SEGH Articles

SEGH Member participated in the Antarctic Circumpolar Expedition

02 July 2017
Francois De Vleeschouwer, researcher at EcoLab, (CNRS, Toulouse France) and SEGH secretary, had the opportunity to embark onboard the RV Akademik Treshnikov to participate in the ACE Expedition


François De Vleeschouwer, researcher at EcoLab, (CNRS, Toulouse France) and SEGH secretary, had the opportunity to embark onboard the RV Akademik Treshnikov to participate in the ACE Expedition. From December 2016 to March 2017, scientific teams from all over the world joined into an unprecedented expedition around Antarctica. From biology to climatology to oceanography, researchers from 22 selected projects worked on a number of interrelated fields revolving around Antarctica.

 

François De Vleeschouwer is involved in a British Antarctic Survey-supervised project dealing with « Measuring the changes in the ocean’s capacity to absorb CO2 ». Concentrations of CO2 in the atmosphere have increased since 1750 AD as a result of human activity. This is linked to warming of the atmosphere and oceans, changes in climate, recession of ice sheets and sea level rise. More than one quarter of this CO2 is absorbed by the oceans; the Southern Ocean accounting for 43%. The capacity of the Southern Ocean to absorb CO2 has recently been limited (according to some models) by an increase in the strength of the Southern Hemisphere Westerly Winds (SHW), which draw CO2 saturated waters back to the surface. This will potentially drive up atmospheric greenhouse gases and accelerate rates of global warming.Reconstructing past changes in the SHW and their impact on the oceanic CO2 sink is therefore a major priority for palaeoclimate science.

 

François De Vleeschouwer participated to the leg 2 of the ACE navigation from Hobart, Tasmania to Punta Arenas, Chile. After an unfortunate storm that obliged the expedition to cancel the sampling at Macquarie Island, the boat navigated throuhgh Antarctic waters to then cross the Drake’s Passage. F. De Vleeschouwer sampled soils, mosses and peatlands on various islands from the Antarctic (Scott, Maher, Lauft, Siple) and sub-Antarctic (Diego Ramirez Archipelago).

 

The main objective of this project is to determine the Holocene (last 12000 yrs) changes in the strength of the SHW over the Southern Ocean by generating records of wind-driven aerosols and other proxies in sediment records from lakes and bogs on the west coasts of sub-Antarctic islands and, These data will be further used in global climate models to test if past changes in the SHW explain past variations in atmospheric CO2.

Further information can be found on : http://spi-ace-expedition.ch/

 

Francois de Vleeschouwer, CNRS, Toulouse, France

Keep up to date

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

  • Arsenic exposure and perception of health risk due to groundwater contamination in Majuli (river island), Assam, India 2019-07-19

    Abstract

    Island populations are rarely studied for risk of arsenic (As) poisoning. As poisoning, multimetal contamination and people’s perceptions of health risks were assessed on India’s Majuli Island, the largest inhabited river island in the world. This holistic approach illustrated the association of groundwater contamination status with consequent health risk by measuring levels of inorganic arsenic (iAs) in groundwater, borehole sediment and biological samples (hair, nails and urine). Piper and Gibbs’s plots discerned the underlying hydrogeochemical processes in the aquifer. Demographic data and qualitative factors were evaluated to assess the risks and uncertainties of exposure. The results exhibited significant enrichment of groundwater with As, Mn and Fe along with significant body burden. Maximum Hazard Index values indicated severe non-carcinogenic health impacts as well as a significantly elevated risk of cancer for both adults and children. Most (99%) of the locally affected population did not know about the adverse health impacts of metal contamination, and only 15% understood bodily ailments and health issues. Various aspects of the island environment were used to elucidate the status of contamination and future risk of disease. A projection showed adverse health outcomes rising significantly, especially among the young population of Majuli, due to overexposure to not only As but also Ba, Mn and Fe.

  • The contents of the potentially harmful elements in the arable soils of southern Poland, with the assessment of ecological and health risks: a case study 2019-07-19

    Abstract

    Agricultural soil samples were collected from the areas where edible plants had been cultivated in southern Poland. The PHE content decreased in proportion to the median value specified in brackets (mg/kg d.m.) as follows: Zn (192) > Pb (47.1) > Cr (19.6) > Cu (18.8) > Ni (9.91) > As (5.73) > Co (4.63) > Sb (0.85) > Tl (0.04) > Cd (0.03) > Hg (0.001) > Se (< LOQ). No PHE concentrations exceeded the permissible levels defined in the Polish law. The PHE solubility (extracted with CaCl2) in the total concentration ranged in the following order: Fe (3.3%) > Cd (2.50%) > Ni (0.75%) > Zn (0.48%) > Cu (0.19%) > Pb (0.10%) > Cr (0.03%). The soil contamination indices revealed moderate contamination with Zn, ranging from uncontaminated to moderately contaminated with Pb, and, practically, no contamination with other PHEs was identified. The ecological risk indices revealed that soils ranged from uncontaminated to slightly contaminated with Zn, Pb, As, Cu, and Ni. The PCA indicated natural sources of origin of Co, Cu, Hg, Sb, Zn, Cr, and Pb, as well as anthropogenic sources of origin of Cd, Ni, As, and Tl. The human health risk assessment (HHRA) for adults and children decreased in the following order of exposure pathways: ingestion > dermal contact > inhalation of soil particles. The total carcinogenic risk values for both adults and children were at the acceptable level under residential (1.62E−05 and 6.39E−05) and recreational scenario (5.41E−06 and 2.46E−05), respectively, as well as for adults in agricultural scenario (1.45E−05). The total non-carcinogenic risk values for both adults and children under residential scenario (1.63E−01 and 4.55E−01, respectively), under recreational scenario (2.88E−01 and 6.69E−01, respectively) and for adults (1.03E−01) under agricultural scenario indicated that adverse health effects were not likely to be observed. Investigated soils were fully suitable for edible plant cultivation.

  • Using human hair and nails as biomarkers to assess exposure of potentially harmful elements to populations living near mine waste dumps 2019-07-17

    Abstract

    Potentially harmful elements (PHEs) manganese (Mn), cobalt (Co), copper (Cu), lead (Pb), nickel (Ni) and zinc (Zn) were measured in human hair/nails, staple crops and drinking water to ascertain the level of exposure to dust transference via wind and rain erosion for members of the Mugala community living near a mine waste dump in the Zambian Copperbelt. The mean PHE concentrations of hair in decreasing order were Zn (137 ± 21 mg/kg), Cu (38 ± 7 mg/kg), Mn (16 ± 2 mg/kg), Pb (4.3 ± 1.9 mg/kg), Ni (1.3 ± 0.2 mg/kg) and Cr (1.2 ± 0.2 mg/kg), Co (0.9 ± 0.2 mg/kg) and Cd (0.30 ± 0.02 mg/kg). Whilst for toenails the decreasing order of mean concentrations was Zn (172 ± 27 mg/kg), Cu (30 ± 5 mg/kg), Mn (12 ± 2 mg/kg), Pb (4.8 ± 0.5 mg/kg), Ni (1.7 ± 0.14 mg/kg) and Co (1.0 ± 0.02 mg/kg), Cr (0.6 ± 0.1 mg/kg) and Cd (0.1 ± 0.002 mg/kg). The concentration of these potentially harmful elements (PHEs) varied greatly among different age groups. The results showed that Mn, Co, Pb, Cd and Zn were above the interval values (Biolab in Nutritional and environmental medicine, Hair Mineral Analysis, London, 2012) at 0.2–2.0 mg/kg for Mn, 0.01–0.20 mg/kg for Co, < 2.00 mg/kg for Pb, < 0.10 mg/kg for Cd and 0.2–2.00 mg/kg for Zn, whilst Ni, Cu and Cr concentrations were within the normal range concentrations of < 1.40 mg/kg, 10–100 mg/kg and 0.1–1.5 mg/kg, respectively. Dietary intake of PHEs was assessed from the ingestion of vegetables grown in Mugala village, with estimated PHE intakes expressed on a daily basis calculated for Mn (255), Pb (48), Ni (149) and Cd (33) µg/kg bw/day. For these metals, DI via vegetables was above the proposed limits of the provisional tolerable daily intakes (PTDIs) (WHO in Evaluation of certain food additive and contaminants, Seventy-third report of the Joint FAO/WHO Expert Committee on Food Additives, 2011) for Mn at 70 µg/kg bw/day, Pb at 3 µg/kg bw/day, Ni and Cd 5 µg/kg bw/day and 1 µg/kg bw/day, respectively. The rest of the PHEs listed were within the PTDIs limits. Therefore, Mugala inhabitants are at imminent health risk due to lead, nickel and cadmium ingestion of vegetables and drinking water at this location.