Hi Maud - Health & Safety? - I really doubt if such a thing exists here. H&S is an alien concept in Spain - you just need to look at the way they build the roads with no ear protection when they are drilling, they have bulldozers working inches from the public, etc etc. I even watched a fabulous jousting show at the Medieval Market in Orihuela where the horses were charging up and down the main road, again just inches from the crowd with just a flimsy little barrier in between - exciting but very dangerous!
You could take a note of the names of the chemicals off the bottles (that is if it is in the original bottle) and look it up on the internet and you could also approach the local town hall and ask if there are regulations about such chemicals.
However, even if you find that the chemicals are dangerous, I doubt if the authorities would care. In my opinion, your best bet would be to get the President to stipulate what chemicals you want used on your community - you are paying for them anyway so you can tell the gardener exactly what you want.
Good luck!!