The key statement on your source is "Individual solvents may cause one or more of these."
There are some solvents that are really dangerous. My comment is just that methyl ethyl ketone isn't one of them. It's very similar to acetone, which your body creates by itself when it breaks down fats.
Now that's not to say you shouldn't try to limit exposure (you'd be stupid not to), but in the grand scheme of solvent toxicity, MEK is one of the safer ones.
There are some solvents that are really dangerous. My comment is just that methyl ethyl ketone isn't one of them. It's very similar to acetone, which your body creates by itself when it breaks down fats.
Now that's not to say you shouldn't try to limit exposure (you'd be stupid not to), but in the grand scheme of solvent toxicity, MEK is one of the safer ones.