A termite company is proposing spraying Premise foam into the wall around some plumbing, and I am wondering how safe it is. I am somewhat of a worrywart and have concerns about the pesticide somehow contaminating the water lines (e.g. seeping through the joints where one pipe connects to another). I even found the usage instructions for Premise foam which state under "Restrictions": "Do not apply until location of heat pipes, ducts, water and sewer lines, and electrical conduits are known and identified."
That's the gist of my question; but here's all the background in case it helps:
I live on the bottom unit of a two-story condo building that is built on a concrete slab (I guess non-floating, though not sure).
The residents in the unit above mine are experiencing flying termites coming out from a gap between the drywall and the drain pipe under their master bedroom sink. The owner of that unit had an inspection done and it was confirmed that they are subterranean termites. Furthermore, the inspector could not find any evidence of termite activity around the outside of the building; and because the building is on a concrete slab, he believes that the termites are coming from under the slab through a gap or crack where the piping goes through the slab.
Since my unit has the same layout as the one above me, I guess the termite company people assume that the piping goes straight down, and they want to treat the suspected area (where the piping goes through the concrete slab foundation) via my unit, i.e. in the wall behind my master bedroom sink.
They are proposing drilling small holes in the drywall where my sink's plumbing enters the wall and filling the wall with Premise foam. Here are some pictures to get an idea of how large of a space I'm talking about:
The wooden-looking part is the back panel of the cabinetry under the sink counter; the termite people are trying to save me and the HOA the cost and hassle of removing more of that back panel and breaking open a larger part of the wall to confirm exactly where/if the termites are coming from where they think they're coming from. They are (and I quote) "90% sure" that the termites are coming from there.
They're the experts, so who am I to question their intuition; and based on my cursory research online, it definitely seems like a plausible explanation. But I also don't like the idea of taking action without knowing the true source of the problem, especially since it involves pesticides. Furthermore, my wife and I have not seen any termites or evidence of termites in our unit.
So, this is a little off-topic to the original question, but I would also appreciate any expert opinions about whether this proposed work is appropriate to take or if you think the termite company is jumping to conclusions.