Download - Michael Ells - Surface disposal
Exit Strategies Conference
Smearing asa Method of Feces
Disposal +PublicHealth
Impacts
Mike EllsProfessorEmeritus
Ferris StateUniversityBig Rapids,Michigan
The Public Health Impacts of Surface Disposal as a
Method of Feces Disposal in Alpine, Temperate Forest and Arid Environments
Michael D. Ells, RS, MSPH, DAASProfessor Emeritus
Environmental Health and Safety Mgmt.
Ferris State University
History…1995 – Study of surface water runoff in the Muir Snowfield, Mt. Rainier National Park.
1999 – Study of Smearing on rocks in Fell Fields within the Muir Snowfield.
2000 – Study of Smearing on rocks in a Temperate Forest and in an Arid Environment.
1995 The Muir Snowfield
Study Site
Climbers, et alCamp Muir10,200’
9,400’
8,200’
History... 1995 – Since the urine from the Solar Toilets at Camp Muir is released to the underdrain of the snowfield, MORA wanted to know if surface water within the snowfield was contaminated with this discharge.
A study the fecal microorganism, chloride and TDS content of runoff from the snowfield was completed.
I found NONE!The question then became…
Where did “IT” go?
Predicted FlowpathAnalysis (GIS)indicate that we may havebeen samplingin the WRONGAREA!
When the “urge” Strikes!Feces in the Middle of the Trail toCamp Muir,
22 May
Two DaysLater theTrail hadMoved to“Accommodate”the Pile!
24 May
1995 ...At about this same time NOLS began suggesting surface disposal (smearing) as a method of human waste “disposal.”
History ...Additionally, there was no Public Health data to support this practice.
The 1999 Project Had Two Parts...
Part 1: What happens to feces and fecal microorganisms deposited in snow in the Alpine Environment...
Part 2: The Public Health Impact of Smearing as a Human Waste Disposal Alternative in the Alpine Environment.
Part 1...6 Specimens were set out on 3 June 1999.
2 “Deep” specimens2 “Steep” specimens2 “Flat” Specimens
Deep Specimens...
The objective was to sample snows beneath the feces to determine the downward migration of fecal microorganisms.
Steep Specimens...
The objective here was to determine the rate and extent of down slope migration of fecal microorganisms on a steep snowfield surface.
Flat Specimens...
The objective here was to determine the rate and extent of migrations of fecal microorganisms on a flat snowfield surface.
Deep-12 June 1999
Note migration
of color fromfecal
specimen
Deep 2, June 3, 1999, Closer (sorry)…Note Staining
18 Days of Exposure
Note the “Gray” area circled. Evidence of significant desiccation.
SNOWFALL BURY’S SAMPLES…
A snowfall in early July buried the samples and we had to re-establish the 6 samples.
All 1995 data was taken from the 6 new samples.
Sample Collection...
Samples were generally collected late morning or early afternoon.
Analysis...
Samples were analyzed 24 hours following collection.
Plates were counted 24, 48, or 72 hours later : (FC, E.c.), (FS), and (P.a.)
Findings...
Fecal bacteria are washed off to the surrounding snow or ice.
This does not appear to last long nor are the numbers high.
Snow Surface
D-1 D-2
6”
12”FC FS14 34
FC FS22 640
FC FS34 8
8/1/99
8/29/99
8/1/99
Downward Migration of Fecal Coliform and Fecal Streptococci
Aerial (Overhead) view of
S-2 Specimen (FC, FS)(8/29/99 - 41 Days of Exposure)
ND, ND
ND, ND
ND, ND
ND, ND
ND, ND
All Locations, All Dates = ND FC, FS, E.d., and P.a.
INTERPRETATION: % Slope has no effect on the migration of fecal microorganisms!
Aerial (Overhead) view of S-2 Specimen
(Fecal coliform, Fecal streptococci)(8/29/99 - 41 Days of Exposure)
ND, ND
ND, ND
ND, ND
ND, ND
ND, ND
All Locations, All Dates = ND FC, FS, E.c., and P.a.ADDITIONAL INTERPRETATION: Wind plays little
tono role in the translocation of fecal
microorganisms!
Aerial (Overhead) view ofF-1 Specimen (FC, FS)
(8/29/99 - 41 Days of Exposure)Upslope
Downslope
Left Right6”12” ND, NDND, ND
ND, 2
ND, ND
ND, ND
Fecal Organisms in Feces vs Exposure TimeF-2 (Surface Specimen)
1101001000100001000001000000100000001000000001000000000
7/20/99
7/27/99
8/3/99
8/10/99
8/17/99
8/24/99
8/31/99
9/7/99
Date
Log
of S
urvi
ving
Mic
roor
gani
sms
FCFSEc
Organisms in Feces vs Exposure Time
D-1 (Internal Specimen)
1
10
100
1,000
10,000
100,000
1,000,000
10,000,000
Date
Log
of S
urvi
ving
Mic
roor
gani
sms
FCFS
Findings...Fecal Streptococci have a tendency to survive somewhat longer than do Fecal Coliform’s and Escherichia coli.
Findings...
Flora deep within a fecal specimen survive longer, decreasing at an average of one order of magnitude per 3 or 4 weeks.
Findings...Fecal Microorganisms can survive in the alpine environment.
Surface Flora Decrease Significantly over time and average one order of magnitude per week.
Findings...Feces deposited on snow has a tendency to act as a black body and sink into the snow.
Specimens never completely disappeared... (unless covered by new snow!)
S-21 August
2 Pieces BrokenOff
S-215 August
Specimen hasBroken into3 Pieces
S-212 September
Specimen hasBroken into> 12 SeparatePieces
Part 2...
The Smearing project began on 6 July 1999 when 4 smears were established in a fell field at 8,200’
TK-1 Smearing Site Prep 6 July
4 Flat Rocks were first weighed,
then smeared
with a “pancake/veneer” of fresh fecal material.
Smears...Two “Thin” Smears: approximately 2-3 mm thick. TN-1 and TN-2.
Two “Thick”Smears: approximately 4-7 mm thick. TK-1 and TK-2.
TN-1 Twenty Minutes Post Smearing
TN-1 Twenty Minutes Post Smearing - Close Up
TK-2, 20 July 1999. Note desiccation
and wasting (on left edge of smear)Two Weeks of Exposure
TK-2 40 Days of exposure
NOTE: DriedSmear MassTo the BottomLeft of Rock
TK-254 Days of Exposure
Hard to Seebut Dried SmearMass hasDisappeared.
TN-131 Days of Exposure
Rock appearsto have almostbeen WASHEDclean!Smear Flakes visible below + undigested corn.
Loss of Smear Material...Smear desiccation averaged 84.4% of their Mass
Low loss = 77.6%High loss = 95.3%Exposure time was 56 days (8 weeks)
Weight Loss of Smears, 1999
05
101520253035404550
6 July 1 August 15 August 12 September
Date
Gra
ms
of F
eces
TN-1 Tn-2 TK-1 TK-2
68 Days Exposure Time
Weight Change Past This Date Seemed tobe More a Function of Rain/Snow
Fecal Organisms in Feces vs Exposure TimeTK-1 (Smear Specimen)
110
100
1000
10000100000
1000000
10000000
100000000
Jul-99 Aug-99 Sep-99
Date
Log
of S
urvi
ving
Mic
roor
gani
sms
FCFSEc
Findings...
Smears begin desiccating immediately and virtually disappear within 8 weeks of exposure.
Findings...Soils surrounding the smears do not become significantly contaminated with bacteria washed from the smears or smear contaminated rocks.
Interpretation...
Organisms succumb to the environmental conditions prior to the breakup and flaking off of the fecal mass.
So What Are the Public Health
Impacts?
Public Health Impacts...Viruses probably do not survive any longer than the bacteria.
Protozoa may survive LONG after bacteria.
Recommendations...Continue study to verify 1999 results.
Add Temperate Rainforest Component.
Add Dry Climate Component (Eastern Washington Site)
Investigate the possibility of including Protozoa.
2000 Study
2000 Study…2 Study SitesMt. Rainier National Park @ Longmire, WA: 7 miles inside the SW entrance to Mount Rainier National Park.
Wet, Humid, Shady, Heavily Forested
Longmire Site Location Map
Longmire
Area Rainfall = 60-140” year-1
Longmire Study Area Site Map
Nisqually River
Longmire Site
Arid Site…Naches, WA: 10 miles on USFS Road 1400 off HWY 12 (this truly is 10 miles of bad road!)
Hot, Dry, Sagebrush and Ponderosa Pine. Open.
Naches Site Location
Map
X
XStudy SiteLocation
Naches Site Location
2000 Protocol Changes…Feces smeared rocks were placed in dog crates covered with ¼” hardware cloth.
Rational…I wanted to be certain that the disappearance was not due to coprophagous (feces eating) animals.
2000 Protocol Changes…
Within each crate, two Thick Smears and Two Thin Smears were placed
Samples for microbiological analysis were only taken from 1 Thin and 1 Thick Smear at each site during the study.
Rational…I wanted to be certain that weight loss was due to natural causes and not specimen collection.
Placing the Smeared Rocks in the Dog Crate
Smears Sampled:
N-TN2N-TK1L-TN2L-TK1
Smears Undisturbed
N-TN1N-TK2L-TN1L-TK2
MicrobiologicalExamination
Smear DesiccationExamination
Data Collection DatesSamples were set out on 3 June 2000.
Biweekly weights and fecal samples taken for analysis.
Final microbiology samples taken on 8/9 September 2000: 14 weeks (97 days)
Final data (weight) was taken on 6 October 2000: 18 Weeks (125 days)
Exposure Period…This exposure period was 10 weeks longer than the 1999 Alpine Experiment.
Rocks at both sites were tare weighed
A fresh fecal smear was applied to each rock
N-TK2
L-TK1
Drying evident from thevisible cracking.
Drying less evident -Smear infested withinsect larvae.
Naches Site
Longmire Site
Day 2
On 8 June, following 5 Days of Exposureand a rainstorm. L-TK2
07/02/2000(4 weeks)
Naches SiteN-TN1
Longmire SiteL-TN1
07/15/2000(6 weeks)
Naches SiteN-TN2
Longmire SiteL-TN1
09/08/2000(12.5 Weeks)Naches Site
N-TN1
Longmire SiteL-TK1
Lens Cover Problem!
Funky Mold Growthfollowing a rain.
White Stalks and Dots are Mold Hyphae and Sporangia on L-TN1,
6 October 2000
10/06/2000(18 weeks)Naches Site
N-TK1
Same (N-TK1)Close-up
10/06/2000
Longmire SiteL-TK1
Results…
Smear Desiccation…NachesN-TN2 lost 92.9% of its weight.
N-TK1 lost 97.3% of its weightLongmireL-TN2 lost 94.4% of its weight.
L-TK1 lost 87.7% of its weight
Fecal Weight Loss vs Time
05
1015202530354045
Sample Dates
Wei
ght o
f Fec
al S
mea
r in
Gra
ms
N-TN-2 L-TN-2 N-TK-1 L-TK-1
Rain in Longmire
Smear appearances were dramatically
different!
Naches Appearance…Dry Sponge-likeFibrous
Weight = 2.0 grams!
Longmire Appearance…FlatNon-fibrous
Longmire
Because the majority of the rocks still supported some remnants of the original fecal smears, the disappearance of the smears in the 1999 Alpine Study was probably aided by Coprophagous animals.
Soil Contamination…
Initial samples of soils from both sites were free of fecal bacteria contamination.
Soil Contamination…One type of fecal bacterium was found beneath one Naches smear, one time.
30 Fecal Streptococci were detected on 10 August.
Soil Contamination…Fecal bacteria were detected beneath both Longmire smears on 3 of 7 sample dates following smearing.
Numbers were highest on 17 June after 2 weeks.
Soil Contamination…
Numbers decreased as the study progressed.
None were found after 27 August beneath L-TK1 or after 10 August beneath L-TN2.
Soil Contamination…Numbers fluctuated from 700’s to 30 to zero to 60 and to zero again.
Fecal Coliforms Contaminating Soil Beneath Rocks Smeared with Feces
0100200300400500600700800900
Sample Date
Num
ber
of F
ecal
Col
iform
s pe
r G
ram
of S
oil
N-TN-2 N-TK-1 L-TN-2 L-TK-1
Red Lines = NachesBlack Lines = Longmire
Fecal Streptocci Contaminating Soils Beneath Rocks Smeared with Feces
0
2000
4000
6000
8000
10000
12000
6/3/20
00
6/17/2
000
7/1/20
00
7/15/2
000
7/29/2
000
8/12/2
000
8/26/2
000
Sample Date
Num
ber
of F
ecal
Str
epto
cocc
i per
G
ram
of S
oil
N-TN-2 N-TK-1 L-TN-2 L-TK-1
Red Lines = NachesBlack Lines = Longmire
Escherichia coli Contaminating Soils Beneath Rocks Smeared with
Feces
050
100150200
Sample Date
Feca
l Bac
teria
per
gr
am o
f soi
l
N-TN2 L-TN2 L-TK1
Red Lines = NachesBlack Lines = Longmire
Survival in Soils…E. coli does not survive well in soils.
FC survives more than E. coli but less than FS.
This has been demonstrated in past studies.
Organism Survival inside Fecal Smears
Naches vs Longmire
THIN SMEARS
0500000
10000001500000200000025000003000000
Initial 2-Jul 30-Jul
27-Aug
Sample Date
Fecal Bacteria Survival in L-TN1
FC FS Ec Pa
Bact
eria
per
gra
m
Fecal Bacteria Survival in N-TN1
050000
100000150000200000250000300000
6/3/20
01
6/17/2
001
7/1/20
01
7/15/2
001
7/29/2
001
8/12/2
001
8/26/2
001
Sample Date
Bac
teria
per
gra
m
FC FS Ec
Fecal Bacteria SurvivalIn Fecal SmearsL-TN1 vs N-TN1
Ps. Aeruginosa wasnot detected eveninitially so we gave uplooking for it.
Naches…Fecal bacteria succumbed quickly and populations fell to low levels.
FC were never again detected after the initial smear.
Naches…FS detected through 8 September at 235 gram-1 (but fluctuated from 45 to that number)
E.c detected one time following initial smearing, on 17 July at 225 gram-1
Longmire…Substantial survival throughout the entire study.
At the end of the study there were the following populations …
FC: 384,180 gram- 1
FS: 706,050 gram-1
Ec: 436,090 gram-1
1 2 3 4 5 6 7 8FC
ECFC
Ec
0500000
1000000150000020000002500000
Bacteria per gram
Sample Date
Organism
Bacterial Survival in N-TN1 vs L-TN1
FC FS EC FC FS Ec
Back row L-TN1
Front row N-TN1
Naches vs Longmire
THICK SMEARS
Bacterial Content
Naches…FC varied during sampling from 0 to 311,000+
FS levels fell much more slowly but eventually fell to zero.
Ec levels fell, rose and then fell to zero.
Longmire…FC increased by a factor of 7X initially. This may have been due to an unequal level of FC’s within each gram of fecal material.
Longmire…FS levels fell rather consistently but were still at nearly 1,500 g-1 before the smear remnant disappeared.
E.c. levels fell 90% in two weeks then to zero for the remainder of the study period.
05000000
100000001500000020000000
Initial 2-Jul 30-Jul
27-Aug
Sample Date
Fecal Bacteria Survival in L-TK2
FC FS Ec PaFecal Bacteria Survival in N-TK2
0100000200000300000400000500000
6/3/2001
6/17/2001
7/1/2001
7/15/2001
7/29/2001
8/12/2001
8/26/2001
Sample Date
Bac
teria
per
gra
m
FC FS Ec
Fecal Bacteria SurvivalIn Fecal SmearsL-TK2 vs N-TK2
1 2 3 4 5 6 7 8FC
EcFC
Ec
0
5000000
10000000
15000000
Bacteria per gram
Sample Date
Organism
Bacterial Survival in N-TK2 vs L-TK2
FC FS Ec FC FS Ec
Front 3 Rows N-TK2
Back 3 Rows L-TK2
Overall Conclusions…
All smears lost between 88% - 97% of their weight.
There were major differences in the appearance and “consistency” of the smear remnants.
Overall Conclusions…
Organisms in the Naches smears experienced a much more rapid and more complete die-off than the Longmire smears.
Overall Conclusions…
Organism survival was affected by Temperature, Humidity and Solar Radiation exposure.
Overall Conclusions…Fecal organisms contaminated the soils beneath only one of the Naches smears (FS) and then only 30 cfu’s.
This was probably due to higher heat, more exposure to solar radiation, little or no rain, coarse, sandy soils and to the initially high rate of desiccation.
Overall Conclusions…Soils beneath both Longmire soils became contaminated more quickly and to higher levels.
This was probably due to rainfall.Their survival in the soil for a longer period of time is probably due to more shade, lower temperatures, increased humidity, and the organic (humus) nature of the soil.
Rainfall was noted during the first three days of smear exposure at Longmire with stained water running off from the fecal smear.
This probably increased the fecal organism runoff.
Public Health Impacts
It was not the intent to test for Viruses, Protozoa or Helminthes.
Since viruses can survive at least as long as bacteria,
and since Protozoa can survive even longer…
Smearing feces on rocks as a method of “disposal” may, under some environmental conditions, have a tendency to build up not only fecal bacteria but probably viruses and protozoa as well in the “disposal” area.
Bacteria could be spread to surface water by rain or spread by animals.
This could potentially lead to the spread of human pathogens.
Smearing would tend to expose the feces and the seeds within, to animals which could then spread them to areas as non-indigenous or exotic species.
Another Consideration…
Smearing seems to be a deceptively simple method of “disposal.”
Much more study needs to be conducted on how quickly fecal organisms would build up in an area where multiple (100’s or 1000’s?) of people would use the area frequently during a season.
Smearing should only be considered in either alpine or very arid areas and under very strictly controlled circumstances.
Ideally, the use of plastic bags to retrieve feces and pack it out is a preferred method from both a Public Health and an Environmental perspective.
My OPINION…
We still have a lot to learn about how fecal organisms behave in the environment.
There was also a third project in 2000!
Since fecal masses deposited onsnow (whole) disappeared…Would the same thing happen tofecal smears on snow?
This experiment consisted of smearing feces on the Muir Snowfield…
and then sampling surrounding snows and feces until September
Smearing took place on 29 July, 2000.
If you don’t want to look…
TURN AWAY!
We tried Smearing with a Snowball
It didn’t work too well because the Feces kept sticking to the snow and was difficult to spread.
We tried smearing with a PlasticZiploc® Bag as a glove.
Plastic Bags work better!We sampled snow immediately following smearing.
020000400006000080000
100000
Bacteria per ml of melted snow
FC FS Ec Ps.a
Fecal Organism
Levels of Fecal Bacteria in Stained Snow
FCFSEcPs.a
66,000 FC90,000 Ec
Two Weeks Later…Snow Samples 08/11/00No Detectable Fecal Bacteria in samples of 10, 25, 50 ml of melted snow!
Following August 11, the samples disappeared! (that’s just 2 weeks!)
Conclusions…We need to take micro samples ~hourly over a several day period of time to determine the length and extent of migration of fecal organisms.
Conclusions…Fecal smears disappear more quickly than fecal masses on the snowfield.
This disappearance and low fecal contamination levels may be due to the environmental conditions,
And/or coprophagus animals!
Conclusions…Smearing may be a better method of “disposal” on snow in the alpine environment than simply dropping feces on snow or burying it.
Special Thanks tothe Funders and Supporters of this
Project!
1995 Study Report
1999 Study Report
2000 Study Report(Arid
Environment)
2000 Study Report(Temperate
Environment)
QUESTIONS ?