Keeping our lungs healthy: air pollution, urbanisation and smoking

Urbanisation is the process by which more and more people leave the countryside to live in cities. Urbanisation impacts health and disease, for example asthma is more prevalent in urban areas than in rural areas. This may be due to lifestyle in urban areas as more people tend to smoke, or they do not regularly exercise.  Or it could be linked to the air quality in both homes and outdoors.  

A key session from the ERS Congress scientific programme looked at how future city life around the world may have the potential to improve lung health, with innovative strategies for change.  

Impact of outdoor exposures  

Green spaces have lots of benefits for health. Cities generally have higher temperatures than rural areas, this is known as the ‘urban heat island effect’. 

How can we tackle climate change? 

We can tackle climate change by using adaptation techniques, such as flood protection, and mitigation techniques, such as renewable energy. Adaptation techniques aim to reduce the impact of climate change on the environment, whilst mitigation techniques aim to prevent the worsening of climate change.

A tree restoration project in Colombia saw a 2°C temperature reduction in the first three years of the project. Another study in Paris found that many of the deaths that occur due to urban heat can be avoided with increased tree coverage. In addition, forests within cities (‘urban forests’) can improve air quality by reducing airborne pathogens (for example: bacteria, virus, or fungus that can cause disease), however reduction in greenhouse gas emissions are still necessary to tackle climate change. 

What is pollen forecasting? 

Pollen forecasting is the prediction of pollen count. It can improve the health of people who are susceptible to a pollen allergy by alerting when there are high pollen counts and preventing worsening of the person’s condition. The speaker mentioned that there was a technological revolution is underway, promising significant advancements in this area. 

Impact of indoor exposures  

Key factors that influence the indoor environment include: 

• Geographical location 
• Outdoor surroundings (for example: cities or countryside)
• Occupants (for example: the people who live there, pets or plants) 
• Building design (including the materials used, ventilation, humidity and how often it is cleaned)

Lower temperatures are associated with reduced allergens. Levels of allergens indoors may be increased because of old mattresses, poor ventilation, and dampness. 

The ‘hygiene hypothesis’ indicates that exposure to a diverse microbiome (the community of microorganisms within a specific area) early in life is beneficial for training the immune system. More ‘beneficial’ bacteria are found in farmer’s homes than in the city. 

How do building design and material affect the indoor environment? 

Materials that retain moisture (including wood and carpets) may increase the growth of microorganisms. However, synthetic surfaces and antimicrobial coated surfaces may prevent the growth.  

A good ventilation system is key to reducing growth of microorganisms. Yet, although ventilation systems are very useful for controlling temperature and humidity it can be a challenge to get the balance right as systems that are too tightly sealed may trap pollutants and moisture.  

What public health policies could help to tackle climate change regarding the indoor environment? 

• Climate resilient buildings: Buildings that can withstand extreme weather events and changes in temperature and amount of rain. 
• Regulations and standards: Implementing stricter air quality standards and regulations for both outdoor and indoor environments. 
• Public awareness campaigns: Educating the public about the importance of air quality and the indoor environment (where we spend 90% of our time) and how to improve it in homes and workplaces. 

Key takeaways surrounding urbanisation and air pollution 

• Urbanisation can have an impact on our health due to many factors including increased temperatures, higher probability of smoking, and higher chance of not getting enough exercise.  
• Techniques, such as increasing tree coverage, can help improve air quality and reduce temperatures and so improve health especially for people with lung conditions. 
• Pollen forecast can also help prevent exacerbations in people with lung-related conditions as the alerts can let people know when pollen counts are high, and people may be at risk. 
• Having a high-quality ventilation system as well as surfaces that do not retain moistures can improve air quality within a house.  

One of the main ways we can keep our lungs healthy is avoiding the harm from smoking and second-hand smoke. In one session at the ERS Congress, experts debated the concept of a smoke-free generation.  A smoke-free generation would include stricter laws on tobacco sales and increased encouragement to get current smokers to quit. The focus is on educating the younger generation on the health risks of smoking and reducing the numbers of people who smoke. 

A failure to implement tobacco control leads to: 

• Deaths of 7.7 million per year worldwide. 
• Accounts for 1 in 5 male deaths.
• 2 out of 3 people that smoke will die to a smoking-related disease.  

How can a smoke-free reality be achieved? 

The World Health Organisation has a strategy to promote tobacco control (MPOWER): 

• Monitor tobacco use and prevention policies 
• Protect people from tobacco smoke 
• Offer help to quit tobacco use 
• Warn about the dangers of tobacco 
• Enforce bans on tobacco advertising, promotion, and sponsorship 
• Raise taxes on tobacco

Evidence suggests that the more these strategies are implemented, the more effective tobacco and smoking control will be.

In the UK, tobacco companies make profits of around 50% whereas profits for general products, like food and household goods, is around 12-20%. The talk called out how this was unacceptable. Capping these profits could instead pay for tobacco control plans. 

A priority is to get current smokers to quit smoking. It is also important to stop people from starting to smoke, in terms of healthcare.

What are the barriers to creating a smoke-free generation? 

The talk called out an urgent need to define smoke-free to clear up the confusion and separate our position from the tobacco industry. For example, whether smoking means banning of classical cigarettes, e-cigarettes, or all tobacco products. 

Barriers to creating a smoke-free generation are that: 

• Nicotine is more likely to cause dependence than cocaine and cannabis. 
• The tobacco industry has spent almost €20 million to influence EU policymakers which has caused delays to smoking-free environments.  
• Thoughts that banning or increasing taxes on tobacco will cause illegal trade.  

However, the World Bank has concluded that tobacco taxes play only a minor role in illegal trade and can be reduced by countries strengthening their tax admin and enforcement. 

How else can smoking be discouraged? 

• Supporting high prices of tobacco products and reducing the availability of these products.
• Worldwide smoke free city initiatives.
• Several countries have banned sale of e-cigarettes. Singapore banned the purchase and possession of e-cigarettes in 2017. 
• The way we design cities can influence lifestyle. Including more areas, such as skateparks, that are engaging to children will prevent them from taking up smoking.

Key takeaways surrounding smoking  

• Evidence suggests that strategies endorsed by the World Health Organization such as helping people to quit smoking and raising taxes on tobacco leads to improved tobacco control and lower rates of people smoking within respective countries. 
• Barriers to a smoke-free generation include the influence that tobacco has on policymakers, lack of clarity on the definition of ‘smoke-free’, and thoughts that impacting access to tobacco products will lead to illegal trade.