Is it safe to use raw mushrooms to flavor a broth? I'm following a recipe for making ramen broth. It says to use chicken stock and boil it with several fresh ingredients for 30 minutes to flavor it, one of which is mushrooms. 

Being a very inexperienced cook I searched online for how to handle mushrooms for cooking. One of the pages I found is by the Norwegian food safety authority and says that mushrooms should be put in cold water and brought to a boil, letting them boil for 10 minutes to remove toxins in them, and that this should be done even if you plan on frying the mushrooms afterwards. It also specifically says that the water used to boil the mushrooms should always be thrown away, I'm guessing because the toxins gets mixed into the water when you boil the mushrooms.

My question is, would these toxins not get into the my broth if I am putting the raw mushrooms directly into it? The recipe says nothing about boiling the mushrooms before hand, or is this just something I should know to do?

I also see a lot of recipes for mushroom sauces/soups which says to put raw mushrooms directly into the dish as it is being made, would this not have the same problem?`

I am using common white button mushrooms (Champignon).
In Norway lots of people still pick their own mushrooms and the Norwegian safety rules for mushrooms picked in the wild do not apply to Champignons you buy in a supermarket in 99.99999% of all cases. ¹

Note ¹: Unless something went horribly wrong in the food supply chain.