Sulfhemoglobinemia is a rare condition in which there is excess sulfhemoglobin (SulfHb) in the blood. The pigment is a greenish derivative of hemoglobin which cannot be converted back to normal, functional hemoglobin.
In sulfhemoglobin, the sulphur atom prevents the iron from binding to oxygen, and since it's the oxygen-iron bonds that make our blood appear red, with sulfhemoglobin blood appears dark blue, green or black. Patients with sulfhemoglobinemia exhibit cyanosis, or a blueish tinge to their skin.
But blood actually comes in a variety of colors, including red, blue, green, and purple. This rainbow of colors can be traced to the protein molecules that carry oxygen in the blood. Different proteins produce different colors.
A rare condition in some people called sulfhemoglobinemia has blood that appears green, dark blue or even black. This condition is caused by exposure to excessive amounts of sulfur-containing compounds (or medications that contain sulfonamides).
For example, when our blood cells naturally die or get crushed, they produce bilirubin (yellow in color) and biliverdin (green) as they decompose. These are those lovely yellow and green marks around a bad bruise.
Pink Blood
Your blood may appear pink in color at the beginning or end of your period, especially if you're spotting. This lighter shade usually means that the blood has mixed with your cervical fluid. Sometimes pink menstrual blood may indicate low estrogen levels in the body.
Sometimes blood can look blue through our skin. Maybe you've heard that blood is blue in our veins because when headed back to the lungs, it lacks oxygen. But this is wrong; human blood is never blue.
Rh-null blood can be accepted by anyone with a rare blood type in the Rh system. “Golden blood” is as rare in reality as it was in ancient Greek mythology: only forty-three people in the world are known to have had this blood type.
One of the world's rarest blood types is Rh-null. Fewer than 50 people in the world have this blood type. It's so rare that it's sometimes called “golden blood.”
Blood does change color somewhat as oxygen is absorbed and replenished. But it doesn't change from red to blue. It changes from red to dark red. It is true that veins, which are sometimes visible through the skin, may look bluish.
Differentials of bright pink venous blood include cyanide and carbon monoxide poisoning, hypothermia, dyshaemoglobinaemias and lipaemia. Other aetiologies of abnormally coloured blood include methaemoglobinaemia (may appear brownish) and sulfhaemoglobinaemia (may appear darker red with a bluish hue).
Three siblings all carried two copies of a mutated gene, which caused their blood to run white with fat.
Greenish staining of human skin may result from a gamut of causes, such as chlorosis, exogenous copper, resolving ecchymosis, drugs, green textile dyes, green tattoos, apocrine and eccrine chromhidrosis, hyper biliverdinemia, chloromas, use of green dyes during tube feeding in patient with multiorgan failure, ...
Green skin, mucosa, nails, and hair may result from a multitude of etiologic factors; some are common, whereas others are medical curiosities. Green discoloration may be caused by exogenous agents or endogenous pigments and may result from conditions as innocuous as resolving bruise to serious systemic diseases.
When that copper is oxygenated, it is blue! So, some animals do have blue blood. But humans and other mammals always have red blood.
Famous Type O personalities: Queen Elizabeth II, John Lennon or Paul Newman.
Of the eight main blood types, people with Type O have the lowest risk for heart attacks and blood clots in the legs and lungs. This may be because people with other blood types have higher levels of certain clotting factors, which are proteins that cause blood to coagulate (solidify).
The new blood group is called Er or erantigens. There are five blood types in this group based on genetic variations of what's known as the Piezo1 protein, which is found on the surfaces of red blood cells.
Blood type A is the oldest, and existed even before the human race evolved from our ancestors.
What's the rarest blood type? AB negative is the rarest of the eight main blood types - just 1% of our donors have it. Despite being rare, demand for AB negative blood is low and we don't struggle to find donors with AB negative blood.
Are you still wondering why octopus blood is blue and what the three hearts do? Well, the blue blood is because the protein, haemocyanin, which carries oxygen around the octopus's body, contains copper rather than iron like we have in our own haemoglobin.
Darkened blood color is often observed in critically ill patients generally because of decreased oxygen saturation, but little is known about the other factors responsible for the color intensity. In addition, quantitative blood color examination has not been performed yet.
Blood that has been oxygenated (mostly flowing through the arteries) is bright red and blood that has lost its oxygen (mostly flowing through the veins) is dark red. Anyone who has donated blood or had their blood drawn by a nurse can attest that deoxygenated blood is dark red and not blue.