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.
Sometimes these abnormal vessels grow from the retina into the vitreous cavity and leak blood, causing a vitreous hemorrhage. Mechanical damage to the blood vessels of the retina can occur from a retinal tear or trauma to the eye. Like any other part of the body, if a blood vessel gets damaged, it will start to bleed.