What substance will help denature the toxin from a jellyfish sting?

Vinegar is effective in denaturing the toxins from a jellyfish sting because it has acetic acid, which can help neutralize the venom, particularly from species like the Box jellyfish. The application of vinegar can prevent the release of additional toxins from the nematocysts (stinging cells) that may still be on the skin after a jellyfish sting.

The acidic nature of vinegar is fundamental in inactivating the toxins and providing relief, as it can help to stabilize the proteins within the venom. In contrast, other substances such as ammonia, bleach, or alcohol could potentially exacerbate the situation by increasing the activation of nematocysts or causing additional irritation to the skin, rather than providing relief from the sting. Therefore, vinegar is recognized as a straightforward and effective first aid measure for treating certain types of jellyfish stings.