One of the goals of this blog is to act as a resource for people who want to learn more about coal tar sealant pollution and the major constituent of concern in it, polycyclic aromatic hydrocarbons (PAHs). To that end, check out what we know about New York and what is happening right now.
If you’re new to the topic here’s a little background. PAHs are a family of complex chemicals called combustion byproducts that, as the name implies, are formed when an organic material (coal, gas, wood, paper, tobacco, food) is burned. Coal tar contains a lot of PAHs and it’s what’s left over after coal is purified to make steel. Coal tar sealants are mostly a mix of coal tar and clay for the preservation of parking lots, playgrounds and driveways. If you want to learn more, there are some video links on right side of this page.
Here’s what is known about PAHs in NY:
- PAHs affect children.
- The largest source of toxic PAH is from coal tar sealants.
- Area lakes have high levels of PAHs from coal tar sealants.
- The typical coal tar sealed driveway has more PAHs than the Gowanus River, aka the dirtiest river in America.
- Suffolk County is near a ban.
PAH Affects on Unborn Children
This is a fascinating series of ongoing studies done right in New York. Researchers strapped air quality monitors on 249 pregnant women. The women were monitored through their pregnancy and the children have been tested at least until they were 5 years old.
This work done by the Columbia Center for Children’s Environmental Health with grants from the EPA found decreased birth weight and head circumference, developmental delays to the children of higher exposure categories by age 3, and lower IQ scores by age 5.
“This finding is of concern,” said researcher Frederica Perera. “IQ is an important predictor of future academic performance, and PAHs are widespread in urban environments and throughout the world. Fortunately, airborne PAH concentrations can be reduced through currently available controls, alternative energy sources and policy interventions.”
New York Academy of Sciences Harbor Study (NYAS)
A few years back the New York Academy did a series of research papers on pollutants affecting the quality of New York Harbor. One of the pollutants of concern was PAHs. The Academy produced a report entitled, “Pollution Prevention and Management Strategies for Polycyclic Aromatic Hydrocarbons in the New York/New Jersey Harbor.” The report is one of the most comprehensive reviews of PAHs sources in an urban area and found that the largest source of the most toxic PAH, BaP is from coal tar pavement sealants.
This is a dramatic and important finding. Here’s why. Coal tar pavement sealants are ONLY used on parking lots, playgrounds and driveways. New York City, the most walkable, car-free city in America, has the least amount of this land use per capita and yet STILL coal tar pavement sealants are a major source of the most toxic PAH in its environment! So what does that say about the rest of the country?
Unfortunately, the NYAS was unwilling even to suggest a ban of the materials. Instead they recommended eliminating parking areas, encouraging New Yorkers to take more public transportation, changing over from asphalt surfaces that require sealants to concrete and doing more studies. All good things, but it missed the mark in spite of urging to the contrary!
USGS 40 Lakes Study
- Coal-tar-based sealcoat is the largest source of PAH contamination to 40 urban lakes studied, accounting for one-half of all PAH inputs.
- Coal-tar-based sealcoat use is the primary cause of upward trends in PAHs, since the 1960s, in urban lake sediment.
Gowanus River vs. Your Driveway
One of the pollutants of concern of the Gowanus is PAHs from old industrial processes and combined sewers. I did a post about this back in February; where the concentrations in the Dirtiest River in America were compared with a typical coal tar driveway sealant. The highest? Driveways by more than 20 times!!
Here’s a quote or two from the EPA about the Gowanus:
“It’s not to the point where we’re saying no boating, but we’re saying if you’re going to boat, be very careful, and maybe don’t take your little kids with you,” said Environmental Protection Agency Regional Administrator Judith Enck.
“Be very careful not to fall in,” said Enck, who also urged people not to eat fish or crabs from the canal. “Do everything possible to avoid contact with the water.”
“The Gowanus Canal is one of the most contaminated water bodies in the country,” Enck said.
“Contamination…is widespread and may threaten people’s health, particularly if they eat fish or crabs from the canal or have repeated contact with the canal water or sediment.”
So this stuff is OK on a playground or driveway?
Suffolk County, NY Near a Ban