Model Answer
0 min readIntroduction
Marine pollution, defined as the introduction of harmful substances or energy into the marine environment, poses a significant threat to India’s vast coastline and oceanic resources. India, with its 7,516.6 km coastline and extensive Exclusive Economic Zone (EEZ), is particularly vulnerable. Rapid industrialization, urbanization, agricultural runoff, and increasing maritime traffic contribute to escalating levels of pollution. Recent incidents like oil spills and plastic accumulation highlight the urgency of addressing this issue. Understanding the sources of pollution and employing sophisticated analytical techniques for monitoring are crucial for effective mitigation and conservation.
Marine Pollution in India
Marine pollution in India stems from a variety of sources, categorized as point and non-point sources.
- Point Sources: These are identifiable and localized sources.
- Industrial Effluents: Discharge from industries like textiles, pharmaceuticals, petrochemicals, and thermal power plants containing heavy metals, organic pollutants, and thermal pollution. For example, the discharge from refineries along the Gujarat coast.
- Sewage Discharge: Untreated or partially treated sewage from coastal cities contributes significantly to nutrient enrichment (eutrophication) and pathogen contamination. Cities like Mumbai, Kolkata, and Chennai are major contributors.
- Oil Spills: Accidental spills from tankers, offshore oil platforms, and port operations. The 2010 oil spill off the Mumbai coast due to a collision between two ships is a notable example.
- Agricultural Runoff: Fertilizers and pesticides used in agriculture are washed into rivers and eventually reach the sea, causing nutrient pollution and harming marine life.
- Non-Point Sources: These are diffuse and widespread sources.
- Plastic Pollution: A major concern, with India being a significant contributor to plastic waste entering the oceans.
- Atmospheric Deposition: Pollutants from the atmosphere, such as heavy metals and persistent organic pollutants, are deposited into the marine environment through rainfall and dry deposition.
- Mining Activities: Coastal mining activities release sediment and pollutants into the water.
Impacts of Marine Pollution: The consequences are far-reaching, including:
- Damage to Marine Ecosystems: Coral reef degradation, mangrove destruction, and loss of biodiversity.
- Threat to Human Health: Consumption of contaminated seafood can lead to health problems.
- Economic Losses: Impacts on fisheries, tourism, and shipping industries.
Analytical Techniques for Determining Toxic Elements in Water
Determining the presence and concentration of toxic elements in marine water requires sophisticated analytical techniques. These techniques can be broadly categorized into spectroscopic and electrochemical methods.
1. Spectroscopic Techniques
| Technique | Principle | Applications | Limitations |
|---|---|---|---|
| Atomic Absorption Spectrometry (AAS) | Measures the absorption of light by free atoms in the gaseous state. | Determination of heavy metals like lead, cadmium, mercury, and arsenic. | Requires sample pre-concentration for trace element analysis; limited to single element analysis. |
| Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) | Excites atoms in a plasma, causing them to emit light at characteristic wavelengths. | Multi-element analysis; suitable for a wide range of elements. | Matrix effects can interfere with accuracy. |
| Inductively Coupled Plasma Mass Spectrometry (ICP-MS) | Ionizes the sample in a plasma and measures the mass-to-charge ratio of the ions. | Highly sensitive; capable of detecting trace elements at very low concentrations. | Expensive instrumentation; requires skilled operators. |
2. Electrochemical Techniques
- Voltammetry: Measures the current as a function of applied potential. Used for determining the concentration of electroactive species like heavy metals.
- Ion Selective Electrodes (ISEs): Measure the potential difference across a membrane selective to a specific ion. Used for direct measurement of ion concentrations.
3. Other Techniques
- Gas Chromatography-Mass Spectrometry (GC-MS): Used for analyzing organic pollutants like pesticides and hydrocarbons.
- High-Performance Liquid Chromatography (HPLC): Used for separating and quantifying organic compounds.
Recent Advancements: The use of nanotechnology-based sensors for real-time monitoring of pollutants is gaining traction. Biosensors, utilizing biological components to detect specific pollutants, are also being developed.
Conclusion
Marine pollution in India is a complex issue demanding a multi-faceted approach. Effective monitoring using advanced analytical techniques like ICP-MS and GC-MS is crucial for identifying pollution sources and assessing their impact. Strengthening regulations, promoting sustainable industrial practices, improving sewage treatment infrastructure, and raising public awareness are essential steps towards mitigating marine pollution and preserving India’s valuable marine resources. Integrated coastal zone management plans, incorporating scientific monitoring and community participation, are vital for long-term sustainability.
Answer Length
This is a comprehensive model answer for learning purposes and may exceed the word limit. In the exam, always adhere to the prescribed word count.