Both concrete and lye are alkaline substances with strong corrosive actions.
If either of these substances have been stuck to your hand for a long time, they will seep into the deeper layers of the skin and casue a deep chemical burn. Please consult your doctor for an examination to check for the depth and extension of the burn. It is possible that a burn which appears small and not very deep on the surface of the skin may actually be quite extensive under the upper layer of the skin.
Partial or full thickness burn of the skin can coontinue even after the concrete or lye has been washed off. If treatment is delayed, surgery may be needed to remove the dead and necrosed areas.
Please consult your doctor as early as you can. If you cannot consult anyone today, please go to the ER.
I hope this helps.
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