Mapping airborne lead contamination near a metals smelter in Derbyshire, UK: spatial variation of Pb concentration and ‘enrichment factor’ for tree bark

Abstract

Samples of tree bark, collected over an area of 4 km2 near a small non-ferrous metals smelter in Derbyshire, UK, were analysed for Pb and Al by inductively coupled plasma atomic emission spectroscopy (ICP-AES). Analyte concentrations varied from 100 to over 25,000 mg kg-1 and 5 to 1000 mg kg-1, respectively. While an inverse relationship between the Pb content of bark and distance from the smelter was observed, concentrations fluctuated, indicating a variability in sample collection efficiency and problems in standardization. To overcome these effects, the Pb/Al ratio was calculated and subsequently normalized to the average Pb/Al ratio in continental crust (0.00015). On the assumption that the time-averaged concentration of airborne Al in this area is relatively constant and derived principally from wind-blown soil, the measurement represents an anthropogenic 'enrichment factor' (PbEF). PbEF varied from 10,000 to over 1,000,000, and showed a consistent reduction with distance from the smelter. Isolines of equal PbEF were subsequently defined on a map of the sampled area. Pb contamination was greatest in the vicinity of the smelter, and preferential transport along the NW-SE axis of the valley (in which the smelter is situated) was observed. The use of enrichment factors thus proved valuable in defining the relative level of airborne-derived Pb pollution.

Microscopic and chemical studies of metal particulates in tree bark and attic dust: evidence for historical atmospheric smelter emissions, Humberside, UK

“…Ti, Al, Sc) in the particulate deposition, and this ratio is then normalised to the ratio of those elements in the Earth's crust. Both Bellis et al 20 and…”

“…In addition, Bellis et al 20 suggested that the EF factor in bark should equal the time-averaged EF in air, assuming that the contributions via the soil solution are insignificant compared with airborne inputs. The major non-anthropogenic input of particulate deposition from the air is soil dust, hence the use of crustal values 20 . However, data from a geochemical survey for topsoil throughout this region of eastern England shown in Figure 1 were available 22 .…”

The use of Scots pine (Pinus sylvestrisL.) bark as a bioindicator for environmental pollution monitoring along two industrial gradients in the Kemi–Tornio area, northern Finland

“…Tree bark has also been used as an indicator for metal pollution emitted by traffic [12], as well as in the determination of isotope ratios, such as 206 Pb/ 207 Pb and 235 U/ 238 U emitted from a nuclear fuel fabrication plant [13,14]. In Finland, the Finnish Forest Research Institute has used Scots pine bark samples in the nationwide monitoring of atmospheric heavy-metal deposition [15].…”

The Health Status of Southern Children: A Neglected Regional Disparity

“…[21][22][23] It has continued to be used as an essential tool in defining the epidemiology of a wide range of infectious diseases [24][25][26][27][28] and is evolving as an important approach to environmental and other areas of epidemiology. [29][30][31][32][33][34][35][36][37] Its relevance to a broad range of health issues such as diabetes, 38 childhood lead poisoning, 39 pediatric burn injuries, 40 fertility, 41 cancer screening, 42 general chronic disease prevention, 43 and health services research 44 is also unfolding.…”