Environmental Pollution
From the particulate matter in our air to the 'dead zones' in our oceans, master the scientific indicators and metrics that define our environmental health.
Air Pollution: The AQI Framework
The Air Quality Index (AQI) is a tool designed to communicate the complex data of air pollutants into a single number and color code for public awareness.
The 8 Monitored Pollutants
PM10PM2.5NO2SO2COO3NH3Pb
PM2.5 Danger
Particulate Matter (PM2.5) is particularly dangerous because its small size (less than 2.5 microns) allows it to bypass the lung's defenses and enter the bloodstream directly.
Water Pollution: BOD and Eutrophication
Water quality is often measured by the amount of oxygen required to sustain aquatic life and decompose organic waste.
- Biochemical Oxygen Demand (BOD): The amount of dissolved oxygen required by aerobic organisms to break down organic matter.Note: High BOD = High Pollution Level.
- Eutrophication: The process where a water body becomes overly enriched with nutrients (Nitrogen/Phosphorus), leading to excessive algal growth and eventual 'hypoxia' (oxygen depletion).
The Eutrophication Cycle
Nutrient Runoff → Algal Bloom → Light Blockage → Algal Death & Decomposition → Oxygen Depletion → Fish Kill.
Waste Management
Solid waste management in India is governed by the Solid Waste Management Rules (2016), which emphasize source segregation and the 'extended producer responsibility' (EPR) for plastic and e-waste.