- The immediate management step when a toxic substance accidentally comes into contact with the eyes is to flush the eyes with copious amounts of water for at least 15 minutes.

This is critically important because:
- Rapid dilution and removal of the toxic substance minimizes ongoing chemical injury to the delicate ocular tissues.
- Irrigation with water or saline helps to reduce eye pain and prevent further damage by physically washing out the irritant.
- Delaying irrigation to apply medications or neutralizing agents can exacerbate injury, as many chemical reactions in the eye occur quickly.
- It is essential to keep the affected eye open during flushing to ensure thorough cleansing of the conjunctival sac and corneal surface.

- Using specific neutralizing solutions or topical antibiotics may be considered later under medical supervision, but they are not the immediate priority.
- Covering the eyes without irrigation may trap the chemical and worsen the injury.

In summary, the key immediate step is copious irrigation with water for at least 15 minutes, followed by prompt medical evaluation.

Reference: Toxicology: Principles and Practice, Volume 1, Chapter 3, Page 45