I'm looking at moving to Altona but am worried about the extent of industry in the local area...

Gotta love these city types expounding their views. The smell at the beach in Altona is seaweed, as the area is renowned for seagrasses vital for the health of the bay. The water treatments are miles away and the quality at the end of the treatment is very good. Yes, there is industry to the north of Altona, but once past the refineries you reach Cherry Lake and the landscape alters dramatically. After that it is an attractive suburb which is rapidly gentrifying, as older houses come down and new homes, units and apartments are built. This suburb is still relatively affordable but prices are definitely on the rise.

I'd steer away from Altona if I were you. Beach air there has a strange smell that I have not smelled at other beaches I have been to. I have lived in Sydney and Geelong. I visited the area a while ago as I need to move to Melbourne for work. I didn't like the smell of the sea in Altona. Maybe it is due to the water treatment plant they have there or maybe it was just that particular day. But I'd still recommend avoiding the area.

Depends where you buy. If you are close to the beach the on shore winds give you clean air most of the time. Don't want the soil contamination facility here if it can be avoided. Needs to be out of the urban areas in my view. But the populations most affected would be those on the northern side of the facility, due to prevailing winds from the sea (i.e. south/ southwester lies).