Changes

[[File:UNN_Medical_Geology_Fig_2.png|thumb|400px|{{figure number|2}}Geologic cross-section of the Pikes Peak area showing the sources of fluoride in the Colorado Spring (Finkelman et al, 2010b).]]

[[File:UNN_Medical_Geology_Fig_2.png|thumb|400px|{{figure number|2}}Geologic cross-section of the Pikes Peak area showing the sources of fluoride in the Colorado Spring (Finkelman et al, 2010b).]]

Over the years, it has been observed that the environment man lives in affects his health. For instance, the people of Maputaland, South Africa, are plagued by nutrient-poor soil. Maize grown in this region has very low content of elements such as calcium, potassium and phosphorous (Selinus and Frank, 2000). This is as a result of low concentration of these elements in the rocks of that region. Countries in southern Africa also suffer from selenium deficiency in their soils. This accounts for the spread of HIV-1 virus in this zone as selenium which inhibits the replication of HIV-1 is lacking in their soil. Still in Africa, Kerala Province in Uganda is another region under the “hammer” of geology. Children in this province suffer from a ‘grave’ coronary heart condition called endomyocardial fibrosis (EMF). This epidemic is attributed to the deliberate eating of soil containing the element cerium (Davies, 2010).

Over the years, it has been observed that the environment man lives in affects his health. For instance, the people of Maputaland, South Africa, are plagued by nutrient-poor soil. Maize grown in this region has very low content of elements such as calcium, potassium and phosphorous (Selinus and Frank, 2000). This is as a result of low concentration of these elements in the rocks of that region. Countries in southern Africa also suffer from selenium deficiency in their soils. This accounts for the spread of HIV-1 virus in this zone as selenium which inhibits the replication of HIV-1 is lacking in their soil. Still in Africa, Kerala Province in Uganda is another region under the “hammer” of geology. Children in this province suffer from a ‘grave’ coronary heart condition called endomyocardial fibrosis (EMF). This epidemic is attributed to the deliberate eating of soil containing the element cerium.<ref name=Dvies>Davies, T. C., 2010. Medical Geology in Africa, ''in'' O. Selinus, R. B. Finkelman, and J. A. Centeno, eds., Medical Geology: A Regional Synthesis, 199–216.</ref>

China is not left aside in these problems. The country suffers from deficiencies and excessiveness of selenium in many parts of the country resulting in life-threatening health problems. China also suffers from the influx of arsenic into coal deposits whose domestic use has resulted to untold chronic health effects over the years (Skinner, 2007).

China is not left aside in these problems. The country suffers from deficiencies and excessiveness of selenium in many parts of the country resulting in life-threatening health problems. China also suffers from the influx of arsenic into coal deposits whose domestic use has resulted to untold chronic health effects over the years (Skinner, 2007).

Minor elements are those elements that are needed in moderate quantities; each has a concentration of 0.1% to 1.0% in the body (Selinus et al, 2013). They share in the functions of the major elements, but in smaller amounts.

Minor elements are those elements that are needed in moderate quantities; each has a concentration of 0.1% to 1.0% in the body (Selinus et al, 2013). They share in the functions of the major elements, but in smaller amounts.

Trace elements are those elements that have concentrations far below 0.1% in the body; they are needed in the body only in parts per million (ppm). They are essential to plant and animal lives only in trace amounts. Such trace elements are called essential trace elements (Christine et al, 2000). They are highly variable in their abundance in various rocks (Table 1, Khandare, 2012 ).

Trace elements are those elements that have concentrations far below 0.1% in the body; they are needed in the body only in parts per million (ppm). They are essential to plant and animal lives only in trace amounts. Such trace elements are called essential trace elements.<ref>Christine, L. E., G. Sujuan, L. Yiming, L. Chaoke, J. Rongdi, S. H. Kathleen, C. Jingxiang, M. Feng, W. Yunpeng, Y. Po, S. Shuzhuang, W. U. Frederick, W. S. Charles, and C. H. Hugh, 2000, Trace Element Levels in Drinking Water and Cognitive Function among Elderly Chinese: American Journal of Epidemiology, 151(9), 913-920.</ref> They are highly variable in their abundance in various rocks (Table 1, Khandare, 2012 ).

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====Health impacts of excessive arsenic in groundwater in Zimbabwe====

====Health impacts of excessive arsenic in groundwater in Zimbabwe====

Most parts of the African Precambrian Complex such as the Greenstone Belts have been subjected to metallic sulphide mineralization (Davies, 2010). This led to the introduction of arsenic into aquifers in many parts of Africa. Within these regions, the sulphide-loving arsenic has been introduced into the environment as a result of gold mining in Ghana and South Africa, metal sulphide mining in Zimbabwe and South Africa and coal mining in South Africa.

Most parts of the African Precambrian Complex such as the Greenstone Belts have been subjected to metallic sulphide mineralization.<ref name=Dvies /> This led to the introduction of arsenic into aquifers in many parts of Africa. Within these regions, the sulphide-loving arsenic has been introduced into the environment as a result of gold mining in Ghana and South Africa, metal sulphide mining in Zimbabwe and South Africa and coal mining in South Africa.

At Iron Duke Mine, near Mazowe, Zimbabwe, acid mine drainage (AMD) having a pH of 0.52 was encountered (Davies, 2010). This was observed during a research into the geochemistry of the mine waters of Harare, Midlands and Shamva Greenstone Belts. The mine waters from Iron Duke Mine, near Mazowe has arsenic concentration of about 72mg/l− the highest dissolved arsenic concentration on earth (Davies, 2010).

At Iron Duke Mine, near Mazowe, Zimbabwe, acid mine drainage (AMD) having a pH of 0.52 was encountered.<ref name=Dvies /> This was observed during a research into the geochemistry of the mine waters of Harare, Midlands and Shamva Greenstone Belts. The mine waters from Iron Duke Mine, near Mazowe has arsenic concentration of about 72mg/l− the highest dissolved arsenic concentration on earth.<ref name=Dvies />

====Arsenosis in China====

====Arsenosis in China====

====Water purification technologies to remove arsenic from water====

====Water purification technologies to remove arsenic from water====

Arsenic removal from water can be carried out in different ways. To do this, it is important to distinguish between different types of arsenic as different methods are applied for each of the types: organic or inorganic. Groundwater mainly contains inorganic arsenic such as the arsenides and the arsenates. Proven methods include ion exchange, membrane filtration and iron and aluminum coagulation. Buffering methods have also shown great success in removing arsenic from mine waters (Davies, 2010). In addition, sequential extraction speciation studies and geochemical modeling methods have shown great potential for removing arsenic from mine waters through the use of hydrous ferric oxides to precipitate arsenic at wide pH ranges. Arsenic removal from soils can be achieved by the use of ferns that bio-accumulate large arsenic concentrations (Davies, 2010).

Arsenic removal from water can be carried out in different ways. To do this, it is important to distinguish between different types of arsenic as different methods are applied for each of the types: organic or inorganic. Groundwater mainly contains inorganic arsenic such as the arsenides and the arsenates. Proven methods include ion exchange, membrane filtration and iron and aluminum coagulation. Buffering methods have also shown great success in removing arsenic from mine waters.<ref name=Dvies /> In addition, sequential extraction speciation studies and geochemical modeling methods have shown great potential for removing arsenic from mine waters through the use of hydrous ferric oxides to precipitate arsenic at wide pH ranges. Arsenic removal from soils can be achieved by the use of ferns that bio-accumulate large arsenic concentrations.<ref name=Dvies />

===Iodine Deficiency Disorders (IDD)===

===Iodine Deficiency Disorders (IDD)===

[[File:UNN_Medical_Geology_Fig_6.png|thumb|400px|{{figure number|6}}Man with goiter (Fuge, 2005)]]

[[File:UNN_Medical_Geology_Fig_6.png|thumb|400px|{{figure number|6}}Man with goiter (Fuge, 2005)]]

Iodine is very important for the proper functioning of the human body. In all mammals, it is needed for the efficient functioning of the adult in trace amounts in the order of 0.0004 wt% (Davies, 2010). This quantity is maintained as a result of small intake of iodine from drinking water and various forms of foodstuffs throughout the lifetime of the mammal.

Iodine is very important for the proper functioning of the human body. In all mammals, it is needed for the efficient functioning of the adult in trace amounts in the order of 0.0004 wt%.<ref name=Dvies /> This quantity is maintained as a result of small intake of iodine from drinking water and various forms of foodstuffs throughout the lifetime of the mammal.

Iodine is released into the environment through volcanic emanations. It is incorporated in sea salt and occurs in formation waters and fluid inclusions. The highest iodine concentration, however, is found in sea water; thus coastal soils are more iodine-enriched than mainland soils (Davies, 2010).

Iodine is released into the environment through volcanic emanations. It is incorporated in sea salt and occurs in formation waters and fluid inclusions. The highest iodine concentration, however, is found in sea water; thus coastal soils are more iodine-enriched than mainland soils.<ref name=Dvies />

As an evidence, traverses of the Moroccan coast show that the expanse of land, 100–200 km away from the coast shows stronger iodine enrichment than inland areas (Davies, 2010). Highlands prevent the transport of iodine inland; this explains the decline in iodine concentration in the continental interiors of Africa, especially in mountainous areas of East Africa. However, volcanic mountains are usually rich in iodine; but leaching in the lee sides of high-altitude areas has caused acute depletion of the iodine content of soils. This is pronounced in the Kerio District in the Kenyan Rift Valley which has high prevalence of goiter and other related conditions collectively known as Iodine Deficiency Disorders, IDD (Davies, 2010).

As an evidence, traverses of the Moroccan coast show that the expanse of land, 100–200 km away from the coast shows stronger iodine enrichment than inland areas.<ref name=Dvies /> Highlands prevent the transport of iodine inland; this explains the decline in iodine concentration in the continental interiors of Africa, especially in mountainous areas of East Africa. However, volcanic mountains are usually rich in iodine; but leaching in the lee sides of high-altitude areas has caused acute depletion of the iodine content of soils. This is pronounced in the Kerio District in the Kenyan Rift Valley which has high prevalence of goiter and other related conditions collectively known as Iodine Deficiency Disorders, IDD.<ref name=Dvies />

Iodine Deficiency Disorders (IDD) includes goiter (enlargement of the thyroid gland), cretinism (mental retardation with physical deformities), reduced IQ, miscarriages and birth defects (Davies, 2010). Although IDD has been recognized as a serious problem in several areas in Africa, Kerio District ranks first, with 72% of children in this region living with goiter (Davies, 2010).

Iodine Deficiency Disorders (IDD) includes goiter (enlargement of the thyroid gland), cretinism (mental retardation with physical deformities), reduced IQ, miscarriages and birth defects.<ref name=Dvies /> Although IDD has been recognized as a serious problem in several areas in Africa, Kerio District ranks first, with 72% of children in this region living with goiter.<ref name=Dvies />

To curtail IDD, salt iodization programme has been introduced, not only in this region but in all African countries. However, this project has not yielded maximum results due to the counteracting effect of goitrogens in the African diet. Goitrogenic effect comes from certain vegetables such as brassica. It proceeds by depressing the formation of thyroid hormone leading to increased secretion of thyroid stimulating hormone (TSH). The thyroid gland responds to this by enlarging itself as a compensating mechanism leading to the development of goiter ([[:File:UNN_Medical_Geology_Fig_6.png|Figure 6]]) (Davies, 2010). Another substance with goitrogenous effect is thiocyanate which is present in cassava consumed in many African countries. It inhibits the entrance of iodine into the thyroid gland (Davies, 2010).

To curtail IDD, salt iodization programme has been introduced, not only in this region but in all African countries. However, this project has not yielded maximum results due to the counteracting effect of goitrogens in the African diet. Goitrogenic effect comes from certain vegetables such as brassica. It proceeds by depressing the formation of thyroid hormone leading to increased secretion of thyroid stimulating hormone (TSH). The thyroid gland responds to this by enlarging itself as a compensating mechanism leading to the development of goiter ([[:File:UNN_Medical_Geology_Fig_6.png|Figure 6]]).<ref name=Dvies /> Another substance with goitrogenous effect is thiocyanate which is present in cassava consumed in many African countries. It inhibits the entrance of iodine into the thyroid gland.<ref name=Dvies />

In China, about 425 million people are at risk of IDD. In iodine deficiency areas, a serious shortage of iodine intake by pregnant women would affect the development of the nervous system of the fetus and newborn infants would likely suffer from cretinism and related health problems (Zheng et al, 2010). Endemic cretinism prevailed in Chinese regions with acute iodine shortage. Analysis showed that places with iodine threshold of 25μg suffer from endemic cretinism whereas places with only goiter usually have iodine threshold of 50 μg. This triggered off a research into the relationship between goiter and cretinism in 25 provinces on 750,000 persons. The research showed that goiter had an average prevalence rate of 24.92% while cretinism had an average prevalence rate of 3.15% (Zheng et al, 2010). Fortunately, inhalation of iodine volatized from coal has contributed to increased reduction in the goiter cases.

In China, about 425 million people are at risk of IDD. In iodine deficiency areas, a serious shortage of iodine intake by pregnant women would affect the development of the nervous system of the fetus and newborn infants would likely suffer from cretinism and related health problems (Zheng et al, 2010). Endemic cretinism prevailed in Chinese regions with acute iodine shortage. Analysis showed that places with iodine threshold of 25μg suffer from endemic cretinism whereas places with only goiter usually have iodine threshold of 50 μg. This triggered off a research into the relationship between goiter and cretinism in 25 provinces on 750,000 persons. The research showed that goiter had an average prevalence rate of 24.92% while cretinism had an average prevalence rate of 3.15% (Zheng et al, 2010). Fortunately, inhalation of iodine volatized from coal has contributed to increased reduction in the goiter cases.

Deficiency of selenium manifests as a disease known as Keshan disease– a disease that occurs due to the deterioration of the heart muscle leading to chronic cardiomyopathy. Generally, WHO (1987, 1996) recommended a daily Se intake of 30 μg of selenium for females and 40 μg of selenium for males. Excess concentration of Se in the body results in garlic scent from the mouth and skin (due to the formation of dimethyl selenide), hair loss, nail fragility, edema of the lungs, malfunctioning of the liver, redness of the skin, rhinitis and bronchoalveolitis (Fordyce, 2010).

Deficiency of selenium manifests as a disease known as Keshan disease– a disease that occurs due to the deterioration of the heart muscle leading to chronic cardiomyopathy. Generally, WHO (1987, 1996) recommended a daily Se intake of 30 μg of selenium for females and 40 μg of selenium for males. Excess concentration of Se in the body results in garlic scent from the mouth and skin (due to the formation of dimethyl selenide), hair loss, nail fragility, edema of the lungs, malfunctioning of the liver, redness of the skin, rhinitis and bronchoalveolitis (Fordyce, 2010).

In living systems, selenium occurs as selenocysteine and is incorporated in two enzymes, namely: glutathione peroxidase and 1 5'-iodothyronine deiodinase. These enzymes are important in the thyroid gland where they help in thyroid hormone production. Glutathione peroxidase protects cells against oxidative damage by acting as a catalyst in the breakdown of hydrogen peroxide. According to Davies (2010) thyroxine is broken down to triiodothyronine–an important thyroid hormone– through deiodination catalysis by iodothyronine deiodinase. These hormones –triiodothyronine and thyroxine– contain iodine. So selenium and iodine are involved in the formation of thyroid hormone. It follows, therefore, that combined iodine and selenium deficiencies affect the metabolism of thyroid hormone leading to increased rate of IDD. This explains the reason for the severity of IDD in Central Africa and Democratic Republic of Congo as both countries have low concentrations of selenium and iodine in their soils.

In living systems, selenium occurs as selenocysteine and is incorporated in two enzymes, namely: glutathione peroxidase and 1 5'-iodothyronine deiodinase. These enzymes are important in the thyroid gland where they help in thyroid hormone production. Glutathione peroxidase protects cells against oxidative damage by acting as a catalyst in the breakdown of hydrogen peroxide. According to Davies<ref name=Dvies /> thyroxine is broken down to triiodothyronine–an important thyroid hormone– through deiodination catalysis by iodothyronine deiodinase. These hormones –triiodothyronine and thyroxine– contain iodine. So selenium and iodine are involved in the formation of thyroid hormone. It follows, therefore, that combined iodine and selenium deficiencies affect the metabolism of thyroid hormone leading to increased rate of IDD. This explains the reason for the severity of IDD in Central Africa and Democratic Republic of Congo as both countries have low concentrations of selenium and iodine in their soils.

====Health benefits of selenium====

====Health benefits of selenium====

The selenium-containing protein, glutathione peroxidase, competes for the human body system with HIV-1 and thus stops its replication in the body. However, according to Davies (2010), there is a particular selenium level in the body above which HIV-1 infection cannot occur. Below this level, the human body gets infected by HIV-1. The deficiency of selenium in the soil of southern African countries is the cause of high scourge of HIV-1. Selenium supplementation programmes would help in tackling this menace.

The selenium-containing protein, glutathione peroxidase, competes for the human body system with HIV-1 and thus stops its replication in the body. However, according to Davies,<ref name=Dvies /> there is a particular selenium level in the body above which HIV-1 infection cannot occur. Below this level, the human body gets infected by HIV-1. The deficiency of selenium in the soil of southern African countries is the cause of high scourge of HIV-1. Selenium supplementation programmes would help in tackling this menace.

Selenium has other health benefits as follows:

Selenium has other health benefits as follows:

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|+ Table 4: Possible Health Effects of Different Fluoride Concentrations in Drinking Water (Davies, 2010).

|+ Table 4: Possible Health Effects of Different Fluoride Concentrations in Drinking Water.<ref name=Dvies />

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! Concentration of Fluoride (mg/l) || Possible Health Effects

! Concentration of Fluoride (mg/l) || Possible Health Effects

Geologic materials that are characteristically rich in fluorine are organic clays and shales, carbonatites, phosphates, hydrothermal ores and silicic igneous rocks such as rhyolites, dacites and granites (Selinus et al, 2010).

Geologic materials that are characteristically rich in fluorine are organic clays and shales, carbonatites, phosphates, hydrothermal ores and silicic igneous rocks such as rhyolites, dacites and granites (Selinus et al, 2010).

Studies have shown that fluoride mineralization occurs in tectonically unstable areas such as zones of rifting and zones characterized by rise of fluoride from the lower crust or upper mantle. This explains why people living in the African Rift zones and volcanic areas have high concentration of fluoride in their natural water bodies. In the East African Rift, in particular, most of the lakes are contaminated by fluoride as a result of influx of fluoride from hot springs and volcanic gases (Davies, 2010). The lake with the highest fluoride concentration occurs in this area−Lake Nakuru in the Kenyan Rift Valley. According to Davies (2010), the water of this lake has fluoride concentration in the order of 2800 mg/l. Other African countries with high fluoride concentration in groundwater include granitic areas in Ghana and parts of Malawi and Tanzania while sedimentary areas with high fluoride concentration are found in parts of North Africa and Senegal in West Africa (Davies, 2010). Nigeria, Zimbabwe and Ethiopia had been hit by adverse health conditions triggered by nutritional fluoride imbalance (Davies, 2010).

Studies have shown that fluoride mineralization occurs in tectonically unstable areas such as zones of rifting and zones characterized by rise of fluoride from the lower crust or upper mantle. This explains why people living in the African Rift zones and volcanic areas have high concentration of fluoride in their natural water bodies. In the East African Rift, in particular, most of the lakes are contaminated by fluoride as a result of influx of fluoride from hot springs and volcanic gases.<ref name=Dvies /> The lake with the highest fluoride concentration occurs in this area−Lake Nakuru in the Kenyan Rift Valley. According to Davies,<ref name=Dvies /> the water of this lake has fluoride concentration in the order of 2800 mg/l. Other African countries with high fluoride concentration in groundwater include granitic areas in Ghana and parts of Malawi and Tanzania while sedimentary areas with high fluoride concentration are found in parts of North Africa and Senegal in West Africa.<ref name=Dvies /> Nigeria, Zimbabwe and Ethiopia had been hit by adverse health conditions triggered by nutritional fluoride imbalance.<ref name=Dvies />

===Health effects of Cadmium, Cd===

===Health effects of Cadmium, Cd===

Radon is a colourless inert gas formed from the radioactive disintegration of radium –the radioactive daughter of uranium. It has been established that there is a link between the levels of radon emitted by the rocks and that emitted by soils. The level of radon emitted by any rock depends on the quantity of uranium it contains which occurs in association with other minerals such as gold, phosphate and copper. This explains the scourge of lung cancer amongst uranium miners, as radon is carcinogenic. Radon emitted from most rocks travel to the surface through fractures and faults (Finkelman et al, 2010b). Its movement into buildings occurs through foundation cracks, cracks in the floor and walls below and above the surface. It can also enter through gaps in timber floors and around pipe fittings ([[:File:UNN_Medical_Geology_Fig_10.png|Figure 10]]).

Radon is a colourless inert gas formed from the radioactive disintegration of radium –the radioactive daughter of uranium. It has been established that there is a link between the levels of radon emitted by the rocks and that emitted by soils. The level of radon emitted by any rock depends on the quantity of uranium it contains which occurs in association with other minerals such as gold, phosphate and copper. This explains the scourge of lung cancer amongst uranium miners, as radon is carcinogenic. Radon emitted from most rocks travel to the surface through fractures and faults (Finkelman et al, 2010b). Its movement into buildings occurs through foundation cracks, cracks in the floor and walls below and above the surface. It can also enter through gaps in timber floors and around pipe fittings ([[:File:UNN_Medical_Geology_Fig_10.png|Figure 10]]).

African countries that have uranium as a natural resource include: South Africa which has the largest deposit of uranium in the continent–241,000 metric tons, Niger, Namibia, Gabon, Algeria, Botswana, Central African Republic, Chad. Others are: Egypt, Nigeria, Morocco, Mali, Madagascar, Malawi, Togo, Tanzania, Mauritania, Somalia, Guinea, Zambia and Lesotho (Davies, 2010).

African countries that have uranium as a natural resource include: South Africa which has the largest deposit of uranium in the continent–241,000 metric tons, Niger, Namibia, Gabon, Algeria, Botswana, Central African Republic, Chad. Others are: Egypt, Nigeria, Morocco, Mali, Madagascar, Malawi, Togo, Tanzania, Mauritania, Somalia, Guinea, Zambia and Lesotho.<ref name=Dvies />

===Health effects of geogenic dust===

===Health effects of geogenic dust===

====Health effects of silica====

====Health effects of silica====

Silica is an important component of diatomites–a resource mined and produced in Kenya, Ethiopia, Algeria and South Africa (Davies, 2010). It is used in the manufacture of fillers, filters and may be used in making mild abrasives.

Silica is an important component of diatomites–a resource mined and produced in Kenya, Ethiopia, Algeria and South Africa.<ref name=Dvies /> It is used in the manufacture of fillers, filters and may be used in making mild abrasives.

Silica dust can be inhaled at quarries and at diatomite mines. It is most dangerous at the stage of calcining resulting to silicosis. It also affects people that live near the mine and processing plants. Worst of all, silicosis is contagious. In addition, its deposition in the lung is proven to cause fatal lung cancer (Selinus et al, 2013).

Silica dust can be inhaled at quarries and at diatomite mines. It is most dangerous at the stage of calcining resulting to silicosis. It also affects people that live near the mine and processing plants. Worst of all, silicosis is contagious. In addition, its deposition in the lung is proven to cause fatal lung cancer (Selinus et al, 2013).

====Geophagy for cultural reasons====

====Geophagy for cultural reasons====

In some African cultures, clays and soils are eaten so as to reaffirm the eaters’ bond with the ancestors, blood, grave and fertility (Davies, 2010). This practice is common amongst the Luo tribe of western Kenya where women of reproductive age eat soil to ‘improve fertility’. Here soil from termite moulds is preferred because of its red colour which represents blood. In this tribe, boys stop eating soil just to ‘become men.’

In some African cultures, clays and soils are eaten so as to reaffirm the eaters’ bond with the ancestors, blood, grave and fertility.<ref name=Dvies /> This practice is common amongst the Luo tribe of western Kenya where women of reproductive age eat soil to ‘improve fertility’. Here soil from termite moulds is preferred because of its red colour which represents blood. In this tribe, boys stop eating soil just to ‘become men.’

====Nutritional reasons for indulging in geophagy====

====Nutritional reasons for indulging in geophagy====

   

   

*  

*  

* Christine, L.E., Sujuan, G., Yiming, L., Chaoke, L., Rongdi, J., Kathleen, S.H., Jingxiang, C., Feng, M., Yunpeng, W., Po, Y., Shuzhuang, S., Frederick, W.U., Charles, W.S. and Hugh, C.H., 2000. Trace Element Levels in Drinking Water and Cognitive Function among Elderly Chinese. American Journal of Epidemiology, 151(9), 913-920.

*  

* Davies, T.C., 2010. Medical Geology in Africa. In: Selinus, O., Finkelman, R.B. and Centeno, J.A., (eds) 2010. Medical Geology: A Regional Synthesis, 199–216.

*  

* Finkelmana, R.B., Belkin, H.E. and Zheng, B., 2010. Health Impacts of Domestic Coal Use in China. Proceedings National Academy of Science, (USA), 96, 3427-3431.

* Finkelmana, R.B., Belkin, H.E. and Zheng, B., 2010. Health Impacts of Domestic Coal Use in China. Proceedings National Academy of Science, (USA), 96, 3427-3431.

* Finkelman, R.B., Centeno, J.A., and Selinus, O., 2005. The Emerging Medical and Geological Associations. Transactions of the American Clinical and Climatological Association, 116, 155-165.

* Finkelman, R.B., Centeno, J.A., and Selinus, O., 2005. The Emerging Medical and Geological Associations. Transactions of the American Clinical and Climatological Association, 116, 155-165.