Question

local reaction will occur at the site of the exposure, such as irritations or damage to the skin, eyes or lungs.

Answer 1

The word "local" will mean the surrounding area of an exposed site. This should be frequent in the area that exposed to an external environment like skin, lung, eye, mouth.

This reaction is caused by white blood cells, called inflammation. The irritation might kill the cells and release its content that will activate white blood cells.