According to the World Health Organization, around 99% of the world's population lives in places where air quality is below guidelines, with over half exposed to harmful pollution. The situation appears to be getting worse, exacerbated by population growth, the continued growth and expansion of megacities, industrialization and climate change.
Globally, the combined effects of outdoor and household air pollution have been linked to some 6.7 million premature deaths annually.
Alongside growing heat stress, air pollution is a major source of respiratory diseases, with outdoor workers particularly vulnerable.
According to the World Economic Forum, poor air quality costs China as much as $900 billion annually in lost productivity and reduced workforce participation due to higher rates of asthma and chronic respiratory diseases. This amount is equivalent to 6.6% of the country's gross domestic product (GDP).
In the US, that figure is $600 billion, or 3% of GDP. Overall, some 1.2 billion workdays are lost globally each year due to air pollution, with forecasts this could reach 3.8 billion days by 2060.1
Natural and human-made sources of poor air quality impacting health
Part of the challenge in addressing air pollution is the fact that it's so widely dispersed and can be created by many different sources.
In urban areas, exhaust smoke from vehicles and industrial emissions remain the primary source of particulate matter (PM). A subset of particulate matter is PM2.5, which is 30 times thinner than human hair and one of the most common air pollutants causing chronic respiratory problems.
Most industry sectors are both a cause and casualty of air pollution. In agriculture, a major emitter of nitrous oxide, methane and carbon dioxide, studies have shown that crop yield and quality can suffer when there's an increase in ground-level ozone.
Travel and tourism, which are often blamed for contributing to air pollution levels via aviation emissions, also are facing challenges. According to the World Bank, for instance, India's tourism sector loses $1.7 billion each year as tourists choose other destinations due to air pollution.
There are also natural causes of air pollution. Each year, wildfires and volcanic activity worldwide release hazardous gasses and particulate matter into the air, adding to the impact from sand and dust storms in desert regions.
Climate change is compounding the threat of smoke particle pollution from wildfires. The growing regularity of heat waves and a phenomenon known as "weather whiplash" feeds into the propensity of fires and adds to the degradation of air quality from such sources.
In the US, there's some concern that wildfire pollution could be reversing some of the Clean Air Act gains amid the growing frequency and severity of fires.2 Currently, air pollution from natural or uncontrollable events is deemed an "exceptional event," meaning it may not be reported in air quality monitoring data.
Canada wildfire smoke dispersed into North American cities
In 2023, Canada witnessed an unprecedented wildfire season. Hundreds of fires exceeded 10,000 hectares (39 square miles), large enough to be considered megafires. The fires were unusually widespread, occurring from British Columbia and Alberta in the west to Quebec and the Atlantic provinces in the east to the Northwest Territories and the Yukon in the north.3
The smoke from the blazes crossed the border into the US and spiked the PM2.5 levels in US cities, including New York and Chicago. Authorities in these cities advised residents to stay at home to avoid prolonged exposure to particulate matter, disrupting daily life and business activities.
Outdoor workers at increased health risk
Poor air quality harms everyone, but among the most vulnerable are those who spend most of their time working outdoors in industries such as agriculture, transportation and construction.
In the face of evolving air quality challenges, the onus is on employers to do more to safeguard the health and safety of their employees from the dangers of air pollution, particularly those who work outdoors.
Infrastructure investment is increasingly important to prioritize workers' safety, including protective equipment, proactive air quality monitoring and tracking air pollution outbreaks as they occur.
Wearable technologies, equipped with sensors that can simultaneously monitor a worker's vital signs and environmental conditions, can help with early detection and prevention. Such tools can help prevent pollution-related impacts and ensure that air quality on-site remains within safe limits.
"There is an increased emphasis on monitoring the health of the outdoor workers," says Ania Caruso, Casualty Practice leader at Gallagher. "That includes regular healthcare checkups, monitoring air quality, and providing information associated with the health risks associated with heat and poor air quality."
The US Clean Air Act: Now and Then
In the US, the Clean Air Act of 1970 is one of the country's foundational environmental laws, which has had far-reaching impacts across industries for decades.4 Enacted by President Richard M. Nixon at the height of the country's urban air pollution crisis, the law set limits for six major pollutants.
The Act pushed automakers to produce cleaner, more efficient vehicles, manufacturers to take active pollution control measures in their facilities, and municipalities to shift to a cleaner energy mix.
Under its terms, the Environmental Protection Agency (EPA) maintains and enforces National Ambient Air Quality Standards to protect public health and the environment from these substances and other potential air pollutants.
The Act's most recent update was in 2022, as part of the Inflation Reduction Act. A key part is to reduce methane emissions from oil and natural gas operations by nearly 80%, using data collected remotely by satellites in some instances. The new rules have broad implications for operators and the practice of natural gas flaring.
