Elastic and ball-point pens.

[Carey]

Believe it or not, the atmospheric acid increase from things like NOx from fossil fuel burning could have an effect on those elastics... & chlorine exposure, even when rinsed, can/does start polymer chain degradation, maybe rinsing slows the rate, but those bonds are broken in the presence of Chlorine! Even the atmospheric increase of ozone in the troposhere (rather than the much more heralded decrease in the stratosphere) can cause bloomers to become unstrung!