Neurotoxic Effects Of Childhood And Adolescent Blood Lead Levels

Background Lead has long been established as a potent neurotoxin, childhood being a key period of exposure due to rapid development at that stage in life. While lead is known to cause harmful health effects in the entire population, it is known to particularly damage the developing nervous system in children and potentially interfere with behavioral development. In 2001 a small cohort of children were identified with elevated blood lead level in Montevideo, Uruguay. Objectives This study investigated whether 2001 blood lead levels (BLL\u27s) or current (2011) BLL\u27s have had an effect on the behavioral outcomes in this group of adolescents. Methods A cohort study of 60 adolescents (mean age 15.2 years) from Montevideo was identified in 2001. Children with elevated BLL\u27s in 2001 (mean 2001 BLL= 13.2 μg/dL, SD= 5.2) were re-identified and tested for current (2011) BLL\u27s (mean 2011 BLL= 4.2 μg/dL, SD= 2.7) using atomic absorption spectrometry. The Child Behavior Checklist, a standardized assessment of behavioral problems, was administered to the adolescents. Linear regression was used to assess the relationship between 2001 BLL\u27s, current BLL\u27s, and the behavioral outcomes. Results 2001 BLL\u27s were found to be significantly associated with total problem behavioral score (β=0.98, 95% CI= 0.12-1.85) as well as the social (β=0.80, 95% CI= 0.20-1.40) and externalizing (β=0.93, 95% CI= 0.08-1.78) problem subscales when controlling for current (2011) BLL\u27s and age. 2011 BLL\u27s were not found to be significantly associated with behavioral outcomes. Additionally, 2011 BLL\u27s were found to be significantly lower than 2001 BLL\u27s (Wilcoxon paired test p= 1.90E-8). Conclusion This study confirms evidence that increased childhood exposure to lead is associated with subsequent negative behavioral outcomes, and suggests that childhood lead exposure has a stronger impact on behavioral outcomes than current exposure levels. Additionally, BLL\u27s have been significantly reduced since 2001 in this population

Spatial distribution of trace metals in urban soils and road dusts : an example from Manchester, UK

Urban soil quality is of concern under current UK contaminated land legislation in terms of potential impacts on human health, due to the legacy of industrial, mining and waste disposal activities and the fact that soils can act as a sink for potentially harmful substances (PHS) in the urban environment. As part of the the Geochemical Baseline Survey of the Environment (G-BASE) project of the British Geological Survey (BGS), 27 UK cities have been surveyed to establish baselines and assess the quality of urban soils. The G-BASE soil geochemical dataset for Manchester forms the basis of this project. Another medium that is a likely sink for PHS in urban environments is road dust sediment (RDS). RDS forms as an accumulation of particles on pavements and road surfaces, and has been shown to be both spatially and temporally highly variable in composition, as it is more susceptible to remobilisation and transport. RDS has been documented as carrying a high loading of contaminant species, including significant amounts of trace metals. Geochemical data from both soils and RDS, despite having different properties, are essential for environmental assessment in urban areas. Although studies of PHS in RDS and soils have been published, little is known about the spatial, geochemical and mineralogical linkages between these two media. The aim of this research is to define and establish these linkages, and produce novel mineralogical data on the PHS–particulate relationships within soils and RDS

Using geological and geochemical information to estimate the potential distribution of trace elements in Scottish groundwater

There are currently few reliable data available for the concentrations of trace elements in Scottish groundwaters. A new project Baseline Scotland, jointly funded by the British Geological Survey (BGS) and the Scottish Environment Protection Agency (SEPA), seeks to improve the data availability and general understanding of the chemistry of Scotland’s groundwater. However, this is a major undertaking and these new data will take several years to collect and interpret across the whole of Scotland. In the interim, SEPA have asked BGS to use their existing knowledge and data to give a rough estimate of where certain elements are more likely to be elevated in groundwater. This information will be used to help focus future monitoring and give background for Baseline Scotland. Predicting trace element concentrations is difficult, in part due to lack of knowledge on the distribution of mineral phases, the reactivity of different minerals and the geochemical environment, particularly the redox status. This report scopes the potential scale of naturally elevated trace elements in Scottish groundwater, in particular those elements that are potentially harmful to health: e.g. aluminium, arsenic, barium, cadmium, chromium, lead, manganese, nickel, uranium and zinc. The problems and limitations of prediction are discussed in the report and this work does not replace a proper assessment based on actual chemical analyses of groundwater. The method uses information on the geochemistry of the Scottish environment derived from the most comprehensive geochemical data set for Scotland, the BGS Geochemical Baseline Survey of the Environment (G-BASE), combined with the limited data available on the chemistry of Scottish groundwaters. The conditions under which each of the elements can become elevated in groundwater are discussed and the geological and geochemical information interpreted to produce a series of maps highlighting areas where each trace element may be elevated in groundwater relative to the Scottish average. The maps are based primarily on the 1:625 000 scale bedrock geology map of Scotland. In order to make the scheme and the maps simple and manageable, we have used the same numbers to describe the individual rock units (1 to 114) that are usedd on the Geological map of the UK (Solid Geology): North sheet. Some rock units have been subdivided, and other small areas highlighted where additional information is known, either from G-BASE or previous studies. After assessing the results of the exercise the following conclusions can be drawn: 1. The study has provided a useful summary of geochemical information for trace elements in Scotland, and detail the conditions in which these elements may become elevated in groundwater. This provides essential background to the Baseline Scotland project, which aims to improve the availability of groundwater chemistry data and the general understanding of the chemistry of Scotland’s groundwater. 2. The predictions can be used as a first pass to help focus and prioritise additional monitoring and for helping to interpret groundwater chemistry data from different areas. The predictions are only preliminary and will be modified in the future by detailed groundwater sampling and interpretation. There are several caveats: • For all of the trace elements considered, the lack of available groundwater chemistry data with detailed analysis of trace elements, and their restricted spatial distribution, means that it is not possible to rigorously test whether the groundwater quality predictions are accurate or not. • More groundwater chemistry data are available for three elements, barium, manganese and zinc, allowing a rudimentary test of the predictive maps. For barium the prediction appears to work well, but there is poor correlation for zinc. For manganese, some correlation is evident, but the complexity and variability of local conditions are such that much variation is observed. • This approach, using broad, national scale geological and environmental data, cannot account for the complexity of the controls on groundwater chemistry: i.e. the heterogeneous nature of the Scottish environment, not least the aquifer mineralogy and glacial history, and the complex behaviour of trace elements in groundwater, determined by aspects such as flow pathways, residence times, and the geochemical environment (for example, oxidising/reducing or acidic/alkaline conditions). In summary, this approach appears to be a useful first step in trying to estimate the likely distribution of trace elements in Scottish groundwater, in the absence of much reliable groundwater quality data. However, only by systematically collecting reliable groundwater chemistry data, across different aquifers and regions and from different depths, can the variation in trace elements in groundwater across Scotland be understood. Careful modelling and interpretation of these new data in the context of the geology and environmental conditions will help make future predictions of groundwater quality more reliable and provide reference information for the Water Framework Directive

Maximising multiple benefits from sustainable drainage systems: identification and decision support

This paper describes efforts in Scotland UK to assess urban diffuse pollution sources, pathways and sinks; to establish mitigation measures, which can address waterborne urban pollution and also provide multiple benefits. The paper will describe the results from an extensive review exercise, which culminated in the development of a new decision support tool. The tool is intended to help urban planners and water managers tackle urban diffuse pollution with mitigation measures, which could provide multiple environmental and societal benefits, in addition to delivering pollution mitigation

The geochemical quality of soils in the Clyde basin, Scotland, UK : main controls and anthropogenic impacts [abstract only]

Recently, the British Geological Survey’s (BGS) Geochemical Baseline Survey of the Environment (G-BASE) project carried out extensive surveys of rural and urban soil quality in the River Clyde catchment (Clyde basin) on the west coast of Scotland. The Clyde basin is interesting as it extends from a rural upland environment in the south, to the River Clyde estuary in the north. The catchment contains an historic lead mining area known as Leadhills that was active until the mid 20th century. In addition, the estuary and lower reaches of the river formed the transport and shipping links that drove the development of Scotland’s main conurbation – the city of Glasgow, which is centred on the River Clyde. Although heavy industry and mining have now declined, the newly available G-BASE soil datasets demonstrate the impacts of urbanisation and the post-industrial legacy of the Glasgow conurbation as well as of historical mining activities on environmental quality

Assessing soil and stream water geochemistry in the Clyde Basin, Scotland, UK.

The Clyde Basin comprises the River Clyde catchment, west coast of Scotland, UK including the Glasgow conurbation, a major industrial centre in the past. Over recent years, the British Geological Survey has carried out regional-scale topsoil (5 – 20 cm) and surface water geochemical surveys across the Clyde Basin. The samples were analysed for total concentrations of approximately 50 parameters. The results show the influence of geology, land use, current and former mining activity, industry and urbanisation on the chemical quality of soil and surface water in the region

3D geological models and their hydrogeological applications : supporting urban development : a case study in Glasgow-Clyde, UK

Urban planners and developers in some parts of the United Kingdom can now access geodata in an easy-to-retrieve and understandable format. 3D attributed geological framework models and associated GIS outputs, developed by the British Geological Survey (BGS), provide a predictive tool for planning site investigations for some of the UK's largest regeneration projects in the Thames and Clyde River catchments. Using the 3D models, planners can get a 3D preview of properties of the subsurface using virtual cross-section and borehole tools in visualisation software, allowing critical decisions to be made before any expensive site investigation takes place, and potentially saving time and money. 3D models can integrate artificial and superficial deposits and bedrock geology, and can be used for recognition of major resources (such as water, thermal and sand and gravel), for example in buried valleys, groundwater modelling and assessing impacts of underground mining. A preliminary groundwater recharge and flow model for a pilot area in Glasgow has been developed using the 3D geological models as a framework. This paper focuses on the River Clyde and the Glasgow conurbation, and the BGS's Clyde Urban Super-Project (CUSP) in particular, which supports major regeneration projects in and around the City of Glasgow in the West of Scotland

Mapping the water chemistry of the Clyde Basin drainage network

Mapping the chemistry of stream and river water across the Clyde Basin serves both to characterise the water quality and assess the dominant controls. Surveys of the Clyde drainage network, undertaken between 2003 and 2010, have generated data encompassing rural and urban streams, rivers, and estuarine water. Mapping displays the large spatial variability in chemical composition across the Basin and the varying influences of controls such as rainfall, land cover and geology. They also display the chemistry of the urban area within the context of the wider drainage network. This presentation highlights the upcoming production of an online atlas and database of surface-water chemistry which characterises the Clyde drainage network and provides a new resource for stakeholder organisation

Understanding chromium behaviour in COPR-impacted sediments in the Polmadie Burn, Glasgow.

From ~1830-1968, one of the world’s largest Cr chemical factories operated in Rutherglen, SE Glasgow, Scotland. During this time ~2.5 million tonnes of chromite ore processing residue (COPR) was produced and used mainly as landfill, leading to widespread contamination of nearby land, surface water and groundwater. Hexavalent chromium (Cr(VI)) is highly toxic and carcinogenic and is present in COPR at ~1% w/w. Although some of the contaminated sites have been remediated, Cr(VI) is still readily detected in burn-side soils, sediments and surface waters of the Polmadie Burn, which flows into the River Clyde, Glasgow. This project seeks to determine the biogeochemical and environmental factors that influence the preservation of Cr(VI), its transport and its bioaccessibility