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Selected technology-critical elements as indicators of anthropogenic groundwater contamination
2021
Amiel, Nitai | Dror, Ishai | Zurieli, Arik | Livshitz, Yakov | Reshef, Guy | Berkowitz, Brian
Groundwater contamination originating from anthropogenic industrial activities is a global concern, adversely impacting health of living organisms and affecting natural ecosystems. Monitoring contamination in a complex groundwater system is often limited by sparse data and poor hydrogeological delineation, so that numerous indicators (organic, inorganic, isotopic) are frequently used simultaneously to reduce uncertainty. We suggest that selected Technology-Critical Elements (TCEs), which are usually found in very low concentrations in the groundwater environment, might serve as contamination indicators that can be monitored through aquifer systems. Here, we demonstrate the use of selected TCEs (in particular, Y, Rh, Tl, Ga, and Ge) as indicators for monitoring anthropogenic groundwater contamination in two different groundwater systems, near the Dead Sea, Israel. Using these TCEs, we show that the sources of local groundwater contamination are phosphogypsum ponds located adjacent to fertilizer plants in two industrial areas. In addition, we monitored the spatial distribution of the contaminant plume to determine the extent of well and spring contamination in the region. Results show significant contamination of the groundwater beneath both fertilizer plants, leading to contamination of a series of wells and two natural springs. The water in these springs contains elevated concentrations of toxic metals; U and Tl levels, among others, are above the maximum concentration limits for drinking water.
اظهر المزيد [+] اقل [-]Maternal exposure to alkali, alkali earth, transition and other metals: Concentrations and predictors of exposure
2015
Hinwood, A.L. | Stasinska, A. | Callan, A.C. | Heyworth, J. | Ramalingam, M. | Boyce, M. | McCafferty, P. | Odland, J.Ø
Most studies of metals exposure focus on the heavy metals. There are many other metals (the transition, alkali and alkaline earth metals in particular) in common use in electronics, defense industries, emitted via combustion and which are naturally present in the environment, that have received limited attention in terms of human exposure. We analysed samples of whole blood (172), urine (173) and drinking water (172) for antimony, beryllium, bismuth, cesium, gallium, rubidium, silver, strontium, thallium, thorium and vanadium using ICPMS. In general most metals concentrations were low and below the analytical limit of detection with some high concentrations observed. Few factors examined in regression models were shown to influence biological metals concentrations and explained little of the variation. Further study is required to establish the source of metals exposures at the high end of the ranges of concentrations measured and the potential for any adverse health impacts in children.
اظهر المزيد [+] اقل [-]Bourgeoning impact of the technology critical elements in the marine environment
2020
Bu-Olayan, A.H. | Thomas, B.V.
Contamination of the Technology Critical Elements (TCE) through e-wastes and beach plastic wastes are some of the attributes to the recent rise in marine pollution. A generalized study of pollutants in the marine waters showed no evidence of the effect of TCE. However, an in-depth study revealed the mean TCE concentrations in the sequence of gallium (Ga) > thallium (Tl) > niobium (Nb) > tellurium (Te) > tantalum (Ta) > germanium (Ge) > indium (In) in wastewater (0.38 ng.L⁻¹) >sediment (0.3 ng g⁻¹) e-wastes (0.29 ng g⁻¹) > coastal water (0.26 ng.L⁻¹) > plastic wastes (0.133 ng g⁻¹) >fish (0.13 ng g⁻¹). The mean site-wise analysis of all the samples showed high TCE during winter than in the summer seasons as well, in the sequence of Site-II>Site-I>Site-V>Site-IV>Site-III. The mean distribution coefficient (Kd) of TCE was high in the summer (1.95) than during the winter (1.60) seasons but, the reverse seasonal effects were observed with the bioavailability (%BA) and geo-accumulation index (Igₑₒ). This index quantified TCE in e-wastes and plastic materials. Furthermore, these indicators labeled TCE as one among the sources for ‘Fish Kill,’ a futuristic threat to seafood consumers and a biomonitoring tool to marine pollution.
اظهر المزيد [+] اقل [-]A novel bioassay using the barnacle Amphibalanus amphitrite to evaluate chronic effects of aluminium, gallium and molybdenum in tropical marine receiving environments
2016
van Dam, Joost W. | Trenfield, Melanie A. | Harries, Simon J. | Streten, Claire | Harford, Andrew J. | Parry, David | van Dam, Rick A.
A need exists for appropriate tools to evaluate risk and monitor potential effects of contaminants in tropical marine environments, as currently impact assessments are conducted by non-representative approaches. Here, a novel bioassay is presented that allows for the estimation of the chronic toxicity of contaminants in receiving tropical marine environments. The bioassay is conducted using planktonic larvae of the barnacle Amphibalanus amphitrite and is targeted at generating environmentally relevant, chronic toxicity data for water quality guideline derivation or compliance testing. The developmental endpoint demonstrated a consistently high control performance, validated through the use of copper as a reference toxicant. In addition, the biological effects of aluminium, gallium and molybdenum were assessed. The endpoint expressed high sensitivity to copper and moderate sensitivity to aluminium, whereas gallium and molybdenum exhibited no discernible effects, even at high concentrations, providing valuable information on the toxicity of these elements in tropical marine waters.
اظهر المزيد [+] اقل [-]Effects of alumina refinery wastewater and signature metal constituents at the upper thermal tolerance of: 1. The tropical diatom Nitzschia closterium
2011
Harford, A.J. | Hogan, A.C. | Tsang, J.J. | Parry, D.L. | Negri, A.P. | Adams, M.S. | Stauber, J.L. | van Dam, R.A.
Ecotoxicological studies, using the tropical marine diatom, Nitzschia closterium (72-h growth rate), were undertaken to assess potential issues relating to the discharge from an alumina refinery in northern Australia. The studies assessed: (i) the species’ upper thermal tolerance; (ii) the effects of three signature metals, aluminium (Al), vanadium (V) and gallium (Ga) (at 32°C); and (iii) the effects of wastewater (at 27 and 32°C). The critical thermal maximum and median inhibition temperature for N. closterium were 32.7°C and 33.1°C, respectively. Single metal toxicity tests found that N. closterium was more sensitive to Al compared to Ga and V, with IC₅₀s (95% confidence limits) of 190 (140–280), 19,640 (11,600–25,200) and 42,000 (32,770–56,000)μgL⁻¹, respectively. The undiluted wastewater samples were of low toxicity to N. closterium (IC₅₀s>100% wastewater). Environmental chemistry data suggested that the key metals and discharge are a very low risk to this species.
اظهر المزيد [+] اقل [-]Hydrogenic Heavy Metals Contamination of Fluvisols in the Middle Cis-Urals Region, Russia
2014
Vodyanitskii, Yu. N. | Savichev, A. T.
In 1999, the Perm region ranked eighth among Russian regions in terms of technogenic load per unit of area (4.4 t/km²). The situation in the city of Perm is especially unfavorable in ecological terms due to aerial contamination and hydrogenic contamination, because of industrial wastes entering the small rivers that are tributaries of the Kama river. It was revealed that fluvisols of the city of Perm are contaminated by heavy metals of hydrogenic origin because of the unpurified sewage water entering them. The fluvisols of the city of Perm are contaminated by heavy metals of hydrogenic origin because of the unpurified sewage water entering them.Content of HMs in fine earth showed the deficit and excess compared with European Soil Clarke and Local Background. In relation to European Soil Clarkes elements can be divided into three groups: (1) scarce elements forming negative geochemical anomaly, (2) "normal" elements, which does not differ significantly from Clarke, (3) excess elements forming positive geochemical anomaly. Scarce elements include rubidium and arsenic. “Normal” elements are yttrium, gallium, zirconium and lead. Excess elements are nickel, copper, zinc, strontium and chromium. In the fluvisols, the Fe-rohrensteins are formed. Some elements are concentrated in the Fe-rohrensteins, and some others are not concentrated in them or are found in low concentrations. In Fe-rohrensteins the highly active group comprises As, Zn, Ni, Cu, Cr, and Pb; the moderately active one is represented by Sr, Nb, Ga, and Y; and the inert group contains Zr and Rb. The contents of some chemical elements in Fe-rohrensteins are much greater than those in the fine earth. The Pb and Zn contents in Fe-rohrensteins of the soil of small rivers basin are 440 and 890 mg/kg, respectively. In Fe-rohrensteins, the Pb and Zn contents are 42 % and 17 % of their concentrations in fine earth, respectively. Since some part of heavy metals is precipitated at the redox microbarriers around concretions (Fe-rohrensteins), it is removed from the biological cycle.
اظهر المزيد [+] اقل [-]DNA-protein cross-links involved in growth inhibition of rice seedlings exposed to Ga
2015
Yu, Xiao-Zhang | Zhang, Xue-Hong
Hydroponic experiments were conducted with rice seedlings (Oryza sativa L. cv. XZX45) exposed to gallium nitrate (Ga³⁺) to investigate the accumulation of Ga in plant tissues and phytotoxic responses. Results showed that phyto-transport of Ga was apparent, and roots were the dominant site for Ga accumulation. The total accumulation rates of Ga responded biphasically to Ga treatments by showing increases at low (1.06–8.52 mg Ga/L) and constants at high (8.52–15.63 mg Ga/L) concentrations, suggesting that accumulation kinetics of Ga followed a typical saturation curve. Higher amount of Ga accumulation in plant tissues led to significant inhibition in relative growth rate and water use efficiency in a dose-dependent manner. DNA-protein cross-links (DPCs) analysis revealed that overaccumulation of Ga in plant tissues positively stimulated formation of DPCs in roots. Likewise, the measure of root cell viability evaluated by Evan blue uptake showed a similar trend. These results suggested that Ga can be absorbed, transported, and accumulated in plant materials of rice seedlings. Overaccumulation of Ga in plant tissues provoked the formation of DPCs in roots, which resulted in cell death and growth inhibition of rice seedlings.
اظهر المزيد [+] اقل [-]Multielemental analysis of 20 mushroom species growing near a heavily trafficked road in Poland
2016
Mleczek, M. | Niedzielski, P. | Kalač, P. | Budka, A. | Siwulski, M. | Gąsecka, M. | Rzymski, P. | Magdziak, Z. | Sobieralski, K.
The aim of this work was to compare 10 mostly edible aboveground and 10 wood-growing mushroom species collected near a heavily trafficked road (approximately 28,000 vehicles per 24 h) in Poland with regard to their capacity to accumulate 26 trace elements (Ag, Al, As, Au, B, Ba, Bi, Cd, Co, Cr, Cu, Fe, Ga, Ge, In, Li, Mn, Ni, Pb, Re, Sb, Se, Sr, Te, Tl, and Zn) in their fruit bodies in order to illustrate mushroom diversity in element accumulation. All analyses were performed using an inductively coupled plasma optical emission spectrometry (ICP-OES) spectrometer in synchronous dual view mode. The aboveground species had significantly higher levels of 12 elements, including Ag, As, Pb, and Se, compared to the wood-growing species. An opposite relationship was observed only for Au, Ba, and Sr. The results of principal component analysis (PCA) and hierarchical cluster analysis (HCA) implied some new relationships among the analyzed species and elements. Of the analyzed mushroom species, lead content in Macrolepiota procera would seem to pose a health risk; however, at present knowledge regarding lead bioaccessibility from mushrooms is quite limited.
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