New Brochure Unveiled Among Unimpressed Audience
Last month the Pavement Coatings Technology Council (PCTC) unveiled their latest attempt to get people to continue to use coal tar sealers (or their new sanitized name “refined tar sealers”). It was presented at a session with at the National Pavement Expo in Charlotte, North Carolina. More than 2/3 of the audience left before the session was over.
The Q & A portion didn’t go so well for the industry as it was kicked off by an applicator who said:
“How do you say it isn’t toxic, when I was literally bleeding from my eyes and a wart thingy was growing out of my forehead?”
She said that when she stopped applying a mix of 70% asphalt and 30% coal tar her symptoms went away. The panelists said they had never heard of such a thing. Actually this condition could be related coal tar exposure to the eye which is a well-known malady that causes a “ulceration and infiltration of the cornea” and similar symptoms to pink eye or conjunctivitis.
While much of the spin is well-worn, much repeated lore, it seems to moved into a new territory: direct information to consumers. Previously the information was often provided to applicators to assure them of the safety of using coal tar sealers. This 12 page brochure is focused on consumers to address their specific product-related questions.
It attempts to answer the following questions/topics:
- Is sealer a health hazard?
- I’ve heard it causes cancer. Is this true?
- I heard something about it becoming hazardous to dust in houses
- Why does it have such a strong smell?
- Does sealer hurt the environment?
- Why have they been banned in some areas?
- Is asphalt emulsion-based pavement sealer safe?
Each one of these deserves a full review, but let’s take a look at the first:
Is sealer a health hazard?
To be transparent, the relevant section of the brochure is included so the reader can see what is actually being claimed.
Air Sampling Safety
The above graphic clearly states the authors believe this product is “safe” and “poses no health risk.” The
air sampling study referenced is from 1992 and was authored by the US’ main refiner of coal tar products, Koppers, Inc. The only published information found to date is just in a magazine article and not a peer-reviewed journal article.
Not sure any lawyer or toxicologist would think saying that any activity “poses no health risk” is a good idea. All activities in life involve health risk and the key is whether it is “acceptable” or not. The graph shows there is an OSHA standard for PAH exposure on one end of the spectrum, but it also shows that human health affects have been seen in pregnant women 1,000 times less than what the industry found that “poses no health risk.” While there are some unanswered questions, this shows that the safety of this product is far from being declared safe.
At best this industry study (only one?) is dated (almost 25 years old now) and analytical methods and equipment are much more accurate today. The 1992 study including the lowest detectable levels for naphthalene at only 120 nanograms per cubic meter, but a
USGS study was more than 100 times greater level of measurement by sampling down to 1 nanogram per cubic meter.
But even with the difference in reporting levels, there are some curiosities when comparing the two studies. For example, the industry’s “Head Space Test” was a sampling on the pavement within 15 minutes of a sealer application. At this point they found that “all airborne data for volatile and semivolatile organics were at or below the analytical limits of detection.”
However the USGS found not just the presence of the chemicals but that the total of just 8 of the PAHs exceeded the OSHA standard of 200,000 nanograms per cubic meter after just one hour of curing. Why the difference?
And who would you trust the health of your family or the value of your property to: a federal agency tasked with scientific research which has gone through vigorous peer review and published or an out-dated industry publication in a trade magazine?
Not Toxic?
The most important next part of their claim is with the second graphic implying that coal tar sealers are not toxic. There are a couple of ways to talk about this.
First, coal tar sealers have 35% or so coal tar pitch. Coal tar pitch is classified as a known human carcinogen. Does anyone logically think that something with that high of a percentage of a known human carcinogen magically becomes non-toxic by adding some sand and clay to it?
Second, it is only by special exceptions that coal tar is not listed as a solid waste. The text of a
Colorado publication explaining this is included below, but look at this quote:
EPA based its decision to exclude coke by-product wastes on the fact that recycling these wastes did not have a significant effect on the chemical composition of the products. Further, coke by-product residues are often managed as raw materials rather than wastes, thereby reducing the risk posed to human health and the environment because the material has an intrinsic value that promotes its safe management.
So it is ok to recycle this byproduct in the EPA’s mind at the time because they think people or the environment would NOT be exposed to it. Note that the document says that risk would be “minimized” if it were kept away from humans and the environment. It wasn’t because it was non-toxic. Guess the EPA didn’t consider coal tar pavement sealers, where people live and children play in their assessment.
Third, look at the research on coal tar pavement sealers. They have been found to affect fish, frogs, and other aquatic organisms in the field and laboratory even down to the DNA level. The characterization of this products extends the risk to children and pregnant women. Here’s a
compiled list of references to the effects of the product or its ingredients. Would you still say it is non-toxic?
We’ll hold off the discussion of toxic waste characterization for a future post.
So maybe those that walked out on the presentation of this material have figured out one thing for sure: if it requires double speak to sell your product, if it burns you to put it down, and if you can’t assure your customers to its safety, then maybe you’ll just pass on using it at all.
