NEW DELHI: A joint study by Physical Research Laboratory, Ahmedabad, and Delhi Technological University has examined the presence and impact of airborne nanoparticles (PM1 or smaller) on pedestrians’ respiratory systems in Delhi.
The findings indicate a significant accumulation of these particles in the deeper sections of the lungs. The study found that Delhi residents encounter approximately 10-18 million nanoparticles daily while walking along the road. It added that nanoparticle deposits near roads exceed those in areas distant from traffic by 30%. These minute particles pose a greater health risk compared to PM2.5 or PM10 due to their significantly smaller dimension.
The report stated that the ultrafine particles contribute around 60-80% of the total particle number concentration over Delhi. “Inhalation particle number concentration varies between 0.5 and 1 billion over Delhi during the year…. The particle deposition ranges from 0.43-0.26g/min over Delhi during the year. The concentration of particles in the urban roadside is nearly 30% higher than an environment away from the road. The results are crucial for initiating mitigation measures aimed to improve air quality and public health,” the report said.
The study, titled Seasonal Variation of Particle Number Concentration in a Busy Urban Street with Exposure Assessment and Deposition in Human Respiratory Tract, was published by Elsevier. It was conducted by a team of researchers that included Rajeev Kumar Mishra, associate professor from the department of environmental engineering at Delhi Technological University, along with senior professor S. Ramachandran from the Physical Research Laboratory, Ahmedabad, and Kanagaraj Rajagopal, research scholar from the advance air and acoustics research laboratory of Delhi Technological University.
The research was conducted in Rohini district, north Delhi. It analysed the impact of atmospheric nanoparticles on the human respiratory system, covering all seasons.
“Using a computerised model for analysing the deposition, the study revealed that more nanoparticles are deposited in the alveolar regions of the human lungs. Because these nanoparticles are about 500 times smaller than the size of human hair, they penetrate deep into the lungs” and “have the potential to penetrate our bloodstream” and can be deposited in different parts of the body, “including the brain”, the report pointed out.
It added that the nanoparticles were found high near the sources, such as roadsides, where most of the population is exposed to these particles. “So, for a city like Delhi, residential zones adjacent to the road will automatically have higher exposure for the residents. The people working or living near the road, such as police personnel, street vendors, drivers, motorcyclists, delivery personnel and the urban poor living near the road, are suspected to be more vulnerable to the nanoparticles. The study also suggests that the policy formulation towards the concentrations of these particles is required for reducing the nanoparticle emissions from the engine sources to mitigate the impacts of these particles on the atmosphere and human health,” Rajeev Kumar Mishra, one of the authors of the report, said.
The findings indicate a significant accumulation of these particles in the deeper sections of the lungs. The study found that Delhi residents encounter approximately 10-18 million nanoparticles daily while walking along the road. It added that nanoparticle deposits near roads exceed those in areas distant from traffic by 30%. These minute particles pose a greater health risk compared to PM2.5 or PM10 due to their significantly smaller dimension.
The report stated that the ultrafine particles contribute around 60-80% of the total particle number concentration over Delhi. “Inhalation particle number concentration varies between 0.5 and 1 billion over Delhi during the year…. The particle deposition ranges from 0.43-0.26g/min over Delhi during the year. The concentration of particles in the urban roadside is nearly 30% higher than an environment away from the road. The results are crucial for initiating mitigation measures aimed to improve air quality and public health,” the report said.
The study, titled Seasonal Variation of Particle Number Concentration in a Busy Urban Street with Exposure Assessment and Deposition in Human Respiratory Tract, was published by Elsevier. It was conducted by a team of researchers that included Rajeev Kumar Mishra, associate professor from the department of environmental engineering at Delhi Technological University, along with senior professor S. Ramachandran from the Physical Research Laboratory, Ahmedabad, and Kanagaraj Rajagopal, research scholar from the advance air and acoustics research laboratory of Delhi Technological University.
The research was conducted in Rohini district, north Delhi. It analysed the impact of atmospheric nanoparticles on the human respiratory system, covering all seasons.
“Using a computerised model for analysing the deposition, the study revealed that more nanoparticles are deposited in the alveolar regions of the human lungs. Because these nanoparticles are about 500 times smaller than the size of human hair, they penetrate deep into the lungs” and “have the potential to penetrate our bloodstream” and can be deposited in different parts of the body, “including the brain”, the report pointed out.
It added that the nanoparticles were found high near the sources, such as roadsides, where most of the population is exposed to these particles. “So, for a city like Delhi, residential zones adjacent to the road will automatically have higher exposure for the residents. The people working or living near the road, such as police personnel, street vendors, drivers, motorcyclists, delivery personnel and the urban poor living near the road, are suspected to be more vulnerable to the nanoparticles. The study also suggests that the policy formulation towards the concentrations of these particles is required for reducing the nanoparticle emissions from the engine sources to mitigate the impacts of these particles on the atmosphere and human health,” Rajeev Kumar Mishra, one of the authors of the report, said.
