[anonymous]

Below is an excerpt from the comment section http://skeptvet.com/Blog/2011/07/vitamin-k3-menadione-in-pet-food-is-it-safe/
click on link for full article and comments

“Toxicity of menadione or its derivatives is reached at levels exceeding the requirements by a factor of at least 1 000.The use of MSB and MNB in animal nutrition does not pose a risk to the environment. MSB and MNB are regarded as effective sources of vitamin K in animal nutrition”.