Olá, G'day

I took some shots of our Portuguese neighbour spraying his fruit trees today.
(Glad he didn't spot me doing it, maybe his eyes were stinging)
He has a motorised backpack that blasts out the spray.
I was amazed that he was not wearing a mask.
I've seen others with big spraying units on the back of tractors,
riding through their orchards, spraying away with no masks.
This spray can't be alright to breath in can it? Doesn't it harm the skin in any way?
This:

And this:
