Hi Gents –
Hard to say from the photo, but I tend to agree with Michael and Robert that the material on the side is visually consistent with efflorescence; don’t know about the stuff on the bottom.
But, I once was involved in a case wherein a “certified mould inspector” declared some efflorescence was “toxic mould” and “ordered” the occupants of an old folk’s home to immediately evacuate the property or they would die.
I was called in.
The property manager was incredulous when, without collecting a sample, I declared the material wasn’t mould, but was harmless efflorescence.
“How can you be so sure, without collecting a sample?!” He cried …
So I scraped off the material and threw it in a cup of water where it promptly dissolved. I explained that mould doesn’t dissolve in water, but efflorescence, being just salt crystals does dissolve.
Then he complained “How can I be sure that it’s harmless?” So, I drank the water.
Ta da! Science at its best (burp).
Caoimhín P. Connell
Forensic Industrial Hygienist
The opinions expressed here are exclusively my personal opinions and do not necessarily reflect my professional opinion, opinion of my employer, agency, peers, or professional affiliates. The above post is for information only and does not reflect professional advice and is not intended to supercede the professional advice of others.