Q7. विश्व स्वास्थ्य संगठन (डब्ल्यू.एच.ओ.) द्वारा हाल ही में जारी किए गए संशोधित वैश्विक वायु गुणवत्ता दिशानिर्देशों (ए.क्यू.जी.) के मुख्य बिन्दुओं का वर्णन कीजिए । विगत 2005 के अद्यतन से, ये किस प्रकार भिन्न हैं ? इन संशोधित मानकों को प्राप्त करने के लिए, भारत के राष्ट्रीय स्वच्छ वायु कार्यक्रम में किन परिवर्तनों की आवश्यकता है ? (150 शब्दों में उत्तर दीजिए)
Q7. Describe the key points of the revised Global Air Quality Guidelines (AQGs) recently released by the World Health Organisation (WHO). How are these different from its last update? In What changes in India’s National Clean Air Programme are required to achieve these revised standards ? (Answer in 150 words) 10
The WHO`s new updated Global Air Quality Guidelines (AQGs):
- provide recommendations on air quality guideline levels as well as interim targets for six key air pollutants.
- They also offer qualitative statements on good practices for the management of certain types of particulate matter (PM), for example, black carbon/elemental carbon, ultrafine particles, and particles originating from sand and dust storms, for which there is insufficient quantitative evidence to derive AQG levels.
- the guidelines identify the levels of air quality necessary to protect public health worldwide.
- The AQGs also serve as a reference for assessing if, and by how much, the exposure of a population exceeds levels at which it might cause health concerns. They cover some of the most monitored pollutants critical for health, for which evidence on health effects from exposure has advanced the most in the past 15 years.
- The guidelines focus on classical pollutants, particulate matter (PM₂.₅ and PM₁₀), ozone (O₃), nitrogen dioxide (NO₂), sulfur dioxide (SO₂) and carbon monoxide (CO).
Difference between 2005 and 2021 AQG levels:
- Since the last 2005 global update, there has been a marked increase in the quality and quantity of evidence that shows how air pollution affects different aspects of health. For this reason, and after a systematic review of the accumulated evidence, several of the updated AQG values are now lower than 15 years ago.
Recommended 2021 AQG levels compared to 2005 air quality guidelines.
Compared to previous WHO guidelines, the new AQGs:
- use new methods for evidence synthesis and guideline development;
- reinforce evidence on health effects;
- provide higher certainty in the evidence of health effects occurring at lower levels than previously understood;
- offer additional AQG levels, such as for peak season O₃ and 24-hour NO₂ and CO, as well as some new interim targets;
- offer new good practice statements on the management of certain types of PM (i.e. black carbon/elemental carbon, ultrafine particles, and particles originating from sand and dust storms).
However, as the WHO’s guidelines are not binding, the move doesn’t immediately impact India as the National Ambient Air Quality Standards (NAAQS) don’t meet the WHO’s existing standards. The government has a dedicated National Clean Air Programme that aims for a 20% to 30% reduction in particulate matter concentrations by 2024 in 122 cities, keeping 2017 as the base year for the comparison of concentration.