Sometimes the smell from the “nullah” between the runway promontory and the taxiway was powerful enough to make you retch at the first sniff. I don’t know what it was, but it could turn shiny new brass padlocks a dark purple in colour within a few days. It was also capable of causing problems with gold plated contacts on avionics boxes.
Allegedly, Bob Hope stepped off an aeroplane on his first visit to Kai Tak, took a breath, pulled a face and asked “What IS that smell?” The answer came, “Well, it’s $hit, Bob!” His immediate response was “OK, but in that case, what the hell did they do to it?”