The Future Of

Air Quality

Episode Summary

Everyday, we breathe in more hazardous chemicals and gases at home, work and in the environment than you think.

Episode Notes

Episode Transcription

[00:00] This is The Future Of, where experts share their vision of the future and how their work is helping shape it for the better.

Amelia Searson:

I'm Amelia Searson.

Jessica Morrison:

I'm Jessica Morrison. Today we're discussing the future of air quality. You may have heard how coal miners used canaries for detecting toxic gas in underground mines. And we're all familiar with smoke detectors, particularly their relationship with burnt toast! But in all seriousness, poor air quality in our everyday environment is more common than you might think. From hazardous chemicals and household cleaners to sulfur emissions from nearby industry, exposure to such toxins can impact our health.

Jessica Morrison:

Today we're exploring how cutting edge research in electrochemistry could drive innovation in this area, detect hazardous gases sooner, and reduce our risk of exposure. With us today is Associate Professor Debbie Silvester-Dean a researcher in Curtin's School of Molecular and Life Sciences. Thank you for coming in today, Debbie.

Debbie Silvester-Dean:

Thanks for having me.

Jessica Morrison:

Now just to get started, what is air quality?

Debbie Silvester-Dean:

Air quality is a measure of how clean or polluted the air is. So we probably learned in high school that the air is made up of gas, and most of this gas is nitrogen. There's about 21% of oxygen, which we need for breathing, and the other, roughly 1% of gases include things like carbon dioxide, ozone, and some other more hazardous gases. And when we breathe in polluted air, these gases or particles can enter deep into our lungs and they can make us quite sick. This could happen over a long period of time if we're exposed to really polluted environments, and can lead to chronic health conditions. So it's really important for us to have good air quality.

Amelia Searson:

[02:08] It's interesting. When I think about air quality and maybe bad air quality, I think of a dystopian landscape with an oil spill, post-nuclear-holocaust sort of thing. But as you say, it's more common than we think. So how common are hazardous gases in our households, suburbs and workplaces?

Debbie Silvester-Dean:

We're quite lucky in Australia that we've got quite clean air. We very rarely see poor air quality, even in our major cities. But sometimes, especially if we have things like bushfires, this can make the air quality hazardous. And so we're encouraged to remain inside. It's actually the air quality inside our homes that's more of a concern. Poor indoor air quality can cause headaches, fatigue, and can aggravate conditions like asthma or allergies. And poor air quality can come from things like cleaning products, from air fresheners, and a lot of people don't realise, but things like furniture, especially wood furniture, can expel gases when they're new. Carpets, as well – the adhesive on the carpets and the underlay can outgas. Other things which are important inside are things like wood heaters. And if we're renovating our houses, there might be things like when we remove the paint from the wall, we can get hazards into the air.

Debbie Silvester-Dean:

In terms of outside of the home, diesel engines are probably the most important contributors to air quality and not just engines and cars, but also outdoor power equipment. So this may be in the mining sector, or even people who are doing gardening. The diesel fumes can be released from these equipment and they can build up in areas above where the machines are. We should always be wary of all fumes that we can smell. And if you smell a fume, you should think to get some ventilation going. There's more chances of exposure to hazardous gases in our workplaces, especially if we work in confined spaces without good ventilation. And this could be industries such as painting, fumigation, fuel filling stations, even the refrigeration industries and particular, the mining industry, which is obviously important in Western Australia. So we're actually at risk of lots of toxic gases, more than we realise.

Amelia Searson:

I just bought an aroma diffuser. I've definitely noticed when I have it on in my room, I get headaches. So maybe I'll turn it off.

Debbie Silvester-Dean:

Yeah. So those sort of things, if you're going to use them for a short time, that's fine. But then ventilate the room – make sure you open the window. If you're breathing it in overnight, then that's 12 hours of exposure.

Jessica Morrison:

[05:01] Just the list you rattled off then, I could think of at least five that we're doing at our house alone, so I'll be having a chat with my husband after this episode! What are the current technologies for assessing air quality in our homes and in our suburbs?

Debbie Silvester-Dean:

I did a quick search and there's about eight to 10 monitoring stations around the Perth and Peel region. These provide hourly or eight-hourly measurements of different pollutants. They include things like carbon monoxide, nitrogen dioxide, sulfur dioxide, ozone, and you may have heard of these particles: PM10 and PM2.5. These are particles that have diameters less than 10 microns or less than two-and-a-half microns. So there's these monitoring stations around, which is great. That gives us an indication of the general air quality. But as I said, there's so many different things that can cause hazardous air. It's not really localised. So we don't really know in our local area how the air quality is. And in terms of homes, there's actually not many sensors in our homes. You mentioned at the beginning the smoke alarm, but what other sensors do we have for gases?

Debbie Silvester-Dean:

You can buy carbon monoxide detectors. My aunt and uncle in the UK have got one, because, especially in the UK, they have the gas boilers inside the house most of the time. So you have to be careful if there's carbon monoxide being expelled from the gas boilers. In Australia, we have a lot of these outside, so it's not so much of a problem. But generally inside our houses there's not many sensors for these type of toxic substances.

Jessica Morrison:

[06:37] Debbie, how is your research going to lead innovation in this area?

Debbie Silvester-Dean:

I'm working on new types of materials for electrochemical sensors. There's already electrochemical sensors available on the market. Particularly in industry, you can buy a sensor for a couple of hundred dollars. And if you work in the mining sector, you may give these to all your employees to monitor the gases that they might be exposed to.

Debbie Silvester-Dean:

But these type of sensors have some limitations in that inside the sensor, they have a liquid, which can evaporate in very hot and dry conditions. And so, in a Western Australian mine, this might mean that the sensor dries up and doesn't work well anymore. Another challenge with the design is it's very hard to miniaturise. We need to miniaturise, especially because the materials that we use for the electrodes in these sensors are made of platinum – very expensive, scarce materials, so we don't want to have to use a lot of them. My research is focused on trying to miniaturise these sensors, make us use much less amounts of these expensive materials, and to overcome the liquid problem.

Debbie Silvester-Dean:

I'm working with a new type of materials called room temperature ionic liquids. They're like salts, like a table salt. Sodium chloride is the table salt you'll put on your chips.; we're working with a liquid version of these salts. The chemistry is changed so that they are liquid at room temperature, and these liquid salts are much better than normal solvents because they don't evaporate. So we can use really tiny quantities of them and we don't have to worry about the sensor drying up.

Debbie Silvester-Dean:

Another innovation we are working on at the moment is to make these really robust. If we have these tiny devices with a small drop of a liquid, it's a problem if the liquid rolls off the sensor. So we're trying to make it more like a solid state type of electrode. We can do this by mixing these ionic liquids with polymers, to create these gel type materials. And we change the chemistry inside the gel to selectively absorb certain gases so that we can detect them.

Jessica Morrison:

When you talk about miniaturising it, these will be able to be used widely because they're not so cumbersome from what you're talking about with the current devices on the market?

Debbie Silvester-Dean:

Exactly. The technology for miniaturised devices is already available. If you know anybody that's got diabetes, they have a disposable strip sensor that they use to monitor the glucose concentration. The technology that's used in the glucose monitoring sensors is very similar to what I'm using for the gases. But with the glucose sensor, there's an enzyme that's used in the materials that's really specific towards the glucose. So it's a very, very good sensor.

Debbie Silvester-Dean:

The challenge with the gases is it's very hard to get something that's selective because these gases are really small molecules. So we need to design the chemistry and understand the chemistry to make the sensors be widely available for people to use. I think that we can eventually end up putting these sensors into our mobile phones, and using the batteries inside our phones to drive the sensing reaction, but we still need to work more on the chemistry of the materials first for air quality monitoring.

Jessica Morrison:

What other applications does this work have, Debbie?

Debbie Silvester-Dean:

In general, I'm mostly focused on sensing. In addition to gas sensing, we're also looking at explosives detection. This could be for forensic applications where we're swabbing clothing of suspects and detecting explosive residues. It could also be for groundwater monitoring – so if there's contamination in groundwater, we could detect explosive residues there around mine sites. We're also looking at things which are contaminants in water, such as parabens from sun-creams, which can build up in water and can affect the marine life around. So our sensors have lots of different applications.

Debbie Silvester-Dean:

We can also use the fundamental knowledge from our sensor work, and this can go into other devices such as batteries, capacitors and fuel cells. Ionic liquids are already being used in these type of applications. And especially for oxygen sensing, the oxygen reduction reaction is really important in metal-air batteries and also for fuel cells. So, what we're understanding in our gas sensing work is really helping to go towards fundamental understanding in other areas of electrochemistry.

Amelia Searson:

That's incredible. Because obviously humans are inherently beings that have to consume oxygen, as you say, marine life, and the environment in general. And you touched on it before Debbie, about mobile phones being portable pollution sensors, and smartwatches, even. Could you tell us a bit more about that?

Debbie Silvester-Dean:

I think it's going to be possible in the future for us to have these strip type devices that we can plug directly into our phones and maybe smartwatches as well. They'll probably have to be a separate device to our actual phone, because you have to have the chemistry and the materials of the electrodes in there. But I can see that if people can work together –the engineers, the chemists and the physicists – .to get the right materials to go in this type of sensor, then I think it should be able to be available cheaply and worldwide to monitor air quality

Debbie Silvester-Dean:

As I mentioned at the beginning, we're quite lucky in Australia that, at least outside, we have good air quality. But this could be really useful in countries like China, India, Thailand, where the air quality can be quite poor. So people would have the ability themselves to know whether the air is good enough for them to go out for a run.

Amelia Searson:

Is there sort of a timeline for when this sort of technology is expected to become available?

Debbie Silvester-Dean:

The sensors I'm talking about are already available, but to make them available to the everyday person, I think is going to take maybe five or 10 years, depending on how the material development goes. It's hard to know right now, but I think it's definitely possible.

Jessica Morrison:

[13:30] Just going off topic slightly, but still within the realm: Women in STEM. How did you become interested in studying this and doing such extensive work in this field?

Debbie Silvester-Dean:

When I was a kid, I was always really interested in maths. I loved playing with numbers and I would always be sitting down doing calculations. No one in my family was an academic, they'd never been to university. So I just went with what I enjoyed. And I was naturally attracted to the maths and the physical sciences. I always wanted to know why is this happening? and try to understand the world. So when I did my A-Levels in the UK, I did maths, chemistry and physics, always thinking that I love maths, I was the best at maths, and I would go on to do a maths degree and maybe become an accountant.

Debbie Silvester-Dean:

But I did some work experience in an accountancy firm during my A-Levels, and I sat and I looked at everyone and I thought, "Oh, I don't know, it's a bit boring". You have to sit in front of the computer and type in numbers all day, and there was part of me thinking I want to do something that's more hands-on. I had a really good chemistry teacher in my A-Levels who encouraged me to do chemistry because I could do this hands-on thing, which I craved, and also use my maths skills to solve problems. So chemistry for me was the perfect fit for what I wanted to do. And then I just continued, and that's where I am now.

Jessica Morrison:

How important is it for more females to get into STEM? It's a commonly talked-about issue.

Speaker 3:

In chemistry and especially in physics and engineering, there's very few females in senior positions, compared with males. So it is really important to encourage people to start to fill those higher positions as well. Because women make up half of the population, so if we exclude them from the science and technology development of the future, then we're excluding half of the ideas and half of the voices. And diversity is the key to progress in the future – so we really do need to encourage girls and women into science and engineering careers in order to make the leaps forward that we need for the future.

Jessica Morrison:

Summed up perfectly. That's all we have time for today. Thank you so much for joining us, Debbie. Where can people connect with you?

Debbie Silvester-Dean:

You can connect with me on LinkedIn, Debbie Silvester, and also on Twitter. My handle is @debbiesilvester. I also have a WordPress page, which has got all details of my research and you can find that at debbiesilvester.wordpress.com. And finally, you can also send me an email. I'd be happy to take any questions.

Amelia Searson:

Debbie, are there any ways that people can get involved in your research, maybe like undergraduate chemistry students?

Debbie Silvester-Dean:

We’re always looking for undergraduate students coming through and getting some experience with the research. You can also do it in high school. We've had a few year 12 students do a couple of hours of work experience with different academic researchers in our department. And so that's a good idea. You can contact the head of chemistry to try to get some students involved. We'd be happy to give people a taste of the research that we do.

Jessica Morrison:

Awesome. Thank you again, Debbie, for coming in and sharing your knowledge on this topic, we've had a great time listening.

Debbie Silvester-Dean:

Thanks for having me.

Amelia Searson:

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