An increase of population and growth in economic development is causing adverse reactions with the surrounding environment of many areas. This population growth is responsible for changing the natural landscape and is also releasing a variety of pollutants. The combination of human-introduced chemicals, as well as those that occur geologically, have caused toxic elements to become more abundant and pose increased health risks. These pollutants can be studied using geochemical analysis of a given area, a combination of geological and chemical techniques applied in the context of public health. The chemicals found in the Earth have been directly linked to a multitude of health problems ranging in scale from allergies to cancer fatalities. Even minimal exposures over long periods of time can have adverse effects by allowing toxic elements, such as arsenic, to build up in the body. By taking the proper steps in monitoring geochemical parameters in the environment, it is possible to mitigate exposure and reduce health risks. This paper examines a variety of techniques that are used to determine the level of potentially dangerous chemicals occurring in the hydrosphere and geosphere. This work is placed in the context of case studies associated with agricultural and forestry practices. 8. Applied Geochemistry as a Tool in Medical Geology Dan Dziekan, Earth and Physical Sciences Department Western Oregon University Exposure to elements, both harmless and toxic, can result in health issues ranging from simple allergies, to fatalities. Different elements cause different health concerns (Table 3), the level of exposure as well as the time exposed relates to the impact the element has on the body. An atlas of Slovak Republic was published in 1997 outlining the geology of the area. In this atlas was a legend referring water samples taken all across the area. This legend shows the level of contaminants found in the water table all across the Slovak Republic (Komatina 2004). Iron is a common element found in the human body, in some cases it can reach toxic levels. The body has no natural way to control iron excretion. It can build up in excess from dietary supplements as well as leaching from iron containers. The link of excess iron and heart disease is currently being reviewed (Centeno et al. 2005). A medium is a vehicle by means of which exposure occurs (Fowels et al. 2005). This medium can take the form of anything that plants and animals come into contact with (Table 1). After coming into contact with the medium, the chemical then makes its way through the human body (Table 2) until it is excreted. Contact with the medium can be linked to human interactions, such as a gas leak, or natural hazards, such as a tsunami. Lead particles from lead based paint can be ingested with house dust, and transported to the brain, where it exerts its neurotoxic effect (Fowels et al. 2005). When a flood happens it has the potential to wipe out entire towns. This will have a severe impact on the economy as well as the health of the citizens (Fowels et al. 2005). Geochemistry is a very significant aspect in modern health studies. It includes a wide array of health problems that are very common and those that are less common. It is important to study geochemistry in order to better understand the root cause of many health issues that are affecting people worldwide, and to develop preventative methods to ensure that these health issues never reach the population. Hazardous chemicals and naturally occurring elements are becoming more abundant in many places around the world. This is partially due to an increase in human activity (Plant et al. 2003). There are two types of chemical elements: those that are essential to life, and those that are potentially harmful (Plant et al. 2003). Plants and animals are exposed to many of these elements on a daily basis, but due to the low levels of exposure they are mostly unaffected. The toxins that are causing problems can all be found naturally occurring, due to human processes though, these toxins are increasing in number (Plant el al. 2003). This increase in the levels of elements found in the environment means that elements that were previously harmless are now found in such abundance that they pose a greater health risk (Plant et al. 2003). These potentially harmful elements can be found everywhere in the world now, in the; air, water, soil, and food (Table 1) (Fowels et al. 2005). IntroductionEnvironmental Impacts Centeno et al., 2005, Environmental Pathology, in Selinus, 2005 Fowles et al., 2005, Environmental Medicine, in Selinus, 2005 Komatina, 2004, Chapter 7-8 – Procedures and methods in Medical Geology Plant et al., 2003, Global Environmental Geochemistry, in Skinner and Berger Conclusion Case Study Health Connection References Table 3. Table relating health effects to the group that is most sensitive to these effects as well as examples of chemicals that can cause the health effects. Abstract Table 1. Table showing environmental medium, health effects, and an example related to medical geology. Table 2. Outlining the pathway of a chemical from exposure to body response. Contact Information Dan Dziekan Western Oregon University