5. Water Quality and Public Health

1. 5. Water Quality and Public Health Mac Marshall Faculty Advisor: Steve Taylor, PhD INTRODUCTION HEALTH CONNECTION ABSTRACT The distribution of the total volume of water on earth is evident. It can be seen that 96.5% of the worlds water resource is the water of our oceans and seas. About 2.5% is low mineral water, which is of the greatest interest to mankind. Of this amount of low-mineral water, 70% is accumulated in the ice of the Arctic and Antarctica and glaciers of Asia, North America and Europe. About 30% of low-mineral water occurs in the form of groundwater in permeable rocks and soil as very important temporary reservoirs of atmospheric precipitation. Only .006% of all low mineral water falls on terrestrial surface water resources, lakes, swamps, and riverbeds (Fig. 2). Water is one of the most important resources on this planet, without it life wouldn’t exist. The hydrosphere forms the foundation of the critical zone near the Earth’s surface, in which biologic organisms flourish. The global demand for potable water is increasing while the availability and quality is decreasing. Hence, freshwater environments are of major importance to human health in both direct and indirect ways. This project examines geologic variables that influence water quality around the world and its epidemiological effects. A case study of groundwater quality from the Makutuapora in the Dodoma region of central Tanzania reveals a relationship between mineral-water interactions, water chemistry, bedrock geology, and microbiology. The natural geological and geochemical environments, in addition to providing beneficial elements that support plant growth, may also give rise to undesirable or toxic properties through deficiencies or anomalous excess. The significance of water for health has been known for a very long time. Hippocrates recommended bathing as the most effective measure of protection against many diseases. The health significance and role of water is reflected in the fact that a supply of hygienically good water in adequate amounts improves living conditions, raises the level of public health, and reduces morality. In this way, it directly increases the length and quality of life. Classical medical science and practice and current medical postulates based on them indicate that the supply of drinking water is closely correlated with the danger of infectious intestinal diseases. Water shortage in human organisms increases osmolarity of the intestinal contents and threatens equilibrium of the processes of absorption and secretion of water and fluids from the lumen to the blood vessels, this causes thirst. If water loss is not compensated in time, all health parameters deteriorate due to disturbance of physiological processes, and death occurs with loss of 10-20% of total fluids. The epidemiological role of water in transmission and spreading of infectious diseases today is well known. Here are some examples: Cholera, Typhoid Fever (Fig. 3), Bacteria Dysentery, Poliomyelitis, Coxsackie (Fig. 4), and Hepatitis. solid load was greater during the wet season. Most of the groundwater were above pH 7. In the dry season the higher salinity reduces water quality and would be a major factor in determining use of water resources from individual wells. The physiological status of the community varies. This is undoubtedly related to variations in the physicochemical and nutrient conditions encountered by the bacteria at the sites. There was considerable contamination of the groundwater's by thermo tolerant coli forms suggesting a significant health risk from enteric pathogens in the groundwater's. Metals in the water are largely in a particulate, possibly colloidal from. The increase of metals suggest an imbalance in the stead-state reactions between groundwater's and magmatic minerals. Fig. 2 Precipitation on Earth Fig. 5 GEOLOGICAL PROCESS CONCLUSIONS Composition of water can depend on the pH, water with a high pH occur in hyper alkaline springs with ultra basic rock terrains, whereas water with low pH occur in acidic environments associated with the oxidations of iron sulphides in soils and bedrocks. Pollutants from urbanization, industry, and agriculture can change the net balance of the components. Natural geologic environment may also introduce harmful substances to groundwater's used for drinking purposes, an example of this is arsenic. Despite major advances in science and management, maintaining and improving the environment will require better understanding of the processes. Environmental quality and health issues must be tackled within an integrated framework of environmental science and management, economics, politics, law and history. Groundwater makes up over 95% of the worlds available freshwater resources and is the main source of drinking water for a large percentage of the world’s population. We must keep an abundant supply of water available for our populations to maintain good health since water is key to most all things here on earth. Fig. 3 Typhoid Fever Fig. 4 Coxsackie CASE STUDY Recent research has highlighted the high concentrations of potentially toxic elements in African groundwater's. (Ogbunkagu, 1996) Groundwater, sediment, soil and rock samples were collected in two field seasons in 1992: April-May (wet season) and October-November (Dry season). Thirty-two sites were sampled comprising of eight surface water sites, 11 shallow sites, and 13 deep groundwater sites (Fig. 5). Africa is a tropical region where rocks weather more quickly and leaching is more intense than temperate zones. The Dodoma area consists of migmatitic gneisses, amphibolites, feldspathic quartzite's, and quartz-feldspathic gneisses. In general surface waters were weakly alkaline, at ambient temperature and had a high total dissolved solid concentration. The particulate REFERENCES • Bowell, 1996, Biogeochemical factors affecting groundwater quality in Tanzania, IN: J.D. Appleton, R. Fuge & G.J.H.McCall (ed), Environmental geochemistry and health: with special reference to developing countries. London: Geological Society of London (Special Publication no.113) • Edmunds, W.M. and Smedley, P.L., 1996, Groundwater geochemistry and health: an overview: IN: J.D. Appleton, R.Fuge & G.J.H.McCall (ed), Environmental geochemistry and health: with special reference to developing countries. London: Geological Society of London (Special Publication no.113) p.91-105 • Komatina, 2004, Chapter 3-Other Natural (Environmental) Factors (water resources) • Neal, 2003, Surface and Groundwater Quality and Human Health- Overview, in Skinner and Berger • Rubenowitz and Hiscock, 2005, Water Hardness and Health, in Selinus, 2005 • Ogbukagu, I. K. 1984. Hydrology of groundwater resources of the Aguta area, SE Nigeria. Journal of Africa Earth Science, 2, 109-117. Fig. 1 Population Growth & Water Withdrawals CONTACT Mac Lee Marshall Dept. of Earth and Physical Science mmarshall06@wou.edu