Overall, the latest cars and trucks have come a long way in reducing harmful exhaust chemicals, such as carbon monoxide, nitrogen oxides, sulfur dioxide, hydrocarbons, and benzene. Nevertheless, vehicles still produce pollution that is harmful to humans. A catalytic converter cannot render these chemical emissions less harmful until warmed up (a catalytic converter warms up faster when a vehicle is driven as opposed to idling). A caravan of idling vehicles, such as at a drive-thru or school pickup queue greatly increases these emissions. Idling emissions are more toxic during hot and cold weather extremes, and carbon monoxide poisoning remains a threat for occupants of idling vehicles in enclosed spaces or deep in snow banks.
Diesel engines in commercial trucks and school buses are durable and economical sources of power, and newer diesels are 90 percent cleaner than those manufactured prior to 2010. But older diesels – which can last 20 years or more – emit toxic pollutants, such as particulate matter and volatile organic compounds, that cause significantly higher levels of harmful emissions when idling.
Air pollution is connected to a host of health issues, including respiratory illnesses (such as asthma, bronchitis, and emphysema), pre- and neonatal health risks (including low birthweight, premature birth, and infant mortality), stroke, heart disease and heart attacks, behavioral conditions (such as attention deficit hyperactivity disorder (ADHD)), cognitive issues (including IQ decrements and dementia), lung cancer, and premature death.
For more specific information about how each pollutant affects individual health, see NOACA's most recent Air Quality Trends Report.
Children and the Elderly
People with existing heart or lung disease, asthma, bronchitis, or other respiratory problems are most sensitive to the health effects of fine particles. The elderly and children are also at risk.
A 2018 World Health Organization (WHO) report on air pollution and child health reveals that when pregnant women are exposed to polluted air, they are more likely to give birth prematurely, and have small, low birth-weight children. Air pollution also impacts neurological development and cognitive ability and can trigger asthma, and childhood cancer. Children who have been exposed to high levels of air pollution may be at greater risk for chronic diseases such as cardiovascular disease later in life. One reason why children are particularly vulnerable to the effects of air pollution is that they breathe more rapidly than adults and thus absorb more pollutants. They also live closer to the ground, where some pollutants reach peak concentrations – at a time when their brains are still developing.
Furthermore, children don’t behave like adults, and their behavior also affects their vulnerability. They are outside for longer periods and are usually more active when outdoors. Consequently, they inhale more polluted air than adults typically do.
As people age, their bodies are less able to compensate for the effects of environmental hazards. Air pollution can aggravate heart disease and stroke, lung disease such as chronic obstructive pulmonary disease and asthma, and diabetes. This leads to increased medication use, more visits to health care providers, admissions to emergency rooms and hospitals, and even death.
Ozone and Particulate Matter (PM) (especially smaller, fine particle pollution called PM2.5) have the greatest potential to affect the health of older adults. Fine particle pollution has been linked to premature death, cardiac arrhythmias and heart attacks, asthma attacks, and the development of chronic bronchitis. Ozone, even at low levels, can exacerbate respiratory diseases.
