Ascan through a list of the world’s most dangerous timbers in terms of potential harmful wood dust effects is enough to get even the most lax woodworker reaching for his safety mask.

Skin blistering, cardiac problems, asthma, vomiting, blindness and even death in the most extreme cases could potentially occur with some of the most toxic species.

Admittedly, your average joiner is not likely to be cutting a piece of mulga (acacia aneura), an Australian hardwood which is suitably matched with a skull and crossbones symbol on The Wood Database’s list of toxic woods. This wood is poisonous and has been used for spear heads by aborginals.

Poison walnut (sap is corrosive), tambootie (diarrhoea and blindness) and sneezewood (violent sneezing) produce similarly dramatic potential health impacts.

Wood dust toxicity generally causes either irritation, sensitisation or poisoning.

Commercial species
While breathing in any of kind of wood dust is harmful and needs to be guarded against, there are some commercial species available in western Europe that are worth highlighting for their particular toxicity.

Western red cedar is one of these woods which gets the four-star treatment on The Wood Database for its toxicity. As well as being a skin irritant, this dust can cause asthma, nervous system effects and (rarely) cancer in the nasopharynx – the upper region of the throat behind the nose.

Rosewood, wenge (nervous system effects) and teak (hypersensitivity pneumonitis, nausea and conjunctivitis) are others noted for their ability to produce more serious harmful effects.

But even the more common black walnut and oak have their problems – they are both sensitisers, meaning the more you are exposed to their wood dust the more severe and adverse health reactions can be.

But yew, which is sawn by several mills in the UK and used by furniture and cabinet makers to produce highly-prized items, is potentially the most serious and gets a skull and crossbones symbol on the database. Yew contains a direct toxin which could threaten life, as well as being an irritant and causing nausea.

West Sussex sawmiller English Woodlands Timber saws yew logs and sells the timber to a variety of clients.

The combination of the wet nature of the timber, the fact that the company is only doing the primary milling process (on a bandsaw) and health and safety measures taken means there is little risk to its workers.

Advice to customers
"It’s one of those timbers that we do pay attention to," said English Woodlands’ Sarah Farmer. "We tell customers not to make anything out of it relating to food."

The company does tend to steer clear of machining toxic tropical timbers, including iroko.

West Sussex sawmiller WL West & Sons saws yew and a variety of exotic timber species. On its online list of exotic and Australian timbers, the company uses a big warning symbol and cautions that many of the woods could cause respiratory and irritant problems and that suitable mask, eye and glove protection must be worn. And it has a seminar room where it gives presentations to woodturner customers, including advice on the health risk of some species.

"The industry knows that when you’re dealing with fine particulates you should wear a dust mask," said joint managing director David West. "But a fair proportion of customers do not understand the toxicity of each species. We know yew is the obvious one. From the retail side of things, when we are talking to woodturners we tell them to make sure that they have a good quality P2 mask."

Spruce, possibly the most sawn species in the UK, is on safer ground on just one star, although it is an irritant and a sensitiser. Pine is slightly more toxic at two stars – irritant, runny nose, asthma.