Despite major gains, New York City’s air quality remains one of its most pressing environmental and public health challenges. As we reported last year, the City found that an estimated 2,700 “premature” deaths every year can be tied to ozone and fine particulate matter, two leading air pollutants.

On Wednesday, Mayor de Blasio signed legislation requiring the City’s Department of Health and Mental Hygiene to conduct neighborhood air quality surveys with a focus on street level data, and to release the results to the public on an annual basis.

The Determine of Health must now also determine how concentrations of air pollutants vary across the city, and locate the source of such pollutants, with an eye to factors like local traffic and building emissions.

The bill’s chief sponsor is City Council member Corey Johnson of Manhattan, chair of the Council’s Health Committee.

Why good data on air pollution is important

Identifying the actual sources and health impacts of air pollution -by neighborhood- is a formidable challenge but has real potential to save lives.

Air pollution has an especially powerful impact on New York City’s low-income and communities of color. A 2014 study by the state Comptroller found that the Bronx has the highest age-adjusted asthma death rate “by far” among all counties in New York State: 43.5 deaths per million residents in the Bronx, as opposed to the state average of 13.1 deaths per million.

Progress is being made. The City reports that the estimated number of deaths attributable to fine particulate pollution has been dropping– by an impressive twenty-five percent between 2005-07 and 2009-11. Particulate pollution – in the form of small particles and droplets – is emitted by many local sources, including heating fuel, power plants, and motor vehicles.

Smoke rises from a building burning heavy oil. Credit: Environmental Defense Fund/Isabelle Silverman

In the last several years, the City has moved to ban heating fuels that create the most fine particulate pollution when burned. It is also establishing a marine barge and rail network in order to take garbage trucks off the roads. Efforts to address car and truck pollution have often turned contentious. Witness the battles over the East 91st Street Marine Transfer Station or congestion pricing.

Tackling ozone pollution -which contributes to several hundred deaths annually- is even more challenging because it requires local as well as regional action. The pollutants that cause ozone in New York City are emitted locally and come from other states. Ozone is also exacerbated by rising temperatures.

New York City has made “extraordinary progress – air pollution is at the lowest point in the city’s modern history,” Mayor de Blasio stated at a press conference this week. “But…air pollution remains a leading environmental threat to our health – obviously, particularly related to asthma and other respiratory diseases…And we do not believe that we have gone as far as we can go.”

One of the key goals of Mayor de Blasio’s OneNYC plan is that New York City will have the best air quality of any large U.S. city by 2030. Part of accomplishing that objective is obtaining better information about air quality at the neighborhood level, and then alerting the public about what they are actually breathing.

The need for more regular data

The Department of Health measures air quality throughout the year in every community district but the information it releases publicly is sometimes several years old. Data about fine particulate matter pollution on the City’s Environment & Health Data Portal appears to be from 2014, while data on ozone pollution is from 2009-10.

According to the legislation signed by the Mayor this week, Intro. 712-A, the Department of Health will be required to submit a report to the City Council every April with the results of an annual community air quality survey using the most recently available data. The report will also be posted on the Department’s website.

Establishing a reliable, and regularly updated, baseline of information is critical for good public policy and effective dialogue about air quality. Statistics about air pollution are cited repeatedly, for example, as communities battle over issues like where to locate new trash facilities, and which neighborhoods are already overburdened.

The need for more street level data

The legislation also requires the Department of Health to measure air pollution at the street level and to determine how factors like traffic and building emissions impact air quality.

This is a critical point. The Department of Health says that it currently takes air quality measurements at 150 locations throughout New York City each season of the year. When we spoke with the Department last year, they explained that air quality monitors are attached to structures like street lamps, but not necessarily at ground level.

street scene
Traffic in Manhattan. Credit: Chuck and Sarah Fishbein

Environmental justice advocates argue that pollution must be measured at the point where emissions are released -and people are breathing- to understand its true impact. In the case of car and truck traffic, the closer to the tailpipe the better.

More data is needed about the impact of car and truck traffic on New Yorkers. Think about the number of times you (perhaps accompanied by a child or someone in a wheelchair) have waited for a light to change as trucks and cars idle around you.

What exactly are we all breathing?

The City has asked the same question. In 2011, the Department of Health began to look at areas with high traffic intensity in order to understand whether cancer causing pollutants like benzene and formaldehyde were being emitted at higher rates there as compared to low traffic areas. The City found that street level concentrations of benzene and formaldehyde in high traffic areas were significantly higher, by 83% and 45% respectively.

Air Pollution: What exactly will the City be tracking?

The Department of Health will continue to track the following “pollutants” at the neighborhood level: particulate matter that is less than 2.5 micrometers in diameter; nitrogen dioxide; nitric oxide; sulfur dioxide and ground-level ozone.

“The findings will help guide our work to curb pollution and track our progress towards our ambitious [OneNYC] goal,” the Mayor concluded as he signed this week’s legislation.

Building on its existing community air quality surveys, the Department of Health is now required to:

  1. Measure pollutants at street-level monitoring sites across the city every season of the year. The goal is to ensure that the number of monitoring sites provides adequate information to assess the range of common emissions sources and neighborhood pollutant concentrations;
  2. Determine whether and how concentrations of pollutants vary across the city and the relationship, if any, of such concentrations to local traffic, building emissions and other factors;
  3. Identify the major local sources of pollutants that contribute to local variation in concentrations;
  4. Identify patterns of pollutants by geographic area, by source, and by season or time of year;
  5. Produce maps indicating the varying concentration levels of pollutants across neighborhoods and by pollutant;
  6. Produce an annual report for the public, which will include the findings of completed or ongoing health surveillance and research studies using air quality survey data to estimate population exposure to pollutants.

(The six points above are adapted directly from the legislation signed into law on Wednesday.)

The City Council has also pushed the City to bring its Air Pollution Control Code into compliance with more stringent air quality regulations promulgated by the federal government and the State.

The City’s air code had not been thoroughly overhauled in 35 years, said Council Member Donovan Richards, who sponsored legislation requiring the update earlier this year.