Temporal distribution of fine particulates (PM_2.5,PM₁₀), potentially toxic metals, PAHs and Metal-bound carcinogenic risk in the population of Lucknow City, India

Abstract

Ubiquitous fine particulates can readily be bound to toxic metals and polycyclic aromatic hydrocarbons and are considered to be a great threat to human health. The purpose of this study was to assess the magnitude of air pollution risks to public health by determining four crucial parameters- inhalable particulates, metals in particulates and PAHs which are associated with PM₁₀ in the air environment of Lucknow, India during 2007-09. The values of PM₁₀ and PM₂.₅ ranged between 102.3-240.5 and 28.0-196.9 μg/m³ whilst the average PM₁₀ was 1.7 times and PM was 1.5 times higher than their respective NAAQS of 100 and 60 μg/m³ respectively. The estimated relative death rate and hospital admissions for each increase in the PM₁₀ levels of 10 μg/m³ ranged from 1.5-8% and from 3.9-8.0% (as per APHEA2 1990) respectively in persons > 65 yrs. Among the locations; AQ, AQ and AQ (with diversified activities and heavy traffic) recorded higher concentrations of both the particulate fractions than the AQ (residential area with low traffic). The average concentrations of Fe, Pb, Ni, Cu, Cr, Cd in PM₁₀ were 219.4, 40.6, 35.1, 27.3, 22.2 and 16.2 ng/m³ and that in PM₂.₅ were 54.3, 33.9, 38.5, 29.4, 8.4, and 1.17 ng/m³ respectively Regression analysis revealed that correlation of metals with PM₂.₅ was stronger than PM. The ratio of metals adsorbed on surface of particles (PM₂.₅:PM₁₀) reveals that PM₂.₅ has more affinity for Ni, Cu and Pb and PM₁₀ for Cd, Fe and Cr. Health risk due to carcinogenic metals bound to respirable particulates was predicted by estimating excess cancer risk (ECR). The highest ECR value was estimated for Cr, 266.70 × 10⁻⁶, which was associated with PM10 and 100.92 × 10⁻⁶ which was associated with PM₂.₅, whereas lead has the lowest ECR value. Amongst PAHs, benzo(a)pyrene (51.96 ± 19.71 ng/m) was maximum in PM₁₀ samples. Maximum concentrations of PM₁₀, PM₂.₅, metals and PAHs were detected during winter, and the lowest was during monsoon. The higher prevalence of diseases among the population may be due to high concentration of particulates coated with toxic metals and PAHs present in air environment.

Assessment of Seasonal Variations of Average Traffic Pollution Levels in Curbside Open-Air Microenvironments in Kolkata, India

“…An EF of > 1 indicates that the PM 2.5 concentration was also higher than the standard prescribed by the CPCB in both seasons. Concentrations of PM 2.5 higher than the prescribed standard in Indian cities has also been reported by a number of researchers (28)(29)(30). The average EF for NO 2 concentration (EF-NO 2 ) was 1.50 ± 0.43 post-monsoon and 0.95 ± 0.0.29 pre-monsoon.…”

Atmospheric Fine and Coarse Mode Aerosols at Different Environments of India and the Bay of Bengal During Winter-2014: Implications of a Coordinated Campaign

“…In another study, PM 2.5 mass concentration during winter over Delhi was observed to be 151.2 ± 26.1 lg m -3 [29]. Barman et al [30] carried out a study to discern the mass concentrations of fine particulates in two residential areas of [31]. Annual average PM 2.5 mass concentrations for Agra was estimated to be 104.9 ± 47.1 lg m -3 and 91.1 ± 50.3 lg m -3 at urban and rural sites respectively [18].…”

Size distribution of total and water-soluble fractions of particle-bound elements—assessment of possible risks via inhalation

“…10 Relative contribution of particle-bound elements to carcinogenic risk in urban-traffic (UT) and urban-background site (UB) based on: (a) total concentrations and, (b) water-soluble concentrations (As, Cd, Co, Cr, Ni) in Nanjing, China was 2×10 −5 for children and 8×10 −5 for adults, with Cr posing the higher risk. Pandey et al (2013) reported that Cr in both PM 10 and PM 2.5 fractions in Lucknow city, India, exhibited the highest cancer risk (267×10 −6 and 101×10 −6 , respectively), followed by Cd, Ni, and Pb. Shi et al (2011) also reported that Cr was the dominant contributor to carcinogenic risk posed by exposure to urban road dust in Shanghai, with minor contribution from As and Cd.…”