Rumors about the toxicity of ethoxyquin to fish sparked a backlash by consumers, according to a blog posted on petfood-connection.com.

The blog says that a 2005 reassessment of ethoxyquin, commissioned by the Environmental Protection Agency (EPA), states, "Studies indicate that ethoxyquin is toxic to aquatic invertebrates, and mildly toxic to fish" when ingested. This led to rumors that all fish foods contain the toxic ingredient because all fishmeal contains it, as well as Internet speculation by a fish food manufacturer claiming ethoxyquin could be hidden on an ingredients label if not used as a preservative in fish food.

However, there are sources of ethoxyquin-free fishmeal and the rumor about all fishmeal containing the toxic ingredient would apply only to certain fishmeal transported by boat. In addition, the second rumor is false, as any ethoxyquin content must specifically be stated on the label. According to the blog, the aquafeed and petfood industries must do more to control rumors such as these and better respond to meet the changing demands of consumers.