Application of multiple-path particle dosimetry model for quantifying age specified deposition of particulate matter in human airway

• Published in: Ecotoxicology and environmental safety Vol. 168; pp. 241 - 248
• Main Authors: Manojkumar, N., Srimuruganandam, B., Shiva Nagendra, S.M.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 30.01.2019
• Subjects: Adolescent; Air Pollutants - analysis; Child; Child, Preschool; Cities; Environmental Monitoring; Health risk assessments; Humans; India; Infant; Inhalation Exposure - analysis; Lobar deposition; Lung - drug effects; MPPD Model; Particle Size; Particulate Matter - analysis; PM Clearance; Regional deposition; Respiration; Seasons; Size-segregated PM; Young Adult; Cities; India; Size-segregated PM; Lobar deposition; Health risk assessments; PM Clearance; MPPD Model; Regional deposition
• ISSN: 0147-6513; 1090-2414
• DOI: 10.1016/j.ecoenv.2018.10.091

Particulate matter (PM) is crucial among six criteria air pollutants, and it is frequently associated with human morbidity and mortality. According to the aerodynamic diameter, PM is classified as coarse (PM10) and fine (PM2.5). PM with these smaller sizes can easily enter and get deposited in the human airways. This deposited PM fraction commences the development of respiratory diseases such as asthma, chronic obstructive pulmonary disease, and even cancer. Thus, the quantification of PM deposition and its clearance in the human airway are essential for evaluating health risks. This study aims to investigate the size-segregated PM (PM10, PM2.5, and PM1) deposition in human lungs. Size-segregated PM is collected using the Grimm portable environmental dust monitor during winter season near an arterial road located in Chennai city of Tamil Nadu state, India. Multiple-Path Particle Dosimetry (MPPD) Model version 3.04 is utilized for quantifying PM deposition. In MPPD, airway structures of infants (3 and 28 months), children (3, 8, 9 and 14 years) and adults (18 and 21 years) are considered for the study. The values of PM concentration, body orientation, breathing scenario, tidal volume, pause fraction, inspiration fraction, and breathing frequency are specified in the MPPD for quantifying PM depositions. Results showed that 8-year children and 28 months infant groups are recorded with maximum and minimum size-segregated PM deposition respectively. The coarse particles (PM10) are primarily deposited in the head (55–95%) and tracheobronchial (3–44%) regions whereas fine particles (PM2.5 and PM1) depositions are observed maximum in the head (36–63%) and pulmonary (28.2–52.7%) regions. Except for the adult age group, PM2.5 has the maximum deposition percentage in tracheobronchial and pulmonary regions. In the case of lobar depositions, lower lobes receive maximum deposition (66.4%) than the upper (27.2%) and middle lobes (6.4%). PM2.5 dominated the deposition in all five lobes of infant, children, and adults. The clearance rate of deposited PM is high in the tracheobronchial region whereas it is low in the pulmonary region. This study also concludes that PM2.5 is the important size fraction in lung deposition. Further, the study results can be used for human health risk assessments such as oxidative potential and toxicity of deposited PM. •Total, regional and lobar depositions of PM in eight human airways are quantified.•Maximum PM deposition is observed in children airways (8 and 9 years old).•PM10 highly deposited in Head and TB regions.•PM2.5 and PM1 have the maximum deposition in the alveolar region.•PM2.5 mass deposition in first 16 generations increases with age.