Pure natural rubber has poor ozone resistance. It will need stabilizing additives, and at least one of these (6PPD) has been found to have toxicity problems. h

Pure natural rubber has poor ozone resistance. It will need stabilizing additives, and at least one of these (6PPD) has been found to have toxicity problems. https://en.wikipedia.org/wiki/Ozone_cracking https://en.wikipedia.org/wiki/Ozone_cracking https://en.wikipedia.org/wiki/6PPD#Environmental_impact https://en.wikipedia.org/wiki/6PPD#Environmental_impact