SEGH Articles

Assessment of the environmental conditions of the Calore river basin (south Italy): a stream sediment approach

23 October 2015
Daniela Zuzolo from the University of Sannio won the Hemphill prize for best student presentation at SEGH 2015 in Bratislava. She provides a follow-up on her presentation.

 

 

In 2014 we carried out a study on the stream sediments of the Calore river (a tributary of the Volturno, the biggest south-Italian river) to assess the environmental conditions of a basin that covers 3058 Km2 (Fig.1) of the Campania region and that, until now, has been only marginally studied from this point of view.

 

Our study showed that, despite evidence from concentrations of many elements for enrichment over natural background values, the spatial distribution of major and trace elements in Calore river basin is determined mostly by geogenic factors. Figure 2 shows the main lithological features of the study area, while Figure 3 shows the spatial distribution of elemental association factor scores.

 

 

 

 

The south-western area of the basin highlighted an enrichment of many elements potentially harmful for human health and other living organisms (Al, Fe, K, Na, As, Cd, La, Pb, Th, Tl, U); but these anomalies are due to the presence of pyroclastics and alkaline volcanic lithologies.

Even where sedimentary lithologies occur (in northern area), many harmful elements (Co, Cr, Mn, Ni) have shown high concentration levels due to a natural origin.

 

 

 

 

On the other hand, a strong heavy metal contamination (Pb, Zn, Cu, Sb, Ag, Au, Hg), due to an anthropic contribution, is highlighted in many areas characterised by the presence of road junctions, urban settlements and industrial areas. Figure 4 highlights the enrichment factors of these elements: 3 - 4 time higher than the background values. The south-western area of the basin is characterised by a moderate/high degree of contamination (Fig.5), just where the two busiest roads of the area run and the highest concentration of industries occurs.

 

We assessed the distribution of the potentially harmful elements (PHE) and the related interpretations using geochemical indexes, chemometric approach and mapping of the other relevant information, all linked to PHE distribution.

First of all, 562 stream sediment samples were collected, air-dried, sieved to < 100 mesh fraction and analyzed for 37 elements after an aqua regia extraction by a combination of ICP-AES and ICP-MS.

Univariate and multivariate statistical analyses of data were performed to show the single element distribution and the distribution of elemental association factor scores resulting from R-mode factor analyses, in order to interpret the hypothetical origin of elements’ distribution (natural, anthropogenic or mixed).

The degree of contamination of the area was evaluated through analysing the Contamination Factor index and the production of a Contamination Degree map.

This approach proved successful as it achieved meaningful results and interpretations of complex datasets. It represents a useful tool to evaluate the hypothetical origin of geochemical anomalies of stream sediments; it also allows a quantitative assessment of the metal pollution threat to ecosystem and human health.

by Daniela Zuzoloa*, Domenico Cicchellaa, Lucia Giaccioa, Ilaria Guagliardib, Libera Espositoa

a - Department of Science and Technology, University of Sannio, via dei Mulini 59/A, 82100 - Benevento, Italy

b - Department of Biology, Ecology and Earth Sciences, University of Calabria, Via Ponte Bucci 4, cubo 15B, I-87036 Arcavacata di Rende (CS), Italy

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

  • Fate and partitioning of heavy metals in soils from landfill sites in Cape Town, South Africa: a health risk approach to data interpretation 2019-06-14

    Abstract

    The fate and persistence of trace metals in soils and sludge from landfill sites are crucial in determining the hazard posed by landfill, techniques for their restoration and potential reuse purposes of landfill sites after closure and restoration. A modified European Community Bureau of Reference’s (BCR) sequential extraction procedure was applied for partitioning and evaluating the mobility and persistence of trace metals (As, Cd, Cr, Cu, Ni, Pb, Sb, Se, Zn) in soils from three landfill sites and sludge sample from Cape Town, South Africa. Inductively coupled plasma optical emission spectroscopy was used to analyze BCR extracts. The mobility sequence based on the BCR mobile fraction showed that Cu (74–87%), Pb (65–80%), Zn (59–82%) and Cd (55–66%) constituted the mobile metals in the soils from the three sites. The mobility of Cu, Zn and Ni (> 95%) was particularly high in the sludge sample, which showed significant enrichment compared to the soil samples. Geo-accumulation index (Igeo) and risk assessment code were used to further assess the environmental risk of the metals in the soils. Exposure to the soils and sludge did not pose any non-cancer risks to adult and children as the hazard quotient and hazard index values were all below the safe level of 1. The cancer risks from Cd, Cr and Ni require that remedial action be considered during closure and restoration of the landfill sites.

  • An investigation into the use of < 38 µm fraction as a proxy for < 10 µm road dust particles 2019-06-13

    Abstract

    It is well documented that a large portion of urban particulate matters is derived from road dust. Isolating particles of RD which are small enough to be inhaled, however, is a difficult process. In this study, it is shown for the first time that the < 38 µm fraction of road dust particles can be used as a proxy for road dust particles < 10 µm in bioaccessibility studies. This study probed similarities between the < 10 and < 38µm fractions of urban road dust to show that the larger of the two can be used for analysis for which larger sample masses are required, as is the case with in vitro analysis. Road dust, initially segregated to size < 38 µm using sieves, was again size segregated to < 10 µm using water deposition. Both the original < 38 µm and the separated < 10 µm fractions were then subject to single particle analysis by SEM–EDX and bulk analysis by ICP-OES for its elemental composition. Dissolution tests in artificial lysosomal fluid, representative of lung fluid, were carried out on both samples to determine % bioaccessibility of selected potentially harmful elements and thus probe similarities/differences in in vitro behaviour between the two fractions. The separation technique achieved 94.3% of particles < 10 µm in terms of number of particles (the original sample contained 90.4% as determined by SEM–EDX). Acid-soluble metal concentration results indicated differences between the samples. However, when manipulated to negate the input of Si, SEM–EDX data showed general similarities in metal concentrations. Dissolution testing results indicated similar behaviour between the two samples in a simulated biological fluid.

  • Degradation of petroleum hydrocarbons in unsaturated soil and effects on subsequent biodegradation by potassium permanganate 2019-06-13

    Abstract

    To date, the oxidation of petroleum hydrocarbons using permanganate has been investigated rarely. Only a few studies on the remediation of unsaturated soil using permanganate can be found in the literature. This is, to the best of our knowledge, the first study conducted using permanganate pretreatment to degrade petroleum hydrocarbons in unsaturated soil in combination with subsequent bioaugmentation. The pretreatment of diesel-contaminated unsaturated soil with 0.5-pore-volume (5%) potassium permanganate (PP) by solution pouring and foam spraying (with a surfactant) achieved the total petroleum hydrocarbon (TPH) removal efficiencies of 37% and 72.1%, respectively. The PP foam, when coupled with bioaugmentation foam, further degraded the TPH to a final concentration of 438 mg/kg (92.1% total reduction). The experiment was conducted without soil mixing or disturbance. The relatively high TPH removal efficiency achieved by the PP–bioaugmentation serial foam application may be attributed to an increase in soil pH caused by the PP and effective infiltration of the remediation agent by foaming. The applied PP foam increased the pH of the acidic soil, thus enhancing microbial activity. The first-order biodegradation rate after PP oxidation was calculated to be 0.068 d−1. Furthermore, 94% of the group of relatively persistent hydrocarbons (C18–C22) was removed by PP–bioaugmentation, as verified by chromatogram peaks. Some physicochemical parameters related to contaminant removal efficiency were also evaluated. The results reveal that PP can degrade soil TPH and significantly enhance the biodegradation rate in unsaturated diesel-contaminated soil when combined with bioaugmentation foam.