TAG: GS 3: SCIENCE AND TECHNOLOGY
THE CONTEXT: Researchers from the Indian Institute of Science (IISc) have innovated a groundbreaking remediation process designed to remove heavy metal contaminants, including arsenic, from groundwater.
EXPLANATION:
- This novel method not only efficiently extracts these harmful substances but also ensures their environmentally sustainable disposal, addressing a critical gap in existing technologies.
The Problem of Heavy Metal Contamination
- Prevalence in India
- Heavy metal contamination in groundwater is a significant public health concern in India.
- Reports indicate that arsenic levels in 113 districts across 21 states exceed the permissible limit of 0.01 mg per liter, while fluoride levels in 223 districts across 23 states surpass the safe threshold of 1.5 mg per liter.
- These contaminants pose severe risks to both human and animal health, necessitating effective removal and safe disposal methods.
- Health Implications
- Arsenic and fluoride in drinking water can lead to numerous health problems.
- Chronic exposure to arsenic can cause skin lesions, cancer, cardiovascular diseases, and diabetes.
- High levels of fluoride can result in dental and skeletal fluorosis, conditions that severely affect bone structure and strength.
The Innovative Solution by IISc
- The IISc team has developed a three-step method for removing heavy metals from groundwater.
- This method is designed to address not only the extraction of contaminants but also their subsequent disposal in an eco-friendly manner.
- The process is currently patent-pending.
- Methodology
- Adsorbent Material Production:
- The manufacturing of the adsorbent material involves a straightforward and reproducible process, making it feasible for widespread use.
- The material is capable of binding with heavy metals, effectively removing them from contaminated water.
- Application and Operation:
- The system is simple to assemble and operate.
- In laboratory tests, a small pilot-scale adsorption column was able to produce safe drinking water, meeting WHO standards, for two individuals over three days.
- Sustainable Disposal:
- After the removal of heavy metals, the system ensures that these contaminants are disposed of in a sustainable manner.
- This prevents the re-entry of heavy metals into the environment, a critical improvement over existing methods that often result in untreated sludge being sent to landfills.
- Current technologies can effectively remove arsenic and other heavy metals from water.
- However, they often fail to address the disposal of the extracted contaminants adequately.
- The IISc method overcomes this by providing a sustainable disposal solution, ensuring that the heavy metals do not re-enter the groundwater.
- Adsorbent Material Production:
Deployment and Testing
- The IISc researchers have partnered with the INREM Foundation and Earthwatch, two non-governmental organizations, to deploy and test their system in rural areas.
- These collaborations have focused on regions such as Bhagalpur in Bihar and Chickballapur in Karnataka, where groundwater contamination is a pressing issue.
- Field tests have demonstrated the efficacy of the system in real-world conditions.
- The simple assembly and operation make it a practical solution for rural communities, ensuring access to clean and safe drinking water.
Heavy metals contamination places in India
- Heavy metal contamination is a significant environmental concern in India, affecting various regions and ecosystems.
- Here are some key places where heavy metal contamination has been reported:
- Bengaluru:
- Lalbagh Lake, Madiwala Lake, Hebbal Lake, Bellandur Lake, Kengeri Tank, and Arekere Lake are among the probable contaminated sites identified by the Central Pollution Control Board (CPCB).
- Soil and groundwater samples from areas like Goripalya and Peenya Industrial area have been found to be contaminated with heavy metals like copper, chromium, lead, and magnesium.
- Ganga River:
- The river contains high levels of lead, iron, nickel, cadmium, and arsenic, posing significant environmental and health risks.
- Yamuna River:
- The river contains a range of heavy metals, including chromium, cadmium, nickel, and zinc, even before it reaches Delhi.
- Industrial Areas:
- Mining operations in areas like Raniganj in West Bengal, Jharia in Bihar, and Singrauli in Madhya Pradesh release chromium, cadmium, lead, and mercury, which contaminate the soil and water.
- Thermal Power Plants:
- These plants, such as the Talcher thermal power plant in Orissa, release significant amounts of heavy metals like lead, zinc, cadmium, and uranium into the environment.
- Soil:
- Agricultural lands in many industrial areas have been rendered useless due to heavy metal contamination from industrial and agricultural activities.
- Bengaluru: