Identification of sources of polycyclic aromatic hydrocarbons based on concentrations in soils from two sides of the Himalayas between China and Nepal

Abstract

a b s t r a c tTo understand distribution and sources of polycyclic aromatic hydrocarbons (PAHs) in the Himalayas, 77 soil samples were collected from the northern side of the Himalayas, China (NSHC), and the southern side of the Himalayas, Nepal (SSHN), based on altitude, land use and possible trans-boundary transport of PAHs driven by wind from Nepal to the Tibetan Plateau, China. Soils from the SSHN had mean PAH concentration greater than those from the NSHC. Greater concentrations of PAHs in soils were mainly distributed near main roads and agricultural and urban areas. PAHs with 2e3 rings were the most abundant PAHs in the soils from the Himalayas. Concentrations of volatile PAHs were significantly and positively correlated with altitude. Simulations of trajectories of air masses indicated that distributions of soil PAH concentrations were associated with the cyclic patterns of the monsoon. PAH emissions from traffic and combustion of biomass or coal greatly contributed to concentrations of PAHs in soils from the Himalayas.

Polycyclic aromatic hydrocarbons in soils from the Central-Himalaya region: Distribution, sources, and risks to humans and wildlife

“…Areas in the Himalayas at altitudes higher than 3.0 × 10 3 m are largely unpopulated (Loewen et al, 2005). The distribution of human population (Luo et al, 2016) partly explained the pattern of distributions of PAHs in soils (Fig. 2D).…”

“…Distributions of populations of humans play important role in determining the spatial distribution of PAHs. Population density is greater in Nepal than in the TP study area (Luo et al, 2016). Areas in the Himalayas at altitudes higher than 3.0 × 10 3 m are largely unpopulated (Loewen et al, 2005).…”

Persistent organic compounds in the environment their impact on human health: A review

“…Coal and burning of woods [22], incomplete combustion of oil gas, coal, biomass, garbage, tobacco, charbroiled meat, vehicular exhaust emission, oil exploration (refining), power generation and industrial production, and jet aircraft exhausts, roofing tar, sewage sludge and creosote materials are some sources because of anthropogenic activities [23][24][25][26].…”

Contaminación en agua y sedimentos por hidrocarburos aromáticos policíclicos: Revisión de la dinámica y los métodos analíticos

“…Los HAP se depositan en el agua y los sedimentos por medio de procesos de transferencia atmosférica dados por precipitación, cambios térmicos o asociados al material particulado de gran tamaño. Cuando estas sustancias alcanzan el suelo, algunos procesos de escorrentía los transportan hasta las fuentes de agua donde las propiedades fisicoquímicas de los HAPs y el medio, actúan en la transferencia agua-sedimento (Nikolaou et al, 2009;Luo et al, 2016).…”

“…En cuanto a los HAP analizados en sedimentos, se han hallado un gran número de origen petrogénico en las zonas de interés económico de Catar de la península Arábiga, debido a la presencia de empresas dedicadas a la extracción y refinación del petróleo, los 16 HAP estudiados estaban en el rango de 2,6 a 1025 ng g -1 (Soliman et al, 2014). De igual manera, concentraciones de estas sustancias han sido reportadas en sedimentos recolectados en las montañas del Himalaya entre Nepal y China (Luo et al, 2016), donde se determinaron valores entre 2,3 y 800 ng g -1 (Tabla 4), confirmando el transporte y deposición de material partículado nocivo en lugares apartados de las urbes.…”