There is evidence to suggest that the presence of chlorine and chloramine compounds in municipal water (often deliberately added to retard bacterial growth) will cause deterioration of the internal chemical structure of polybutylene piping and the associated acetal fittings. The reaction with chlorinated water appears to be greatly accelerated by tensile stress, and is most often observed in material under highest mechanical stress such as at fittings, sharp bends, and kinks. Localized stress whitening of the material generally accompanies and precedes decomposition of the polymer. In extreme cases, this stress-activated chemical "corrosion" can lead to through perforation and leakage within a few years, but it also may not fail for decades. Fittings with a soft compression seal can give adequate service life.