Water Scarcity and Global Health James L Regens

Water Scarcity and Global Health James L. Regens University of Oklahoma Health Sciences Center Environmental and Occupational Health Council Association of Schools of Public Health Environmental Health Conference 2009 June 12 -14, 2009

Overview n n n www. unhmagazine. unh. edu Availability of Water Resources Factors Influencing Water Scarcity Impacts on Global Health

§ § Imagine being unable to turn on the tap when you get thirsty Now, imagine having to carry water for hours each day to have water to drink Or, imagine pinching your nose as you drink to avoid the water’s foul odor And, imagine the real possibility that taking a drink of water exposes you to disease

Annual Water Withdrawals (m 3 per capita) Source: computed from World Bank data

Annual Renewable Water Resources (m 3 per capita) Source: computed from World Bank data

©IWMI, 2001 n n The threshold for ‘water stress’ is a per capita availability of 1700 m 3 of water for annual consumption For water scarcity the threshold is 1000 m 3 of water for annual consumption

n 40% of world’s population (3 B people) will live in countries classified as water stressed by hydrologists by 2015 http: //www. iucn. org n Even though 2. 4 B people got access to safe drinking water for first time during 1990 s, estimated 1. 7 B people still lack safe drinking water

n n Aral Sea (Central Asia) has 60% less water than 1975 Lake Chad (West Africa) is 1/20 th its 1970 s size http: //www. sptimes. com n A number of major rivers around the world including the Colorado, Rio Grande, Indus, and Yangtze no longer reach the sea consistently

Factors Influencing Water Scarcity http: //www. wmo. int § Hydrologic Cycle § Population Growth § Poverty § Use Patterns § Contamination

§ § World population increased 300% in 20 th century and use of water increased 700% Since 1950 the world population has doubled but water consumption has increased six-fold Water use will increase 50% over 2005 level by 2035 Approximately 2 M tons of human waste is released annually into rivers and streams around the globe

Impacts on Global Health http: //www. thespiritans. org n n n http: //www. apec-vc. org. cn About 1. 8 M people, mostly children, die annually from diarrhea and related diseases with many deaths preventable if water were not contaminated The combination of safe drinking water, adequate sanitation and good hygiene can reduce the number of deaths caused by diarrhoeal diseases by an average of 65% The simple act of washing hands with soap and water can reduce diarrhoeal diseases by over 40%

n n http: //www. nri. org n In many countries children, particularly girls as young as 10 years old, may take the main responsibility for drawing and carrying the family's water. The size of the water container may vary with the size of the child, but each liter of water carried weighs 1 kg and may need to be carried up to three or four miles Carrying such heavy weights is damaging in the long term for adult women, and for girls there are even more serious implications given their physical immaturity In particular, there can be damage to the head, neck and spine. In extreme cases deformity of the spine can lead to problems in pregnancy and childbirth

n http: //www. droitsenfant. com www. savesight. org n Malnourished children are more vulnerable to disease, especially diarrhea, pneumonia, measles and malaria. These four diseases, plus malnutrition, account for seven out of ten childhood deaths in developing countries. For example in Zambia, one in five children dies before their fifth birthday. A lack of water also means that children cannot wash often enough and suffer from diseases as a result. These include skin diseases like scabies and eye infections such as trachoma, the largest cause of preventable blindness in the developing world by regularly washing the face, hands, and eyes.

n n n http: //www. nri. org Cholera, a bacteria that lasts up to 3 weeks in soil, is spread by contaminated water and food and occasionally by person to person contact. Sudden large outbreaks usually are due to a contaminated water supply. Bacillary dysentery caused by exposure to Shigella bacteria from contaminated drinking water, food , or flies is contagious and more severe than amoebic dysentery. Approximately 140 M people are infected annually causing about 300 K deaths, mostly among children under the age of five. Typhoid fever is contracted when people drink water or eat food contaminated by Salmonella typhi bacteria found in human waste. It affects 17 M people worldwide annually, with approximately 600 K deaths. Typhoid fever has been virtually eliminated in developed countries.

www. globalriskawareness. com cartercenter. com § Bilharzia, caused by a small flat worm in the veins of pelvic organs, infects > 200 M people in 74 countries and causes 20 K deaths/year. Eggs are excreted when people go to the toilet. If the eggs reach a lake or stream to hatch into larva which are eaten by snails, the larva eventually are excreted into the stream or lake where they can infect new people. § Guinea worm, a long worm (≤ 1 m) that lives under the skin, enters through contaminated water and can be spread when infected skin is submerged in water, allowing larvae back into water. The number of cases has fallen by 97% from 3. 5 M to 150 K since 1990.

§ Malaria causes more that 300 M acute illnesses and over 1 M deaths annually § Developing safe drinking water supplies and ensuring the environment around water supplies and dwellings is clean reduces larval habitats

Key Internet Sites n n n World Health Organization (http: //www. who. int/) Consultative Group on International Agricultural Research (CGIAR) (http: //www. cgiar. org/) Desert Research Institute (http: //www. dri. edu/) Global Water Policy Project (http: //www. globalwaterpolicy. org/) International Arid Lands Consortium (http: //ag. arizona. edu/OALS/IALC/) International Center for Agricultural Research in Dry Areas (http: //www. icarda. org/) International Institute for Sustainable Development (http: //www. iisd. ca/process/forest_desertification_land. htm) Nature Conservancy (http: //nature. org/) United Nations Environment Programme (http: //www. unep. org/) United Nations Food & Agriculture Organization (http: //www. fao. org/) United States Geological Survey (http: //pubs. usgs. gov/) World Bank (http: //worldbank. org/)