What is it?
This cornea has become opacified by an alkali burn. Most chemical substances that come in contact with the conjunctiva or cornea cause little harm. The chief danger comes from alkali-containing compounds found in household cleaning fluids, fertilizers and pesticides. They erode and opacify the cornea. Acid-containing compounds (battery fluid, chemistry labs) are somewhat less dangerous.
What to do?
There are no antidotes to these chemicals. The best you can do is to dilute them promptly with plain water.
Instill a topical anesthetic if the patient will not open the eyes because of pain, and irrigate with the handiest source of water for about 10-15 minutes. Squeeze bottles or saline drip bottles are a good choice. If the chemical is particulate, hold the eyelids widely apart with paper clip retractors, irrigate into the fornices, and wipe them clean with cotton-tipped applicators.
After the irrigation, check visual acuity. Instill fluorescein to check for epithelial defects. If acuity is subnormal, or there are epithelial defects, refer to an ophthalmologist. Otherwise, no further treatment is necessary.