At issue is BPA, or bisphenol A, a widely used compound that often serves as an additive in the production of polycarbonate, a hard type of plastic commonly used in consumer products, like reusable water bottles. The chemical has proved highly useful in making items sturdier, leading to its widespread use. But scientists and public health groups have worried for years that BPA, an endocrine disruptor that affects human hormones, poses risks for fetal development and to people, including infants and children. Other concerns include increased blood pressure, Type 2 diabetes and cardiovascular disease.