After you fire up the barbecue grill, the charcoal briquettes you use as fuel are eventually reduced to a pile of charred remains and ashes. This residue contains recycled plant material and naturally occurring minerals, but it may also contain harmful chemicals.
Burst blood vessel in the eye. Straining, coughing or injuring your eye can sometimes cause a blood vessel to burst on the eye surface, causing a bright red blotch. This is called a subconjunctival haemorrhage.
Other Causes of Bleeding in the Eye. 1  Sickle cell disease: Sickle cell anemia is an inherited blood disorder that is characterized by chronic anemia and intermittent pain. It is caused by abnormally shaped blood cells that have difficulty transporting hemoglobin and oxygen throughout the body.