4. Careless frostbite and unpreventable frostbite

It is the first experience for almost all doctors to visit Antarctica. They are confused by the difference of medicine between Antarctic environment and the daily site. However, if it is possible to predict the diseases which may occur and the time of onset, doctors can prepare themselves and take preventive measures.

For that purpose, an analysis was done on the medical consultations of participants at Syowa Station during the first to 43rd wintering over (from 1956 to 2003). The total number of wintering-over participants was 1278; 4931 medical cases occurred during this period. Among them, 4633 cases in which the month of onset was clear were used to analyse rates of incidence by month.

In the analysis of each year, there are limitations in seeing the original tendency because the number of cases is small, and circumstances unique to each year may exert influence. Aggregation over 40 years eliminates these problems.

Figure 7 shows numbers of monthly consultations. The cases increase at the start of overwintering and sharply drop during the polar night. Thereafter, the rate shows a gradual decreasing trend with no particularly notable changes.

Frostbite increases and peaks in May (Figure 8). This coincides with late autumn which is not the coldest season of Antarctica, experiencing temperatures of 15 to 20°C (rarely experienced in Japan) that drop rapidly. Such an increase in frostbite incidence may be due to carelessness and unpreparedness.

#### Figure 7.

Monthly evolution of all 4633 cases recorded from 1956 to 2003. The total number of medical consultations at Syowa Station was 4931 cases from 1956 to 2003. Among them, 4633 cases of with known onset month were analysed. There is no particular seasonal variation, but the cases frequently occur at the start of overwintering, and there is a gradual decreasing trend thereafter.

(Figure 9). Environmental factors such as coldness and dryness contribute to these diseases, and the viruses that are the biggest causes of these illnesses in Japan may also be the culprits here. However, there are no viruses which naturally occur in the harsh environment of Antarctica, and it is hard for viruses brought in by humans to survive among the small isolated group of station occupants once the people

A cold outbreak on the Icebreaker ship and at Syowa Station after the ship's arrival. The number of newly coldaffected people is shown by period: early (e-), middle (m-), and late (l-) in each month. Groups include "ship crews" and "JARE 40", who were new expedition members arriving from Japan on the ship as part of the 40th expedition. Members of the JARE 39th expedition were divided into three groups when the ship arrived at the station: 25 members were at the station; 6 members were at Dome Fuji base, returning to the station back in

January; and 8 members were absent on meteorite survey inland and came back in February.

Monthly occurrence of respiratory diseases. There were 218 cases of respiratory diseases from 1956 to 1999. They tend to occur at the beginning of overwintering and then decrease gradually before soaring in December.

Figure 9.

Human Beings in Antarctica

DOI: http://dx.doi.org/10.5772/intechopen.81974

Figure 10.

111

#### Figure 8.

Monthly occurrences of frostbite. A total of 321 cases of frostbite occurred from 1956 to 1999. In the aggregate, incidence peaks twice: the highest in May and the second in September, during the coldest season.

Subsequently, in the polar night season, frostbite cases decrease because outdoor work is restricted.

August and September are the coldest months with temperatures of nearly 40°C. In addition, outdoor activities come into full swing. Frostbite case increases again, reaching a second lower peak that does not exceed the first. Frostbite is considered unpreventable because these cases still occur despite awareness policies and preventive measures.

## 5. Viruses in closed populations always require the next new population to survive

According to the same aggregate data, respiratory diseases totalled 218 cases, including instances of the common cold and upper respiratory inflammation

Human Beings in Antarctica DOI: http://dx.doi.org/10.5772/intechopen.81974

#### Figure 9.

Monthly occurrence of respiratory diseases. There were 218 cases of respiratory diseases from 1956 to 1999. They tend to occur at the beginning of overwintering and then decrease gradually before soaring in December.

(Figure 9). Environmental factors such as coldness and dryness contribute to these diseases, and the viruses that are the biggest causes of these illnesses in Japan may also be the culprits here. However, there are no viruses which naturally occur in the harsh environment of Antarctica, and it is hard for viruses brought in by humans to survive among the small isolated group of station occupants once the people

#### Figure 10.

Subsequently, in the polar night season, frostbite cases decrease because outdoor

Monthly occurrences of frostbite. A total of 321 cases of frostbite occurred from 1956 to 1999. In the aggregate,

incidence peaks twice: the highest in May and the second in September, during the coldest season.

Monthly evolution of all 4633 cases recorded from 1956 to 2003. The total number of medical consultations at Syowa Station was 4931 cases from 1956 to 2003. Among them, 4633 cases of with known onset month were analysed. There is no particular seasonal variation, but the cases frequently occur at the start of overwintering,

August and September are the coldest months with temperatures of nearly 40°C. In addition, outdoor activities come into full swing. Frostbite case increases again, reaching a second lower peak that does not exceed the first. Frostbite is considered unpreventable because these cases still occur despite awareness policies

According to the same aggregate data, respiratory diseases totalled 218 cases, including instances of the common cold and upper respiratory inflammation

5. Viruses in closed populations always require the next new

work is restricted.

Figure 8.

110

Figure 7.

and there is a gradual decreasing trend thereafter.

Antarctica - A Key to Global Change

and preventive measures.

population to survive

A cold outbreak on the Icebreaker ship and at Syowa Station after the ship's arrival. The number of newly coldaffected people is shown by period: early (e-), middle (m-), and late (l-) in each month. Groups include "ship crews" and "JARE 40", who were new expedition members arriving from Japan on the ship as part of the 40th expedition. Members of the JARE 39th expedition were divided into three groups when the ship arrived at the station: 25 members were at the station; 6 members were at Dome Fuji base, returning to the station back in January; and 8 members were absent on meteorite survey inland and came back in February.

infected have acquired immunity. Looking at the disease occurrences by month, it is shown that respiratory ailments are frequent at the beginning of overwintering and then decrease gradually until soaring in prevalence in December. It is commonly known among Antarctic excursion members that a cold outbreak will present as soon as a ship has come for the first time in a year.

In one example, when the ship arrived at the station where the participants of the 39th season were finishing their 1-year term, 25 members stayed on at Syowa Station. Six members of Dome F corps and eight members of the meteorite corps were absent when the ship arrived.

A cold epidemic occurred among the outbound ship crews and new expeditioners on the ship (Figure 10). The outbreak was dying down when the ship arrived at Syowa Station. Immediately after the ship's arrival, an outbreak of colds occurred among the station members. When the Dome F team came back to the station, the outbreak had almost faded but two of six members caught a cold. Eight members of the meteorite corps came back to the station, 1 month after the arrival of the ship, and no cold case was recorded. This is an extremely interesting demonstration of virus behaviour in a closed group.

#### 6. Diseases and daily living factors

There were 199 documented injuries and diseases in 1 year among the 39th team, which had 39 participants. The causes of all cases were investigated.

occurrence of injuries and diseases in addition to pointing out the relevance of

The number of medical cases per capita on the 39th wintering-over team. The wintering team of JARE 39th was composed of 39 participants and had 199 medical consultations. Frequency of injury and disease was compared between research and logistical members, between generations. (Quoted from reference [7] and partially

sports, movies, drinking, and more. Members are responsible for several tasks beyond their official work. These activities are thought to create an atmosphere promoting strong and smooth relationships at the station to prevent loneliness. The sports team organises monthly events such as baseball, golf, and dodge-ball matches. Golfing in the snow has resulted in many lost balls. A beautiful game of football was once played on sea ice with diamond dust sparkling in the sky. However, few members are familiar with playing sports on the snow and ice; as a result, sports activities cause 10% of medical consultations during overwintering. Despite the potential for injuries, sports are believed to contribute to the prevention of severe medical cases by allowing members to experience and enjoy the Antarctic environment.

At Syowa Station, there are up to 10 activity teams for entertainment, farming,

The entertainment team plans season-based events in monotonous Antarctica. For instance, in July,Tanabata, a Japanese traditional star festival, is celebrated. Everyone hangs two wish cards on a bamboo-like branch. Wishes recorded on the cards were as follows: 29% of participants wished for "Safety & Health", 26% for "Something not in Antarctica", 21% for "Family", 16% each for "Work", "Lover", and "Weight loss". The wishes are considered to be different expressions of experienced stressors. This result is similar to finding from a study on single Japanese individuals living overseas.

Entering the overwintering period, the day, ever shortening, finally disappears. Losing sunshine for a complete day is characterised by the experience of darkness, coldness, and a sense of the solar loss. People feel sleepy at noon and have difficulty sleeping at night. Confusion abounds; when a person wakes up and sees the clock showing 1 o'clock in the dark, he or she cannot judge quickly whether it is daytime

physical age in extreme environments.

Figure 12.

Human Beings in Antarctica

DOI: http://dx.doi.org/10.5772/intechopen.81974

modified.)

8. Losing the sun

or the middle of the night.

113

7. Bond strengthening at Antarctic stations

Diseases and injuries that occurred during overwintering are classified into three categories: health problems attributable to the natural environment (63 cases), cases related to indoor and outdoor work (55 cases), and cases related to daily life other than tasks (34 cases). The monthly number of these three categories is shown in Figure 11.

Natural environment-related diseases are frequent in the coldest season. Workrelated diseases are high at the beginning of overwintering and from spring to summer, when outdoor activities are resumed. Lifestyle-related issues occurred throughout the year, with a tendency to increase at the beginning and end of overwintering.

Human factors may also be at play. Looking at the number of medical cases per capita among the team, there was no difference between researchers and logistical members. However, a clear difference was shown among generations; the morbidity rate is lowest in the 40s and higher among members in their 20s and 50s (Figure 12) [7]. This suggests that life experience might be involved in the

#### Figure 11.

Monthly change in number of diseases attributed to natural environment, work and ordinary life. Among 199 cases that occurred during one year at Syowa Station from February 1998 to January 1999, 63 cases were due to natural environment, 55 cases to work, and 34 cases to daily life. There was a seasonal change in occurrence in each disease category.

#### Figure 12.

infected have acquired immunity. Looking at the disease occurrences by month, it is shown that respiratory ailments are frequent at the beginning of overwintering and then decrease gradually until soaring in prevalence in December. It is commonly known among Antarctic excursion members that a cold outbreak will present as

In one example, when the ship arrived at the station where the participants of the 39th season were finishing their 1-year term, 25 members stayed on at Syowa Station. Six members of Dome F corps and eight members of the meteorite corps

expeditioners on the ship (Figure 10). The outbreak was dying down when the ship arrived at Syowa Station. Immediately after the ship's arrival, an outbreak of colds occurred among the station members. When the Dome F team came back to the station, the outbreak had almost faded but two of six members caught a cold. Eight members of the meteorite corps came back to the station, 1 month after the arrival of the ship, and no cold case was recorded. This is an extremely interesting demon-

There were 199 documented injuries and diseases in 1 year among the 39th team,

Diseases and injuries that occurred during overwintering are classified into three categories: health problems attributable to the natural environment (63 cases), cases related to indoor and outdoor work (55 cases), and cases related to daily life other than tasks (34 cases). The monthly number of these three categories is shown in Figure 11. Natural environment-related diseases are frequent in the coldest season. Workrelated diseases are high at the beginning of overwintering and from spring to summer, when outdoor activities are resumed. Lifestyle-related issues occurred throughout the year, with a tendency to increase at the beginning and end of overwintering. Human factors may also be at play. Looking at the number of medical cases per capita among the team, there was no difference between researchers and logistical members. However, a clear difference was shown among generations; the morbidity rate is lowest in the 40s and higher among members in their 20s and 50s (Figure 12) [7]. This suggests that life experience might be involved in the

Monthly change in number of diseases attributed to natural environment, work and ordinary life. Among 199 cases that occurred during one year at Syowa Station from February 1998 to January 1999, 63 cases were due to natural environment, 55 cases to work, and 34 cases to daily life. There was a seasonal change in occurrence in

which had 39 participants. The causes of all cases were investigated.

A cold epidemic occurred among the outbound ship crews and new

soon as a ship has come for the first time in a year.

were absent when the ship arrived.

Antarctica - A Key to Global Change

stration of virus behaviour in a closed group.

6. Diseases and daily living factors

Figure 11.

112

each disease category.

The number of medical cases per capita on the 39th wintering-over team. The wintering team of JARE 39th was composed of 39 participants and had 199 medical consultations. Frequency of injury and disease was compared between research and logistical members, between generations. (Quoted from reference [7] and partially modified.)

occurrence of injuries and diseases in addition to pointing out the relevance of physical age in extreme environments.

## 7. Bond strengthening at Antarctic stations

At Syowa Station, there are up to 10 activity teams for entertainment, farming, sports, movies, drinking, and more. Members are responsible for several tasks beyond their official work. These activities are thought to create an atmosphere promoting strong and smooth relationships at the station to prevent loneliness.

The sports team organises monthly events such as baseball, golf, and dodge-ball matches. Golfing in the snow has resulted in many lost balls. A beautiful game of football was once played on sea ice with diamond dust sparkling in the sky. However, few members are familiar with playing sports on the snow and ice; as a result, sports activities cause 10% of medical consultations during overwintering. Despite the potential for injuries, sports are believed to contribute to the prevention of severe medical cases by allowing members to experience and enjoy the Antarctic environment.

The entertainment team plans season-based events in monotonous Antarctica. For instance, in July,Tanabata, a Japanese traditional star festival, is celebrated. Everyone hangs two wish cards on a bamboo-like branch. Wishes recorded on the cards were as follows: 29% of participants wished for "Safety & Health", 26% for "Something not in Antarctica", 21% for "Family", 16% each for "Work", "Lover", and "Weight loss". The wishes are considered to be different expressions of experienced stressors. This result is similar to finding from a study on single Japanese individuals living overseas.

#### 8. Losing the sun

Entering the overwintering period, the day, ever shortening, finally disappears. Losing sunshine for a complete day is characterised by the experience of darkness, coldness, and a sense of the solar loss. People feel sleepy at noon and have difficulty sleeping at night. Confusion abounds; when a person wakes up and sees the clock showing 1 o'clock in the dark, he or she cannot judge quickly whether it is daytime or the middle of the night.

The festival consists of certain special events and a grand dinner. Anticipation of this celebration, and preparation for the events and dinner, gives the station a bright

This festival has been held since the time of Amundsen and Scott, competitive pioneers who each sought to be the first to reach the South Pole. Even now, the midwinter festival is held at most Antarctic stations, which send congratulatory

After the festival, the participants plod through the other half of the polar night

In mid-July, people gather at a small hill behind the station. At noon, the sun shines over the side of an iceberg for a moment before sinking behind another one.

moment, when the sun peeks all too briefly out to turn the blue world to an orange shine, each member of the crew witnesses the scene and feels the moment intensely. Despite the sun's gradual return, the cold becomes increasingly severe, yet outdoor operations increase with the daylight. Each person has clear tasks. During

Antarctica is covered by ice that averages 2000 m in thickness. Therefore, the Antarctic inland is an extremely cold place, and the air is rarefied. Dome Fuji Base (Dome F), an inland Antarctic research base operated by Japan, is located at S77°19<sup>0</sup>

. It is 3810 m above sea level and separated from Syowa Station by about

In general, an inland JARE party typically comprising around 10 members leaves

1000 km (Figure 14). The annual mean temperature at Dome F is �54.3°C; the

Syowa Station with several large snow vehicles on a 4-week drives to Dome F. Extreme environmental conditions in the Antarctic inland may cause hypoxia, mountain sickness, frostbite, depression, and so on. To better protect the safety of excursion members during Antarctic inland expeditions, we are collecting physio-

Dome Fuji Base. It is located at S 77°, E 39°, 3810 m above sea level and separated from Syowa Station by about 1000 km, where the snow field extends as far as the eye can see. Most of the base facilities are under the

,

season, and the blurred line between reality and dreams stretches on.

this period, sleep quality and rhythm improve.

10. Physiological changes in the Antarctic inland

lowest temperature (�79.7°C) was recorded in 1996.

logical data from members of inland parties.

The polar night season is over. Although the end of darkness is only a short

atmosphere for several days.

DOI: http://dx.doi.org/10.5772/intechopen.81974

Human Beings in Antarctica

messages to one another.

E39°42<sup>0</sup>

Figure 14.

snow.

115

#### Figure 13.

Trend of sleeping hours of one crew member. The vertical axis shows the period from May to July, while the horizontal axis depicts the time of day; the green belt is the sleeping time. The person is a male mechanical member in his twenties. He originally had a habit of staying up late. Regularity of sleeping hours disappears during the polar night period. After the polar night is over, his work-load increases, which improves sleeping patterns.

The human biorhythm is said to consist of a 25-hour cycle, which is 1 hour longer than a normal day. This cycle is reset by the brightness of morning sunshine.

During polar nights, the sun never appears during the day. The human biorhythm will not be reset and will fall into its 25-hour cycle. As social life is another trigger to reset this rhythm apart from light, the regimented timetable of station life ensures that the rhythm sustains the typical 24-hour cycle.

However, during this period, outdoor activities cannot be carried out because of the darkness, a measure to prevent accidents. Monotonous days become the norm and are less effective in resetting the circadian rhythm (Figure 13).

In addition to sleep disturbances, the darkness, cold, and confined nature of station life also make people feel depressed or uneasy.

#### 9. Midwinter

Surviving this dark period safely is one of the biggest goals of station management. Various innovative activities have been initiated to address the issue. One of them is the midwinter festival.

The summer solstice of the northern hemisphere in late June coincides with the midwinter day, which is celebrated grandly in Antarctica.

#### Human Beings in Antarctica DOI: http://dx.doi.org/10.5772/intechopen.81974

The festival consists of certain special events and a grand dinner. Anticipation of this celebration, and preparation for the events and dinner, gives the station a bright atmosphere for several days.

This festival has been held since the time of Amundsen and Scott, competitive pioneers who each sought to be the first to reach the South Pole. Even now, the midwinter festival is held at most Antarctic stations, which send congratulatory messages to one another.

After the festival, the participants plod through the other half of the polar night season, and the blurred line between reality and dreams stretches on.

In mid-July, people gather at a small hill behind the station. At noon, the sun shines over the side of an iceberg for a moment before sinking behind another one. The polar night season is over. Although the end of darkness is only a short moment, when the sun peeks all too briefly out to turn the blue world to an orange shine, each member of the crew witnesses the scene and feels the moment intensely.

Despite the sun's gradual return, the cold becomes increasingly severe, yet outdoor operations increase with the daylight. Each person has clear tasks. During this period, sleep quality and rhythm improve.

## 10. Physiological changes in the Antarctic inland

Antarctica is covered by ice that averages 2000 m in thickness. Therefore, the Antarctic inland is an extremely cold place, and the air is rarefied. Dome Fuji Base (Dome F), an inland Antarctic research base operated by Japan, is located at S77°19<sup>0</sup> , E39°42<sup>0</sup> . It is 3810 m above sea level and separated from Syowa Station by about 1000 km (Figure 14). The annual mean temperature at Dome F is �54.3°C; the lowest temperature (�79.7°C) was recorded in 1996.

In general, an inland JARE party typically comprising around 10 members leaves Syowa Station with several large snow vehicles on a 4-week drives to Dome F. Extreme environmental conditions in the Antarctic inland may cause hypoxia, mountain sickness, frostbite, depression, and so on. To better protect the safety of excursion members during Antarctic inland expeditions, we are collecting physiological data from members of inland parties.

#### Figure 14.

Dome Fuji Base. It is located at S 77°, E 39°, 3810 m above sea level and separated from Syowa Station by about 1000 km, where the snow field extends as far as the eye can see. Most of the base facilities are under the snow.

The human biorhythm is said to consist of a 25-hour cycle, which is 1 hour longer than a normal day. This cycle is reset by the brightness of morning sunshine. During polar nights, the sun never appears during the day. The human biorhythm will not be reset and will fall into its 25-hour cycle. As social life is another trigger to reset this rhythm apart from light, the regimented timetable of station life

Trend of sleeping hours of one crew member. The vertical axis shows the period from May to July, while the horizontal axis depicts the time of day; the green belt is the sleeping time. The person is a male mechanical member in his twenties. He originally had a habit of staying up late. Regularity of sleeping hours disappears during the polar night period. After the polar night is over, his work-load increases, which improves sleeping patterns.

However, during this period, outdoor activities cannot be carried out because of the darkness, a measure to prevent accidents. Monotonous days become the norm

In addition to sleep disturbances, the darkness, cold, and confined nature of

Surviving this dark period safely is one of the biggest goals of station management. Various innovative activities have been initiated to address the issue. One of

The summer solstice of the northern hemisphere in late June coincides with the

ensures that the rhythm sustains the typical 24-hour cycle.

station life also make people feel depressed or uneasy.

midwinter day, which is celebrated grandly in Antarctica.

9. Midwinter

114

Figure 13.

Antarctica - A Key to Global Change

them is the midwinter festival.

and are less effective in resetting the circadian rhythm (Figure 13).

None of the participants suffered from severe mountain sicknesses like pulmonary or brain oedema, although some experienced headache, fatigue, sleep disturbance, or elevated blood pressure because of the slow increase in altitude. Most of party members remained in relatively good health during their Dome F stay. This demonstrates that humans can successfully survive in and acclimate to the extreme

After the polar night, daytime becomes longer by 5 hours a month, leading into the white night season. There are four clear seasons with noticeable light changes in

In October, the sun reflects on brand-new, pure white snow and ice, creating a

We have compared the ultraviolet rays in Antarctica in October with those at the

The results show that ultraviolet rays emanating from the sun's precise direction

Diseases caused by ultraviolet rays include dermatitis, conjunctivitis, and facial dermatitis. The incidence of these issues is low in winter and tends to increase in summer, which shows a correlation with the quantity of ultraviolet rays encountered. The highest incidence spans from October to December. Looking at the number of occurrences at this time in terms of annual change, a trend of gradual

Change in UVB radiation dose by latitude, season, direction, and time of day. Measurement of the ultraviolet ray radiation doses was conducted at S 18°on November 25, when the sun is directly overhead, and at Syowa Station in December (during the white nights), March, April, and November (under the ozone hole). The measurement was made every hour from 7:00 to 19:00 in four directions (zenith, direct sunlight direction, horizontal direction of the sun's direction, and horizontal direction opposite to the sun). Ultraviolet rays in Antarctica in November were as strong as those at the equator. Ultraviolet rays irradiating the face of a person were stronger in Antarctica because of the low sun and the reflection by the snow and ice. (Quoted from

The ozone hole was first observed in 1980, and it continues to expand. Ultraviolet rays from space are pouring through the hole in the ozone layer,

are as strong as those at the equator, and that the ultraviolet rays irradiating a person's face are stronger in Antarctica because of the low sun and reflection by the

environmental conditions in the Antarctic inland.

Antarctica.

Figure 17.

117

reference [9] and partially modified.)

which normally blocks them.

equator (Figure 17) [10].

Human Beings in Antarctica

DOI: http://dx.doi.org/10.5772/intechopen.81974

snow and ice (Figure 18).

11. Human being as an indicator of Ozone hole

world of light. During this time, the ozone hole is emphasised.

#### Figure 15.

Trends in the serum concentration of erythropoietin and red blood cell count. Sampling point: A, Syowa Station (29 m); B, 3032 m; C, Dome F; D, 2960 m; E 2077 m; F, Syowa Station.

Among party members, the serum concentration of erythropoietin quickly increased, subsequently leading to increased red blood cell count in a sevenmember party which sets out during the austral summer of 1999–2000 (Figure 15). Haematological adaptation to a high altitude was completed in several weeks [8]. Percutaneous arterial blood oxygen saturation (SpO2) levels from four parties (totalling 33 members) had a significant negative correlation with higher elevation above sea levels. However, after arriving at Dome F, party members` SpO2 levels showed a positive correlation in the duration of their stay. This may be explained by effective high-altitude adaptation [9] (Figure 16).

#### Figure 16.

Correlation between percutaneous arterial blood oxygen saturation (SpO2) levels and altitude above sea level (left), and duration of stay (days) at Dome F (right).

None of the participants suffered from severe mountain sicknesses like pulmonary or brain oedema, although some experienced headache, fatigue, sleep disturbance, or elevated blood pressure because of the slow increase in altitude. Most of party members remained in relatively good health during their Dome F stay. This demonstrates that humans can successfully survive in and acclimate to the extreme environmental conditions in the Antarctic inland.
