If you must know, it's neutron damage. It's from the reactor wall.

3 seconds sound clip from the Iron Man 2 movie soundboard.

You can hear this line at 00:48:46.584 in the Blu-ray version of the movie.

Quote context

[...]

- You said nobody else would possess this technology for 20 years. Well, guess what? Somebody else had it yesterday. It's not theoretical any more.

- Are you listening to me? Are you okay?

- Let's go.

- Hey, man. Hey, hey! You all right?

- Yeah, I should get to my desk.

- See that cigar box?

- Yeah.

- It's palladium.

- Is that supposed to be smoking?

- If you must know, it's neutron damage. It's from the reactor wall.

- You had this in your body?

- And how about the high-tech crossword puzzle on your neck?

- Road rash. Thank you.

- What are you looking at?

- I'm looking at you.

- You wanna do this whole lone gunslinger act and it's unnecessary. You don't have to do this alone.

- You know, I wish I could believe that. I really do.

[...]