Editorial

A significant drop in air pollution levels across India after about a month COVID-19 lockdown

The levels of NO 2 and ozone across India are within the National Ambient Air Quality Standards.

No clear relationship observed between current air quality vs confirmed COVID-19 cases in India.

During COVID-19 pandemic and lockdown enforced, countries across the world have reported a significant drop in air pollution and witnessed improvement in air quality.

In India, the most significant improvement in air quality during lockdown was observed in cities across Indo-Gangetic plain as in most of the normal days, particularly in winter months, particulate matter (PM10 and PM2.5 levels) and NO 2 values are high in Indo-Gangetic plain due to geographical location and other factors, including very high population density and spread of industrial clusters.

As per an earlier analysis done by Team of HCFI, after 11 days of COVID-19 lockdown, the level of particulate pollution (particulate matter, PM10 and PM2.5) dropped by nearly 60% in Delhi. PM10 (particulate matter 10 micrometres or less in diameter) and PM2.5 (particulate matter 2.5 micrometres or less in diameter) are particles present in the air that are classified as pollutants and can harm human health. The deadliest particle in Delhis foul air is PM 2.5 (primarily comes from combustion - fires, automobiles and power plants), which increases the likelihood of respiratory and cardiovascular diseases.

Across the globe, studies have been conducted to get a clear relationship between air pollution exposure and COVID-19 confirmed cases as high levels of air pollution can cause damage to the lungs and thus makes one more susceptible to either getting the infection or to getting complications from COVID-19. The World Economic Forum also said that people living with poor air quality may be more susceptible to COVID-19 disease.

A recent study w.r.t. exposure to air pollution and COVID-19 mortality in the United States by Xiao Wu et.al of Dept. of Biostatistics, Harvard T.H. Chan School of Public Health, USA, indicates that coronavirus patients in areas with high levels of air pollution before the pandemic, have increased odds of dying from the infection than patients in cleaner parts of the country. This study offers the first clear association between long-term exposure to pollution and COVID-19 death rates.

The authors in above study found that an increase of only 1 μg/m3 in PM2.5 is associated with a 15% increase in the COVID-19 death rate. Results are statistically significant and robust to secondary and sensitivity analyses. They have concluded that a small increase in long-term exposure to PM2.5 leads to a large increase in COVID-19 death rate. The study results highlight the importance of continuous enforcement of existing air pollution regulations to protect human health both during and after the COVID-19 crisis.

In this regard, Team of Experts of HCFI has done detailed analysis of air quality data ( Air Quality Index- AQI, PM10, PM2.5, NO 2 and Ozone) from about 180 Continuous Ambient Air Quality Monitoring Stations (CAAQMS) across India and correlated with confirmed COVID-19 cases . Status of confirmed COVID-19 cases of various States/UTs as on 21-04-2020 and corresponding State/UT wise Air Quality status ( as per average CPCB/SPCB data w.r.t. National Air Quality Index as on 21-04-2020 at 4:00 PM) is given below in the Table:

State/UT Confirmed COVID-19 Cases AIR Quality status ( PM10, PM2.5, NO2 and Ozone values in microgram per meter cube) Andhra Pradesh 722 AQI range City CAAQMS Location AQI PM10 PM2.5 NO2 Ozone 38-52 Amrawati Secretariat 52 52 18 30 13 Raja Mahendravaram Aanad Kala kshetram 38 16 9 5 38 Tirupati Tirumala 39 13 10 8 39 Visakha-patnam GVM 52 52 18 30 13 Corporation Bihar 113 49-139 Gaya Collectorate 96 - 48 21 96 Muzaffarpur Collectorate 61 - 34 30 61 Patna Govt. High School 108 108 26 11 4 Muradpur 64 64 40 17 9 Rajbansi 49 49 30 - 21 Nagar Samanpura 139 49 47 30 53 Chandigarh 26 30 Chandigarh Sector-25 30 30 22 15 29 Delhi 2081 55-163 Delhi Alipur 94 94 54 26 67 Anand Vihar 84 84 77 21 56 Aya Nagar 62 62 56 18 26 Bawana 118 118 100 22 89 CRRI 77 77 56 18 14 DTU 97 86 61 22 97 Dwarka 89 84 50 20 89 Sector-8 IGI Airport 64 64 45 - 34 IHBAS 68 - 20 - - JLN stadium 89 70 43 18 89 Lodi Road 64 64 - - 64 National stadium 66 66 59 19 31 Mandir Marg 72 72 51 34 20 Nehru Nagar 163 79 68 22 163 Okhla phase-2 89 - 42 19 6 Patparganj 55 55 41 12 35 Punjabi Bagh 77 77 65 34 31 R.K. Puram 63 63 43 25 46 Rohini 98 98 89 11 19 Shadipur 81 - 26 27 81 Sirifort 64 64 45 19 60 Sri Auro-bind Marg 121 48 37 6 121 Vivek Vihar 87 87 62 30 52 Wazirpur 75 75 67 33 45

State/ UT Confirmed COVID-19 cases AIR Quality status ( PM10, PM2.5, NO2 and Ozone values in microgram per meter cube) Gujrat 1939 AQI range City CAAQMS Location AQI PM10 PM2.5 NO2 Ozone 51-75 Ahmedabad Maninagar 72 72 47 17 60 Ankleshwar GIDC 75 75 51 6 47 Gandhi Nagar Sector-10 56 56 34 4 31 Nandesari GIDC 51 49 28 51 - Vatva Phase-4 GIDC 69 69 53 31 24 Haryana 254 25-165 Ambala Patti Mehar 42 - 39 21 42 Bahadurgarh Arya Nagar 77 77 74 23 58 Ballabhgarh Nathu Colony 74 64 74 11 14 Bhiwani H.B. Colony 62 58 24 18 62 Daruhera Municipal corporation office 63 50 61 13 63 Faridabad Sector-30 98 98 19 14 41 Sector-16 A 165 - 48 - 165 Fatehabad Huda sector 64 59 45 10 64 Gurugram NISE Gwal Pahari 67 67 50 12 35 Sector-51 118 85 58 19 118 TERI gram 85 59 56 - 85 Vikas Sadan 121 - 51 27 121 Hisar Urban Estate-II 70 70 46 24 28 Jind Police line 64 51 50 19 64 Kaithal Rishi Nagar 50 50 35 29 22 Karnal Sector-12 54 - 54 10 34 Kurukshetra Sector-7 56 40 33 14 56 Mandikhera General Hospital 64 64 33 - 40 Manesar Sector-2 IMT 73 73 25 2 - Narnaul Shastri Nagar 53 53 34 - 14 Palwal Shyam Nagar 115 115 94 8 14 Panchkula Sector-6 25 - 25 22 24 Panipat Sector-18 91 91 41 70 46 Rohtak M D Univ. 49 - 49 - 27 Sirsa F Block 69 69 37 6 24 Sonepat Murthal 83 83 32 35 15 Yamunanagar Govindpura 81 58 44 20 81 Karnataka 408 31-60 Bengaluru BTM layout 50 32 - 17 36 Bapuji nagar 51 31 18 9 51 Hebbal 31 31 18 3 - Jaya Nagar 34 29 24 26 34

State/ UT Confirmed COVID-19 cases AIR Quality status ( PM10, PM2.5, NO2 and Ozone values in microgram per meter cube) Karnataka (continued) 408 AQI range City CAAQMS Location AQI PM10 PM2.5 NO2 Ozone 31-60 Bengaluru Peenya 60 - 60 8 - Sanegurva Hill 38 38 - 24 - Silk board 35 32 23 6 35 Bagalkot Vidayagiri 53 38 - 5 53 Chikkballapur Chikkaballapur rural 45 33 18 16 45 Chickamangaluru Kalyana nagar 52 52 35 25 28 Mysuru Hebbal Ist stage 52 35 24 13 52 Rama nagara Vijay nagar 39 39 30 15 9 Kerala 408 33-60 Ernakulam Kacherypady 60 23 16 - - Kannur Thavakkara 59 53 59 18 14 Kochi Vyttila 52 27 28 6 2 Kolam Polayathode 47 37 47 13 5 Kozhikode Palayam 42 41 42 10 9 Thiruvanthapuram Kanavattorm 55 39 37 14 55 Plammoodu 33 27 12 8 28 Madhya Pradesh 1485 45-169 Bhopal T.T. Nagar 109 109 68 12 104 Damoh Shrivastav colony 45 - 45 19 - Dewas Bhopal chauraha 110 101 110 22 74 Gwalior City Centre 95 44 24 11 95 Phool bagh 72 - 72 - - Indore Chhoti Gwaltoli 100 100 78 61 37 Jabalpur Marhatal 104 104 55 27 64 Katni Gole Bazar 123 123 62 20 94 Maihar Sahilara 64 64 30 43 - Mandideep Sector- D Ind. Area 59 59 58 16 25 Pithampur Sector-2 Ind. Area 116 116 78 14 16 Singrauli Vindhyachal 169 151 99 33 169 Ujjain Mahakaleshwar 159 114 159 16 150 Mizoram 1 24 Aizawl Sikulpuikawn 24 24 - 1 12 Jharkhand 46 93 Jorapokhar Tata stadium 93 93 39 14 - Assam 35 35 Guwahati Railway colony 35 35 33 8 32 Odisha 74 99 Brajraj Nagar GM office 99 99 95 - -

State/ UT Confirmed COVID-19 cases AIR Quality status ( PM10, PM2.5, NO2 and Ozone values in microgram per meter cube) Maharasthra 4666 AQI range City CAAQMS Location AQI PM10 PM2.5 NO2 Ozone 44-89 Aurangabad More chowk Waluj 52 38 33 17 52 Chandrapur Chandrapur 65 65 49 16 24 Khutala 85 34 36 19 85 Mumbai Bandra 55 55 27 5 - Chhatrapati Shivaji Int. Airport 60 60 - 7 - Colaba 44 - 26 3 44 Kurla 76 76 - 20 18 Powai 78 62 29 3 26 Sion 89 89 50 18 34 Worli 52 52 30 5 28 Nasik Gangapur road 56 41 39 26 56 Navi Mumbai Mahape 87 87 42 30 42 Nerul 70 69 44 13 28 Pune Karve road 50 35 37 11 20 Solapur solapur 44 44 42 - 36 Punjab 245 30-96 Amritsar Golden temple 43 40 17 17 43 Bathinda Hardev nagar 96 32 11 23 - Jalandhar Civil line 36 36 35 11 18 Khanna Kalal majra 33 33 25 8 20 Ludhiana Punjab Agri. Univ. 35 25 22 20 35 Mandi Govindgarh RIMT univ 96 32 11 23 96 Patiala Model town 37 37 24 8 17 Rup nagar Ratanpura 30 30 24 16 - Rajasthan 1576 57-82 Alwar Moti Doongri 66 39 35 43 66 Ajmer Civil line 77 51 31 11 77 Bhiwadi RIICO Ind. Area-III 74 74 55 15 55 Jaipur Adarsh nagar 82 30 22 15 82 Police Commissionerate 68 58 43 22 68 Shatri nagar 70 28 22 19 70 Jodhpur Collectorate 79 79 52 27 53 Kota Shrinathpuram 57 38 34 17 57 Pali Indra colony vistar 76 76 51 15 75 Udaipur Ashok nagar 81 55 44 15 81

State/ UT Confirmed COVID-19 cases AIR Quality status ( PM10, PM2.5, NO2 and Ozone values in microgram per meter cube) Tamilnadu 1520 AQI range City CAAQMS Location AQI PM10 PM2.5 NO2 Ozone 26-68 Chennai Alandur bus depot 26 - 16 2 26 Manali village 68 - 16 8 68 Manali 40 - 37 9 - Velachri res area 40 - 5 2 30 Telangana 873 41-60 Hyderabad Bollaram Ind. area 53 53 42 39 28 Central Univ. 45 35 22 45 5 ICRISAT 41 41 30 22 20 IDA Pasahamylaram 50 46 35 50 24 Sanathnagar 49 - 48 12 49 Zoo park 60 - 60 54 19 Uttar Pradesh 1184 55-161 Agra Sanjay palace 114 - 114 64 11 Bulandshahar Yamunapuram 161 161 137 29 117 Ghaziabad Indirapuram 89 89 57 25 82 Loni 123 123 90 16 82 Sanjay nagar 109 109 95 44 60 Vasundhara 89 89 67 51 22 Greater Noida Knowledge park III 113 113 82 - 92 Knowledge Park V 102 102 - 26 90 Hapur Anand vihar 159 159 83 74 2 Kanpur Nehru nagar 62 - 50 13 62 Lucknow Central School 114 - 114 9 11 Gomti nagar 74 - 74 24 59 Lal bagh 55 - 43 22 18 Talkatora distric centre 67 - 67 9 - Meerut Ganga nagar 92 92 48 24 28 Pallavpuram phase II 113 113 60 16 18 Mujaffar nagar New mandi 103 103 67 7 19 Noida Sector 62 89 72 89 17 65 Sector 1 104 104 55 19 83 Sector116 77 - 77 23 46

State/ UT Confirmed COVID-19 cases AIR Quality status ( PM10, PM2.5, NO2 and Ozone values in microgram per meter cube) West Bengal 392 AQI range City CAAQMS Location AQI PM10 PM2.5 NO2 Ozone 21-69 Howrah Belur Math 21 21 14 20 - Ghusuri 58 42 27 18 56 Padmapukar 28 27 28 13 13 Kolkata Bollygunge 52 27 13 6 52 Bidhan nagar 48 25 20 7 48 Fort Villiam 55 26 23 14 55 Jadavpur 27 27 16 11 20 Ravindra Bharti Univ. 69 25 20 25 69 Rabindra sarobar 48 21 - 8 48 Victoria 41 31 18 16 41 Siliguri Ward 32 Bapupura 38 32 38 38 22

The above data of current Air Quality vs. confirmed COVID-19 cases in India do not show any clear relationship. However, long-term exposure of higher levels of air pollutants, particularly higher PM2.5 levels, may weaken the immunity and thus raise the risk of COVID-19 infection. Detailed study in this regard is needed.

However, as per present study, the levels of NO 2 and Ozone throughout India are found within the National Ambient Air Quality Standards, notified as per the Central Pollution Control Board Notification in the Gazette of India, dated 18th November, 2009 (PM10 std. 24 hourly = 100 microgram per meter cube, PM2.5 std. 24 hourly = 60 microgram per meter cube, NO 2 std. 24 hourly = 80 microgram per meter cube and Ozone std. 1 hourly = 180 microgram per meter cube).

Levels of PM10 and PM2.5 have significantly declined during lockdown period as compared to normal days. However, levels of PM10 and PM2.5 in some States/UTs at few locations are found above the standards.

Though, presently, we have observed clean air due to the lockdown in India but this respite is for a short-term period. After the restrictions are lifted and human activities start, there will be a sudden rise in air pollution. But, the lockdown during COVID-19 has shown ways to tackle air pollution issues, only what’s needed is political will, societal interventions and strict enforcement.

Dr KK Aggarwal

President CMAAO, HCFI and Past National President IMA