Chlorine is likely associated with polyvinyl chloride (PVC), a widely used type of plastic that is of concern to the environment and public health during all phases of its life cycle. Flexible PVC contains chemicals called phthalates, some of which have been associated with decreased fertility, pre-term deliveries, and damage to the liver, testes, thyroid, ovaries, kidneys, and blood. There is also evidence that phthalates can pass from mothers to babies through the placenta and through breast milk.