Living in East Glasgow in the 40s I can recall that there was mounds of rubbish, mainly of an industrial nature dumped of many areas of open land.
For instance, the former quarries east of Firpark Street in Dennistoun had been end-tipped in the past such that myself and pals regularly excavated decorative clay pipes which presumably were rejects from a clay pipe factor in the distant past.
Between the open section of the Molindinar, and up to the canal, the whole area was composed of tipped rubbish including fused black slag standing about 6 feet high, all of which must have been potentially toxic.
I understand that reports of overcrowding and poor sanitation in the past reported domestic rubbish being stacked as high as the houses before removal. I understand that farmers often removed this, which included 'night soil' for spreading onto fields around Glasgow.
These locations and many others have since been redeveloped, but I suspect that much of this waste has been leveled but is still beneath the ground as another example of Hidden Glasgow.
John