An experiment involving pollution sensors on students has finally turned in its data with some interesting results. What problems does air pollution induce in cities, what did the study reveal, and how does it illustrate the effectiveness of environmental sensors?

What challenges does air pollution cause?

The discovery of coal, the production of iron, and the invention of the steam engine propelled science and technology so dramatically that society itself changed. Those working on farms under feudal systems moved to towns and cities where mass production provided goods for most, not just a few, and developments in science saw the rise of trains, planes, and electronic messaging.

However, this rapid development also saw a sudden increase in CO2 production, destruction of habitats, and the introduction of compounds and chemicals into the environment that have adverse effects lasting for decades. It would take close to a hundred years for world governments to start regulating what chemicals could be used in products, what particulates can be emitted into the atmosphere, and what levels of exposure to harmful compounds are acceptable to both people and the environment.

Air pollution has steadily improved over the years thanks to the introduction of regulation, catalytic converters in vehicles, and scrubbers in chimney stacks. However, vehicle usage has only increased, and the rising emission levels combined with long traffic queues result in poor air quality in cities and towns.

The most significant danger of air pollution is reducing life expectancy caused by lung-related diseases like cancer, asthma, and chronic heart conditions. Despite the massive improvements in air quality, it is still estimated that the number of deaths in the UK caused by air pollution range from 28,000 to 36,000. According to the UK Government, reducing the number of air particulates (i.e., dust) by 1µg/m3 could help save 50,000 cases of heart disease, 16,500 cases of strokes, and 9,300 cases of asthma.

London project shows car usage and air pollution link

In 2018, a project was launched in London to assess the impact on school children and the ambient air pollution they are exposed to throughout their days. Students were fitted with pollution sensors that would monitor levels of air particulates throughout their day. This data would be then sent to a database for researchers to later analyses. The sensors used by researchers detected nitrogen dioxide (a common pollutant caused by diesel vehicles) and 2.5PM particulates (i.e., particles less than 2.5µm in size).

The data from all of the sensors have revealed a strong link between air pollution and school transportation mode in 2021. Students who walked or cycled to school were exposed to significantly less pollution than those who went by car. Furthermore, the revelation of this data to students saw 31% of parents change from using a car to walking, demonstrating how data can help provide parents with informed decisions.

How can wearable sensors help to monitor pollution in the future?

The project run by researchers in London to track air particulates and the amount of exposure students are exposed to demonstrates the genuine potential that wearable sensors have. The ability to monitor current atmospheric composition can help users make more informed choices as to what transport they take, the route, and their destination based on the impact on their health.

However, future sensors could be improved by integrating them into commonly used devices such as smartphones and smartwatches. Then large-scale networks (such as cellular data) could be used to interconnect these sensors to public databases. This would turn citizens into mobile IoT platforms that can monitor the environment and provide researchers with valuable data.

Pollution patterns might be connected to factors like the time of day, month, vehicle usage, and even personality characteristics. Such data may assist government agencies in drafting more effective pollution-reduction legislation that targets the underlying causes of pollution rather than blanket bans that can frequently cause damage (such as the effect on businesses).

Of course, there is also the privacy concern that wearable sensors streaming environmental data would also have to stream their location. Data gathered by a sensor combined with GPS would essentially be a tracker that, if in the wrong hands, could be used to see behavioural patterns of users. As such, any system would have to either autonomise the data, scramble user IDs, and ensure that there is no way for a specific sensor to be related to any individual user.