The extent of the «rust» or oxidation is dependent on how long the oxygen is in contact with the substance. (robdaquila.com)
When the skin comes into contact with the substance over and over, the immune system «remembers it» and develops an itchy skin response. (nationaleczema.org)
You'll notice the signs on the parts of her body making direct contact with the substance — around her neck, on her belly, legs or feet. (happytailsspa-blog.com)