A Striking Degree of Abnormal Cell Growth (image) Brown University Caption This image shows mammary tissue of control mice (left) and mice exposed as fetuses to 1,000 mg per kg of mother's body weight of MEHP, a common ingredient in plastics. (Black bar is 1 mm.) Credit Hixon Lab/Brown University Usage Restrictions Please credit. Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.