SEGH Articles

SEGH 2015: a PhD researchers perspective

15 October 2015
Dan Middleton, a PhD student from the University of Manchester, based at the Centre for Environmental Geochemistry at the British Geological Survey, shares his account of the conference proceedings.


June saw the 31st International Conference of the Society for Environmental Geochemistry and hosted by the State Geological Institute of Dionýz Štúr (SGIDŠ) in Bratislava, Slovak Republic. Dan Middleton, a BUFI funded PhD student from the University of Manchester, based at the Centre for Environmental Geochemistry at the British Geological Survey, shares his account of the conference proceedings.

The coming together of our scientific community to disseminate and share recent and ongoing research findings is, in my opinion, a vital aspect of the development process of our rapidly growing field. Our community in particular is a relatively tight-knit group compared to the core scientific disciplines and one which crosses many boundaries, making networking opportunities such as SEGH 2015 essential for sharing expertise and gaining contacts across broad skill sets. A small community it may be, but nevertheless, more than 80 delegates from 24 countries covering 4 continents descended on the Holiday Inn, Bratislava to fuel a fruitful showcase of projects covering  themes of analytical chemistry, geochemistry, environmental epidemiology and medical geology to name but a few.

 

Of particular interest to me were the health related topics, as they bridge the gap between measurements of inorganic and organic substances in our environment and how they affect our well-being, both detrimentally and beneficially. This matter was addressed early on by Prof. Stanislav Rapant, hosting the event, in his opening presentation. Using a geochemical baseline survey spanning the whole of the Slovak Republic, Prof Rapant and colleagues from SGIDŠ were able to link concentrations of calcium (Ca) and magnesium (Mg) in drinking water to health statistics of cardiovascular disease (CVD), finding an inverse correlation between exposure and outcome. This research highlighted the first of two take-home messages for me personally – drinking water chemistry is often studied in the light of excess concentrations of chemical elements (I myself gave a presentation on arsenic (As) in UK private water supplies) but of equal importance to human health is ensuring a sufficient supply of the elements that underpin key physiological mechanisms, a point reinforced by Dr Alex Stewart in his talk on the negative health implications of iodine (I) deficiency.

 

BGS’s very own Dr Mark Cave was in attendance and presented a keynote lecture on findings from a recent project examining the links between London’s soil geochemistry and health related deprivation indices. Mark found that the while unemployment showed the strongest link with detrimental health outcomes, tin (Sn) in soils showed a curious relationship out of the elements studied. This relationship requires further investigation as the causal link between the two variables in not established, however the study demonstrates the power of computer based statistical modelling, in this case the random forest method, in unlocking the secrets of large multivariate datasets.

Another standout talk was that of Dr Munir Zia from the Fauji Fertilizer Company in Pakistan, who presented collaborate research with BGS on potentially harmful elements and dietary minerals in vegetable crops grown in wastewater irrigated soils. Dr Zia used a multitude of techniques to measure both the total and bioaccessible concentrations of analytes in soil and vegetable samples as well as estimating daily intake rates based on literature derived figures and comparing with existing guidance values. For me this highlighted the importance of using an interdisciplinary approach to research problems such as these and addressing the question from a number of angles. This allows us to not only quantify the chemical composition of the media we study, but begin to explore the potential impacts that these compositions may or may not have on our health.

This leads me to the second take-home message of the conference. As geochemists, analytical chemists and environmental scientists, we have an abundance of instrumental techniques at our disposal that enable us to generate quantitative chemical data across a diverse range of samples. What many of us lack in our armoury is the medical and epidemiological expertise to compliment such findings. Environmental Geochemistry and Health is an ever important field and as researchers we need to make sure that both sides of the discipline are maintained. This will be achieved through the coming together of those from both the physical and medical sciences and in particular through the continued engagement of the latter. Furthermore, the personal development of skills outside our respective backgrounds will also aid in forming an adhesive bond between the two factions and promote research that gets closer to answering the question of how our environment impacts our health.

Overall, another worthwhile and insightful meeting that demonstrated the ongoing efforts of our community to engage in diverse research problems using techniques, both analytically and statistically, that are cutting-edge and at the forefront of our field. A big thank you to organisers and delegates alike for making SEGH 2015 a memorable event as we look towards Brussels 2016.  

Daniel Middleton, PhD Researcher

University of Manchester and British Geological Survey

Keep up to date

SEGH Events

Submit Content

Members can keep in touch with their colleagues through short news and events articles of interest to the SEGH community.

Science in the News

Latest on-line papers from the SEGH journal: Environmental Geochemistry and Health

  • Assessment of the toxicity of silicon nanooxide in relation to various components of the agroecosystem under the conditions of the model experiment 2018-08-18

    Abstract

    Investigation of SiO2 nanoparticles (NPs) effect on Eisenia fetida showed no toxic effect of the metal at a concentration of 250, 500 and 1000 mg per kg of soil, but conversely, a biomass increase from 23.5 to 29.5% (at the protein level decrease from 60 to 80%). The reaction of the earthworm organism fermentative system was expressed in the decrease in the level of superoxide dismutase (SOD) on the 14th day and in the increase in its activity to 27% on the 28th day. The catalase level (CAT) showed low activity at average element concentrations and increase by 39.4% at a dose of 1000 mg/kg. Depression of malonic dialdehyde (MDA) was established at average concentrations of 11.2% and level increase up to 9.1% at a dose of 1000 mg/kg with the prolongation of the effect up to 87.5% after 28-day exposure. The change in the microbiocenosis of the earthworm intestine was manifested by a decrease in the number of ammonifiers (by 42.01–78.9%), as well as in the number of amylolytic microorganisms (by 31.7–65.8%). When the dose of SiO2 NPs increased from 100 to 1000 mg/kg, the number of Azotobacter increased (by 8.2–22.2%), while the number of cellulose-destroying microorganisms decreased to 71.4% at a maximum dose of 1000 mg/kg. The effect of SiO2 NPs on Triticum aestivum L. was noted in the form of a slight suppression of seed germination (no more than 25%), an increase in the length of roots and aerial organs which generally resulted in an increase in plant biomass. Assessing the soil microorganisms’ complex during introduction of metal into the germination medium of Triticum aestivum L., there was noted a decrease in the ammonifiers number (by 4.7–67.6%) with a maximum value at a dose of 1000 mg/kg. The number of microorganisms using mineral nitrogen decreased by 29.5–69.5% with a simultaneous increase in the number at a dose of 50 mg/kg (+ 20%). Depending on NP dose, there was an inhibition of the microscopic fungi development by 18.1–72.7% and an increase in the number of cellulose-destroying microorganisms. For all variants of the experiment, the activity of soil enzymes of the hydrolase and oxidoreductase classes was decreased.

  • Seasonal characteristics of chemical compositions and sources identification of PM 2.5 in Zhuhai, China 2018-08-16

    Abstract

    Fine particulate matter is associated with adverse health effects, but exactly which characteristics of PM2.5 are responsible for this is still widely debated. We evaluated seasonal dynamics of the composition and chemical characteristics of PM2.5 in Zhuhai, China. PM2.5 characteristics at five selected sites within Zhuhai city were analyzed. Sampling began on January 10, 2015, and was conducted for 1 year. The ambient mass concentration, carbon content (organic and elemental carbon, OC and EC), level of inorganic ions, and major chemical composition of PM2.5 were also determined. Average concentrations of PM2.5 were lower than the National Ambient Air Quality Standard (NAAQS) 24-h average of 65 μg/m3. The daily PM2.5 concentration in Zhuhai city exhibited clear seasonal dynamics, with higher daily PM2.5 concentrations in autumn and winter than in spring and summer. Carbon species (OC and EC) and water-soluble ions were the primary components of the PM2.5 fraction of particles. Apart from OC and EC, chemical species in PM2.5 were mainly composed of NH4+ and SO42−. There was a marked difference between the summer and winter periods: the concentrations of OC and EC in winter were roughly 3.4 and 4.0 times than those in summer, while NH4+, SO42−, NO3, and Na+ were 3.2, 4.5, 28.0, and 5.7 times higher in winter than those in summer, respectively. The results of chemical analysis were consistent with three sources dominating PM2.5: coal combustion, biomass burning, and vehicle exhaust; road dust and construction; and from reaction of HCl and HNO3 with NH3 to form NH4Cl and NH4NO3. However, additional work is needed to improve the mass balance and to obtain the source profiles necessary to use these data for source apportionment.

  • Estimates of potential childhood lead exposure from contaminated soil using the USEPA IEUBK model in Melbourne, Australia 2018-08-14

    Abstract

    Soils in inner city areas internationally and in Australia have been contaminated with lead (Pb) primarily from past emissions of Pb in petrol, deteriorating exterior Pb-based paints and from industry. Children can be exposed to Pb in soil dust through ingestion and inhalation leading to elevated blood lead levels (BLLs). Currently, the contribution of soil Pb to the spatial distribution of children’s BLLs is unknown in the Melbourne metropolitan area. In this study, children’s potential BLLs were estimated from surface soil (0–2 cm) samples collected at 250 locations across the Melbourne metropolitan area using the United States Environmental Protection Agency (USEPA) Integrated Exposure Uptake Biokinetic (IEUBK) model. A dataset of 250 surface soil Pb concentrations indicate that soil Pb concentrations are highly variable but are generally elevated in the central and western portions of the Melbourne metropolitan area. The mean, median and geometric soil Pb concentrations were 193, 110 and 108 mg/kg, respectively. Approximately 20 and 4% of the soil samples exceeded the Australian HIL-A residential and HIL-C recreational soil Pb guidelines of 300 and 600 mg/kg, respectively. The IEUBK model predicted a geometric mean BLL of 2.5 ± 2.1 µg/dL (range: 1.3–22.5 µg/dL) in a hypothetical 24-month-old child with BLLs exceeding 5 and 10 µg/dL at 11.6 and 0.8% of the sampling locations, respectively. This study suggests children’s exposure to Pb contaminated surface soil could potentially be associated with low-level BLLs in some locations in the Melbourne metropolitan area.