Atchoo! Allergy season ahead

Protect lungs from grain dust | Farmers can develop allergies, asthma, infections and more

Farmers may be harvesting more than they bargained for this fall.

The grain dust they inhale into their lungs contains grain particles, moulds, insects, mites, fungi and other organic material that can cause minor irritation to debilitating lifetime lung diseases.

Niels Koehncke, associate professor of occupational medicine with the Canadian Centre for Health and Safety in Agriculture, said it’s difficult to pinpoint what’s at the root of the health problems.

“There’s a lot we still don’t quite understand about grain dust allergy and grain dust irritation,” he said.

What is known is that breathing grain dust can cause short-term respiratory problems such as coughing, shortness of breath and irritation of the nose and throat or can lead to long-term ailments such as allergies, asthma, chronic obstructive pulmonary disease or farmer’s lung.

Koehncke said farmers can protect themselves by adopting a few simple practices.

The first is avoidance. While it’s not always possible to reduce exposure to dust at harvest, there are times when farmers can position themselves so that they’re out of the path of the dust.

“If you’re doing some shoveling or moving grain, then you can stay up wind,” he said.

“Those sorts of simple things, just to keep yourself out of the dust cloud.”

The most practical solution is to wear a proper dust mask during times of high exposure. Farmers should use masks with a minimum N95 filtration efficiency rating.

Koehncke said they don’t need the black Darth Vader type masks. A white, two-strap paper mask available at most retailers will suffice as long as it has the N95 rating. The letter N isn’t as important as the number 95. A different letter means it filters out other material besides dust.

He acknowledged that many producers don’t like wearing masks when it’s hot out and they’re exerting themselves, but that’s exactly when they should be wearing them because they are breathing more deeply and frequently.

“Compliance is sometimes very poor just because it’s not comfortable,” said Koehncke.

The masks don’t have to be worn all the time, just during periods of high exposure to dust.

The CCHSA has produced a video about respiratory hazards on the farm that can be found at

In the video, Shelly Kirychuk, assistant professor with the CCHSA, says the health effects of grain dust are influenced by the type of harvest activity, method of grain storage and type of grain with which the farmer is working.

“Barley dust, as most farmers know, or canary dust is much harsher on your respiratory system than other grain dust,” she said.

“It has little bars on it or little tentacles that kind of scratch on the way down. Anyone who has worked with them knows that those are the itchier dusts versus the softer dusts of wheat and canola.”

Large dust particles tend to settle out in nose hairs or get caught in the upper respiratory system.

“You’ll cough and sneeze those out. The smaller dust goes deeper,” said Kirychuk.

That’s why growers need to ensure they use a mask with a minimum N95 rating, which filters out the small dust particles.

Farmers need to be extra cautious when moving grain or hay that has sat for a while and may contain mould spores.

Inhaling them can lead to organic dust toxic syndrome, a short-term illness characterized by coughing, fever, chills, laboured breathing and muscle pain, but it can also lead to farmer’s lung, which is a lasting condition characterized by difficulty breathing and reduced lung capacity.

Koehncke said farmer’s lung can happen quickly or can develop over prolonged exposure to certain moulds.

Growers who have pre-existing lung conditions such as asthma have to be especially cautious during harvest because the dust can trigger their symptoms.

Parents should ensure that children with allergies take their medications and use their inhalers as prescribed by their doctors, said Jaimie Peters, health initiatives co-ordinator with the Lung Association of Saskatchewan.

“Sometimes what happens in summer is kids are feeling good or they forget or they’re on holidays and they’re not taking their medications as regularly, so they’re not as prepared when they get hit by their triggers in the fall,” she said.

Fall is a peak allergy season with plenty of moulds, pollens and grain dust in the air. It is also a time of stress for children heading back to school, and there will be increased exposure to the viruses that tend to circulate when large groups of children gather.

When those factors are combined, they can cause problems for children with respiratory illness. Peters said Sept. 17 is the day with the most asthma-related emergencies.

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