DALLAS, TX – An online petition has reportedly collected more than 50,000 digital signatures calling for Whataburger to stop using foam cups. The petition was posted on Environment Texas and claims that one third of foam cups end up in rivers, lakes, and oceans.

“For a bird or fish or turtle, it’s easy to mistake a small piece of polystyrene for food. When animals ingest plastic waste, it can block their digestive tracts. As a result, they starve,” the petition states. “Polystyrene is one of the worst and most common types of plastic. Americans throw out 70 million polystyrene foam cups every day.”

Environment Texas is an Austin-based environmental advocacy project. The organization focuses on numerous issues, including tropical forest protection, solar energy, and lead exposure. Officials from the organization hand delivered the petition and a letter to Whataburger’s San Antonio headquarters Monday, the Dallas Morning News reported.

“At Whataburger, we’re always looking for the best way to serve our customers and we value their feedback,” Whataburger said in a statement provided to the Morning News. “We continue to look at cup alternatives that keep drinks at the right temperature, but we have a lot to consider from a quality and supply perspective when meeting our customers’ expectations. We will share any updates if we have news to share. In the meantime, we continue to urge customers to properly dispose of our cups.”

Q&A: Petition against styrofoam delivered to Whataburger