Water, Our Health and Bangladesh
Drinking water is water that is clean and safe for humans to drink and to use other domestic purposes such as cooking, washing up, bathing and showering. The human body is made up of 60-75% water; therefore drinking enough water is essential to maintain our health. Water helps to relieve or prevent headaches, constipation and assist in digestion. It further helps maintaining weight loss (water is calorie free) and keeping the kidneys healthy. To keep us healthy we should drink at least the minimum of eight glasses of water per day or 1.5-2.5 litres per day.
Bottled water in recent times has been very popular to consumers due to the convenience of being able to it carry around. Tap water is the main source of drinking water in cities and rural towns. Australian tap water is safe to drink and Melbourne water is regarded as one of the best drinking water in the world.
We can use either bottled water or tap water for drinking, but which water is healthier? Bottled water is not subject to rigorous testing and purity standards that is applied to city tap water (eg. WHO, Australian WQ Guidelines, USEPA). On the other hand, tap water is regularly tested for common contaminants (eg. microbial pathogens), inorganic contaminants (eg. arsenic, nitrate, lead) and organic contaminants (eg. atrazine, pesticides). Chemicals such as fluoride are added in tap water to prevent tooth decay and chlorine as disinfectant. Research studies carried out have not found any significant differences in terms of health benefits between bottled water and tap water, although bottled water is about 1000 times more expensive than tap water (based on per unit of water). Nevertheless, bottled water may be an alternative option where tap or shallow tube well water is contaminated.
Until recently, Bangladesh rural communities depended on shallow tube wells as a major source of drinking water. However, due to contamination of these tube wells with arsenic it has been suggested to use surface water for drinking. Unfortunately villagers in Bangladesh may still be using ponds and rivers water for drinking and other purposes. There are potential risks in using surface water for drinking and other domestic usages as it may possibly be contaminated with human and animal pathogens and could be a source of water borne infectious diseases such as cholera. In addition, a recent research reported that Bangladesh surface water at some places is also contaminated with toxins producing cyanobacteria (called cyanotoxins). These cyanotoxins is a potential hazard to public health as it may cause liver damage or even human death.
A group of molecular and microbiologists from the U.S.A found that filtering surface water through an old sari cloth (by folding four to eight times) can prevent cholera in Bangladesh (see Figure 1). Other scientists further believe that the same technique (i.e. use of old sari cloth) may also be useful in filtering out cyanobacteria. Solar Water Disinfection (SODIS) technique that uses sunlight (UV-A and increased temperature) can also be used to treat small quantities of contaminated water. Here contaminated water is filled into transparent plastic bottles and exposed to full sunlight for at least six hours to destroy micro organisms that cause water borne diseases.
1 : A Bangladeshi woman prepares to filter drinking water with an old sari cloth
source : Proceedings of the National Academy of Sciences, USA)
Choice (2005) : Report-Bottled water - A triumph pay for bottled water if you like the taste, but donot kid yourself its healthier than tap water
Colwell et al. (2003). Reduction of cholera in Bangladeshi villages by simple filtration. Proceedings of the National Academy of Sciences. USA On line February 4, 2003, vol 100 (3) : 1051-1055.
WHO (2004) : Occurrence of cyanobcterial toxins (Microcystins) in surface waters of Rural Bangladesh-Pilot study. WHO/SDE/WSH/04.06. Geneva
information was compiled by Golam Kibria, Ph.D in February
2006 for http://www.sydneybashi-bangla.com/
. Views expressed in this article are those of the author and are not to be
taken to be the views of any others including third parties. The author
disclaims any liability for any error, loss or other consequences which may
arise from relying on any information in this article.
Dr Golam Kibria is a Senior Environmental Scientist with the Australia’s
largest Rural Water Authority and based in Victoria