Sunday, April 20, 2008

Sorting Out The Health Claims Over Synthetic Turf Fields

A decision by New Jersey health officials to close two synthetic turf fields over concerns of high lead levels has sparked a spate of news coverage raising fears about the safety of these increasingly popular sports venues.

For example, today's Washington Post has a story (Metro section p.4) on the potential hazard: "U.S. Investigates Artificial Turf's Lead Levels." The other night ABC News ran a more inflammatory piece typical of television news coverage, featuring a couple of activists who make it sound like artificial turf fields are nothing more than toxic waste dumps.

The Curmudgeon has some familiarity with these issues. As a member of the Board of Directors of the Arlington Soccer Association, which plays many games on artificial turf fields, he has looked into the issue. (The photo here is of the beautiful synthetic field at Washington-Lee High School in Arlington.)

Here's some reassuring news: the likelihood of any significant health hazard from articifial turf fields is quite low. That's not to say the risks shouldn't be investigated and quantified. But you certainly shouldn't worry too much if your children are playing on one of these fields.

Synthetic turf fields are becoming increasingly popular, especially in densely populated urban areas. The reasons are pretty obvious. Today's artificial turf is far more user-friendly than the old "astro-turf"--it's softer and less abrasive. Arlington recreation officials tell us that a typical lighted synthetic field in the County will get five times the usage of a "grass" field. We put grass in quotation marks for a reason: most grass fields quickly turn into dirt fields, with a few uneven clumps of grass, due to overuse.

One reason you get more usage from a synthetic field is that it doesn't have to be closed when it rains or when the field is wet. A week ago, after just one day of moderately heavy rain, Arlington's grass fields were closed for four days because they were wet and thus subject to damage if used. Another reason for more usage is year-round use. Grass fields typically need to be covered and off-limits in the winter. Also, synthetic fields don't need to be taken out of use for rehabilitation and rest every three of four years. Even after taking precautions to limit damage to grass fields, most still get destroyed by overuse.

In a dense urban area like Arlington, where land is at a premium, being able to quintuple the use of a given area by installing artificial turf makes the decision a practical no-brainer. The fields are expensive--between $500,000-$1 million, depending on the infrastructure needs at a given site--but over the long term they are less expensive given the greater use and lower maintenance. That's why Arlington, which has already installed seven synthetic fields, is busily planning three more, and we hope, more after that.

So, barring some serious health issue, artificial turf fields are here to stay and you'll see many more of them in the years to come. The current estimate is that there are 3500 in the U.S. today, a number that could easily double in just a few years.

What of the health issues? First off, you need to understand that grass fields have health issues too. It is true than nothing, including synthetic turf, beats playing on a well-maintained grass field. But few grass fields are in such condition, nor can they be kept in such condition unless play on them is severely constrained. Most are rutted, uneven, lumpy, bumpy surfaces, often with low spots that accumulate water and leave muddy areas days after the last rain. Running and playing on such a surface significantly raises the potential for many injuries.

Also, while people like to think of grass fields as some kind of organic commutation with nature, there's nothing natural about most grass fields. To grow grass in an urban environment requires chemicals--fertilizers, weed killers, insecticides. (It also requires a lot of fresh water.)

In the Washington Post story today, one New York lady who is on a mission against synthetic fields complained: "If I put a piece of synthetic turf on your desk, then I take it away, these pieces of recycled tires will be sitting on your desk. The question is, how does that pose a health risk to young children? Kids are bringing this into their homes. It's on their sneakers."

That's nice, but the same thing happens on a grass field. Kids bring home the chemicals used to treat the fields on their sneakers--and their clothes, their skin, their hair, etc. The difference is that you can't even see these chemicals and you generally don't know how much is there or when the chemicals were applied. (Kids also bring home mud, sand and grass clippings from such fields, which any soccer dad knows will have to be cleaned up if not intercepted at the front door.)

So in a sense this debate is little like the surreal debate surrounding nuclear power. Activists get all up in arms about nuclear power, with its fairly limited risks, while ignoring the enormous health and environmental damage done by a similarly sized coal-powered plant. For some reason coal and grass are "safe" simply because they are familiar.

As for synthetic turf fields, the primary worry has been with the ground up recycled tires that provide the "fill" for the green plastic fibers that make up the field. These black particles essentially take the place of dirt. They perform an environmental service as well, by providing a nifty use for old tires that otherwise would have to be difficult to dispose of.

The rubber in tires, however, is not exactly free of chemicals. There's no question that if you were to burn the tires, the fumes would be fairly toxic. Some researchers have raised an issue as to whether simply heating the black tire particles in a synthetic field can also release toxic fumes. One disadvantage of such a field is that on a hot, sunny day, it will get quite warm at the field surface. To date, however, no one has shown that at the temperatures occurring on even the hottest day, any concentration of fumes from tire rubber on an artificial field would accumulate and be inhaled by players.

(In one laboratory experiment, researchers found some potentially toxic fumes when heating tire rubber in an enclosed environment, but the test was far from any real-life situation. You could just as easily use the results to argue that children should not be allowed to play near any high-speed roadway on a hot day, which could keep kids off many grass fields too.)

Another concern was that players on synthetic fields could more easily get staph infections because the fibers on the fields can cause a minor burn-like scrape if slid upon, and the plastic allegedly harbors the staph bacteria more readily than grass. Suffice it to say that this theory has not been proven at all.

The latest concern is about lead. The frustrating thing about reading and viewing news articles on the issue is that they are long on nifty opposing quotes from activists on both sides and short on facts. We still can't tell from these stories whether the lead issue is associated with the tire particles or the plastic fibers, or both. For example, today's WaPo story focused on the tire particles, but a WaPo online story yesterday (from the Associated Press) strongly suggested that the lead issue is associated with the fake grass fibers, and may apply only to older fields made of nylon fibers as opposed to polyethylene. See "Feds Are Looking Into The Dangers of Lead In Artificial Turf."
[Yesteday's story sounded more authoritative. It pointed to the use of pigment containing lead chromate, used to make the field look green, in nylon fibers used by the manufacturer of Astroturf, and noted that 10 other NJ fields, made of polyethylene fibers, had tested negative for lead.]
Let's say, however, that there is at least a potential for some lead exposure from the tire particles. No need to panic. Lead is a known toxin if ingested. Hence, living in a home with lead paint is not much of a hazard in and of itself, but it can be a hazard if young children eat chips of lead paint or inhale lead fumes when the paint is sanded or blasted.

On a playing field, the issue would be whether the tire particles (or plastic grass) emit lead, and if so where it is. If it's just on the playing surface, it's not likely to be inhaled or ingested, and it will periodically be washed (or blown) away so that it won't accumulate. If' it is in dust that comes up above the field, then we need to know whether it is above background levels of lead, and whether it is at a level that is hazardous. Very few people spend a lot of time on artificial turf fields, so it is not like lead in a workplace with someone being exposed eight hours a day, five days a week.

For lead to be toxic, one needs to have a fairly significant exposure. Indeed, we all have lead in our bodies and get exposed to a certain amount of background lead. So a slight elevation in lead on a playing field that someone is on a couple times a week for a couple of hours is not going to be particularly hazardous. (Although we'd agree that hazard should be abated, within reason.)

The bottom line is that synthetic turf fields, like grass fields, probably have some hazards associated with them. Those risks are pretty small, however, and not unreasonable. And they may be more easily managed than those associated with grass fields. Our advice is not to worry. Let little Johnny (or Susie, or Omar, or Ivan or LaToya) play on that nice green, level artificial turf field, and let him/her have fun!
UPDATE: We learned one "hazard" of synthetic fields this afternoon: you may just find yourself spectating at a game played in a torrential downpour, whereas you'd be snugly at home with the game cancelled if it was on a grass field!


Anonymous said...

I wish I had more time to write this comment, but I have to leave soon to pick up/drop off kids at various sports fields. So please forgive me for the stream of consciousness approach and I’ll have to trust spell-check. Your post has been gnawing at me since I came across it while try to find out more info on the NJ lead issues. However, you do seem to have a much more balanced approach than the artificial turf advocates where we live. Around here, if you dare to question their steamroller approach to building these fields, you are usually called a NIMBY, a child-hater, or a sports-hater, and sometimes all three. Yeah right, if I fit THAT description my car wouldn’t be the mess it usually is.

You mentioned that you hate bad science, so I presume you appreciate good science and are familiar with The Precautionary Principle. I think that it is one of the most beautifully crafted documents to come out of the scientific community in many years. If ever there was a situation where it should absolutely apply, it is the building of artificial turf fields. Since so many health and environmental consequences may not show for years or even decades, the tenet that “the proponent of an activity, rather than the public should bear the burden of proof” is vitally important. Those who were (and are) key in building these fields have a moral obligation to ensure their safety for both our children and the environment, and since you say that you are a member of the Arlington Soccer Association’s Board of Directors, and from the tone of your blog I presume that you were involved in their construction. So I guess that makes you at

least partly responsible for any ill effects now and in the future, as well as the positive effects of increased recreational opportunities.

In our county, the Soccer “guys” and county employees who pushed through and are rushing the construction of artificial turf fields appear to have relied on the word of salespeople and manufacturers, and done only research as necessary to refute any concerns by the general public.

I hope that you have done more than that, but Curmudgeon, you scare me. I would hope that the sports community, and Arlington Soccer would rush to embrace the investigation by the CPSC, and insist that they broaden it to include ALL of the potential health and environmental effects of these fields rather than ridicule those who are concerned.. Not only is that the ONLY right thing to do, but it would give you credibility as well.

You casually dismiss the threat of lead contamination, and although I am guessing that it will be found in only a small percentage of fields, any exposure in the name of pursuing a game is too much and completely unacceptable. You use as an example to minimize the effects of exposure “that someone is on [ a field ] a couple of times a week for a couple of hours” and that exposure will be minimal. Is that true for travel teams, or high school varsity soccer? Wouldn’t they be on a field many times that number of hours? Will it be true when more fields are built? To completely blow off what you call a “slight elevation in lead on a playing field” may be a good argument for a lawyer to make, but for someone who parents trust with the health of their kids is completely irresponsible. Lead and lead compounds are persistent bioaccumlative toxics, so if the exposure on a field is enough to tip a child who might be borderline into the danger zone, it is unconscionable to distort the facts. No amount of preventable lead exposure is acceptable and shame on you for suggesting otherwise.

Your statement that lead “will periodically be washed (or blown) away defies logic and commonsense, and any concern for the rest of your communities population. Where does the lead go? To an adjoining swing set in a park,or a park neighbors bbq grill?

And, aren’t you in the Chesapeake Bay watershed?

Also, just how do you define a “significant health risk”? If it is your child that develops MRSA or cognitive decline due to that small bit of lead exposure, do you think your reaction will be “Gee, I’m glad those practices weren’t rained out?

I have a lot more I’d like to say, but I need to wrap up. You also missed the boat on MRSA.

Readily available studies have shown a numerical correlation between MRSA infections, and playing on artificial turf. Most experts seem to agree that the bacteria may not be being picked up from the fields themselves, but that the higher incidence of turf burns (also documented) on artificial turf fields provide an excellent opening for the bacteria to enter. And since MRSA is easily transmitted even kids who don’t play on turf are then at risk.

Also, I disagree that “the primary worry has been the ground up recycled tires…”. They are a legitimate worry that demands further study, but most parents I know worry most about excess heat on these fields. Does your club have an infrared thermometer installed at each field, and an ironclad policy that the fields are closed when the temperature hits a certain mark? If not, why not?

Maybe these fields are the greatest thing since sliced bread, but instead of disseminating half-truths, you owe it to the kids you claim to care about to demand more testing and research into these fields and the fiscal ramifications at replacement time before more are built.
I hope that you will do the right thing - make sure comprehensive studies take place now.

X Curmudgeon said...

Thanks you for your perspective. A long and thoughtful comment like that deserves a balanced response.

We agree that the CPSC should look into the issues that have been raised with respect to synthetic turf fields, using good science. In that manner, we would hope that concerned parents can get concrete answers to their questions.

We raised the issue of risks associated with grass fields for a reason: there is no free lunch. No activity is completely safe. Any examination of the risks and hazards of synthetic fields must be weighed against those associated with grass fields, which are quite real.

We agree that one hazard of synthetic fields is the high temperatures that can be reached on hot, sunny days, of which we get plenty in the summer here in Arlington. (Generally, it gets so unpleasant here in late summer afternoons that no one wants to play on a grass or a synthetic field; that said, warnings need to be posted about the heat hazard on a synthetic field, and they may need to be watered to cool them in certain conditions where play is nonetheless occurring.)

We also agree that any lead hazard needs to be abated. The point we're trying to make about lead, however, is that the mere presence of lead should not freak people out. The hazards of lead are pretty well known and defined. Health authorities need to establish just which fields pose a lead hazard, what the source of the lead is, what form it is in (if it's in inhalable dust on the field, that is a clear problem), and what the exposure level is. We don't criticize NJ officials for closing two fields with high lead levels. At the same time, responsible media need to point out that another 10 fields were tested with no elevated lead found, so it is likely that most synthetic playing fields don't pose this hazard.

On MRSA, we still think the data is sketchy. Getting proper controls for a good study is difficult. But we would advise players who get turf burns--as well as those who get scrapes on our grass fields, many of which are mostly dirt, to carefully disinfect and be wary of staph and any other infection.

We wouldn't go overboard and say synthetic fields have no risks. On balance, however, we are so far persuaded that the substantial benefits here in Arlington outweigh those risks. We hope that continued investigation of the potential hazards of artificial turf fields will help to better quantify that balance.

VAST said...

One thing not mentioned by Curmudgeon or by annoymous is the respiratory effects of the off-gassing. There are many instances of kids having to leave fields during the course of a game due to the overwhelming fumes coming off the crumb rubber. Kids with and without asthma have been having respiratory issues.

This product is not the "be all end all". It is dangerous for human health and also for the environment. It is imperative that there are some type of federal regulations imposed on this product, especially since small kids are the population that utilitzes it. Where has the common sense gone?

Vox Populi said...

Hi Curmudgeon:
Thanks for airing and informing this conversation. I may choose to air this conversation on, an "Advocate for Business (specially community and heart centered businesses) in NJ.

In broad terms, I would back away from the synthetic stuff on the following grounds:

1. While much money and water are wasted on grass, playing fields are about the best ways to use grass which should ideally be maintained without chemical fertilizers and the bare minimum of any pesticides (preferably none).

2. Since we cant really test for synergistic health effects, any substance which is toxic will be released sooner or later. Think of those cleats folks!

Last but not least, remember that the care and upkeep of grounds creates local employment, community and best of all the smell of frshly cut grass

Best regards and thanks to all who care enough about issues like this to air them~

X Curmudgeon said...

Thanks Vox. All things being equal, we'd rather play on a nicely maintained grass field any day! But in our tight urban community, a good grass field is hard to come by--the only way we can really maintain them is to limit play, and then we don't have anywhere to practice.

Yesterday, the Consumer Product Safety Commission issued a release on its investigation into lead pigments used in a small number of synthetic fields, concluding that those fields are still safe for children to play on. The release is here. You can find the release at:

Robin said...


thanks for the balanced approach. I live across the way in Montgomery County, where we are seeing a much slower approach (though with little more scientific analysis).

as a strong proponent of synthetics, the one area that I think we might need to look at again is heat. I run teams in NCSL, we play on artificial turf, and I do think we should have a clear policy in place for managing the temp issue - whether it's mandatory temp reduction measures after a certain point, or canceling play.

you can reach me through my email if you want to chat more about this - I'm interested in what's happened in the 2 years since your post.

X Curmudgeon said...

Thanks Robin--I certainly agree with you, especially this summer, that it can just get too hot on synthetic fields to play safely.

Of course, even grass fields--or more commonly around here, grass and dirt--can be dangerous on hot, humid days. Hydration is key, and coaches and parents have to be very careful, especially with younger kids who frequently aren't as aware of their bodies' needs.

In any event, in Arlington--and most of Northern Virginia--we're moving forward with more synthetic fields. We opened a new one at Thomas Jefferson Middle School a few weeks ago, and have three under construction at Long Bridge Park.

This winter was tough--synthetic fields are great in the cold, but they easily cover with snow and the field manufacturers discourage manual removal of the snow. We faced a crisis when our early March tournament, played entirely on synthetic fields, approached and we stil had a lot of snow around. We eventually persuaded authorities to let us manually shovel snow off many of them, which took many man/woman hours of intense aerobic activity!