Bio tools to detect asernic level in area

Yo people!Today topic will be : bio tools available to detect/survey the amount of asernic in an area.

How monitoring of arsenic was done?

Monitoring arsenic in ground water should be planned nationally.

1. Random testing of tube wells throughout the country to determine the extent of the problem.

2. Subsequently, blanket testing of all wells in selected districts should follow, to identify each and every contaminated well.

3. Blanket testing programmes could also include other activities that are essential for additional monitoring and management operations, such as

•  The location of each well using a Geographic Information System (GIS)
• The diagnosis of arsenicosis patients in the district surveyed
• The introduction of various water treatment measures in that district.

Blanket testing system

picture extracted from: http://www.wichitech.com/images/blankettestsystem.jpg

Geographic Information System (GIS)

Picture extracted from: http://advanced.jhu.edu/media/images/environmental/map_dem_gis_3d_b.jpg

These large scale monitoring methods have  help to detect the amount of arsenic in the area where further actions can be taken .

Knowledge about arsenic detection

Arsenic is commonly found throughout the environment in a wide array of chemical species that vary in toxicity and mobility. Many of these chemical species can be transformed due to biological activity or other changes in the environment, such as a change in oxidation-reduction potential and pH. This prospect for natural environmental change creates the possibility that a wide variety of arsenic species are constantly transforming at any time.


To determine the potential transformation and risk of arsenic in the environment for remedy decisions, the analysis of environmental samples should include identifying and quantifying both the total quantity of arsenic present and the specific chemical forms present, a procedure known as speciation.

However, speciation by a laboratory is expensive and the sample collection methods to ensure the preservation of in situ conditions are difficult and expensive.

The main species of arsenic found in the environment are the arsenic (III) and arsenic (V) oxyacids. Arsenates, arsenate anions, along with neutral arsenite constitute the main targets for field analytical assays.

In contaminated soils, inorganic arsenate is the predominant species.

In general, the arsenate and other arsenic (V) species are immobilized on geologically available surfaces, usually as iron oxides. Although arsenic (V) compounds are considered a low risk, bacterial and other environmental activities can readily convert them back into more mobile and more toxic forms of arsenic.

Groundwater and soil also contain organoarsenic species. In general organoarsenic compounds are less toxic than their corresponding oxyacids. Although usually found in lower concentrations, under the right conditions, they can be found in very high concentrations. In freshwater lakes, methylated arsenic can make up to 60% of the total arsenic. There are also arsenic sulfur species that constitute a sizable portion of arsenic geology and reducing environments in sediment and in solution. Although all of these species are not as common or currently believed to be as toxic as arsenic oxyacids they constitute a sizable fraction of the naturally occurring arsenic and should be a target in field measurements.

Case study: Bangladesh affected by arsenic

Knowing more about arsenic, we will now look at a case study of Bangladesh to showcase the seriousness of arsenic poisoning to humans’ health.

Picture extracted from: http://www.bdix.net/sdnbd_org/world_env_day/2002/current_issues/arsenic/maps/arsenic.gif

High level of arsenic contamination can be observed in Bangladesh with more than 20 % of the total land contains arsenic of concentration more than 50 μ g/ L as depicted from the picture.

History…

For the past two decades the water from over a million tube-wells has been slowly poisoning Bangladeshi villagers with naturally occurring arsenic. Over 18 million people are drinking this poisoned water daily.

Arsenic is naturally occurring in pyrite bedrock underlying much of West Bengal. The poisoning began to occur as millions of kiloliters of water were being pumped out from deep within underground reservoirs for more water resources. As a result, the water level dropped and exposed the arsenic-bearing pyrite to air leading to oxidisation, a reaction which flushed arsenic into the remaining water, contaminating them with arsenic compounds. This has lead to a large numbers of clean wells to be contaminated and expose more people to arsenic poisoning.



In the 1970’s, villagers in Jampukkur started to notice dark spots spread across their bodies; not knowing exactly what was actually causing it. Until 1993 did the villagers learned that they were drinking arsenic contaminated water with 95% of the village wells being contaminated.

Not only did arsenic take away millions of life in Jampukkur, it has also leaved citizens in tremors and pain. More reports of broken marriage surfaced when husbands send disfigured wives back to their parents for the fear that their wives disfigure is cause by arsenic poisoning. In Jampukkur, literally no young men and women get married at all. People believe that arsenic poison can be passed on from the parent to child, leading to many arsenic poisoned women having problems finding husbands.

Some scientists hypothesize that Bangladesh's problem is caused by local water chemistry. Others suggest it is because of the way vegetation decomposes in the monsoon cycles of wet and dry periods, which affect levels of oxygen in ground water.


And local factors enhance the impact of the poison, including a poor diet and addiction to chewing intoxicating betel palm seeds.

Prevention is the only solution, because there is no satisfactory treatment to arsenic poisoning, say experts.

Pumping water at Bangladesh well

So….do you wish to be the next victim of arsenic? !

Picture extracted from: http://serc.carleton.edu/images/health09/arsenic_poisoning.jpg

understand whats arsenic and how it affect us

Hi people. =) In this post, we will be sharing with you all some information about arsenic and how it enters our water supply.


SO What’s ARSENIC?

Picture extracted from: http://www.unesco-ihe.org/var/ihe/storage/images/media/images/projects/arsenic_minerals/15333-1-eng-GB/arsenic_minerals_reference.jpg

Arsenic is actually a metalloid element that belongs to the nitrogen group.It’s widely distributed in the earth’s crust with only a trace amount in all rock, soil and air. Concentration of arsenic in ground may be higher in certain areas due to weathering and anthropogenic activities such as metal mining, smelting, fossil fuel combustion and pesticide uses.

Arsenic can occurs in crystalline, power, amorphous or vitreous forms.Being toxic in nature, Arsenic is more toxic in its inorganic form than its organic form.It’s invisible, tasteless and odorless when present in water, which put people off guard when they drank water containing arsenic.Lastly, arsenic can be found in more than 200 mineral species.



Health impacts of arsenic in water bodies

Picture extracted from: http://www.siliconeer.com/past_issues/2000/may_00_arsenic_3.jpg

Arsenic in drinking water causes bladder, lung and skin cancer, and may cause kidney and liver cancer. Studies have also found that arsenic can harm the central and peripheral nervous systems, as well as heart and blood vessels, and causes serious skin problems. It may also cause birth defects and reproductive problems-National Academy of Sciences.


How arsenic gets into our water bodies?

Picture extracted from: http://www.blog.thesietch.org/wp-content/uploads/2009/03/dirty-water.jpg

Arsenic can either enters water supplies through natural deposits in the earth’s crust or from industrial and agricultural pollution. As arsenic is widely used in industry and agriculture processes, this rises the chance of the water bodies been contaminated with arsenic.Beside that, arsenic is also a by product of copper smelting, mining and coal burning.


In the next post we will be discussing further about the impact of arsenic to human, with bangladesh as our case study.

Stay tune!for more intersting knowledge =)!

Welcome to our blog~!

Welcome to our blog on environmental monitoring and control!

The first topic that we will be discussing will be ARSENIC.

In countries where clean drinking water is scarce, people tend to have a higher exposure to water that are contaminated.One of these contaminents in water bodies is arsenic.

So have youall wonder how arsenic, a naturally-occuring metal in ground enters our water bodies?

Stay tune to our blog to find out more about the impact of arsenic and modern technologies used to detect and monitor arsenic!