BY ASMA ISHTIAQ,
Lives of about 70 million people of Pakistan are at stake due to drinking water polluted with Arsenic.
Arsenic is one of the most common inorganic contaminants found in drinking water worldwide. Normally, arsenic stays in the ground but in last few decades, South Asian countries have been pumping enormous volumes of groundwater which is causing the problem. Global permissible limit of arsenic in water is 10 ppm whereas in Pakistan it is 50ppm.
The cause of the contamination is natural. Arsenic leaches out of rocks and sediments, with small quantities becoming dissolved in groundwater as a result of weathering. The inorganic salts of arsenic are totally tasteless and odorless, yet extremely toxic to humans in its inorganic form. Fish, shellfish, meat, poultry, dairy products and cereals can also be dietary sources of arsenic, although exposure from these foods is generally much lower compared to exposure through contaminated groundwater
If consumed over long periods, even low concentrations, it can cause, cardiovascular diseases, neurodevelopmental delays, thickening of the skin, darker skin, abdominal pain, diarrhea, numbness, and cancer. Arsenic exposure affects virtually all organ systems including the cardiovascular, dermatology, nervous, hepatobiliary, renal, gastro-intestinal, and respiratory systems.
No access to clean water and infrequent government water supply makes the problem worse for Pakistan’s both urban and rural population even in the Capital. Capital of Pakistan, Islamabad is also facing this problem and is drowned in its consequences.
Government of Pakistan is well aware of this problem but no proper action has been taken by the government yet. The government needs to pay attention towards this poisonous problem or this will become a major catastrophe.
We want Government to take some action but till then we must prevent this problem and do whatever it takes from atleast our side.
Prevention and control
There are a number of options to reduce levels of arsenic in drinking-water.
Substitute high-arsenic sources, such as groundwater, with low-arsenic, microbiologically safe sources such as rain water and treated surface water. Low-arsenic water can be used for drinking, cooking and irrigation purposes, whereas high-arsenic water can be used for other purposes such as bathing and washing clothes.
Discriminate between high-arsenic and low-arsenic sources. For example, test water for arsenic levels and paint tube wells or hand pumps different colours. This can be an effective and low-cost means to rapidly reduce exposure to arsenic when accompanied by effective education.
Blend low-arsenic water with higher-arsenic water to achieve an acceptable arsenic concentration level.
Install arsenic removal systems – either centralized or domestic – and ensure the appropriate disposal of the removed arsenic. Technologies for arsenic removal include oxidation, coagulation-precipitation, absorption, ion exchange, and membrane techniques. There is an increasing number of effective and low-cost options for removing arsenic from small or household supplies, though there is still limited evidence about the extent to which such systems are used effectively over sustained periods of time.
Long-term actions are also required to reduce occupational exposure from industrial processes.
Education and community engagement are key factors for ensuring successful interventions. There is a need for community members to understand the risks of high arsenic exposure and the sources of arsenic exposure, including the intake of arsenic by crops (e.g. rice) from irrigation water and the intake of arsenic into food from cooking water.
High-risk populations should also be monitored for early signs of arsenic poisoning – usually skin problems.
Recently, a team of Pakistani researchers has successfully developed a cost effective technology to clean poisonous arsenic in drinking water through watermelon rind. This filter proved to be effective to clean the water from arsenic by up to 95 percent.
(Writer is a student of BS (Hons) Environmental Sciences, Bahria University Islamabad)
BY ASMA ISHTIAQ,