Stable Lead Research Articles

混合塩を用いた塩化揮発処理による鉛汚染土壌の浄化

In the previous study, the authors have investigated the mechanism and the optimum condition of lead removal from contaminated soil by application of sequential treatment of chlorination and warm water extraction. Lead was successfully removed from soil at lower temperature than conventional heat treatment on soil. However, relatively large amount of mixed chloride was required.In this paper, new soil remediation technique was investigated to overcome the disadvantage of the sequential treatment. In the new method, stable lead complex in soil was chlorinated to be PbCl2 by HCl gas emitted by reaction between SiO2 and MgCl2-CaCl2-KCl mixed chloride. Because of high vapor pressure of PbCl2, lead was eliminated from soil by chlorination volatilization. Lead removal was promoted by enhancing volatilization of PbCl2 by introducing carrier gas and by optimizing mixed chloride composition. Residual lead content was reduced more effectively with small amount of mixed chloride than the sequential treatment.

Is there a chronological record of atmospheric mercury and lead deposition preserved in the mor layer (O-horizon) of boreal forest soils?

The organic horizon (the mor layer) of podzolized boreal forest soils has accumulated atmospheric fallout of mercury and lead over centuries, resulting in current concentrations close to levels where negative effects on soil biota are thought to occur. To what extent the pollution history is preserved in the stratigraphy of this horizon is not well known. In this study we asses whether the chronology of a large historic pulse of atmospheric pollution emitted from the Rönnskär smelter in northern Sweden, particularly between 1950 and 1980, is preserved within the stratigraphy of the mor layer, which is typically 5-cm thick. Vertical sub-sampling (⩽5 mm) of five mor profiles sampled along a 100-km pollution gradient away from the smelter are analyzed for mercury and lead concentrations, spheroidal carbonaceous particles from fossil fuel combustion (SCPs) and stable lead isotopes ( 206Pb/ 207Pb and 208Pb/ 207Pb). Their vertical distribution is compared with the temporal variations in atmospheric inputs reconstructed for the last ∼100 years from analyses of an ombrotrophic peat core and a varved lake sediment core sampled within a distance of 50 km of the smelter. The mor profiles situated ⩽12 km from the smelter record the pollution history of the smelter. There is a 20 to 40-times enrichment of Hg, Pb and SCP at the transition in the O-horizon from the F- to H-layer compared to the basal part and a distinct peak in the 206Pb/ 207Pb ratio (∼1.22) in the F-layer. The mor profiles situated outside the historical contamination range of the smelter (80 and 100 km away) record no obvious influence from the Rönnskär smelter, instead their vertical 206Pb/ 207Pb profiles follow the general regional pollution history in northern Sweden. We conclude that the mor layer preserves a record of atmospheric Hg, Pb and SCP inputs and due to low leaching rates this organic horizon serves as a semi-archive of atmospheric Hg and Pb pollution. We stress the need of including this property in the existing ‘black-box’ models predicting the fate of Hg and Pb within contaminated boreal forest soils.

Characteristics of trace elements and lead isotope ratios in PM 2.5 from four sites in Shanghai

PM 2.5 samples were collected in Shanghai at four sites with different typical land-uses. The sampling was done concurrently once per month from April 2004 to April 2005, and the ambient mass concentration, the elemental composition and the stable lead isotope ratios in these PM 2.5 samples were determined. The annual average concentrations of PM 2.5 samples at each site were 84 ± 30, 65 ± 20, 55 ± 18, and 41 ± 10 μg m −3, respectively, indicating there were severe air pollution levels in Shanghai. The enrichment factor was calculated for each element and the comparison and discussion of elements with significant anthropogenic contributions between Shanghai and Tokyo suggested that the major source of PM 2.5 in Shanghai was not traffic-derived emissions, but the stationary industrial contribution emitted from coal use. Moreover, the analysis of stable lead isotope ratios revealed only a slight difference within the samples at the four sites which fell well within the scope of coal composition difference, further confirming that the contribution from stationary industrial emissions to atmospheric lead pollution of PM 2.5 was very substantial in Shanghai.

Radioactive and radiogenic isotopes in sediments from Cooper Creek, Western Arnhem Land

Protection of the environment post-mining is a key objective of rehabilitation, especially where runoff and erosion from rehabilitated mine sites could potentially lead to contamination of the surrounding land and watercourses. As part of an overall assessment of the success of rehabilitation at the former Nabarlek uranium (U) mine, an appraisal of stable lead (Pb) isotopes, radionuclides and trace metals within sediments and soils was conducted to determine the off site impacts from a spatial and temporal perspective. The study found localised areas on and adjacent to the site where soils had elevated levels of trace metals and radionuclides. Lead isotope ratios are highly radiogenic in some samples, indicating the presence of U-rich material. There is some indication that erosion products with more radiogenic Pb isotope ratios have deposited in sediments downstream of the former ore body. However, there is no indication that the radiogenic erosion products found on the mine site at present have significantly contaminated sediments further downstream of Cooper Creek.

Sources and chronology of fifteen elements in the sediments of lakes affected by metal deposition in a mining area

Sources and chronologies of metal contamination were studied in sediment cores of three lakes of the Rouyn-Noranda mining area (Quebec, Canada) affected by atmospheric deposition of anthropogenic contaminants. One of the three lakes also received acid mine drainage. The sediments were dated using 210Pb and 137Cs and analysed for stable Pb isotope ratios and for total concentrations of 15 elements (Ag, Al, Au, Ca, Cu, Cd, Fe, Hg, Mn, Ni, P, Pb, S, Ti, Zn). Stable lead isotopic signatures helped to determine the quantitative contributions of different industrial Pb sources to our sampling sites. This source apportionment showed the dominant influence of the Rouyn-Noranda copper smelter in airborne Pb emissions for the decades following 1926, when industrialization began in the region. The smelter source had a low ratio of 206Pb/207Pb ranging between 0.90 and 1.05, as typical of the Abitibi Archean sulphides. The relationships between element (metal) sedimentary fluxes and anthropogenic Pb fluxes allowed us to infer the origin of the anthropogenic source. These relationships strongly suggest that the copper smelter was (and may still be) an atmospheric source of Cd, Cu, Pb, Zn, Ag and Hg to the surrounding lakes. Our study indicates that the efforts made by the Rouyn-Noranda copper smelter to reduce airborne emissions of metals have been translated in reduced atmospheric metal loadings to the surrounding lakes.

A lead isotopic assessment of tree bark as a biomonitor of contemporary atmospheric lead

The outermost bark layer of trees, predominantly Scots pine ( Pinus sylvestris), was sampled at 82 non-urban locations from six arbitrarily designated areas (Northwest, Northeast, Central Highlands, Central and East, Central and Southwest, Southeast), throughout Scotland during 2002–2003 and analysed for lead concentration and stable lead isotopes by flame atomic absorption spectrometry (AAS) and inductively coupled plasma-mass spectrometry (ICP-MS), respectively. The mean lead concentration and mean 206Pb/ 207Pb ratio (± 1 standard deviation, SD) for bark samples from the areas were as follows: Northwest (8.0 mg kg − 1 , 1.121 ± 0.014, n = 17), Northeast (8.9 mg kg − 1 , 1.117 ± 0.012, n = 12), Central Highlands (11.3 mg kg − 1 , 1.130 ± 0.010, n = 11), Central and East (35.3 mg kg − 1 , 1.120 ± 0.007, n = 10), Central and Southwest (20.6 mg kg − 1 , 1.125 ± 0.018, n = 22) and Southeast (34.4 mg kg − 1 , 1.120 ± 0.005, n = 10), with an overall mean lead concentration of 18.5 mg kg − 1 (range 0.6–146 mg kg − 1 , median 8.4 mg kg − 1 ) and an overall mean 206Pb/ 207Pb ratio of 1.122 ± 0.014 (range 1.089–1.168, median 1.122). The overall mean 206Pb/ 207Pb ratio for bark was therefore significantly lower ( p < 0.01, t test) than the mean atmospheric 206Pb/ 207Pb ratio of 1.154 ± 0.006 (range 1.144–1.167, n = 50) and 1.154 ± 0.010 (range 1.134–1.171, n = 26) as determined in rainwater collected routinely at Glensaugh, Central Highlands, during 2002 and 2003, respectively. The bark 206Pb/ 207Pb values, 90% of which lay between 1.10 and 1.14, were more akin to those recorded for the atmosphere (via rainwater, atmospheric particulates, moss, etc.) at various locations throughout Scotland during the 1990s, a decade over which the use of leaded petrol (mean 206Pb/ 207Pb ratio = 1.076 ± 0.011) declined markedly before its complete withdrawal in 2000. This strongly suggests that the lead content and isotopic composition of tree bark from Scots pine, which reputedly sheds its outer layers every couple of years or so, reflect exposure to atmospherically deposited lead (in the atmosphere or soil) over a much longer time period than just the previous 2–3 years of exposure to contemporary atmospheric lead. The possible influence of soil lead upon tree bark through external attachment was not observed in a comparative sub-set study of 27 paired bark (mean 206Pb/ 207Pb ratio = 1.122 ± 0.016) and surface (0–2 cm) soil (mean 206Pb/ 207Pb ratio = 1.145 ± 0.022) samples, in only six cases (i.e. 22%) of which did the corresponding 206Pb/ 207Pb ratios agree within ± 2 SD. Likewise, bark 206Pb/ 207Pb values exhibited no discernible trend with distance from the nearest road, with similar average values for 0–20 m (1.123 ± 0.015, n = 34) and 20–700 m (1.122 ± 0.012, n = 48), although the corresponding mean (and median) lead concentration of 23.5 (10) mg kg − 1 vs. 14.9 (7.5) mg kg − 1 was slightly higher for the former. The influence of airborne dusts from waste deposits related to former mining/smelting of Wanlockhead/Leadhills lead ores ( 206Pb/ 207Pb = 1.170 ± 0.003) could be seen, however, in the sycamore bark lead concentrations of up to 3050 mg kg − 1 and 206Pb/ 207Pb ratios (1.168–1.171) observed at a distance of 0.5 km away.

Stable Mononuclear Lead(III) Compound: A Lead‐Centered Radical

Stable Mononuclear Lead(III) Compound: A Lead‐Centered Radical

Local recipes or distant commodities? Lead isotope and chemical compositional analysis of glaze paints from the Salinas pueblos, New Mexico

For nearly four hundred years, Pueblo potters in the Rio Grande Valley of New Mexico produced technologically innovative glaze-decorated bowls and exchanged them widely among different villages. While potential sources of lead ores used to make glaze paints are found throughout the Rio Grande Valley region, researchers have only recently begun to identify which ore sources potters exploited and to understand the social and economic factors underlying patterns of ore resource use. In this paper we use stable lead isotope and electron microprobe analysis of glaze paints on Rio Grande Glaze Ware made at two Salinas pueblos to identify ore sources and glaze recipes used by their potters. Despite some isotopic overlap of ore sources, the lead isotope data point to regular exploitation of ores from the Socorro area of the southern Rio Grande. Salinas potters apparently used other sources as well, and likely mixed ores from different sources. We also identify four local glaze recipes that appear to incorporate multiple ore sources, suggesting that Salinas potters obtained raw ores rather than finished glaze paints.

Sequential extraction procedure for determination of uranium, thorium, radium, lead and polonium radionuclides by alpha spectrometry in environmental samples

A sequential extraction technique was developed and tested for common naturally-occurring radionuclides. This technique allows the extraction and purification of uranium, thorium, radium, lead, and polonium radionuclides from the same sample. Environmental materials such as water, soil, and biological samples can be analyzed for those radionuclides without matrix interferences in the quality of radioelement purification and in the radiochemical yield. The use of isotopic tracers (232U, 229Th, 224Ra, 209Po, and stable lead carrier) added to the sample in the beginning of the chemical procedure, enables an accurate control of the radiochemical yield for each radioelement. The ion extraction procedure, applied after either complete dissolution of the solid sample with mineral acids or co-precipitation of dissolved radionuclide with MnO2 for aqueous samples, includes the use of commercially available pre-packed columns from Eichrom® and ion exchange columns packed with Bio-Rad resins, in altogether three chromatography columns. All radioactive elements but one are purified and electroplated on stainless steel discs. Polonium is spontaneously plated on a silver disc. The discs are measured using high resolution silicon surface barrier detectors. 210Pb, a beta emitter, can be measured either through the beta emission of 210Bi, or stored for a few months and determined by alpha spectrometry through the in-growth of 210Po. This sequential extraction chromatography technique was tested and validated with the analysis of certified reference materials from the IAEA. Reproducibility was tested through repeated analysis of the same homogeneous material (water sample).

The fabrication of lead dioxide layers on a titanium substrate

It is shown that stable and active lead dioxide on titanium anodes (including mesh electrodes) may be fabricated by appropriate pretreatment of the substrate and a strategy involving the anodic deposition of two PbO 2 layers—a thick underlayer with the lead dioxide doped with fluoride and iron and a top layer with the lead dioxide doped with bismuth. Periods on open circuit, especially in solutions containing an oxidisable organic or inorganic species must, however, be avoided since all forms of PbO 2 are reducible unless protected by an anodic current; the rates of the reduction does depend on the medium, the dopants in the PbO 2 and the morphology of the layer. It is also shown that, as at gold substrates, the morphology of the PbO 2 layer on titanium (consequently, their properties including adhesion and electrocatalytic activity) depend strongly on the deposition conditions including the bath composition (including Pb(II) concentration, acid concentration, concentration and choice of dopant ion), temperature, current density and deposition charge.

Size-dependent spectroscopic, optical, and electrical properties of PbSe nanoparticles

Stable crystalline Lead Selenide nanoparticles (PbSe NPs) were prepared with a cubic (sphalerite) phase in polyvinyl alcohol (PVA) matrix. Moreover, XRD was used to characterize the PbSe NPs in PVA. The size were controlled by Pb:Se ions ratio in which the particle size was found to be inversely proportional to this ratio up to 16:1. FT-Raman and FT-IR measurements indicated the decrease of crystallization of PVA due to doping with PbSe NPs as indicated by the appearance of a peak at 1124 cm-1 that increases by size reduction of PbSe NPs. The Photoluminescence and electrical measurements monitored the interaction of PbSe NPs with PVA which increased by decreasing the particle size. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Flux Rates of Atmospheric Lead Pollution within Soils of a Small Catchment in Northern Sweden and Their Implications for Future Stream Water Quality

It is not well-known how the accumulated pool of atmospheric lead pollution in the boreal forest soil will affect the groundwater and surface water chemistry in the future as this lead migrates through the soil profile. This study uses stable lead isotopes (206Pb/207Pb and 208Pb/ 207Pb ratios) to trace the transport of atmospheric lead pollution within the soil of a small catchment and predict future lead level changes in a stream draining the catchment. Low 206Pb/207Pb and 208Pb/207Pb ratios for the lead in the soil water (1.16 +/- 0.02; 2.43 +/- 0.03) and streamwater (1.18 +/- 0.03; 2.42 +/- 0.03) in comparison to that of the mineral soil (>1.4; >2.5) suggest that atmospheric pollution contributes by about 90% (65-100%) to the lead pool found in these matrixes. Calculated transport rates of atmospheric lead along a soil transect indicate that the mean residence time of lead in organic and mineral soil layers is at a centennial to millennial time scale. A maximum release of the present pool of lead pollution in the soil to the stream is predicted to occur within 200-800 years. Even though the uncertainty of the prediction is large, it emphasizes the magnitude of the time lag between the accumulation of atmospheric lead pollution in soils and the subsequent response in streamwater quality.

Atmospheric lead fallout over the last century recorded in Gulf of Lions sediments (Mediterranean Sea)

Six marine sediment cores from the Gulf of Lions continental slope (700–1700 m water depth) were analyzed for stable lead isotopes and 210Pb geochronology in order to reconstruct lead atmospheric fallout pattern during the last century. The detrital lead contribution is 25 μg g −1 and the mean sediment anthropogenic inventory is 110 ± 7 μg cm −2, a little bit higher than atmospheric deposition estimate. Anthropogenic lead accumulation in sediments peaked in early 1970s (1973 ± 2) in agreement with lead emissions features. For the period 1986–1997, the sediment signal also reflect the decrease of atmospheric lead described by independent atmospheric fallout investigations. The anthropogenic Pb deposition in the late 1990s was similar to the 1950s deposition, attesting thus of the output of European environmental policies.

Estimating the Mean Residence Time of Lead in the Organic Horizon of Boreal Forest Soils using 210-lead, Stable Lead and a Soil Chronosequence

Knowledge about the residence time of lead in the organic horizon (mor layer; O-horizon) overlaying forest mineral soils is important for the prediction of past and future lead levels in the boreal ...

Sources and mobility of thallium and indium in Canadian lakes

Chemical and biological reactions occurring in lake sediments (early diagenesis) can influence the vertical distribution of trace metals and compromise the use of sediment profiles as historical records of anthropogenic metal pollution. There is thus a need to evaluate the importance of post-depositional redistribution of metals in sediments. Large uncertainties also exist concerning sources of metal emissions. In this study, we use porewater and solid phase measurements to determine the post-depositional mobility of thallium and indium in Canadian Shield lakes and to establish atmospheric T1 and In sources and deposition chronology. Two lakes exposed to different emission sources of trace metal pollution were chosen for the study. One, L. Tantar6, is located in an ecological reserve about 40 km from Qu6bec City (about 520000 inhabitants); according to prevalent wind trajectories, this lake is under the influence of atmospheric emissions from the Midwest-Great Lakes and Eastern regions of the USA, as well as from cities located along the St. Lawrence River. The other one, L. Vose, is located 25 km downwind from an important smelter in the mining city of Rouyn-Noranda. The uninhabited drainage basins of these two lakes have not been affected by wildfires or wood harvesting for at least 100 years. Thus, atmospheric deposition has been the only input of atmospheric T1 and In to these basins. Sediment cores were obtained from the deepest part of each lake and analyzed for total T1 and In. Porewaters were collected at the coring sites by in-situ dialysis and analyzed for T1, In, as well as for major ions, sulfide, organic carbon and pH which are needed for speciation calculations. The porewater and sediment geochemical data were used, together with information on infaunal benthos, in the diagenetic reaction-transport equation which was solved numerically for net reaction rates as a function of sediment depth with the code PROFILE. This information was used to estimate the importance of diagenetic processes in shaping the solid phase T1 and In profiles, to estimate the deposition chronology of these metals and to identify the diagenetic reactions involving these metals. Comparison of T1 and In deposition chronology with those of other contaminants (e.g. PAHs, stable lead isotopes) measured at the same sites allowed identification of the main atmospheric sources of TI and In. Our results suggest that T1 and In are useful tracers for atmospheric emissions from coal combustion and metal smelters, respectively.

A stable lead isotopic investigation of the use of sycamore tree rings as a historical biomonitor of environmental lead contamination

The validity of the use of sycamore ( Acer pseudoplatanus) tree-rings for the reconstruction of atmospheric lead pollution histories was investigated. Tree cores spanning 1892–2003 were collected from several sycamores from the eastern shore of Loch Lomond, Scotland, an area with no local point sources of lead emission. The lead concentration and 206Pb/ 207Pb profiles of the Loch Lomond region cores were compared with corresponding data for the 210Pb-dated loch sediment, and also with data for moss of known age from a Scottish herbarium collection. Two of the seven sycamore cores showed the same lead concentration trend as the lead flux to the loch, the rest having no similarity to either each other or the loch sediment record. Two further sycamore cores showed some similarity in their temporal 206Pb/ 207Pb trends to those seen in the sediment and moss records, but only in part of their profiles, whilst the 206Pb/ 207Pb ratios of the other sycamore cores remained relatively unchanged for the majority of the time covered, or exhibited an opposite trend. The 206Pb/ 207Pb ratios of the tree cores were also mostly higher than those of the previously established records for any given time period. Tree cores covering 1878–2002 were also collected along transects from Wanlockhead and Tyndrum, two areas of former lead mining and smelting associated with distinct 206Pb/ 207Pb ratios of 1.170 and 1.144, respectively. The Wanlockhead tree cores exhibited a generally decreasing trend in lead concentration with both time and distance from the lead mine. The characteristic 206Pb/ 207Pb ratio of 1.170 was observed in samples close to the mine but a decrease in the influence of the mine-derived lead was observed in more distant samples. The tree sampled at Tyndrum showed elevated lead concentrations, which decreased with time, and a fairly constant 206Pb/ 207Pb ratio of ∼ 1.15 reflecting input from the mine, features not observed in any other trees along the transect. Overall the data suggest that sycamore tree-ring analysis is an unsuitable method for obtaining records of historical lead deposition in areas with no large local lead input, although it can reveal some information about the temporal and spatial influence of point source emitters. The unsuitability probably arises from the number of active annual rings in a single year, the post-uptake radial translocation of elements, the relative importance of the different routes of uptake, and the soil depth(s) from which trees draw nutrients.

Developments in Conventional Pacing – Harmful Effects of Pacing the Right Ventricular Apex and Strategies to Avoid it

Introduction Since the inception of cardiac pacing, the favoured site has been the right ventricular apex (RVA). The RVA is popular as it is usually straightforward, provides stable lead position and is associated with few complications. A critical re-evaluation of this practice is occurring, however. There is accumulating evidence that RVA pacing causes adverse effects on left ventricular (LV) function,1,2-4 and is associated with an increased risk of atrial fibrillation (AF)5,6 and death.7

Chronicling a Century of Lead Pollution in Mexico: Stable Lead Isotopic Composition Analyses of Dated Sediment Cores

Analyses of lead isotopic compositions (204Pb, 206Pb, 207Pb, and 208Pb) of dated sediment cores from two coastal estuaries and two inland lakes chronicle the predominance of industrial lead emissions in Mexico over the past century. These isotopic ratios exhibit a shift in composition from the turn of the previous century (1900) that corresponds with measurable increases (from 2- to 10-fold) in lead concentrations in the cores above their baseline values (3-22 microg/g)--both changes are consistent with the development of Mexican lead production for export and the manufacture of tetraethyl lead additives for Mexican gasolines. While subsequent changes in lead concentrations in the cores correspond with calculated emissions from the combustion of leaded gasoline in Mexico, isotopic compositions of the cores remain relatively constant throughout most of the 1900s (e.g., 206Pb/207Pb = 1.200 +/- 0.003; 208Pb/207Pb = 2.463 +/- 0.004). That isotopic constancy is attributed to the widespread pollution from lead production in Mexico and the dispersion of some of that lead used as an additive in Mexican gasolines.

Apparent discrepancy in contamination history of a sub-tropical estuary evaluated through 210Pb profile and chronostratigraphical markers

Zn and Cd concentrations, stable lead isotopes and 210Pb-derived chronology were determined in a sediment core sampled at Sepetiba Bay (South-eastern Brazil). During the last decades, the bay’s watershed has been modified by the increase of industrial activities and human interventions. In particular, Zn and Cd ore treatment plants were built near the coast in 1960 and 1970, respectively, and water has been diverted from the adjacent Paraíba do Sul River watershed since 1950. The core collected at shallow depth near the industrial area exhibits four successive events: (i) at 50 cm depth, a change in the 206Pb/ 207Pb ratio from about 1.162 to more than 1.18 might be the result of the São Francisco Channel opening and water diversion from Paraíba do Sul river; (ii) at 40 cm depth, Zn concentration starts to increase (up to 0.8 mg g −1) (iii) above 30 cm depth, relatively high Cd concentrations (up to 1.6 μg g −1) are observed and (iv) at 16 cm depth, change in unsupported 210Pb slope is probably related to a waste dam built to prevent strong metal contamination in the bay. Sediment accumulation rates evaluated by Zn and Cd profiles used as time-markers are higher than those calculated from 210Pb-based chronology models. Using the constant initial concentration (CIC) model both events are supposed to date back to about 1884 and 1902, respectively, while using the constant rate of supply (CRS) model it shifts to about 1925 and 1935. Such discrepancies are probably assigned to the fact that these models do not take into account site-specific local sedimentation dynamics. In the study area, particles deposition seems to be controlled by enrichment with unsupported 210Pb transported by runoff from a mangrove flat bank. Chronology derived from a model that assumes an exponential increase of the initial 210Pb activity fits well with the estimated rates obtained from historical events.

Left heart atrial and ventricular epicardial pacing through a left lateral thoracotomy in children: a safe approach with excellent functional and cosmetic results☆

Left heart atrial and ventricular epicardial pacing through a left lateral thoracotomy is an alternative approach for lead insertion in children, avoiding venous access complications and right ventricular stimulation, without compromising sporting or musical activities. We analyzed the survival and performance of left atrial and left ventricular epicardial pacing leads, and present mid-term follow-up data. Seventy-five bipolar steroid eluting pacing leads (Medtronic CapSure Epi 4968) were implanted in 41 children, aged 8.6+5.1 years. Pacing systems included 34 DDDR and 7 VVIR. Pacing leads were inserted through a muscle-sparing left lateral thoracotomy, and sutured to the left atrial appendage or atrium, and to the left ventricle. The generators were buried behind the abdominal muscles or between the thoracic muscle layers. Congenital heart disease with previous cardiac surgery was present in 25 children. Indications for pacing were post-operative heart block (n=14), sinus node disease (n=13), congenital heart block (n=9), and various (n=5). Threshold values and measured data were obtained at 6-month intervals. The mean follow-up was 3.8+2.9 years. There was no mortality or major morbidity, with excellent functional and cosmetic results. Lead survival was 94 and 86% for atrial leads, and 97 and 86% for ventricular leads, at 1 and 5 years, respectively. There were five reoperations for lead fracture (n=2), insulation break (n=1), oversensing (n=1), and infection (n=1). Device reprogramming was required in three instances. In the absence of acute lead failure, mid-term follow-up shows very satisfactory and stable lead performance. Left heart atrial and ventricular epicardial pacing leads inserted through a left lateral thoracotomy demonstrate a high probability of survival, with favorable pacing characteristics, and optimal sensing thresholds at mid-term follow-up. Epicardial left heart pacing is reliable, and easy access can be achieved through a cosmetic and functional muscle-sparing left lateral thoracotomy.