Particle PM 2.5 - A Invisible Death Agent Of Nature

 Particulate matter PM2.5 (particles less than 2.5 micrometers in diameter) can penetrate deeply into the lung, irritate and corrode the alveolar wall, and consequently impair lung function. Smog is generally caused by high concentrations of fine particles (particle size less than or equal to 2.5 btm, referred to as PM2.5) or aerosols. 

PM2.5 has small diameters, however large surface areas and may therefore be capable of carrying various toxic stuff, passing through the filtration of nose hair, reaching the end of the respiratory tract with airflow and accumulating thereby diffusion, damaging other parts of the body through air exchange in the lungs.
It is reported that 76·8% of the population, were exposed to PM_2·5 greater than 40 μg/m³ in India which is limited by  National Ambient Air Quality Standards in India  of which Delhi had the highest mean PM_2·5 in 2017, followed by Uttar Pradesh, Bihar, and Haryana, all with mean values greater than 125 μg/m³  in north India(India State-Level Disease Burden Initiative Air Pollution Collaborators.,2017).

 PM 2.5 decreased the average life span by 8.6 months.

American Cancer Society, Pope, and coworkers collected a set of data, based on 500,000 adults living in large cities. They concluded that the overall mortality and mortality of cardiopulmonary diseases, as well as lung cancer, increased by 4%, 6% and 8%, respectively, for every 10 µg/m³ PM2.5 increase, after ruling out smoking, diet, drinking, occupation and other risk factors. In addition, a cohort study by the American Cancer Society tracked 1.2 million American adults for 26 years [1982–2008] and found that the mortality of lung cancer increased by 15–27% when PM2.5 air concentrations increased by 10 µg/m^3.

Data from the program (http://stateair.net/web/mission/1/) which tracks daily PM2.5 concentrations on the grounds of the U.S. Embassy in Beijing in the winter months from 2010 to 2014 showed that daily PM2.5 concentrations exceeded 100 µg/m³ for more than half of the days and reached as high as 744 µg/m³, more than 20 times the US Environmental Protection Agency’s (EPA) 24-hour standard for PM2.5 of 35 µg/m³. Surveys in Beijing, Shanghai, Guangzhou, and other areas in China displayed a strong linear correlation between daily mortality (including non-accidental death) and PM2.5 levels.

 In 1996, Donaldson and Beswick, etc. reported that the surface itself of environmental particles can produce free radicals. In addition, that the PM2.5 surface was rich in iron, copper, zinc, manganese, and other transition elements, as well as polycyclic aromatic hydrocarbons and lipopolysaccharide, etc. These components can increase free radical production in the lung, consume antioxidant ingredients and cause oxidative stress.
Hydroxyl radical (• OH) by activating metals. Hydroxyl radicals are the main factor causing oxidative damage to DNA. When damaged DNA is not effectively repaired in time, it can induce teratogenesis carcinogenesis, mutagenesis.

Particulate matter concentrations were significantly higher in both north and south Indian kitchens than in non-kitchen areas. The concentrations of TVOC, CO, and CO₂ were higher in the kitchens of north and south India than in the control locations (non-kitchen areas). Coarse, fine, and ultrafine particles and several elements were also detected in kitchens in both locations by SEM and elemental analysis. The FTIR spectra of kitchen indoor air at both locations show the presence of organic chemicals. Significant declines in systolic blood pressure and lung function were observed in the kitchen workers with MAU at both locations compared to those of the control subjects. A higher prevalence of obstruction cases with MAU was observed among the workers in the southern region than in the controls (p < 0.01).

References-   

• Manish Kapoor, Managing Ambient Air Quality Using Ornamental Plants-An Alternative Approach Department of Botany, Punjabi University, India  Universal Journal of Plant Science 5(1): 1-9, 2017 http://www.hrpub.org DOI: 10.13189/ujps.2017.050101
•    CECB.,2020 http://chtenvis.nic.in/Air%20Pollution.html.