The sky isn't falling-the facts about pavement sealers and safety. 

In the last few years since the City of Austin Texas banned a particular sealer some companies and contractors have resorted to twisting half-truths and often downright lies in an attempt not to "sell" their products but to "scare" people away from their competitors. So we have allowed a published author to make some in-depth observations on the subject.

This article is designed to clear up some of the misconceptions about various Sealcoating materials and their environmental and health effects which have been used and abused by some companies to promote their products over products using other materials. In particular it's about coal tar-based sealants, asphalt-based sealants, and the other type of sealants which are sometimes called rejuvenator's or improperly referred to as "oil-based" sealers.

I won’t even go into the “solvented” products, sometimes called Gilsonite because of the mineral asphalt used or called “rejuvenators, or incorrectly called “oil based” (oil would dissolve asphalt as will the over-application of these products-they must be applied water thin) They are notoriously slick when wet, wear quickly, and are banned in 13 NE states for their environmental impact because of the huge amount of VOC’s released into the atmosphere, since most contain approx 40% naphtha (paint thinner). So these definitely are bad for the environment. Do a web search for OTC or Ozone Transport Commission to see the 13 states where they are banned.

To start with the most recent and thus most currently abused item, which is being abused by some people in their advertising:
The city of Austin, Texas banned the use of coal tar-based sealants several years ago. What most people don't realize is that this was an effort which took over 10 years by the proponents and which was voted down by the Austin City Council year after year, and was only passed after the proponents were able to elect some people who shared their viewpoints to that City Council. What many people do not understand about Austin Texas, unlike this author who was born and raised in Texas, is that while Austin, while it is our state capital, is also referred to by residents as the "San Francisco" of Texas. This came about, first with the relocation of Dell Corporation to the Austin area, and the following relocation of many other "Silicon Valley" companies to the Austin area who supplied Dell or related products and the great influx of workers from the west coast for these industries..
Coming from California for coal tar sealers (contrary to popular belief) have never been banned, but are not used because they are far more expensive on the West Coast, as opposed to the East Coast; the influx of residents from California to the Austin area had never experienced the smell of coal tar sealer which is far stronger than that of the asphalt-based sealers commonly used in California. Coal tar sealers being made from the same basic material (coke oven car) have the same smell as creosote, which is a very strong chemical smell and is a highly restricted product o the OSHA & EPA lists.
However coal tar sealers contain virtually no creosote, but they do contain creosols which are the component that creates the smell in creosote. Because of this, many of these new citizens of our state were sure that this sealer must contain creosote and be harmful, because anything that smells like that certainly couldn't be good for you.
They then started a campaign to abolish this type of sealer. They tried for many years and continued to fail including hiring many of their own firms to conduct so-called “tests” which of-course always got the results they wanted. They finally got the USGS to conduct an experiment on one pre-picked area which is the only area of Barton Springs Creek (an inner-city waterway) that contains elevated levels of PAH’s which later the USGS admitted was not done according to their own testing criteria. The results of this flawed test, along with the newly elected members of the Council were finally able to get the ban passed for coal tar sealers within the city limits of Austin. For you non Texans remember or State government only meets every 2 years and Austin was basically a sleepy college town with the biggest thing in town being the main campus of the University of Texas. Barton Springs Creek runs directly through the center of town and now gets far more runoff from roads, parking areas, lawn chemicals, etc. than in the past and yet is still in the 800’s on the list of pollution levels in inner-city waterways.
Of course, like most major metropolitan areas, Austin is surrounded by dozens of smaller towns, which actually abut the Austin city limits and in those cities coal tar sealer is still allowed.

However, disregarding all of the facts about how this whole situation came to be some people in their advertising are heavily stressing how coal tar sealers are banned in Austin and use that as some type of "proof" that coal tar sealers are not friendly to the environment and are hazardous to your health. Other people (and sometimes the two are combined) also used studies conducted by OSHA, and NIOSH which were done many years ago (in the 1960’s) on the coke oven tars and which did show that occupational exposure to the tars could be carcinogenic.
Now this is NOT the same coal tar which is used in sealer, which is a refined coal tar known as RT 12, and to compare the two is much like comparing gasoline with crude oil. The findings about the carcinogenic material were for workers who worked in steel mills "mucking out" the raw coal tar from the coke ovens, where it is produced as a byproduct. Of course these workers were directly exposed to the raw tar in an industrial environment in tests done many years ago, before OSHA had as many protective clothing requirements for workers as they do today and were based on exposure levels of 40 hours per week over a 20 yr. period.

There has never been any test showing that RT 12 the refined coal tar used in sealer causes cancer in human beings either in its liquid state, or especially not in its dried state on pavement. There have even been tests done by the Sealcoating industry where glass "bubbles" were placed over what sealer, which had just been applied to pavement and the gases released by the sealer as it dried were captured and found to be well below the acceptable PEL levels set by NIOSH for occupational exposure. And certainly no gases are released once the sealer is fully dry.

As for the environmental part of the study in Austin that was done by collecting samples of rainwater from unsealed pavement, pavement sealed with asphalt-based sealer, and pavement sealed with coal tar-based sealer. In these tests are coal tar-based sealer did show to have higher levels of poly aromatic hydrocarbons (PAH) than the asphalt-based sealer or the unsealed pavement. The problem with those tests was they did not allow for any of the variables such as what the pavement had been exposed to, the different products used, and the different conditions of the pavement. Thus the testing violated USGS criteria which require a “control” and that all tested areas be equal.
My personal observation of these tests has always been that of the three items tested coal tar sealer does not allow motor oil or other such chemicals, which commonly dripped from vehicles to penetrate into the pavement below. Thus any substances on the pavement surface such as motor oil, which would be almost purely made up of poly aromatic hydrocarbons (PAH) or substances from car exhaust settled on the pavement, would tend to be washed off the pavement by rain and show in the test results; where the same type substances would penetrate into unsealed pavement or pavement sealed with asphalt-based sealers.

Coal tar-based sealcoat was the first pavement sealer invented in 1933 and this was exactly the reason for its invention. It was invented by a chemist working for the Standard Oil Corporation to protect the pavements in their gas stations from spilling motor oil, gasoline, and other such chemicals which would penetrate and damage the pavement. So at least in my opinion; in these tests, coal tar sealers may be being penalized for doing the very thing which they are designed to do, which is to protect pavement from these substances.

However, in advertising these tests have also been twisted and worded in such a way as to make people think coal tar sealers are an imminent and great danger to the environment. Since they have been in wide use since 1933 it would seem that there would be areas of the country for the environment had been harmed far more than that in Austin, Texas if this was actually the case. (These sealers were originally produced in “steel country” where coal tar was easily available-mainly Ohio and spread slowly across the country not becoming a common procedure everywhere until the 1960’s.)
Coal tar sealers can cause a burning sensation to people with fair skin and if the sealer is left on the skin can cause a chemical burn. However, in studying the NIOSH classifications for both chemicals, asphalt will also cause a chemical burn, when left on the skin, it just generally takes a little longer to do so.

The main thing that bothers me about all of this is that the people distributing this “advertising” and twisted information are not actually concerned about the environment or about the occupational exposure of workers using these products at all.

But instead are misrepresenting these tests, and the fact that only two cities that I know of in the United States (the other being Madison Wisconsin, who directly based their ban on the Austin Texas ban) to make it appear that coal tar Sealcoating is a definitely carcinogenic and or definitely harmful to the environment and thus you should use their product instead.
They always conveniently leave out what the NIOSH, OSHA,and EPA evaluations of the chemicals in their products are.

Some of the brochures that I have seen circulated and some of the misinformation on websites that I have seen has taken this one action by one city in Texas, which is by far not the largest city in Texas, and used that plus tests from decades ago and their results about carcinogens, which related only to workers in steel mills who actually cleaned out the coke ovens and taken this to the point of trying to make the reader think that you or your property visitors might actually get cancer from having used these products, or that you are harming the environment by using them. One ad actually said that you might be sued for allowing these products to be used on your pavement (not likely unless you are in Austin or Madison but a half-truth since these days anybody can be sued for anything.) However one product I saw using this logic would be slick in the rain and you would be far more likely to get a “slip & fall” suit because their product could not hold silica sand which is always added to other sealers for added traction & durability.

Please understand that I am absolutely for environmental protection, and certainly for the protection of human beings and workers as is the NPCA which allowed the publication of this article.
However, they neglect in these brochures and advertisements to mention that several years ago all asphalt paving equipment was required to have a ventilation system to take the fumes coming from the hot asphalt and blow them away from the operators of the asphalt paving equipment because the fumes from asphalt have definitely been shown to be carcinogenic (however this was mainly a precaution, because the test showed results only on animals and not on human beings). But certainly, if asphalt fumes from the pavement itself are considered carcinogenic the fumes that are given off as the asphalt-based sealer dries would contain the same carcinogenic components, however, that part is conveniently left out of these misleading advertisements.

I also would like to state that I am not a scientist, but I have spoken with many chemists who have studied these issues in great detail, I have read the various Austin votes, tests, and the last set of tests, as well as numerous tests done by the PCTC (the Pavement Coatings Technology Center-an independent industry organization at the University of Nevada Reno who have not found occupational hazards, much less hazards to using the pavements later on after running extensive batteries of tests over a period of years). My only complaint is not from a scientist’s point of view, but is a complaint against those who take certain findings of a very limited nature then for their own financial gain blow them far out of proportion in order to sell their products. It is my personal viewpoint and has been all of my life that any product or service should be able to be sold on its own merits without having to criticize or make bad remarks about other companies or products; and I still feel that way. If a product is better, let it be sold on the merits of it being better not on the fact that something else might be worse. Especially by fabricating “evidence” the other product is worse.
The argument is actually of little merit anyway, because coal tar sealers are a dinosaur and are gradually moving towards extinction. Not because of their properties or chemical characteristics, but because they are produced as a byproduct of the manufacturing of steel, and we no longer make steel in the United States in any appreciable quantity, meaning that the coal tar used for sealers must be imported from China at a high cost and the supply is not dependable. Most of the steel made the day in the USA is recycled. The recycling procedure does not produce coal tar.
Also there have been no recalls of many products on the market which you might use every day, such as dandruff shampoos. Treatments for skin conditions such as eczema or psoriasis many cosmetics and other products which contain refined coal tar as one of their ingredients; the important word here being refined, because the tests showing carcinogens were done on the-based coal tar. Not on refined coal tar, such as used in sealer, and these other products.

Because of his limited market, the price of coal tar is expected to continue to increase rapidly. It has doubled in many places in the last two years alone; so all of these arguments are really becoming a moot point as we move into the 21st century. Of course asphalt-based sealers will continue to rise in price depending on what the price of crude oil does. In writing this article, I have not done so lightly. I have spent many hours looking through the websites of OSHA, the EPA, and NIOSH. And being from Texas, I have watched the incidents in Austin happen, over years and years of personal observation and seen the great lengths that the opponents of coal tar sealer went to, and including getting tests done that were not to the criteria of the testing organization (and which the USGS had to issue a letter of clarification admitting they did not follow their own criteria for testing)
All in order to prove their point and get what they wanted. That's not so much a matter of Sealcoating as it is a matter of the American political system and the majority getting what they want. Fine with me, that’s our system of government and if the majority votes a particular way in Austin that’s fine; but it doesn’t “prove” anything except the will of the Austin City Government and the people who lobbied them for a decade to get this passed.

You may ask then why am I writing this article and the answer is quite simple. I've written this article and done a great deal of research I have done to be sure, what facts I stated were correct to the very best of my ability so that people who are good honest, hard-working, contractors using the best materials they have available in their area (because in the eastern United States. There are many areas where there is no sealer is readily available except coal tar), whose businesses are being hurt by misleading advertisements and websites that would leave someone thinking that these products which have been used safely for decades, over 75 years now, are now of some type imminent danger to the person purchasing the product or hiring a contractor.
If the manufacturer wants to sell their materials, or a contractor wants to prove that his materials are better than his competitors, let them stand on their own merits, and the quality of their workmanship and their products.
Do not resort to the "low end" tactic of running someone else down with fabrications and half-truths to make yourself look better. Most of us were taught by our parents, way back in childhood, that was never a very good idea and in the end, only made the person running down the other one look worse. And the same is still true today.
If these statements were true our many “acronym” agencies (OSHA, EPA, NIOSH) would outlaw the manufacture of such dangerous products…IF they were as dangerous as these advertisements claim. A little common sense should make that obvious.

As I said I am not a scientist and I am certainly not the be-all and end-all authority on the subject and I do not wish to have anything on the NPCA’s fine web site which is incorrect because of something I may have missed.
If anyone has links to documentation by accredited agencies of research they have done proving that anything I have said in this article is incorrect or even bordering on being incorrect. I will be more than happy to make corrections and include any links supplied to me. This can be done by simply using the main NPCA e-mail and typing the name of this article in the subject line. If anyone wishes to do their own research; you can do Internet searches for asphalt under the search phrase CAS 8052-42-4 and for coal tar, under the search phrase CAS 008 007-45-2. However, do be aware that these are just starting points for your research because both of these are the CAS numbers for the base product themselves. Not for the refined product as it is finally used in pavement.
 

This article was written by Don Turner of Turner Pavement Consulting.
A contractor for over 23 years in all aspects of the industry from sealcoating/striping/repair/crack sealing/and paving and who has been a speaker at more national Pavement expositions than any other "contractor" speaker.
In the interest of full disclosure: he is also the sole distributor of a product called SurfaceMax which is added to asphalt emulsion type pavement sealers to improve & modify performance characteristics and thus does have a direct financial interest in the increased use of asphalt emulsion based pavement sealers.

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Last modified: September 22, 2009