Thank you for your question. I am sorry to hear about your discomfort. Bleach particularly industrial strength bleach is a caustic substance meaning exposure to it can be caustic to whatever part of the body is exposed. Bleach also is caustic to your lungs and breathing in the fumes can cause irritation of the trachea and the surfaces of the lungs which in turn causes breathing difficulties and discomfort. Likely you chest pain is related to the lunch and airway being exposure to the fumes that bleach puts off when exposed. These effects can take a while to present, meaning that you may not feel any pain or discomfort until a while after exposure. The longer you are exposed the more your exposed areas will be irritated. It can affect your eyes, skin and anywhere else you may get exposed to the substance and direct exposure is often the most damaging. Finally often chest discomfort can involve the arms as well because of the way the nerves developed. If someone with heart problems is exposed they run the risk of exacerbating their underlying heart problems which is why it is advisable to these persons and really anyone to avoid exposure to caustic substances. Thanks, I hope this helps