Recently, my daughter's daycare installed a playground using recycled
tire chips as their ground cover material. Unfortunatly, the company they
purchased the tire chips from brought the wrong stuff. The tires they
delivered had not been decontaminated. The kids had been using this
lot, with contaminated tire chips, for several weeks before the tire
chips were replaced with clean ones. Daily, these kids would be picked up
covered in almost black dirt from the tires. The daycare seems to be
less than concerned - I don't know if they understand what was on
their playground. My question is should I contact someone (lawyers,
medical, the tire company, other parents) about the children's
possible exposure to asbestos? How much can be done for their health
at this point or am I just being paranoid about this whole situation?

Hi tmwm –

Well, I can certainly understand your concern. Seeing your little girl
come home from daycare covered in scary black grime, and then finding
out that the wrong ground cover was put on the playground would
certainly be unnerving.

Well, I hope to put your mind at ease here, with the obvious caveat
that I am not a doctor, nor am I a toxicologist or chemist. I am a
researcher and will provide you with all of the related information
that I can find. If, after reading what I’ve told you here, you still
aren’t comfortable with the situation, I would encourage you to talk
to your daughter’s doctor about the possible effects of exposure to
untreated rubber tire chips.

First of all, I can find no link between asbestos and tires, shredded
or otherwise. Asbestos is not a component of tires and therefore would
not be something that your child would have been exposed to in playing
in untreated tire chips. This table lists the typical types of
materials used to manufacture tires.
 

Typical Composition of a Tire


Synthetic Rubber
Natural Rubber 
Sulfur and sulfur compounds 
Silica
Phenolic resin 
Oil: aromatic, naphthenic, paraffinic 
Fabric: Polyester, Nylon, Etc. 
Petroleum waxes 
Pigments: zinc oxide, titanium dioxide, etc. 
Carbon black 
Fatty acids 
Inert materials 
Steel Wire 


Passenger Tire – composition by weight

Natural rubber        14 % 
Synthetic rubber      27% 
Carbon black            28% 
Steel 14 -                  15% 
Fabric, fillers, accelerators, antiozonants, etc.      16 - 17% 
Average weight: New 25 lbs, Scrap 20 lbs. 

http://www.rma.org/scraptires/characteristics.html


Even if asbestos were a component of tires, and present in the
playground, asbestosis only occurs as a result of long-tem daily
exposure to the loose fibers. Two weeks of short-term exposure is not
a health issue.

http://www.hhs.gov/news/press/2001pres/20010916a.html


Now, to understand what your daughter may actually have been exposed
to, we need to understand what the difference is between untreated
tire chips and processed or treated tire chips.  From what I have
read, there is very little difference between the two. In short, the
treatment process focuses on two things:

1)Removal of the “hard” components of the tire – primarily steel wire
2)Washing, then sealing or coating with colorant to prevent that messy
black dust from getting all over children. The dust is a naturally
occurring byproduct resulting from the breakdown of the rubber. It is
not considered to be toxic.

These are excerpts from various websites that describe the process
that tire chips go through before being used on playgrounds.

“Manufacturing of crumb rubber and the use of tire chips as a
substitute for playground gravel requires the tires to be shredded and
magnetic separators be used to remove all steel fragments.  In
addition to removal of steel beads, several recycling applications
require other modifications to the tire, such as, removal of polyester
fragments and colorizing the rubber material.”

http://www.ciwmb.ca.gov/Publications/Tires/43296029.doc



Playsafer 1/2 inch chips are smaller than most others. The smaller the
chips, the less likely they are to contain embedded steel wire. To
ensure that all wire is removed, Playsafer chips pass through 4
unique, state of the art magnets during the manufacturing process.
This extra attention literally ensures no steel content. In fact,
Playsafer is guaranteed to be 99.9% steel-free.

http://www.rubberecycle.com/playsafer.htm


In order to prevent foreign objects to contaminate the product, the
manufacturing process includes passing all ground rubber over
industrial magnets designed to remove all magnetic particles (wire,
nails). Furthermore, during processing the rubber pieces are
physically handled and inspected at various intervals, making it
highly unlikely that foreign objects pass undetected into the final
product bin.

http://www.homestead.com/prosites-closetheloop/guarantee.html


Pyrolysis, nature's way of breaking down any exposed surface, will
cause rubber "dust" to develop. Surfaces should be cleaned (rinsed
with water) routinely to prevent the dust build up. Colored (sealed)
rubber mulch resists discoloration and the chemical decomposition
caused by the hot sun.

http://www.homestead.com/prosites-closetheloop/guarantee.html


Disadvanatges [of using tire chips]:
---Unless treated, may cause soiling of clothing.
---May contain steel wires from steel belted tires.

http://www.homestead.com/prosites-closetheloop/guarantee.html


In all of my searching I could find nothing that discusses any health
hazards of being exposed to untreated tire chips. In fact, although I
certainly wouldn’t recommend testing it, some sites indicated that
tire-rubber is so inert that, if accidentally ingested by a child, it
would pass unscathed through the digestive tract and do no harm to the
child.

This report pretty well sums up the exposure hazards:


“Uncontaminated whole scrap tires or tire shreds are considered
non-hazardous inert materials [CRWQCB, 1998].  Thus, the material
should have no health effects or impacts on humans.  Employees, who
have prolonged contact with whole tires or tire shreds, however,
should practice good personal hygiene by frequent washing of hands and
arms with soap and water.”

http://www.ciwmb.ca.gov/Rulemaking/Monofill/RptBody.doc


The only time tire rubber is considered to be toxic is when it is
being burned. Then it gives off toxic fumes and smoke. Obviously this
isn’t an issue in your case.


So, I think you can stand down in your alert. In my opinion there is
no need to raise an alarm with parents or involve lawyers in a
confrontation.

If you are still worried, what you could do is ask the daycare to
provide you with the name and number of the company that sold them the
processed tire chips. Then contact that company and ask them exactly
what procedure they use to “purify” their chips. If all they have done
is take out the wire and coated the chips for cleanliness purposes,
then you can rest assured that your daughter was exposed to nothing
more than a messy  “Liquid Tide” moment.

If anything I’ve said isn’t clear, please feel free to ask for
clarification.

I wish you the best –

K~

Search terms:

Tire chips playground toxins
Tire chips playground health hazards
Tire chip processing
Rubber tire components
Tires asbestos
Asbestos short-term exposure 
Tire chip dust toxicity

---

Request for Answer Clarification by tmwm-ga on 12 Sep 2002 12:33 PDT

So it's unlikely that the dust from asbestos brakes would be the dust
she was picking up from the tires.

---

Clarification of Answer by knowledge_seeker-ga on 12 Sep 2002 14:18 PDT

Hi again tmwm,

I’m hesitant to give you a pat assurance that there was NO asbestos
from brake drum linings mixed in with the tire chips on your
playground. Naturally, there is a chance that brake lining dust could
get on a tire before a tire is removed from the car. And that tire
could end up being shredded into chips for playground usage without
being washed off first if it wasn’t processed properly. But, since
we’re talking probabilities now, I’d feel safe in saying the chances
are low that this would occur.

The website below describes the process for converting whole tires
into tire chips or crumb rubber. Although possible, it doesn’t seem
likely that any asbestos dust that was originally on a tire would
remain throughout the process:

http://www.tfhrc.gov/hnr20/recycle/waste/st1.htm

Also remember, that one method of asbestos dust control is simply to
use water. Auto mechanics are urged to wash down brakes, tires, and
work areas with water to prevent any potential asbestos fibers from
becoming airborne. Most tires, once they are removed from a car, are
stacked outdoors, sometimes for months or even years, until they are
collected by recyclers. These tires are exposed to rain which would
effectively was away any asbestos dust. The same would hold true of
the chips, which are also stored outdoors in large piles. By the time
these chips get to your playground they’ve probably been rained on
plenty of times.

So, in conclusion, I would say that the dust your daughter was exposed
to was UNLIKELY to contain asbestos. More likely it was just the dust
from the decomposition of the rubber itself.

I hope this puts your mind at ease. Again, if you’re still concerned,
please talk to your child’s doctor.

--K~

Thanks K! I appreciate your answer and confidence