Air Pollution Health Crisis
“Long-term exposure to fine particulate air pollution was associated with natural-cause mortality, even within concentration ranges well below the present European annual mean limit value.” European Study of Cohorts for Air Pollution (ESCAPE) Effects Report. Lancet. 2014
NOx from Diesel Emissions Cause Chronic Disease and Death
Deadliest Emission: Particulate Matter (PM)
All diesel emissions are not equally deadly. NOx is bad, but PM is worse.
Exposure to NOx raises risk for lung cancer an estimated 3-4% for every 10-μg/m 3 increase in NOx (95% CI: 1%, 5%). In 2014, 7% of the urban population of the EU-28 were exposed to NOx concentrations above WHO and EU standards, with 94% of all excess exposure occurring due to traffic.
For human health the most dangerous diesel emission is PM 2.5 and smaller — atmospheric particulate matter with a diameter less than 2.5 micrometers, small enough to invade the smallest airways and even enter the bloodstream.
There is no known safe exposure level. A recently published 2016 Harvard study found that both short- and long-term exposure to PM 2.5 were associated with increased mortality at exposure levels well below EEA/WHO standards and even below the more stringent U.S. EPA standards.
PM emissions are a global health threat. Even at WHO target levels, there is strong evidence that particulate matter (PM) emitted mainly by diesel road vehicles is associated with increased risk of heart attack, diabetes, several cancers, birth defects, dementia, and death.
The Biggest PM Danger May Also Be the Smallest
Researchers are only just beginning to investigate the health threats posed by exposure to ultrafine particulate matter in the nanoparticle size range. Particulates this small can enter the bloodstream through the gut, lungs, and mucus membranes; cross the blood brain barrier; and potentially affect multiple organs and metabolic systems. As our understanding of the associations between ultrafine PM and inflammation, oxidative stress, and neurologic damage has grown, so has the concern in medical, environmental, and health research communities.
- HEART ATTACK. Exposures to PMs as short as a few hours can trigger heart attack and sudden cardiac death even at levels 50% below current European limit values (25 μg/m3 for PM2.5, 40 μg/m3 for PM10)
- STROKE. Short-term PM 2.5 is also strongly linked in research to elevated blood pressure, stroke, and stroke-attributed hospital admissions.
- LUNG DISEASE. Long-term exposure to PM 2.5 increases risk for chronic obstructive pulmonary disease (COPD) and lung cancer by ~20%.
- ATHSMA. Increases in ambient NOx, NO2, PM10, PM2.5 are strongly linked with childhood asthma attacks requiring hospital admission.
- DIABETES & METABOLIC DISEASE. Both NOx and PM2.5 are significantly associated with blood glucose levels, obesity and type 2 diabetes in children and adults.
- CANCER. Several cancers are more common in people exposed to PM2.5, lung cancer (~20% increased risk), liver cancer (34% increase for a -μg/m).