The Canadian Centre for Occupational Health and Safety site publishes these careful about Toluene and Xylene, which is also called Methylbenzene or Toluol.
WHMIS classifies Toluene as “very toxic”. Toluene could cause your death if you swallow it. It can damage unborn babies if the pregnant mother breathes toluene fumes.
If you breathe it in a confined area such as a classroom, your throat may start hurting, and it can cause damage to your nervous system too. You may become unconscious from continued exposure, but if you nevertheless have your wits about you, you can speculate the toluene fumes that you have breathed from your dry erase markers if you have some of the following symptoms.
Contact with your eyes or skin can cause damage similar to breathing it, because it soaks by the skin. If you swallow it from markers for kids for example and some enters your lungs it can damage your lungs and suffocate you.
If you work in a noisy ecosystem (such as a classroom) and you breathe toluene fumes, it can increase your industrial deafness.
Emergency action if you can smell toluene or Xylene
Prevent fire by switching off all things that could start a fire. You can’t remove the chance of a static spark, but that can’t be avoided.
If the poison has been breathed, rush the victim to fresh air (for example evacuate the classroom if you smell the marker solvent). If anyone feels unwell, call a poisons centre without delay.
If you get it on your skin (fortunately you can know closest it’s on your skin if it’s the solvent for your white-board markers because of the uncommon skin colour) then wash gently (you don’t want to break blisters) and thoroughly with a soap that is gentle and non-abrasive, in just-warm water, and keep up under a flowing tap that is just warm for a quarter of an hour or more.
If you get it in your eyes, flush them under a lukewarm gently-flowing tap for five minutes while holding the eyelids open with your fingers. If the eyes are nevertheless sore, see a doctor.
If the patient vomits, make the victim lean forward to try and prevent breathing it back into the lungs – which could cause fatal lung damage.
This solvent can also be disguised as Dimethylbenzene, Methyltoluene or Xylol
The WHMIS classification is “very toxic”.
Health dangers are very like those of Toluene, so I won’t repeat them here, but the chances of starting a fire appear to be much worse. Xylene vapour in the air can already be ignited by static electricity, and create an explosion.
Water Health Hazards as a Solvent
seemingly if you drink several gallons of water each and every day you can get “water intoxication”. I didn’t know that it was possible to drink so much water!
Bigger problems are the fluoride and chlorine in drinking water, and already more of a problem are the DBP (Disinfectant By Products) resulting from killing bacteria in your drinking water. DBPs can be a thousand times as toxic as the fluoride in your drinking water.
Fortunately, dry erase markers with water as a solvent use quantities of water that would not be dangerous to drink, and don’t give off toxic fumes. Water vapour is not a fire danger, and only very young children claim that water damages their skin. And some makes of water-soluble inks in markers for kids can be washed from clothing in water without already using detergent.
Warning: You may find markers that say “Toluene Free” or “No Toluene” and they use Xylene instead as the solvent.
The main drawback of water-based markers is that your writing takes a little longer to dry, but that method that “new” markers that you buy are less likely to have dried out in the warehouse before you receive them.