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.
The blood vessels just under the covering of the white of the eye are small, and breaking one of these blood vessels does not require much effort. A common cause for a broken blood vessel in the eye is straining.