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.
Increased pressure to the eye is often a cause of broken blood vessels. Going upside down on a roller coaster, being inverted in a yoga pose for too long, or even the increased pressure pressure in an airplane can be causes for increased pressure to the eye resulting in a broken blood vessel.