Study of Toxicity of Air Pollution

Study of Toxicity of Air Pollution: Recently, a pioneering long-term study by researchers at Kolkata’s Bose Institute revealed that simply measuring the concentration of air pollutants like PM2.5 is insufficient.

o The study emphasizes that the toxicity, or the potential harm these pollutants cause to the human body, must also be factored into air quality assessments.

• Key Highlights: The study found that in Kolkata, the toxicity of PM2.5 pollutants increases sharply once concentrations exceed 70 µg/m³, continuing up to around 130 µg/m³, after which the damage potential levels off.

  o This is the first study in India to examine how the oxidative toxicity of PM2.5 varies with its concentration.

  o The human body responds to air pollutants by producing Reactive Oxygen Species (ROS), which, in excess, can harm healthy cells.

  o Antioxidants counter ROS, but their limited supply means high pollutant levels can overwhelm the body, causing oxidative stress and cell damage.

  o Pollution below 70 µg/m³ affects health, but toxicity—and health risk—increases sharply beyond this threshold.

  o Toxicity is influenced more by the chemical composition of pollutants, especially from biomass and solid waste burning, than by particle volume.

  o Vehicular emissions also contribute to toxicity but are less harmful than emissions from waste combustion.

  o Different cities have varied pollution sources, so toxicity thresholds are likely to differ by location.

  o The study recommends city-specific, toxicity-based air quality warning systems tailored to local pollution sources.