Medical geology is an

interdisciplinary Interdisciplinarity or interdisciplinary studies involves the combination of multiple academic disciplines into one activity (e.g., a research project). It draws knowledge from several fields such as sociology, anthropology, psychology, economi ...

scientific field studying the relationship between natural

geological Geology (). is a branch of natural science concerned with the Earth and other astronomical objects, the rocks of which they are composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth s ...

factors and their effects on

human Humans (''Homo sapiens'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are Hominidae, great apes characterized by their Prehistory of nakedness and clothing ...

and

animal health Animal Health was a UK government executive agency primarily responsible for ensuring that farmed animals in Great Britain were healthy, disease-free and well looked after. One of its key roles was to implement government policies aimed at preve ...

. The Commission on Geological Sciences for Environmental Planning defines medical geology as "the science dealing with the influence of ordinary environmental factors on the geographical distribution of health problems in man and animals." :''In its broadest sense, medical geology studies exposure to or deficiency of trace elements and minerals; inhalation of ambient and anthropogenic mineral dusts and volcanic emissions; transportation, modification and concentration of organic compounds; and exposure to radionuclides, microbes and pathogens.''

History

Many have deemed medical geology as a new field, when in actuality it is re-emerging.

Hippocrates Hippocrates of Kos (; ; ), also known as Hippocrates II, was a Greek physician and philosopher of the Classical Greece, classical period who is considered one of the most outstanding figures in the history of medicine. He is traditionally referr ...

and

Aristotle Aristotle (; 384–322 BC) was an Ancient Greek philosophy, Ancient Greek philosopher and polymath. His writings cover a broad range of subjects spanning the natural sciences, philosophy, linguistics, economics, politics, psychology, a ...

first recognized the relationship between human diseases and the earth's elements. This field ultimately depends on a number of different fields coming and working together to solve some of the earth's mysteries. The scientific term for this field is ''hydrobiogeochemoepidemiopathoecology''; however, it is more commonly known as medical geology. It was established in 1990 by the International Union of Geological Sciences.

Paracelsus Paracelsus (; ; 1493 – 24 September 1541), born Theophrastus von Hohenheim (full name Philippus Aureolus Theophrastus Bombastus von Hohenheim), was a Swiss physician, alchemist, lay theologian, and philosopher of the German Renaissance. H ...

, the "father of

pharmacology Pharmacology is the science of drugs and medications, including a substance's origin, composition, pharmacokinetics, pharmacodynamics, therapeutic use, and toxicology. More specifically, it is the study of the interactions that occur betwee ...

" (1493–1541), stated that "all substances are poisons, there is none which is not a poison. The right dosage differentiates a poison and a remedy." This passage sums up the idea of medical geology. The goal of this field is to find the right balance and intake of elements/minerals in order to improve and maintain health. Examples of research in medical geology include: * Studies on the impact of contaminant mobility as a result of

extreme weather Extreme weather includes unexpected, unusual, severe weather, severe, or unseasonal weather; weather at the extremes of the historical distribution—the range that has been seen in the past. Extreme events are based on a location's recorded weat ...

events such as

flooding A flood is an overflow of water ( or rarely other fluids) that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are of significant concern in agriculture, civi ...

. *

Lead Lead () is a chemical element; it has Chemical symbol, symbol Pb (from Latin ) and atomic number 82. It is a Heavy metal (elements), heavy metal that is density, denser than most common materials. Lead is Mohs scale, soft and Ductility, malleabl ...

and other heavy metal exposure resulting from

dust Dust is made of particle size, fine particles of solid matter. On Earth, it generally consists of particles in the atmosphere that come from various sources such as soil lifted by wind (an aeolian processes, aeolian process), Types of volcan ...

and other

particulates Particulate matter (PM) or particulates are microscopic particles of solid or liquid matter suspension (chemistry), suspended in the atmosphere of Earth, air. An ''aerosol'' is a mixture of particulates and air, as opposed to the particulate ...

Asbestos Asbestos ( ) is a group of naturally occurring, Toxicity, toxic, carcinogenic and fibrous silicate minerals. There are six types, all of which are composed of long and thin fibrous Crystal habit, crystals, each fibre (particulate with length su ...

exposure such as

amphibole Amphibole ( ) is a group of inosilicate minerals, forming prism or needlelike crystals, composed of double chain tetrahedra, linked at the vertices and generally containing ions of iron and/or magnesium in their structures. Its IMA symbol is ...

asbestos dusts in

Libby, Montana Libby is a city in northwestern Montana, United States and the county seat of Lincoln County, Montana, Lincoln County. The population was 2,775 at the 2020 United States census, 2020 census. Libby suffered from the area's contamination from nea ...

Fungal A fungus (: fungi , , , or ; or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as one of the tradit ...

infection An infection is the invasion of tissue (biology), tissues by pathogens, their multiplication, and the reaction of host (biology), host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmis ...

resulting from airborne dust, such as Valley Fever or

coccidioidomycosis Coccidioidomycosis (, ) is a mammalian mycosis, fungal disease caused by ''Coccidioides immitis'' or ''Coccidioides posadasii''. It is commonly known as cocci, Valley fever, California fever, desert rheumatism, or San Joaquin Valley fever. Cocci ...

Recently, a new concept of "geomedical engineering" has been introduced in medical geology through a paper titled "Geomedical Engineering: A new and captivating prospect". It provides the fundamentals of engineering applications to the medical geology issues.

Environment and human health

It is widely known that the state of our environment affects us in many ways.

Minerals In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid substance with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2011): M ...

and

rock Rock most often refers to: * Rock (geology), a naturally occurring solid aggregate of minerals or mineraloids * Rock music, a genre of popular music Rock or Rocks may also refer to: Places United Kingdom * Rock, Caerphilly, a location in Wale ...

s have an impact on

and

animal Animals are multicellular, eukaryotic organisms in the Biology, biological Kingdom (biology), kingdom Animalia (). With few exceptions, animals heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, ...

populations because that is what the

earth Earth is the third planet from the Sun and the only astronomical object known to Planetary habitability, harbor life. This is enabled by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all ...

is composed of. Medical geology brings professionals from both the

medicine Medicine is the science and Praxis (process), practice of caring for patients, managing the Medical diagnosis, diagnosis, prognosis, Preventive medicine, prevention, therapy, treatment, Palliative care, palliation of their injury or disease, ...

field and the

geology Geology (). is a branch of natural science concerned with the Earth and other astronomical objects, the rocks of which they are composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth ...

field to help us understand this relationship. There are two priorities that have been established within the medical geology field, "(1) the study of

trace elements __NOTOC__ A trace element is a chemical element of a minute quantity, a trace amount, especially used in referring to a micronutrient, but is also used to refer to minor elements in the composition of a rock, or other chemical substance. In nutri ...

, especially their

bioavailability In pharmacology, bioavailability is a subcategory of absorption and is the fraction (%) of an administered drug that reaches the systemic circulation. By definition, when a medication is administered intravenously, its bioavailability is 100%. H ...

and (2) a need to establish baseline, or background levels of

contaminants Contamination is the presence of a constituent, impurity, or some other undesirable element that renders something unsuitable, unfit or harmful for the physical body, natural environment, workplace, etc. Types of contamination Within the scie ...

xenobiotics A xenobiotic is a chemical substance found within an organism that is not naturally produced or expected to be present within the organism. It can also cover substances that are present in much higher concentrations than are usual. Natural compo ...

/potentially harmful but naturally occurring materials in

water Water is an inorganic compound with the chemical formula . It is a transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance. It is the main constituent of Earth's hydrosphere and the fluids of all known liv ...

soil Soil, also commonly referred to as earth, is a mixture of organic matter, minerals, gases, water, and organisms that together support the life of plants and soil organisms. Some scientific definitions distinguish dirt from ''soil'' by re ...

air An atmosphere () is a layer of gases that envelop an astronomical object, held in place by the gravity of the object. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A stellar atmosph ...

food Food is any substance consumed by an organism for Nutrient, nutritional support. Food is usually of plant, animal, or Fungus, fungal origin and contains essential nutrients such as carbohydrates, fats, protein (nutrient), proteins, vitamins, ...

, and

tissue." The elements and minerals in the land affect people and animals immensely, especially when there is a close relationship between the two. Those who depend heavily on the land are faced with one of two problems. First, those who live in places such as Maputaland,

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...

are exposed to heavily impoverished soils which result in a number of diseases caused by

mineral In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid substance with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2011): Mi ...

imbalances. Secondly, those in areas such as

India India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...

and

Bangladesh Bangladesh, officially the People's Republic of Bangladesh, is a country in South Asia. It is the List of countries and dependencies by population, eighth-most populous country in the world and among the List of countries and dependencies by ...

are often exposed to an excess of elements in the land, resulting in

toxicity Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacteria, bacterium, or plant, as well as the effect o ...

. All living organisms need some naturally occurring elements; however, excessive amounts can be detrimental to

health Health has a variety of definitions, which have been used for different purposes over time. In general, it refers to physical and emotional well-being, especially that associated with normal functioning of the human body, absent of disease, p ...

. There is a direct link between

and the

because all humans ingest and breath in these chemicals and for the most part it is done unknowingly.

Sources of chemical exposure

There are many ways in which

humans Humans (''Homo sapiens'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are Hominidae, great apes characterized by their Prehistory of nakedness and clothing ...

come into contact with the earth's elements and below are only a few ways in which we become exposed to them. *

Volcanoes A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often fo ...

are one of the main sources that bring all the

from inside the

to the outside. They bring out

chemicals A chemical substance is a unique form of matter with constant chemical composition and characteristic properties. Chemical substances may take the form of a single element or chemical compounds. If two or more chemical substances can be combin ...

such as;

arsenic Arsenic is a chemical element; it has Symbol (chemistry), symbol As and atomic number 33. It is a metalloid and one of the pnictogens, and therefore shares many properties with its group 15 neighbors phosphorus and antimony. Arsenic is not ...

beryllium Beryllium is a chemical element; it has Symbol (chemistry), symbol Be and atomic number 4. It is a steel-gray, hard, strong, lightweight and brittle alkaline earth metal. It is a divalent element that occurs naturally only in combination with ...

cadmium Cadmium is a chemical element; it has chemical symbol, symbol Cd and atomic number 48. This soft, silvery-white metal is chemically similar to the two other stable metals in group 12 element, group 12, zinc and mercury (element), mercury. Like z ...

, mercury,

lead Lead () is a chemical element; it has Chemical symbol, symbol Pb (from Latin ) and atomic number 82. It is a Heavy metal (elements), heavy metal that is density, denser than most common materials. Lead is Mohs scale, soft and Ductility, malleabl ...

radon Radon is a chemical element; it has symbol Rn and atomic number 86. It is a radioactive noble gas and is colorless and odorless. Of the three naturally occurring radon isotopes, only Rn has a sufficiently long half-life (3.825 days) for it to b ...

, and

uranium Uranium is a chemical element; it has chemical symbol, symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Ura ...

. * Rocks are also one of the leading sources in exposure to these elements. "They are essentially the source of all the naturally occurring chemical elements found on the

Diseases

Iodine deficiency

One of the biggest

geochemical Geochemistry is the science that uses the tools and principles of chemistry to explain the mechanisms behind major geological systems such as the Earth's crust and its oceans. The realm of geochemistry extends beyond the Earth, encompassing the ...

diseases A disease is a particular abnormal condition that adversely affects the structure or function of all or part of an organism and is not immediately due to any external injury. Diseases are often known to be medical conditions that are asso ...

iodine deficiency Iodine deficiency is a lack of the trace element iodine, an essential nutrient in the diet. It may result in metabolic problems such as goiter, sometimes as an endemic goiter as well as congenital iodine deficiency syndrome due to untreated ...

. Thirty percent of the world is at risk for it and insufficient intake is the most common cause of

intellectual disability Intellectual disability (ID), also known as general learning disability (in the United Kingdom), and formerly mental retardation (in the United States), Rosa's Law, Pub. L. 111-256124 Stat. 2643(2010).Archive is a generalized neurodevelopmental ...

and

brain damage Brain injury (BI) is the destruction or degeneration of brain cells. Brain injuries occur due to a wide range of internal and external factors. In general, brain damage refers to significant, undiscriminating trauma-induced damage. A common ...

. The

sea A sea is a large body of salt water. There are particular seas and the sea. The sea commonly refers to the ocean, the interconnected body of seawaters that spans most of Earth. Particular seas are either marginal seas, second-order section ...

is a major source of

iodine Iodine is a chemical element; it has symbol I and atomic number 53. The heaviest of the stable halogens, it exists at standard conditions as a semi-lustrous, non-metallic solid that melts to form a deep violet liquid at , and boils to a vi ...

and those who are further from it are at a disadvantage. Another source of it is in

; however, goitrogens such as

humus In classical soil science, humus is the dark organic matter in soil that is formed by the decomposition of plant and animal matter. It is a kind of soil organic matter. It is rich in nutrients and retains moisture in the soil. Humus is the Lati ...

and

clay Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolinite, ). Most pure clay minerals are white or light-coloured, but natural clays show a variety of colours from impuriti ...

trap the

, making it hard for people to access it. Some

cultures Culture ( ) is a concept that encompasses the social behavior, institutions, and Social norm, norms found in human societies, as well as the knowledge, beliefs, arts, laws, Social norm, customs, capabilities, Attitude (psychology), attitudes ...

actually consume the earth's

minerals In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid substance with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2011): M ...

by eating

and

; this is known as geophagy. It is most common in the tropics, especially among pregnant women. The Ottomac people of

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

engage in this practice and none have suffered from any

problems related with mineral/ Iodine deficiency.

Cardiovascular disease

Cardiovascular disease Cardiovascular disease (CVD) is any disease involving the heart or blood vessels. CVDs constitute a class of diseases that includes: coronary artery diseases (e.g. angina, heart attack), heart failure, hypertensive heart disease, rheumati ...

has often been linked to water hardness as the main cause. Water hardness means that there is

magnesium Magnesium is a chemical element; it has Symbol (chemistry), symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 ...

in the water with

calcium Calcium is a chemical element; it has symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to it ...

playing a role. Some research has completely discredited this evidence, and has found that the more magnesium in the water the less chance of death cardiovascular disease.

Radiation

Natural

radiation In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or a material medium. This includes: * ''electromagnetic radiation'' consisting of photons, such as radio waves, microwaves, infr ...

is found everywhere; it is in the

, rocks,

and

. The largest amount of

comes from

. Certain places are called 'high background radiation areas' (HBRAs), such as Guarapari, Southwest of

France France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...

, Ramsar, parts of

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

, and Kerala Coast. People living in these areas however have not shown any

deficiencies and in some cases are even healthier and live longer than those not in HBRAs.

Other issues

Among the problems presented there are also issues with

fluoride Fluoride (). According to this source, is a possible pronunciation in British English. is an Inorganic chemistry, inorganic, Monatomic ion, monatomic Ion#Anions and cations, anion of fluorine, with the chemical formula (also written ), whose ...

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

and

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

Chile Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...

, and

Taiwan Taiwan, officially the Republic of China (ROC), is a country in East Asia. The main geography of Taiwan, island of Taiwan, also known as ''Formosa'', lies between the East China Sea, East and South China Seas in the northwestern Pacific Ocea ...

selenium Selenium is a chemical element; it has symbol (chemistry), symbol Se and atomic number 34. It has various physical appearances, including a brick-red powder, a vitreous black solid, and a grey metallic-looking form. It seldom occurs in this elem ...

in areas of the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

Venezuela Venezuela, officially the Bolivarian Republic of Venezuela, is a country on the northern coast of South America, consisting of a continental landmass and many Federal Dependencies of Venezuela, islands and islets in the Caribbean Sea. It com ...

and

nitrate Nitrate is a polyatomic ion with the chemical formula . salt (chemistry), Salts containing this ion are called nitrates. Nitrates are common components of fertilizers and explosives. Almost all inorganic nitrates are solubility, soluble in wa ...

agricultural Agriculture encompasses crop and livestock production, aquaculture, and forestry for food and non-food products. Agriculture was a key factor in the rise of sedentary human civilization, whereby farming of domesticated species created f ...

areas. As medical geology grows it may become more important to the

medical Medicine is the science and Praxis (process), practice of caring for patients, managing the Medical diagnosis, diagnosis, prognosis, Preventive medicine, prevention, therapy, treatment, Palliative care, palliation of their injury or disease, ...

field in relation to the issue of

. In addition to deficiencies of particular minerals, dietary excesses of certain elements occurring in specific geographic regions can also be harmful to human health, as per the examples listed below: * Hyperkalemia: excess amount of potassium * Hypercalcemia: excess amount of calcium * Hyperphosphatemia: excess amount of phosphorus

International Medical Geology Association

"The International Medical Geology Association (IMGA) aims to provide a network and a forum to bring together the combined expertise of

geologists A geologist is a scientist who studies the structure, composition, and history of Earth. Geologists incorporate techniques from physics, chemistry, biology, mathematics, and geography to perform research in the field and the laboratory. Geolog ...

and earth scientists, environmental scientists, toxicologists, epidemiologists, and medical specialists, in order to characterize the properties of

processes and agents, the dispersal of geological material and their effects on human population." IMGA was founded in 2006 and manages affairs and funds, plans conferences, elections and publications, and they are also a way of encouraging growth and recognition in the field. Although it was founded in 2006, it was a work in progress for ten years when a working group of medical geology was established by the

International Union of Geological Sciences The International Union of Geological Sciences (IUGS) is an international non-governmental organization devoted to global cooperation in the field of geology. As of 2023, it represents more than 1 million geoscientists around the world. About Fo ...

(IUGS) in 1996. The goal of the working group was to advertise and make people aware of the harmful effects the environment has on our health.

References

USGS Medical Geology
Accessed 22 July 2006

accessed 28 January 2006
Bunnell, Joseph E. (2004) ''Medical Geology: Emerging Discipline on the Ecosystem-Human Health Interface'', Ecohealth
PDF file accessed 28 January 2007

External links

International Medical Geology Association
{{DEFAULTSORT:Medical Geology Geobiology Environmental health