[Reily]

Dogfish have mildly toxic spines I think in their dorsal fins. Is that easy to remove and does it do anything to the meat if not done properly?

[beelzepug]

Dogfish urinate through their skin. Tasty, no? If you have some, eat it right away. In a couple of days you won’t be able to stand the smell.
Oh, and have you ever eaten surimi? It’s a pasty substitute for crabmeat using various kinds of scrap fish. We have a place that makes it here in my town, where we have plenty of Dungeness crab, some of the finest crab there is. No excuse for eating garbage when the real stuff is available.

[Bloody Sam Roberts]

I've never cleaned one and get them fileted from Patriot. However, as they told me, you must soak them in a solution of ascorbic acid before cooking. Whether that is diluted lemon or lime juice or some other form of ascorbic acid. It draws out the low levels of formaldehyde and urea that naturally build up in the fish and can ruin the flavor. Though it could be related to the spine/dorsal fins as you say.

Not a huge deal. A 5 gallon bucket with fresh water and 1/4 cup of lime juice for 3 or 4 hours does the trick.

[JimRed]

Dogfish have mildly toxic spines I think in their dorsal fins.

Spiny dogfish do, smooth dogfish do not.