Yes, I have experienced this when metal toxic. I have had it when eliminating amalgam toxins (metals/mercury), plus after smoking a load of cigarettes (other chemicals and metals).

So everytime I sweat with either of these issues, I can smell metals and taste them too sometimes.

You may also sweat more via the hands and clammy hands can be another sign of toxicity too (and other issues). Though i realise they have easier access to your nose.

I remember onetime when my body was dumping metals, I exercised on my treadmill and sweated quite a bit. Well I was late for a doctor's appointment and didn't have time to shower and raced to get there. Well the doctor was quite overwhelmed by the smell of metal as I walked in....I could also smell it but was quite used to it.

If you can sweat and handle some heat, take hot baths with epsom salts or sea salt and baking soda. (a cup each), as these aid elimination of toxins/metals via pores. They are really helpful, but only if your body is strong enough to actually handle heat and sweat.

I cannot really do this these days since infections took over, so now my system is pretty stuffed. But it used to work REALLY well and sometimes to well because the detox symptoms could be too strong sometimes.

Saunas are also good. Exercise is brilliant, but only if it is nothing that is going to strain you. Rather a good walk (treadmill or outdoors) and/or some gentle rebounding too are brilliant.

These all help, plus antioxidants support supplements too and the diet.

The smells of metal can be mercury and other metals. Any heavy metals I'd say.