Medical geology is an emerging interdisciplinary scientific field studying the relationship between natural

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

factors and their effects on

human Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, cultu ...

and

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

health Health, according to the World Health Organization, is "a state of complete physical, mental and social well-being and not merely the absence of disease and infirmity".World Health Organization. (2006)''Constitution of the World Health Organiza ...

. 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.''Finkelman, R.B., Skinner, H. C. W., Plumlee G. S. & Bunnell, J. E. 2001. Medical Geology. Geotimes. http://www.agiweb.org/geotimes/nov01/feature_medgeo.html

History

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

Hippocrates Hippocrates of Kos (; grc-gre, Ἱπποκράτης ὁ Κῷος, Hippokrátēs ho Kôios; ), also known as Hippocrates II, was a Greek physician of the classical period who is considered one of the most outstanding figures in the history o ...

and

Aristotle Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of ph ...

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, the father of pharmacology (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 or extreme climate events includes unexpected, unusual, severe, or unseasonal weather; weather at the extremes of the historical distribution—the range that has been seen in the past. Often, extreme events are based on a loca ...

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 an area of study of the discipline hydrolog ...

. *

Lead Lead is a chemical element with the symbol Pb (from the Latin ) and atomic number 82. It is a heavy metal that is denser than most common materials. Lead is soft and malleable, and also has a relatively low melting point. When freshly cu ...

and other heavy metal exposure resulting from

dust Dust is made of 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 process), volcanic eruptions, and pollution. Dust in ho ...

and other

particulates Particulates – also known as atmospheric aerosol particles, atmospheric particulate matter, particulate matter (PM) or suspended particulate matter (SPM) – are microscopic particles of solid or liquid matter suspended in the air. The t ...

* Asbestos exposure such as amphibole asbestos dusts in Libby, Montana *

Fungal A fungus ( : fungi 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 a kingdom, separately from th ...

infection An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable dis ...

resulting from airborne dust, such as

Valley Fever A valley is an elongated low area often running between hills or mountains, which will typically contain a river or stream running from one end to the other. Most valleys are formed by erosion of the land surface by rivers or streams ove ...

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

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 chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed ...

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 Wales ...

s have an impact on

and

populations because that is what the

earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ...

is composed of. Medical geology brings professionals from both the

medicine Medicine is the science and practice of caring for a patient, managing the diagnosis, prognosis, prevention, treatment, palliation of their injury or disease, and promoting their health. Medicine encompasses a variety of health care pr ...

field and the

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

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, also called minor element, is a chemical element whose concentration (or other measure of amount) is very low (a "trace amount"). They are classified into two groups: essential and non-essential. Essential trace elements ...

, 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%. Ho ...

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 spoils, corrupts, infects, makes unfit, or makes inferior a material, physical body, natural environment, workplace, etc. Types of contamination ...

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 (chemical formula ) is an Inorganic compound, inorganic, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living ...

soil Soil, also commonly referred to as earth or dirt Dirt is an unclean matter, especially when in contact with a person's clothes, skin, or possessions. In such cases, they are said to become dirty. Common types of dirt include: * Debri ...

air The atmosphere of Earth is the layer of gases, known collectively as air, retained by Earth's gravity that surrounds the planet and forms its planetary atmosphere. The atmosphere of Earth protects life on Earth by creating pressure allowing f ...

, food, 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 Maputaland is a natural region of Southern Africa. It is located in the northern part of the province of KwaZulu-Natal, South Africa between Eswatini and the coast. In a wider sense it may also include the southernmost region of Mozambique. The bi ...

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. It is bounded to the south by of coastline that stretch along the Atlantic Ocean, South Atlantic and Indian Oceans; to the ...

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 chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2 ...

imbalances. Secondly, those in areas such as

India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...

and

Bangladesh Bangladesh (}, ), officially the People's Republic of Bangladesh, is a country in South Asia. It is the eighth-most populous country in the world, with a population exceeding 165 million people in an area of . Bangladesh is among the mos ...

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, bacterium, or plant, as well as the effect on a subs ...

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

. 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'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture, ...

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 a rupture 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 found where tectonic plates a ...

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 form of matter having constant chemical composition and characteristic properties. Some references add that chemical substance cannot be separated into its constituent elements by physical separation methods, i.e., wit ...

such as;

arsenic Arsenic is a chemical element with the symbol As and atomic number 33. Arsenic occurs in many minerals, usually in combination with sulfur and metals, but also as a pure elemental crystal. Arsenic is a metalloid. It has various allotropes, ...

beryllium Beryllium is a chemical element with the symbol Be and atomic number 4. It is a steel-gray, strong, lightweight and brittle alkaline earth metal. It is a divalent element that occurs naturally only in combination with other elements to form m ...

cadmium Cadmium is a chemical element with the symbol Cd and atomic number 48. This soft, silvery-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Like zinc, it demonstrates oxidation state +2 in most of ...

, mercury,

lead Lead is a chemical element with the symbol Pb (from the Latin ) and atomic number 82. It is a heavy metal that is denser than most common materials. Lead is soft and malleable, and also has a relatively low melting point. When freshly cu ...

radon Radon is a chemical element with the symbol Rn and atomic number 86. It is a radioactive, colourless, odourless, tasteless noble gas. It occurs naturally in minute quantities as an intermediate step in the normal radioactive decay chains through ...

, and

uranium Uranium is a chemical element with the 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. Uranium is weak ...

. *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 diseases is

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 cong ...

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

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

and brain damage. The

sea The sea, connected as the world ocean or simply the ocean, is the body of salty water that covers approximately 71% of the Earth's surface. The word sea is also used to denote second-order sections of the sea, such as the Mediterranean Sea, ...

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

; however, goitrogens such as humus and

clay Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4). Clays develop plasticity when wet, due to a molecular film of water surrounding the clay par ...

trap the iodine, making it hard for people to access it. Some

cultures Culture () is an umbrella term which encompasses the social behavior, institutions, and norms found in human societies, as well as the knowledge, beliefs, arts, laws, customs, capabilities, and habits of the individuals in these groups.Tylo ...

actually consume the earth's

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

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 relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the sout ...

engage in this practice and none have suffered from any

problems related with mineral/ Iodine deficiency.

Cardiovascular disease

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

magnesium Magnesium is a chemical element with the 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 of the periodic ta ...

in the water with

calcium Calcium is a chemical element with the 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 t ...

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 is found everywhere; it is in the

, rocks,

and food. The largest amount of radiation comes from

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

Guarapari Guarapari is a coastal town of Espírito Santo, Brazil, a popular tourist destination. Its beach is famous for the high natural radioactivity level of its sand. Location Guarapari is a part of Greater Vitoria, 47 km south of the state capital ...

, Southwest of

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan area ...

Ramsar Ramsar may refer to: * Places so named: ** Ramsar, Mazandaran, city in Iran ** Ramsar, Rajasthan, village in India * Eponyms of the Iranian city: ** Ramsar Convention concerning wetlands, signed in Ramsar, Iran ** Ramsar site, wetland listed in ...

, parts of China, 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 in

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

and

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...

Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the east a ...

, and

Taiwan Taiwan, officially the Republic of China (ROC), is a country in East Asia, at the junction of the East and South China Seas in the northwestern Pacific Ocean, with the People's Republic of China (PRC) to the northwest, Japan to the nort ...

selenium Selenium is a chemical element with the symbol Se and atomic number 34. It is a nonmetal (more rarely considered a metalloid) with properties that are intermediate between the elements above and below in the periodic table, sulfur and tellurium, ...

in areas of the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

Venezuela Venezuela (; ), officially the Bolivarian Republic of Venezuela ( es, link=no, República Bolivariana de Venezuela), is a country on the northern coast of South America, consisting of a continental landmass and many islands and islets in th ...

, China and nitrate in agricultural areas. As medical geology grows it may become more important to the

medical Medicine is the science and practice of caring for a patient, managing the diagnosis, prognosis, prevention, treatment, palliation of their injury or disease, and promoting their health. Medicine encompasses a variety of health care practic ...

field in relation to the issue of diseases. 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 solid, liquid, and gaseous matter that constitutes Earth and other terrestrial planets, as well as the processes that shape them. Geologists usually study geology, earth science, or geophysics, althou ...

and earth scientists, environmental scientists,

toxicologists Toxicology is a scientific discipline, overlapping with biology, chemistry, pharmacology, and medicine, that involves the study of the adverse effects of chemical substances on living organisms and the practice of diagnosing and treating ex ...

epidemiologists Epidemiology is the study and analysis of the distribution (who, when, and where), patterns and determinants of health and disease conditions in a defined population. It is a cornerstone of public health, and shapes policy decisions and eviden ...

, 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 (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