Results
Field Samples
The results
of total microbial populations
are shown in Table 1. While
microbes exist in the infill
media the number was low
compared to natural turfgrass
field soils. It should be
remembered that microbes
tend to be present on most
surfaces humans come in
contact with and the simple
presence of microbes should
not be cause for concern.
In fact, many products on
the market claim to boost
the microbial populations
of natural turfgrass soils
with higher microbial populations
considered to be beneficial.
| Table
1. ColonyTable 1. Colony
forming units (CFU)
detected on R2A media
per gram of crumb rubber.
|
Field
ID#1 |
Product |
CFU/g
crumb rubber |
1H
=sample collected from
higher use area of field
L = sample collected
from lower use area
of field *=sample
collected from indoor
field |
1H |
100%
Crumb Rubber |
20200 |
1L |
100%
Crumb Rubber |
32667 |
2H |
Crumb
Rubber - Sand Mix |
3533 |
2L |
Crumb
Rubber - Sand Mix |
133 |
3H |
Crumb
Rubber - Sand Mix |
3467 |
3L |
Crumb
Rubber - Sand Mix |
13133 |
4H |
100%
Crumb Rubber |
9467 |
4L |
100%
Crumb Rubber |
30267 |
5H |
Crumb
Rubber - Sand Mix |
18867 |
5L |
Crumb
Rubber - Sand Mix |
8333 |
6H |
Crumb
Rubber - Sand Mix |
267 |
6L |
Crumb
Rubber - Sand Mix |
28333 |
7H |
Crumb
Rubber - Sand Mix |
4800 |
7H |
Crumb
Rubber - Sand Mix |
4800 |
7L |
Crumb
Rubber - Sand Mix |
55333 |
8H |
Crumb
Rubber - Sand Mix |
4867 |
8L |
Crumb
Rubber - Sand Mix |
24133 |
9H |
100%
Crumb Rubber |
9800 |
9L |
100%
Crumb Rubber |
17867 |
10H* |
Crumb
Rubber - Sand Mix |
0 |
10L* |
Crumb
Rubber - Sand Mix |
67 |
11H |
Crumb
Rubber - Sand Mix |
33200 |
11L |
Crumb
Rubber - Sand Mix |
28000 |
12H |
100%
Crumb Rubber |
333 |
12L |
100%
Crumb Rubber |
800 |
13H |
100%
crumb rubber |
267 |
13L |
100%
Crumb Rubber |
67 |
14H |
100%
Crumb Rubber |
8267 |
15H |
Crumb
Rubber - Sand Mix |
8600 |
15L |
Crumb
Rubber - Sand Mix |
3867 |
16H* |
Crumb
Rubber - Sand Mix |
200 |
16L* |
Crumb
Rubber - Sand Mix |
0 |
17H |
Crumb
Rubber - Sand Mix |
0 |
17L |
Crumb
Rubber - Sand Mix |
7267 |
18H |
100%
Crumb Rubber |
5000 |
18L |
100%
Crumb Rubber |
5533 |
19H |
Crumb
Rubber - Sand Mix |
53067 |
19L |
Crumb
Rubber - Sand Mix |
80000 |
20H |
Crumb
Rubber - Sand Mix |
54333 |
20L |
Crumb
Rubber - Sand Mix |
8867 |
Native
Soil (silt loam) |
259500 |
Sand
Based Soil |
309500 |
Pile fiber
samples were also collected
from several fields. CFUs
for fiber samples range
from 200-2933 CFUs per fiber
sample (2 fibers approximately
1 cm long) indicating that
the fibers alone generally
exhibited lower microbial
populations compared to
the infill.
Microbial
colonies isolated from field
samples generally included
both fungi and bacteria.
Some fields had predominantly
one organism type while
other fields contained a
variety of organisms. In
order to positively identify
the presence of S. aureus,
three procedures were used.
No colonies isolated from
any crumb rubber or fiber
samples tested positive
for S. aureus via selective
media, gram stain or latex
agglutination tests.
Other Surfaces
Surfaces
other than athletic playing
surfaces were tested for
the presence of microbes
and S. aureus. These surfaces
are not granulated and thus
the results are listed in
Table 2 as total colony
number as opposed to CFU
per gram of granulated material.
| Table
2. Number of colonies
per swab detected on
R2A media from various
sources in public spaces
and an athletic training
facility. |
Source |
Colony
Number
|
| *Sampled
immediately after use |
| Public
Areas |
Computer
Mouse |
>600 |
Elavator
button |
155 |
Outside
Door Handle |
80 |
Computer
Keyboard |
33 |
| Athletic
Training Facility |
Cold
Pool |
24 |
Blocking
Pads* |
130 |
Sauna |
536 |
Football* |
142 |
Weight
Equipment 1* |
62 |
Weight
Equipment 2* |
414 |
Towel
Hamper |
103 |
Stretching
Table |
14 |
Used
Towels* |
29 |
Trash
Can For Drink Cups |
205 |
| Table
3. Surfaces that tested
positive (+) for S.
aureus colonies per
swab detected. |
Source |
Colony
Number |
| *Sampled
immediately after use |
| Public
Areas |
Human
Hands |
+ |
Human
Faces |
+ |
Computer
Mouse |
- |
Elavator
Button |
- |
Outside
Door Handle |
- |
Computer
Keyboard |
- |
| Athletic
Training Facility |
Natural
Turfgrass Playing
Field |
- |
Synthetic
Turf Playing Field |
- |
Cold
Pool |
- |
Blocking
Pads* |
+ |
Sauna |
- |
Football* |
- |
Weight
Equipment 1* |
+ |
Weight
Equipment 2* |
+ |
Towel
Hamper |
- |
Stretching
Table |
+ |
Used
Towels* |
+ |
Trash
can for drink cups |
- |
Microbial
colonies isolated from surfaces
included a mixture of fungi
and bacteria. Colonies from
the trash can were predominantly
fungi. While not specifically
identified, all colonies
from the sauna swab appeared
to be the same. S. aureus
was positively identified
from several samples including
towels, blocking pads, weight
equipment, and the stretching
table. In addition, S. aureus
was positively identified
from every facial and hand
swabs tested.
|