will react and set the stain in the fabric. This is also why blood stained fabric should not be put in the dryer - even if the stain looks like it is almost gone, the high heat can set it permanently in the fabric.
The proper way to solve blood stain issues is to rinse the stain with cold water. Once the blood spot has been thoroughly rinsed with cold water, treat the spot with an enzyme-based fabric cleaner. Using an enzyme-based cleaner is crucial, since the cleaner enzymes will work to break up and dissolve the blood's enzymes. Allow the stain to soak before washing it in cold water with the same cleaner as the detergent. Finally, allow to air-dry in a cool location to avoid any further setting.