A further advantage is that the presence of many chemical agents would not be detectable until they had done their fatal work, because so often they are colourless and odourless.
These particles are tasteless, odourless and invisible.
They are almost odourless, are difficult to detect chemically, and are very stable.
Fluoride is completely odourless, tasteless, harmless and essentially undetectable, except by monitoring machinery or, indeed, by the beneficial effects it has on teeth.
We know that carbon monoxide is odourless and colourless, so it cannot be seen.
Some of these substances are odourless, and it would take time to detect some others.
I think it is a fairly odourless amendment.
Pure methane gas may be colourless, and odourless.
