Do not exceed the recommended intake/dosage.

The above warning is on mum's fish oil and on all supplements. The recommended daily intake (RDI) for Seven Seas fish oil for adults & children over 12 is 10ml/day, or 1 capsule/day if in capsules.
1 capsule contains 360mg of EPA+DHA.

Seven Seas fish oil must be dangerous stuff!

Here's some perspective. A small can (213g) of wild Alaskan red salmon contains 14g of fish oil and 1.9g of EPA+DHA. That's 533% the amount you get in one capsule of Seven Seas fish oil. There are no warnings on small cans of wild Alaskan red salmon to not eat more than a fifth of a can a day. I usually eat a whole can at a time. My brain really likes this. See Guess who didn't look after his brain?

For breakfast, I sometimes eat ten Brazil nuts and ten prunes washed down with a milky coffee. Ten Brazil nuts contain ~4,000ug of selenium. That's about 1,000% the RDI for selenium. However, I'm not showing any symptoms of selenium toxicity.

EDIT: I may be showing one symptom. Somebody told me that I smelled slightly of garlic. I had eaten a lot of raw onion on liver pate earlier that day and I was giving off a smell of onion. This has happened before.

Moral of the story: Get nutrients from foods wherever possible.