Sources and characteristics of lead pollution in the urban environment of Guangzhou

• Published in: The Science of the total environment Vol. 385; no. 1; pp. 182 - 195
• Main Author: DUZGORENAYDIN, N
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier B.V 15.10.2007; Elsevier Science
• Subjects: Applied sciences; China; Cities; Environmental Monitoring; Environmental Pollutants - analysis; Environmental Pollution - analysis; Exact sciences and technology; Geologic Sediments - analysis; Global environmental pollution; Guangzhou; Isotopes; Lead - analysis; Pb contamination; Pb isotope composition; Pollution; Soil - analysis; Urban dusts; Urban geochemistry; Urbanization; Vehicle Emissions - analysis; Asia; China; China, People's Rep., Guangdong Prov., Guangzhou; China, People's Rep., Zhu R; Guangzhou; Urban dusts; Urban geochemistry; China; Pb contamination; Pb isotope composition; Isotopic analysis; Uncertainty; Lead isotopes; Identification; Urban area; Pollution; Investigation method; Pollution source inventory; Lead; Environment; Sampling; Anthropogenic factor
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2007.06.047

Guangzhou, the capital of the southeastern province of Guangdong, is one of the largest and most rapidly developing industrial cities in China. In recent years its rapid economic development has brought great prosperity to the Pearl River Delta (PRD) region, but has also given rise to a wide variety of environmental problems. The current level of lead (Pb) contamination (75–926 mg/kg) in the surface environment of Guangzhou remains a major concern, even though the use of leaded petrol in the city was banned in 1997. The Pb isotope ratios ( 206Pb/ 207Pb min-max : 1.1612–1.1961 and 208Pb/ 207Pb min-max : 2.4495–2.4838) of the urban dusts from unconfined (road dusts and gully sediments) and relatively confined (vehicular tunnel) settings in Guangzhou remains in a relatively narrow range, comparable with those of the regional natural and anthropogenic sources. This study highlights the inherent shortcomings of the Pb isotope fingerprinting technique for provenancing Pb sources, as both the target media (urban dusts) and potential sources have similar and highly radiogenic Pb isotope values. This could not only lead to an overestimation of the effectiveness of phasing-out of leaded petrol, but also an underestimation of the ever-increasing relative contributions from other potential sources of pollution, including coal combustion, industrial emissions of local Pb-ores and non-additive Pb contents of crude oils. Re-suspended Pb-bearing particulates deposited from early vehicular exhaust emission of leaded petrol with distinctly low Pb isotope compositions are still an important source of Pb pollution in the region.