Environmental Hazards, Hot, Cold, Altitude, and Sun
Section snippets
Extreme environments
Humans have colonized most areas of the planet, including areas where the environmental conditions are extremely harsh. Native populations to these areas have developed strategies that include clothing, shelter, technology, and behavior, as well as physiologic adaptation, over generations. Short-term visitors can adjust to these austere environments provided they have the knowledge and time to acclimatize sufficiently. There has been an increase in both recreational and adventure travel to
Heat-related disorders
Humans are well adapted to hot climates but require a period of acclimatization from cold/temperate climates, especially in humid conditions. There is considerable variability of thermal tolerance between individuals, but ultimately everyone will succumb if the duration and intensity of exposure are sufficiently challenging.
Accidental Hypothermia
Hypothermia occurs when the core temperature decreases to less than 35°C and can be classified as mild (35°–32°C), moderate (32°–28°C), or severe (<28°C).15, 16 The Swiss classification should be used in the field by rescuers.17 Risk factors for hypothermia include extremes of age, homelessness, trauma, poor nutrition, exhaustion, mental illness, and alcohol and drug abuse.
Hypothermia affects almost every organ system. Cerebral metabolism increases initially but then declines by 6% for each 1°C
Summary
Humans can successfully acclimatize to and perform reasonably well in extreme environments, provided that sufficient time is given for acclimatization (where possible) and if they use appropriate behavior. This is aided by a knowledge of the problems likely to be encountered and their prevention, recognition, and treatment.
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Cited by (9)
Effects of long-term average temperature on cardiovascular disease hospitalizations in an American elderly population
2023, Environmental ResearchCitation Excerpt :Our study could not disentangle if associations of seasonal temperature exposures with CVD hospitalization are due to cumulative effects of short-term exposures or physiological responses of long-term exposures. Exposure to high temperatures can result in a lowered metabolic rate, increased blood volume and increased sweat production (Dhillon, 2012; Périard et al., 2016). Exposure to low temperatures on the other hand can lead to vasoconstriction, inflammatory responses and elevated resting metabolism and blood viscosity (Tansey and Johnson, 2015; Castellani and Young, 2016; Woodhouse et al., 1993, 1994; Keatinge et al., 1984).
Health issues of travelers
2019, Encyclopedia of Environmental HealthHigh temperatures and nephrology: The climate change problem
2017, NefrologiaCitation Excerpt :In heat exhaustion, core body temperature never rises above 40 °C and one's mental status remains unchanged. The clinical symptoms vary: tachypnoea, tachycardia, nausea, vomiting, sweating, myalgia, skin redness, headache, etc.29,30 In heat stroke, core body temperature rises to 41.5–42 °C and causes cell damage, a clinical condition that is due to the systemic inflammatory response syndrome that is triggered and the disseminated intravascular coagulation caused by the activation of a coagulation cascade. The liver and the central nervous system are primarily affected and, vertigo, confusion, ataxia and coma may occur.
Abnormalities of Thermal Regulation and the Nervous System
2014, Aminoff's Neurology and General Medicine: Fifth EditionIs altitude a determinant of the health benefits of nature exposure? A systematic review and meta-analysis
2022, Frontiers in Public HealthAdventurous tourism: acclimatization problems and decisions in trans-boundary travels
2021, International Journal of Biometeorology
The author has nothing to disclose.