Small Airborne Particulate Matter Linked to Increased Deaths in the US

Scientists at NYU Langone Medical Center and elsewhere conducted what is believed to be the largest, most detailed study on the effect of small chemical particles in the air on mortality rates in the US. This study was particularly notable, because all of the data used came from government and independent sources.

The researchers found that even miniscule increases in these small particles in the air led to a 3% increase in the rate of death from all causes, and an increase of approximately 10% in the risk of death due to heart disease. The risk of death from respiratory diseases for nonsmokers was even higher at 27%.

These fine particles are usually made of chemicals such as mercury, arsenic, and selenium. In addition, they can transmit harmful gaseous particles such as sulfur and nitrogen oxides. These chemicals escape the body’s defenses and can be absorbed deep into the bloodstream and lungs.

The investigators evaluated health and diet survey data conducted by the NIH and the AARP for people that lived in six states. They then cross-referenced the data with information on the amount and type of particulate matter from the EPA’s Air Quality System along with other databases.

The team statistically ruled out other variables that affect health such as level of education, age, race, ethnicity, body size, marital status, alcohol consumption, and whether or not the participants smoked.

Surprisingly, when the researchers analyzed the data from California which has the strongest controls on air pollution, they found the same risk of death as in other states which do not regulate air pollution as aggressively.

The next step will be to determine which components of particulate matter cause the most harm and whether they come from coal-burning power plants, chemical plants, or auto exhaust. Finding out this information should have a significant effect on the development of health policy in the US.