Eastman Chemical, maker of a BPA-free plastic resin alternative called Tritan, has sued two Austin, TX companies for publishing a study that shows a wide range of plastics exhibit estrogenic activity. The companies, PlastiPure and CertiChem, were both founded by University of Texas professor George Bittner. CertiChem tests plastic products for estrogenic activity, while PlastiPure makes estrogenic activity-free plastic products.