Two senators have asked the US Food and Drug Administration (FDA) to increase its oversight of petfood after a lawsuit accused Nestle Purina’s Beneful of harming and killing dogs.

Sens. Dianne Feinstein, D-California, and Dick Durbin, D-Illinois, sent a letter to FDA asking it to investigate the claims and to provide an update on how it is implementing previous laws that require contamination prevention measures in petfood.

“To put it frankly, the food safety system Congress fought to develop has not been put in place by the FDA,” the senators wrote in the letter addressed to FDA Commissioner Margaret Hamburg.

A class action lawsuit was filed February 4 by a California man alleging that Purina added propylene glycol, an automotive antifreeze component, to Beneful, causing illness and death to his dogs.

In response to the suit, Nestle Purina said: “We at Beneful want you, our valued customers, to know that this lawsuit is baseless; you can continue to feel confident feeding your dogs our food. We stand committed to our Brand, our products and your pets.”

The class action claims that the defendants have received more than 3,000 online complaints about their food making dogs sick throughout the past four years. In some cases, the dogs reportedly suffered internal bleeding, weight loss, dehydration and other symptoms. The suit alleges negligence, misrepresentation, product liability and unfair business practices. The plaintiff is seeking more than $5 million in damages, plus costs and fees.

“To our knowledge, the FDA has not issued any investigations, warnings, consumer guidance, or product recalls to address these alarming issues,” the senators wrote.

The letter cites the FDA Amendments Act of 2007, which requires various changes such as improving regulations for petfood safety, strengthening labeling requirements, establishing an early warning system for contaminated products, and setting ingredient and processing standards.

“However, eight years later, most provisions of the petfood safety law have not been implemented and protections Congress enacted are not in place, amid allegations of contaminated Beneful dry kibble,” the senators wrote.

 The eight kinds of dry Beneful food scrutinized in the lawsuit are Purina Beneful Healthy Smile, Healthy Fiesta, Healthy Growth for Puppies, Healthy Radiance, Healthy Weight, Incredibites, Original and Playful Life.