Concentration level and distribution of polycyclic aromatic hydrocarbons in soil and grass around Mt. Qomolangma, China

Abstract

High mountains may serve as a condenser for persistent organic pollutants. In the present study, soil and grass samples from Mt. Qomolangma region, China were collected from 4600 to 5620 m a.s.l and were analyzed for polycyclic aromatic hydrocarbons (PAHs) to determine if they are concentrated at colder, more elevated sites and to evaluate their possible resources and fractionation. The total PAHs concentration in soil samples was < 600 ng g −1 , the critical value to differentiate PAHs levels in remote and urban regions. This implied the PAHs levels at Mt. Qomolangma are relatively low and what one might expect in such a remote region of the world. These low values may represent a soil background for mid-latitude Northern Hemisphere soils away from the direct influence of an anthropogenic source. As for the distribution pattern, the low molecular weight PAHs were prone to accumulate at higher altitude, while the high molecular weight PAHs inversely related or unrelated with elevation. Based on high concentration of phenanthrene at elevated sample site and the ratios of individual PAHs, we deduced that home-heating combustion and vehicle emission may result in the constitution trait of PAHs in this mountain region. Monsoon traveling over India, Pakistan and other countries with dense population may carry contaminant to Mt. Qomolangma region.

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

“…The mean concentrations of Acy and Phe in soils from the NSHC were 31 and 28 ng/g, dw, which accounted for 25% and 23% of the mean concentration of total PAHs, respectively (Table 1). This result is consistent with results reported by Wang et al (2007). However, 27% of the soil samples from the NSHC had concentrations of Phe that were significantly greater than the maximum permissible concentration of 50 ng/g, dw, suggested by the Netherlands.…”

“…Based on above observations, it is easy to conclude that the significant and positive relationships between S 16 PAH concentrations and altitude occurred in our study because concentrations of LMW-PAHs contributed more than 70% to those of S 16 PAHs in both China and Nepal (Table 1). This result was also supported by Wang et al (2007) who suggested that concentrations of total and 3-ring PAHs in Himalayan soils were positively correlated with altitude (4700e5600 m), whereas no correlation was found for HMW-PAHs.…”

“…The main source of PAHs in the mountains is deposition from the atmosphere (Wang et al, 2007). Soil plays an important role in the global fate and distribution of PAHs.…”

Polycyclic aromatic hydrocarbons in Chinese surface soil: occurrence and distribution

“…PAHs were even detected in surface soil in high-mountain regions (e.g., Mt. Qomolangma,8,844.3 m a.s.l) and vast remote areas (e.g., the Qinghai-Tibetan Plateau), which indicated the national wide pollution of PAHs in China (Tao et al 2011;Wang et al 2007). In addition to local and national influence across China, PAH pollution can also influence the neighbor countries and regions through long-range atmospheric transport (Inomata et al 2012;Lang et al 2008;Primbs et al 2008).…”

Biosorption and biodegradation of polycyclic aromatic hydrocarbons by Phanerochaete chrysosporium in aqueous solution

“…POPs are widely distributed in the environment [1, 4,5], which are harmful to human health by breathing, drinking and food chain [6]. Therefore, the interfacial behavior, environmental transport, health effects, pollution control and restoration of POPs are widely concerned [610].…”