Urban geochemistry: research strategies to assist risk assessment and remediation of brownfield sites in urban areas.

Urban geochemical maps of Wolverhampton and Nottingham, based on multielement analysis of surface soils, have shown distribution patterns of "total" metals concentrations relating to past and present industrial and domestic land use and transport systems. Several methods have been used to estimate the solubility and potential bioavailability of metals, their mineral forms and potential risks to urban population groups. These include sequential chemical extraction, soil pore water extraction and analysis, mineralogical analysis by scanning electron microscopy, source apportionment by lead isotope analysis and the development of models to predict metal uptake by homegrown vegetables to provide an estimate of risk from metal consumption and exposure. The results from these research strategies have been integrated with a geographical information system (GIS) to provide data for future land-use planning.

Dispersion of As and selected heavy metals around a coal-burning power station in central Slovakia.

A power station in central Slovakia emitted arsenic (As) in large quantities for over 30 years as a result of burning As-rich brown coal. Nowadays emissions of As are low. Over the lifetime of the plant's operation over 3000 tonne of As have been emitted into the environment. This paper aims to examine the concentrations of As in the soil around the power station, and also to investigate whether the coal burnt in the plant, and consequently the emissions from it, contained raised levels of six further heavy metals. Soil concentrations were compared to ground level air As concentrations predicted by an air dispersion model. Coal samples were taken from the power station and analysed to determine concentrations of As, Zn, Pb, Cu, Cr, Ni and Cd. Soil samples (n=113) were taken up to 12 km from the plant along a transect designed to follow the valley floor in which the power station is situated. Soil samples were analysed for concentrations of those elements for which coal was tested. Concentrations of As in coal were high (AM 518 mug/g). Those of other heavy metals were, in general, low. Concentrations of soil As were substantially raised in the near vicinity of the plant but decreased within 5 km to concentrations similar to those in the rest of the district. Overall, levels within 10 km of the plant were slightly above those recommended for residential levels in the UK. Soil concentrations of other heavy metals were higher in the vicinity of the plant but none, overall was raised. Comparison of results from a previous air dispersion model of ground level air arsenic concentrations showed a moderate correlation (r=0.6) between modelled and measured values. Over its period of operation the power plant has contributed to raised levels of soil As in the local soils, though not substantially of other elements. Though now airborne As emissions are controlled, concern remains regarding soil arsenic concentrations and fugitive emissions from the plant that could be contributing to exposure of the local population and of the workforce.

The influence of soil characteristics on the extractability of Cd, Pb and Zn in upland and moorland soils.

A study was undertaken to investigate the feasibility of using existing data sets of total soil metal concentrations and soil parameters, such as pH, to predict available metal concentrations on a regional or national basis. The attraction of such an approach is that it would provide valuable data for initiatives requiring information on the availability and mobility of metals in soils without the need for costly soil sampling and analysis. Ninety-seven topsoil and subsoil samples were collected from 6 soil series in a catenary sequence in north Wales to provide data for the development of an empirical model. These were analysed for total, 0.01 M CaCl2-extractable and porewater metal concentrations and for a range of soil properties including pH, solid and dissolved organic matter and cation exchange capacity. Regression analysis showed that, of the soil parameters measured, pH was the most important predictor variable for the estimation of CaCl2-extractable Cd, Pb and Zn. pH accounted for up to 86% of the variance in the proportion of 'total' metals which were extracted by CaCl2, a reagent that is commonly used to estimate plant uptake of elements. However, the relationships recorded between soil parameters and Kd (total metal/porewater metal) were much weaker, indicating that porewater metal concentrations can less readily be predicted from total soil metal concentrations and soil properties.

Contamination of surface soils, river water and sediments by trace metals from copper processing industry in the Churnet River Valley, Staffordshire, UK.

The impacts of a functional and a demolished copper processing works on the aquatic and terrestrial environment in the vicinity of the works was investigated by determining the levels of selected trace metals in river water, river sediments, channel margin sediments and overbank soils. Samples were taken at five sites within an area of the Churnet Valley in Staffordshire, where the River Churnet flows through the two works. Analysis of river water samples by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) has shown that only copper is present above background levels considered to typify uncontaminated rivers. Analysis of river sediments, channel margin sediments and overbank soils by nitric-perchloric acid digestion and Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) analysis has indicated contamination by arsenic, cadmium and copper in the vicinity of both works. Arsenic and copper are deposited primarily within the aquatic environment, although some contamination of the terrestrial environment by copper is also observed. Cadmium is deposited primarily within the terrestrial environment. The deposition of arsenic and copper in river and channel margin sediments respectively is also related to current and historical contamination.

Asphalt volcanism and chemosynthetic life in the Campeche Knolls, Gulf of Mexico.

In the Campeche Knolls, in the southern Gulf of Mexico, lava-like flows of solidified asphalt cover more than 1 square kilometer of the rim of a dissected salt dome at a depth of 3000 meters below sea level. Chemosynthetic tubeworms and bivalves colonize the sea floor near the asphalt, which chilled and contracted after discharge. The site also includes oil seeps, gas hydrate deposits, locally anoxic sediments, and slabs of authigenic carbonate. Asphalt volcanism creates a habitat for chemosynthetic life that may be widespread at great depth in the Gulf of Mexico.

Mechanisms of copper tolerance by Armeria maritima in Dolfrwyong Bog, north Wales--initial studies.

Preliminary field studies were carried out at Dolfrwynog Bog in July 2000. Replicate samples of water, Armeria maritima plants and the soils adhering to its roots were collected and analysed for copper. Concentrations of up to 6486 mg kg-1 of copper in the soils were recorded. Accumulation of copper by the plant as expressed by concentration factors (CF) show that it is acting mainly as a copper excluder. Of the copper that is taken up, most of it is retained within the roots with very little being transported to the shoots of the plant. Moreover, a further possible mechanism of tolerance is exhibited by the excretion of copper through its decaying leaves. Towards the use of in vitro cultures to study the copper tolerance mechanisms in A. maritima a micropropagation protocol has been developed. The ex vitro plants have been rooted and established in compost.

The solid-solution partitioning of heavy metals (Cu, Zn, Cd, Pb) in upland soils of England and Wales.

Ninety-eight surface soils were sampled from the uplands of England and Wales, and analysed for loss-on-ignition (LOI), and total and dissolved base cations, Al, Fe, and trace heavy metals (Cu, Zn, Cd, Pb). The samples covered wide ranges of pH (3.4-8.3) and LOI (9-98%). Soil metal contents measured by extraction with 0.43 mol l-1 HNO3 and 0.1 mol l-1 EDTA were very similar, and generally lower than values obtained by extraction with a mixture of concentrated nitric and perchloric acids. Total heavy metal concentrations in soil solution depend positively upon soil metal content and [DOC], and negatively upon pH and LOI, values of r2 ranging from 0.39 (Cu) to 0.81 (Pb). Stronger correlations (r2=0.76-0.95) were obtained by multiple regression analysis involving free metal ion (Cu2+, Zn2+, Cd2+, Pb2+) concentrations calculated with the equilibrium speciation model WHAM/Model VI. The free metal ion concentrations depend positively upon MHNO3 and negatively upon pH and LOI. The data were also analysed by using WHAM/Model VI to describe solid-solution interactions as well as solution speciation; this involved calibrating each soil sample by adjusting the content of "active" humic matter to match the observed soil pH. The calibrated model provided fair predictions of total heavy metal concentrations in soil solution, and predicted free metal ion concentrations were in reasonable agreement with the values obtained from solution-only speciation calculations.

Assessment of environmental arsenic levels in Prievidza district.

A coal-burning power station in the Nitra Valley in central Slovakia annually emitted large quantities of arsenic (up to 200 tonnes) between 1953 and 1989. Since then, pollution-control measures have reduced arsenic emissions to less than 2 tonnes a year. However, the power station was still a source of airborne arsenic pollution. As part of an EU-funded study on exposure to arsenic and cancer risk in central and Eastern Europe we carried out a study of environmental levels of arsenic in the homes and gardens of residents of the district. Garden soil samples (n=210), house dust samples (n=210) and composite house dust samples (n=109) were collected and analysed using inductively coupled plasma atomic absorption spectroscopy (ICP-AES) at Imperial College. The mean arsenic content of coal and ash in samples taken from the plant was 519 microg/g (n=19) and 863 microg/g (n=22), respectively. The geometric mean (GM) arsenic concentration of garden soils was 26 microg/g (range 8.8-139.0 microg/g), for house dust 11.6 microg/g (range 2.1-170 microg/g) and for composite house dust 9.4 microg/g (range 2.3-61.5 microg/g). The correlation between the arsenic levels in soil and in house dust was 0.3 (P<0.01), in soil and composite house dust 0.4 and house dust and composite house dust 0.4 (P<0.01 for both), i.e., were moderate. Arsenic levels in both house dust and soil decreased with distance from the power station. Overall, levels in both fell by half 5 km from the point source. Weak correlations were seen between the total urinary arsenic concentrations and arsenic concentrations in composite house dust.

Investigating urban geochemistry using Geographical Information Systems.

Geographical Information System (GIS) is an interactive digital extension of the two-dimensional paper map. Customised maps are created by the selection and aggregation of data from independent sources to assist studies in urban geochemistry. The metropolitan area of Wolverhampton, in the West Midlands, UK is used to illustrate the types of output that can be generated. These include: geographic and geological feature; geochemical data and land use. Multi-layered maps can be used to investigate spatial relationships, for example, between elevated concentrations of metals in soils and industrial land use. Such maps can also be used to assist the assessment of potential exposure of groundwater, ecosystems and humans using maps incorporating guideline values for metals in soils.

[Genetic counseling and prenatal care after medications during the first trimester]. / Genetikai tanácsadás és gondozás elsó trimeszterbeli gyógyszerszedés miatt.

Analysis of the outcome of 127 pregnancies with first trimester medication (8.4% of the total number of the patients seeking genetic advice in 1997 at the Institute of Medical Genetics in Szeged) was carried out. The gestational age at the time of the medication and genetic counselling, the indications of the treatment, the drugs, the estimated fetal risk, and results of genetic ultrasound examinations and pregnancy outcome were evaluated. The majority of pregnant woman (78%) asked for genetic counselling before the 12. gestational week. The main indications the treatment were: infections, psychiatric-neurologic (depression, anxiety, epilepsy), endocrine (diabetes, hyperthyreoidism), and cardiovascular diseases and gastrointestinal problems. The main groups of the drugs were: antibiotics, antipyretic-, antidepressive-, antidiabetic- and antihypertensive drugs. When the multiple medication was conducted by simultaneous administration of two or more drugs, a complex risk calculation was performed. The fetal risk was higher than 10% in 31 cases (24%). The ultrasound examinations performed by qualified sonographer contributed to a correct evaluation and to reliable follow-up of pregnancies. No suspicious ultrasound finding was reported in the first trimester. However, a severe fatal brain malformation was found in a second trimester pregnancy, which was terminated by the couple's request in the 18th gestational week. A complete follow-up was obtained in 70.9% (90) of the cases. Out of 64 pregnancies intended to continue to term 4 fetal malformations were found. Of them three malformations (patent ductus arteriosus, Robin sequence and a ventricular septal defect) were explored at birth or in the newborn period. The actual 6.3% of fetal malformations was higher compared to the rate expected at birth, but almost equal to the rate of congenital malformation found up to the end of the first year of age in Hungary.

[Feto-maternal transfusion following cordocentesis]. / Foetomaternalis transzfúzió cordocentesis kapcsán.

Invasive intrauterine diagnostic procedures may be followed by feto-maternal transfusion. The authors studied the feto-maternal transfusion after cordocentesis. 199 women underwent fetal umbilical cord blood sampling for fetal karyotyping in weeks 15-26. Maternal serum alpha-fetoprotein level was measured before and after the procedure. The data were statistically analysed by multiple regression analysis and the paired and unpaired Student's t-tests. Twenty percent of more maternal serum alpha-fetoprotein level increase was observed in 73 (36.7%) women. Maximum feto-maternal transfusion was 0.684 ml. The average feto-maternal transfusion was 0.045 ml. No fetal exsanguination was observed. Positive correlation was found between bleeding time after cordocentesis (p = 0.0171) and feto-maternal transfusion as well as the duration of the procedure (p = 0.0275) and feto-maternal transfusion. Negative correlation was found between the amount of fetal blood sample and feto-maternal transfusion (p = 0.0431). The puncture site also influenced feto-maternal transfusion. If the cordocentesis has been performed at the insertion of the cord the feto-maternal transfusion was less than at the free floating umbilical cord (p = 0.0293). Higher feto-maternal transfusion was seen more often after transplacental cordocentesis (p = 0.002). These data suggest that fetomaternal transfusion in the indicator of the difficulty of the procedure.

Platinum concentrations in urban road dust and soil, and in blood and urine in the United Kingdom.

Increasing Pt concentrations from vehicle catalysts have been reported from a number of countries. Analysis of Pt and Pd in soils and road dusts taken from areas of high and low traffic flows in SE England show concentrations of Pt in the range < 0.30-40.1 ng g-1 and Pd in the range < 2.1-57.9 ng g-1. Higher concentrations of Pt are associated with high traffic densities. Samples taken from streets of lower traffic flows were found to contain the lower concentrations of the ranges. Pilot studies of Pt concentrations in blood and urine using ICP-MS have been carried out. Platinum concentrations in whole blood were: precious metal workers, 780-2170, mean 1263 pmol l-1 (0.152-0.423, mean 0.246 microgram l-1); motorway maintenance workers, 645-810, mean 744 pmol l-1 (0.126-0.158, mean 0.145 microgram l-1); Imperial College staff, 590-713, mean 660 pmol l-1 (0.115-0.139, mean 0.129 microgram l-1). Platinum concentrations in urine in pmol Pt per mmol creatinine were: precious metal workers, 122-682, mean 273 [0.21-1.18, mean 0.47 microgram Pt (g creatinine)-1]; motorway maintenance workers, 13-78, mean 33.7 [0.022-0.135, mean 0.058 microgram Pt (g creatinine)-1]; Imperial College staff, 28-130, mean 65.6 [0.048-0.224, mean 0.113 microgram Pt (g creatinine)-1]. Detection limits were 0.03 microgram l-1 for both blood and urine. The possible health effects of increasing Pt in the environment are discussed. Platinum provides an excellent example of the significance of speciation in metal toxicity. Platinum allergy is confined to a small group of charged compounds that contain reactive ligand systems, the most effective of which are chloride ligand systems. Metallic Pt is considered to be biologically inert and non allergenic and since the emitted Pt is probably in the metallic or oxide form, the sensitising potential is probably very low. Platinum from road dusts, however, can be solubilised, and enter waters, sediments, soils and the food chain. There is at present no evidence for any adverse health effects from Pt in the general environment, particularly allergic reactions.

[Hemodynamic effect of plasma DNA]. / Gemodinamicheskii éffekt DNK plazmy krovi.

To reveal the hemodynamic effect of plasma DNA, the authors measured the concentrations of plasma DNA, the length of its molecular fragments, and hemodynamic resistance/Toms effect. The Toms effect was detected in all blood samples from 10 healthy donors and 39 patients without acute stroke caused by atherosclerosis of the head great arteries with and without arterial hypertension. There was a clear inverse relationships between the plasma concentrations of DNA which had only long-molecular fragments in healthy persons and the hemodynamic resistance of its blood flow samples. The patient blood plasma had significant increased DNA concentrations but their molecular fragments were long and short. Inverse relationships between the plasma DNA concentration and the hemodynamic resistance of the patients' blood flow samples had a less correlation coefficient due to the high proportion of short DNA molecular fragments. The Toms effect was shown in the DNA solution prepared only from human funic blood where the DNA molecular fragments were long. The Toms effect was absent in the solutions prepared from the commercial cattle or salmon sperm DNA which contained shorter DNA molecular fragments. It is concluded that plasma DNA has a hemodynamic effect and the origin of long-molecular fragments of DNA which is typical for healthy young persons and short DNA molecular fragments that additionally appear in patients with vascular disorders is different.

Urinary arsenic species in Devon and Cornwall residents, UK. A pilot study.

First void urine samples were collected from 24 residents in an area of past intense mining and smelting activity of arsenical ores. Seven samples were also taken from a control village. The arsenic species in the urine were separated and quantified with an HPLC-ICP-MS system equipped with a hydraulic high-pressure nebulizer. The detection limit for arsenic in urine using this system is 0.05 microgram dm-3. Creatinine was also determined for all samples to remove the influence of urine density and all results were expressed in microgram As g-1 creatinine. The results showed elevated levels of both organic and inorganic arsenic compounds in the 'exposed' population's urine when compared with those of the control group. The total As concentrations (less arsenobetaine) in the 'exposed' population were in the range 2.7-58.9 micrograms g-1 creatinine (mean 13.4, median 9.2 micrograms g-1) compared with the control group data range 2.5-5.3 micrograms g-1 (mean 4.2, median 4.7 micrograms g-1).

[150 years from the birth of Endre Hogyes, promotor of Hungarian medicine]. / Endre Hogyes - Unkarin lääketieteen kehittäjän syntymästä 150 vuotta.

Endre Hogyes, one of the most prominent and internationally known leaders in the field of medical research, a specialist on the treatment of rabies, was born one hundred and fifty years ago in Hungary. E. Hogyes started his medical career and research in 1870. In 1889 he became vice-president of the Royal Hungarian society of Natural Sciences and was elected as member of the Hungarian Academy of Sciences (MTA) and member of the National Council of Public Health. The scientific career of E Hogyes was throughout closely linked to the physiological sciences. He contributed significantly in different fields of the physiological sciences. His most important scientific publications in this field deal with renal physiology, respiratory mechanics, cerebellar function and associated eye movements. Endre Hogyes was the first to organize Hungarian physiologists into a community. The "Special Physiological Conferences" were initiated within the Hungarian Royal Society of Natural Sciences in 1891. As a proof of appreciation, Hungarian physiologists and other medical professionals have proclaimed the year 1997 as a memorial year of Dr. Endre Hogyes.

Physiology in the oeuvre of a prominent Hungarian medical scientist--Endre H"ogyes.

Endre Hógyes, one of the most prominent and internationally-renown leaders in the field of medical research, especially the treatment of rabies, was born one hundred and fifty years ago in Hungary. E. Hógyes had started his medical and research carrier in 1870. In 1889 he had become vice-president of the Royal Hungarian Society of Natural Sciences and was elected as a member of the Hungarian Academy of Sciences (MTA) and that member of the National Council of Public Health. Scientific carrier of E. Hógyes has always been closely linked to physiological sciences. E Hógyes made a significant contribution to different areas of physiological sciences; his most important scientific publications in this field deal with renal physiology, respitary mechanics, cerebellar function, and associated eye movement. Endre Hógyes was the first to organize Hungarian physiologists into a community. The "Special Physiological Conferences" were initiated within the Hungarian Royal Society of Natural Sciences in 1891. As a token of appretiation, Hungarian physiologists and other medical professionals have announced the year of 1997 as a memorial year of Dr. Endre Hógyes.

Changes in lead concentrations in the home environment in Birmingham, England over the period 1984-1996.

Data for lead concentrations reported in Birmingham prior to 1984 were reviewed and thought to be not strictly comparable in these surveys due to various sampling and analysis methodologies. A survey was implemented to compare the concentrations of lead for 1984/1985 with those of 85 houses re-sampled within the city in 1996. It is shown that lead concentrations and loading of dusts in and around the houses have fallen significantly over the last 11 years. However, lead concentrations in soils have only slightly decreased over the same period. The US EPA IEUBK model for exposure of children to lead is validated, updated and applied to predict the blood lead level of young children. It is predicted that the blood lead concentrations of 2-year-old children have been reduced considerably over the period. The fall in lead concentrations is thought to be the consequence of the reduction policies for lead emissions in the UK since the 1980s. The result of this study provides a valuable example of the benefits of the reduction policies for lead which are of equal importance in developing countries with rapid economic growth.