Alex said:
Maybe also get a background in biology then. Or medicine.
...
The first thing one learns in any field where you handle raw chemicals in a lab is to not trust your smell. You do this before you even get foot in a (real) lab. This is not only Chemistry but Also Medicine and Biology.
Actually, over here one of the first year exams for a Chemistry degree is Cellular Biology. To make sure the students understand the ways a chemical can affect living tissue. The material of that course is never used in further curricula, but gives the awareness one needs even if specializing in inorganics field later.
The second thing you learn - if keeping tabs - that a lot of the freely available/used home use or light-commercial use chemicals are actually pretty crappy and toxic. Mostly in the "it will kill you slowly" way.
Care to explain how IRRITATING is good for you?
It tells me in no unclear terms that the chemical I work with has reached a higher-than-nominal concentration, allowing me to take preventive actions to reduce the inhalation exposure before it is too late. All this reliably, intuitively and without any special equipment on hand needed or a need for training.
Ok, you might not drop dead right away, but irritation is your body giving you a warning. That's not something you brush over.
I think where we differ is I am discussing alternatives of:
A) it may (slowly) kill you but will not really bother your (or even know) it being around (see e.g. Toluene)
B) it may (slowly) kill you but is an irritant hence you will know about it and can adjust/reduce your exposure before it is too late (e.g. acetone, which is not toxic in quantities which are not irritating)
Hence my preference of acetone for use -especially- by non-chemists compared to the other organic solvents commonly in use which are more toxic but are also LESS irritating.
You are correct in a way too.
For a Chemistry major, knows his chemicals, has a measuring kit where required and who takes all the precautions either way, an irritating agent is an annoyance.
But there are only so many qualified Chemical (Biology, Medicine/Pharmacy..) majors out there.
Most of the people have to live with at best with a High-School chemistry knowledge.
I am old enough to know you will not recommend an MBA to "keep his exposure to a maximum of 10 minutes/day of breathing air with 1000 ppm of the compound in question." heck, I would not be stupid enough to tell that to a Chemistry major student!
No, I would simply forbid to use the compound except with a ventilated chamber simply because I will know it would not be realistic to expect the people to be able or want to /in case of a student/ abide by the maximum exposure rules themselves.
On the other hand,
if the compound is know to be toxic in high concentrations BUT is an irritant already while in low concentrations known to be safe (think ammonia solution, or mentioned acetone) then I can safely let the people use it as the exposure is self-regulating.
In case of secondary risks, I may simply add an instruction to not wash hands in it.
And you are correct smell is an excellent detector if something is -affecting- your nose cells in the natural setting. Industrial solvents are no natural thing, though.
EDIT:
If it irritates you, it means there is a part of your body that does not like it.
My grandmother used to irritate me and I did not like it. Yet I miss her sorely.
The group of chemicals your body does not like and those which are toxic to it are two distinct groups. There is an overlap, but not a very big one actually.
As it goes, acetone is very low on the list of irritating chemicals.
The topic was about smell/odor, so meant irritating in that context.
Try breathing a concentrated acetone vapor ... then try the same with e.g. Toluene (orders of magnitude worse for your body).
Real story:
There were stupid kids in our yard who /in the absence of better drugs/ actually inhaled Toluene to get high. They would never manage to do that with Acetone ... But even if did, would have a bit more brain cells survive in them to adulthood.
below line:
If people wash their bare hands in /any/ non-natural chemical that is not a designated hand-wash agent that is a completely different level of stupidity. And almost criminal negligence of the people who instructed them that it is safe to do so...
