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Introduction
Since the first human exploration of coastal Antarctica at
the end of the 19th century, disposal of faecal waste has
generally been into the sea (Meyer et al. 1963, McFeters
et al. 1993, Hughes 2003, Hughes & Blenkharn 2003). With
exploration inland, this method is not practical and most
human waste has been left in situ, either buried in snow
(Parker & Martel 2002) or discharged to inland streams and
lakes. Burial of human waste in ice pits is still common
practice for inland research stations, situated on ice shelves
or the polar plateau, and for both static and travelling field
parties. Once buried and maintained at low temperatures,
faecal waste in Antarctica undergoes relatively little
degradation and could become a long-term pollution
problem (Parker & Martell 2002).
The British Antarctic Survey (BAS) Fossil Bluff Field
Station is situated on Alexander Island beside George VI Ice
Shelf (Fig. 1). The base was constructed in February 1961
and occupied in the winters of 1961, 1962 and 1969–75,
after which time it has been operated as a summer-only
station. During the 1960s, all rubbish generated at Fossil
Bluff was deposited at a waste dump on the surface of the
ice shelf. After 40 years, the dump has remained on the
surface of the ice shelf and has not been buried by snow. It
was removed completely in 2003. Until recently, toilet
facilities at Fossil Bluff Field Station were primitive.
Initially, faeces were excreted directly into empty flour tins
and deposited on the dump. However, in the 1970s a
chemical toilet was installed and the waste was then
emptied into a nearby crevasse. Facilities to dispose of
human faecal waste were significantly improved in 2000
when BAS installed a propane-fuelled incinerating toilet at
the base.
This paper examined 30–40 year old human faecal waste
found at Fossil Bluff dump to determine the long-term
survival of faecal microorganisms in the Antarctic
Peninsula.
Materials and methods
Meteorology
Air temperature at Fossil Bluff Field Station was measured
every 6 h between January 1999 and December 2002 using
a platinum resistance thermometer (accuracy ±0.06°C; RS
Components, Corby, UK).
Microbiology
In February 2000, sealed flour tins containing faecal
material, and snow and ice from around the Fossil Bluff
waste dump were collected aseptically. Samples were
placed in insulated containers and flown to Rothera
Research Station (~ 1.5 h) for immediate analysis. During
the collection period the air temperature at Fossil Bluff was
+2°C. Other flour tins, opened at the site, revealed that at
that time the faecal material was unfrozen.
Faecal coliforms in melted snow (c. 1 l; melted overnight
at +4°C) were enumerated in triplicate using membrane
Antarctic Science 16 (3): 293–297 (2004) © Antarctic Science Ltd Printed in the UK DOI: 10.1017/S095410200400210X
293
Long-term survival of human faecal microorganisms on the
Antarctic Peninsula
KEVIN A. HUGHES*1and SIMON J. NOBBS2
1British Antarctic Survey, NERC, High Cross, Madingley Road, Cambridge CB3 0ET, UK
2Department of Microbiology, Plymouth Hospitals NHS Trust, Derriford Hospital, Plymouth PL6 8DH, UK
* Corresponding author: k.hughes@bas.ac.uk
Abstract: Human faecal waste has been discarded at inland Antarctic sites for over 100 years, but little is
known about the long-term survival of faecal microorganisms in the Antarctic terrestrial environment or the
environmental impact. This study identified viable faecal microorganisms in 30–40 year old human faeces
sampled from the waste dump at Fossil Bluff Field Station, Alexander Island, Antarctic Peninsula. Viable
aerobic and anaerobic bacteria were predominantly spore-forming varieties (Bacillus and Clostridium spp.).
Faecal coliform bacteria were not detected, indicating that they are less able to survive Antarctic
environmental conditions than spore-forming bacteria. In recent years, regional warming around the
Antarctic Peninsula has caused a decrease in permanent snow cover around nunataks and coastal regions. As
a result, previously buried toilet pits, depots and food dumps are now melting out and Antarctic Treaty
Parties face the legacy of waste dumped in the Antarctic terrestrial environment by earlier expeditions.
Previous faecal waste disposal on land may now start to produce detectable environmental pollution as well
as potential health and scientific problems.
Received 18 August 2003, accepted 26 April 2004
Key words: Antarctica, climate change, Environmental Protocol, faecal bacteria, faecal coliforms, freezing
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filtration (0.2 µm, Sartorius, Goettinger, Germany) on
membrane lauryl sulphate broth agar (MLSB; Oxoid,
Basingstoke, UK) according to established procedures
(Anon 1994). Immediately after opening the flour tins,
faecal samples (~1 g) were extracted from the centre of the
unfrozen mass under aseptic conditions, suspended in
300 ml of phosphate buffered saline (PBS; pH 7.2) and the
supernatant filtered as before to enumerate faecal coliforms.
The remaining flour tins were stored at -20°C and frozen
samples were transported to Derriford Hospital, Plymouth,
UK, for further microbiological analysis. Representative
portions of the faecal material were treated as described in
Table I, to culture a range of faecal bacteria (Public Health
Laboratory Service 1998a, 1998b, Roberts et al. 1995).
Examination for intestinal parasites was performed by
direct microscopic examination, and by the formol-ethyl
acetate concentration method (Public Health Laboratory
Service 1998c).
Results
Fossil Bluff experiences low precipitation and temperatures
and has been characterised as having a continental rather
than maritime climate (Harangozo et al. 1997). However,
Fossil Bluff experiences mean summer temperatures
(December–February) close to 0°C (Fig. 2) with regular
daily positive maxima, and is likely to experience higher
numbers of freeze/thaw events than at colder sites at higher
latitudes.
Faecal material sampled from the dump was not in a
frozen state upon collection indicating that this material
may have undergone repeated cycles of freeze/thaw over
the last 30–40 years. Preliminary microbiological
examination at Rothera Research Station of faecal material
and snow collected around Fossil Bluff dump did not reveal
the presence of viable faecal coliforms. The results of more
extensive microbiological examination of the faecal
material following freezing and transport to the UK are
shown in Table II. As shown initially, no coliforms were
isolated although these are normally common in faecal
material. Aerobic bacteria included Bacillus spp.
(B. pumilus, B. subtilis, B. licheniformis and B. sphaericus),
Aerococcus spp., Micrococcus spp. and Corynebacterium
spp. Viable alpha haemolytic Streptococci were also found.
Coliforms were not detected while Enterococci were
cultured in low numbers from only one sample [~1 ×102
colony forming units (cfu) g-1]. Anaerobic bacteria cultured
included Clostridium perfringens, which is a common
marker strain indicative of faecal contamination. Ova, cysts
and parasites were not seen in the faecal material.
294 KEVIN A. HUGHES& SIMON J. NOBBS
Fig, 1. Map of Fossil Bluff Field Station, showing the field station
and dump site.
Fig. 2. Air temperature data recorded at Fossil Bluff Research
Station. Plots represent mean (•; ±SD), maximum (∆) and
minimum (∇) monthly values over the period January
1999–December 2002.
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Discussion
This study has shown that faecal Enterococci and spore-
forming Bacillus and Clostridium species can survive in the
climatic conditions of the Antarctica Peninsula for 30–40
years. Under both aerobic and anaerobic conditions,
cultured bacteria were predominantly spore-forming
species, i.e. Bacillus spp. or C. perfringens. Gram negative
coliform bacteria were not cultured from the material, and
have been shown previously to be particularly susceptible to
damage by freeze-thaw stress (Parker & Martel 2002). Our
data are in agreement with work carried out by Meyer et al.
(1963) who examined human faecal material produced in
the first decade of the last century (50 years previously) by
Scott and Shackleton’s expeditions at McMurdo Sound,
continental Antarctica. They cultured Clostridium spp. and
Bacillus spp., but found no evidence of Escherichia coli or
other coliform bacteria. Nedwell et al. (1994) quantified
faecal bacteria in pony dung found at Scott’s camps at Cape
Evans dating from around the same period (1910–11). With
aerobic culture on Casein Peptone Starch Agar they found
SURVIVAL OF FAECAL MICROORGANISMS 295
Table I. Culture techniques for identification of faecal microorganisms.
Microorganism Growth medium Culture conditions: Enrichment and identification
oxygen, duration, temperature
aerobic colony count1Columbia blood agar aerobic, 44 h, 37°C Direct plating
Bacillus spp.1Polymyxin egg yolk mannite aerobic, 44 h, 37°C Bacillus spp. and other aerobic Gram positive
Bromothymol blue agar bacteria were identified using BBL Crystal
Gram Positive Identification System (Becton
Dickenson Ltd, Oxford)
anaerobic colony count1Fastidious anaerobic agar anaerobic, 44 h, 37°C Direct plating
Clostridium spp.2Fastidious anaerobic agar with neomycin anaerobic, 44 h, 37°C Direct plating
Clostridium perfringens2Perfringens TSC agar anaerobic, 44 h, 37°C Clostridium perfringens confirmed using API
Rapid 32A Identification System (Biomerieux
Ltd, Hampshire, UK)
Enterococci 1Azide dextrose broth by most probable aerobic, 44 h, 37°C Confirmation onto Kanamycin aesculin azide
number technique (MPN) agar, aerobic, 22 h, 44°C
coliform bacilli and Most probable number technique (MPN) aerobic, 44 h, 37°C
Escherichia coli (non-O157)1in minerals modified glutamate broth
Salmonella spp., Shigella spp.2Xylose lysine desoxycholate agar and aerobic, 22 h, 37°C Enrichment for Salmonella spp. in single
Hynes desoxycholate citrate agar strength selenite F broth, aerobic, 37°C, 24 h
Campylobacter spp.3Cefoperazone charcoal desoxycholate agar micro-aerophilic, Enrichment in Campylobacter broth, aerobic,
90 h, 42°C 37°C, 24 h
Escherichia coli 01572Cefixime-tellurite sorbitol MacConkey agar aerobic, 22 h, 37°C Direct plating
Vibrio spp.2Thiosulphate citrate bile sucrose agar aerobic, 22 h, 37°C Direct plating
Staphylococcus aureus2Baird Parker agar aerobic, 44 h, 37°C Direct plating
1Roberts et al. 1995 2Public Health Laboratory Services 1998a 3Public Health Laboratory Services 1998b
Table II. Counts of bacteria within Fossil Bluff dump faecal material
Microorganisms Sample Number
12 34 5
aerobic bacteria (cfu g-1) 4.8 ×1032.4 ×1077.5 ×1051.8 ×1045.0 ×106
Bacillus spp. (cfu g-1)+
a1.1 ×1031.2 ×1037.0 ×1021.0 ×102
anaerobic bacteria (cfu g-1) 6.0 ×1062.2 ×1053.2 ×1056.0 ×1046.0 ×105
Clostridium perfringens (cfu g-1)+
a1.7 ×1051.2 ×1022.5 ×1045.0 ×101
Enterococci (cfu g-1) 1.4 ×102nd nd nd nd
Coliform bacilli and Escherichia coli (non-0157) nd nd nd nd nd
Salmonella spp. (cfu 50 g-1)ndndndndnd
Shigella spp. (cfu 25 g-1)ndndndndnd
Campylobacter spp. (cfu 50 g-1)ndndndndnd
Escherichia coli 0157 (cfu 25 g-1)ndndndndnd
Vibrio spp. (cfu g-1)ndndndndnd
Staphylococcus aureus (cfu g-1)ndndndndnd
nd: not detected apresent in sample but not enumerated
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up to 1.9 ×106cfu g-1 pony dung, which upon further
examination were mainly Bacillus spp. Taking the data of
Meyer et al. into consideration, Nedwell et al. concluded
that coliforms can survive < 50 years and sporing bacteria
> 80 years in a continuously frozen state in Antarctica. From
our study, we can reduce the survival time of coliforms to
< 30 years and confirm the survival of sporing bacteria to be
> 30 years in the Antarctic Peninsula. Survival of aerobic
bacteria in 30–40 year old human faecal material from
Fossil Bluff ranged from 4.8 ×103to 2.4 ×107cfu g-1 [mean
= 6.0 ×106 (S.E. ±4.6 ×106)]. The mean value is lower than
found previously in older, though continuously frozen,
faecal material from McMurdo (2 ×107cfu g–1; 50 years
old) (Meyer et al. 1963). This difference may be a
consequence of the greater number of fluctuations around
freezing point experienced at Fossil Bluff compared to
McMurdo Sound (Harangozo et al. 1997, S. Colwell,
personal communication 2003), leading to increased
freeze/thaw damage to cells (Sanin et al. 1994, Parker et al.
2000) (Fig. 2). The finding that the faecal material at Fossil
Bluff was not frozen when initially collected from the dump
may corroborate this.
Bacillus spp. were found in Antarctic faecal material
examined by Meyer et al. (1963), Nedwell et al. (1994) and
in this study. However, Bacillus spp. are common
environmental isolates and despite careful sampling
protocols, may have come from other sources.
With the application of molecular biological techniques it
is now possible to detect DNA from human faecal
microorganisms in supposedly pristine Antarctic soils. For
example, Sjoling & Cowan (2000) found residual levels of
non-indigenous bacteria at abandoned Antarctic field camps
using PCR amplification of extracted soil DNA, though
Upton et al. (1997) failed to detect human commensals
using PCR around Halley Bay Research Station. Baker
et al. (2003) list a number of PCR primers for specific
microbial species, which could be used in pristine
environments to detect microorganisms indicative of human
impact. Whilst a major methodological advance, this
technique does not indicate whether the microorganisms are
viable, for which we have to rely on traditional culture
techniques for the foreseeable future.
Impact of regional climate change
Antarctic Treaty Parties face the legacy of waste dumped in
the Antarctic terrestrial environment by earlier expeditions.
Previous methods of human waste disposal on land are now
starting to produce detectable but localized environmental
pollution as well as potential health and scientific problems.
In some areas of the Antarctic Peninsula, regional warming
has caused a decrease in permanent snow cover around
nunataks and coastal regions (Fox & Cooper 1998) with the
result that previously buried toilet pits, depots and food
dumps are now melting out. At Sky Hi Nunataks
(P. Convey, personal communication 2003) and Witte
Nunataks (southern Antarctic Peninsula; M. Hunter,
personal communication 2003), faecal material was
encountered in 2001 by BAS field parties that may have
been derived from either dogs or humans in travelling
geological field parties dating back to the 1970s. Also,
buried faecal material on glacier surfaces are now being
rediscovered due to reduced annual snow accumulation, and
increased surface melt and ablation. For example, the
surface lowering of the ice ramp at Rothera Point, which
Smith et al. (1999) attributed to regional climate change,
has resulted in dog faeces (dating from before February
1994) coming to the surface through ice melt (Hughes,
personal observation 2001). As well having health and
safety implications, buried faecal material can cause other
practical problems: in January 2001 a BAS Twin Otter
aircraft, upon landing at Utopia Glacier, Alexander Island,
caught one of its skis in an unmarked old toilet pit that had
become partially exposed (Hughes, personal observation
2001).
Science implications
Scientists must select carefully their study sites to avoid
areas of previous human impact. Unfortunately, these sites
are often only poorly mapped, especially in remote field
locations and on the polar plateau. In the early 1970s, BAS
glaciologists working on the George VI Ice Shelf drilled an
ice core through some dog faeces left by an earlier
expedition (D. Peel, personal communication 2003). At
sites of unique scientific importance, the cumulative impact
of scientists working in the same place for many seasons
can have significant consequences. For example, ten
persons working for three summer seasons would produce
over 1000 kg of faecal waste. Under Annex III (waste
disposal and waste management) of the Environmental
Protocol the Treaty nations are required to ‘prepare an
inventory of locations of past activities (such as traverses,
fuel depots, field bases, crashed aircraft) as far as is
practicable, before the information is lost, so that such
locations can be taken into account in planning future
scientific programmes (such as snow chemistry, pollutants
in lichens, ice core drilling)’. However, even if adequately
carried out today, this does not provide information on the
burial of faecal waste over the past 100 years.
Conclusions
This study has shown that faecal Enterococci and spore-
forming aerobes and anaerobes present in 30–40 year old
human faeces have survived the climatic conditions of the
Antarctic Peninsula, including repeated freeze-thaw cycles.
Increased rates of snow and ice melt, possibly associated
with regional climate change, have resulted in previously
buried faecal material becoming exposed. Effective
296 KEVIN A. HUGHES& SIMON J. NOBBS
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implementation of the requirements of the Environmental
Protocol is therefore needed, as well as research and
development of alternative methods of human waste
disposal in inland areas of Antarctica.
Annex III of the Protocol on Environmental Protection to
the Antarctic Treaty (1991) requires that existing Antarctic
waste disposal sites are cleaned up. In the summer of
2002–03, BAS completely removed the waste dump at
Fossil Bluff (approximately 52 tonnes of waste) by Twin
Otter aircraft to Rothera Research Station, after which it
was transported by sea for recycling or safe disposal either
in the Falkland Islands or the United Kingdom (Plato 2001).
The results from this study were used to implement correct
and safe working practices for the removal of the faecal
material from the dump site: personnel were provided with
disposable safety clothing and washing facilities, and all
material associated with faecal material was treated as
biohazard waste.
Acknowledgements
This work was supported by the British Antarctic Survey’s
‘Biomolecular Responses to Environmental Stresses in the
Antarctic’ project and the Environment and Information
Division.
We thank Nigel Blenkharn for help with sample
collection, Steve Colwell for meteorological data and Pete
Marquis for logistical assistance. M. Hunter, D. Peel and R.
Mulvaney are thanked for historical information. P. Fretwell
is acknowledged for map preparation and Drs P. Convey
and J. Shears for comments on the manuscript. We thank the
referees, D. Cowan, D. Nedwell and L. Parker, for their
constructive help.
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