Two thousand years of atmospheric rare earth element (REE) deposition as revealed by an ombrotrophic peat bog profile,Jura Mountains,Switzerland

A peat core from a Swiss bog represents 2110 14C years of peat accumulation and provides a continuous record of atmospheric rare earth element (REE) deposition. This is the first study providing a time-series of all REE originating from the atmosphere. Concentrations of the 14 REE (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) were determined using inductively coupled plasma-mass spectrometry (ICP-MS) after dissolution of 200 mg aliquots of age-dated peat samples with 3 ml HNO3 and 0.1 ml HBF4 at 240 degrees C in a microwave autoclave. Strict quality control schemes were applied to ensure the accuracy of the applied analytical methodology. Previous analyses of selected REE by instrumental neutron activation analysis (INAA) in the same set of peat samples revealed that INAA frequently under- or overestimated REE concentrations in a systematic manner. Concentration profiles obtained for all REE were almost identical, except for Ce and Eu. Calculation of enrichment factors (EF) revealed a distinct depletion of heavy REE relative to light REE in peat samples since the beginning of the 19th century which marks the onset of the Industrial Revolution in Europe, suggesting a pronounced influence by anthropogenic activities. Enrichments of REE calculated using Sc as a reference element exceeded unity, relative to the Upper Continental Crust. Overall, EF in all peat samples ranged from 1.96 for Sm to 2.34 for Gd, with considerably lower EF for Ce (1.82) and Eu (1.44), respectively. A significant enrichment of all REE which may have been caused by military activities, was observed in the peat sample dating from World War II (1944); this exceptional sample, however, is not enriched in Ce. The concentration profiles of REE were similar but not identical to those of other lithogenic, conservative reference elements such as Sc, Y, Al, Zr and Ti. While it has been suggested that individual REE concentrations or the sum of REE can be used as a reference parameter to calculate crustal EF in environmental samples the data presented here indicates that anthropogenic emissions of REE cannot simply be ignored.     

An ultrasound accelerated sequential extraction method and its application for element partitioning studies in compost from mixed waste streams

A rapid ultrasound accelerated sequential extraction procedure is presented which is modified from the standard BCR protocol and validated using the BCR 601 reference material. The method is accelerated at the extraction steps: for example, in the standard method each extraction step takes 16 h whereas with the ultrasonic extraction method developed in this work each step took 15 min. This means a further step can be included in the protocol without greatly increasing the experimental time. An extraction with pyrophosphate solution was therefore included to provide more information about the interaction between the elements and humic substances during the composting process. The new method has been applied to monitoring the metal partitioning behaviours in a composting process involving mixed waste streams. The metal partitioning profiles obtained from this new method show that in many cases composting tends to redistribute the metals from more labile forms to combined forms, especially to forms combined with humic substances.     

Source characterisation of atmospheric platinum group element deposition into an ombrotrophic peat bog

Platinum, palladium, rhodium, iridium and osmium were found to be enriched relative to their expected natural concentrations in peat samples from Thoreau's Bog, an ombrotrophic peat bog in Concord, Massachusetts. The source of osmium into the bog was determined from its isotopic composition (187Os/188Os). Osmium is composed of 4% lithogenic osmium from atmospheric soil dust, 41% of anthropogenic osmium and 55% of osmium from a non-lithogenic, non anthropogenic source, with rain being a likely candidate for the latter. Significant anthropogenic and rain contributions are also expected for iridium. In contrast, platinum, palladium and rhodium are almost exclusively anthropogenic. The larger enrichments of platinum, palladium and rhodium indicate that automobile catalysts are the source of platinum group elements to Thoreau's bog. The bog is located approximately 300 m from a major road and, therefore, the occurrence of platinum elements is evidence for regional dispersion of these metals. The absence of a clear trend following the introduction of catalysts indicates that platinum group elements are not quantitatively conserved in peat with downward leaching and plants playing an important role in the accumulation of platinum group elements.     

Biological monitoring of particulate pollutants during exploration work at a niobium mineralization in Greenland

The purpose of this investigation was to monitor airborne dipersion of particulates in connection with exploration activities at a niobium-mineralization in the Sarfartoq area, SW Greenland, during the summer of 1989, and to provide a basis for monitoring strategies in later phases of the development of the mining site. During three periods moss bags were exposed at 9 stations close to the outcrop and at 3 background stations, and indigenous lichens and mosses were sampled before and after the exploration work.Analyses of element concentrations showed that the natural enrichment of elements in the indigenous vegetation is restricted to areas immediately at or on the outcrop. The elements found in elevated concentrations were Nb, La, Ce, Th and U.The moss bags and the indigenous monitor organisms showed rises in concentrations of the elements Nb, Ce, Cd, Pb and Zn after the exploration activities during the summer. This shows that some dispersion of dust has occurred in the area.     

SEC-ICP-MS studies for elements binding to different molecular weight fractions of humic substances in compost extract obtained from urban solid waste

In this work, the speciation of elements in compost was studied with emphasis on their binding to humic substances. In order to assess the distribution of As, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, U, Th and Zn among molecular weight fractions of humic substances, the compost extract (extracted by 0.1 mol l(-1) sodium pyrophosphate) was analyzed by size exclusion chromatography coupled on-line with UV-Vis spectrophotometric and ICP-MS detection. Similar chromatograms were obtained for standard humic acid (Fluka) and for compost extract (254 nm, 400 nm) and three size fractions were operationally defined that corresponded to the apparent molecular weight ranges > 15 kDa, 1-15 kDa and < 1 kDa. The percentage of total element content in compost that was leached to the extract ranged from 30% up to 100% for different elements. The elution profiles of Co, Cr, Cu, Ni and Pb (ICP-MS) followed that of humic substances, while for other elements the bulk elution peak matched the retention time observed for the element in the absence of compost extract. Spiking experiments were carried out to confirm elements' binding and to estimate the affinity of individual elements for humic substances derived from compost. The results obtained indicated the following order of decreasing affinity: Cu > Ni > Co > Pb > Cd > (Cr, U, Th) > (As, Mn, Mo, Zn). After standard addition, further binding of Cu, Ni and Co with the two molecular weight fractions of humic substances was observed, indicating that humic substances derived from compost were not saturated with these elements.     

Determination of road dust loadings and chemical characteristics using resuspension

The contribution of fugitive dust from traffic to air pollution can no longer be ignored in China. In order to obtain the road dust loadings and to understand the chemical characteristics of PM₁₀ and PM_2.5 from typical road dust, different paved roads in eight districts of Beijing were selected for dust collection during the four seasons of 2005. Ninety-eight samples from 28 roads were obtained. The samples were resuspended using equipment assembled to simulate the rising process of road dust caused by the wind or wheels in order to obtain the PM₁₀ and PM_2.5 filter samples. The average road dust loading was 3.82 g m^− 2, with the highest of 24.22 g m^− 2 being in Hutongs in the rural–urban continuum during winter. The road dust loadings on higher-grade roads were lower than those on lower-grade roads. Attention should be paid to the pollution in the rural–urban continuum areas. The sums of element abundances measured were 16.17% and 18.50% for PM₁₀ and PM_2.5 in road dust. The average abundances of OC and EC in PM₁₀ and PM_2.5 in road dust were 11.52%, 2.01% and 12.50%, 2.06%, respectively. The abundance of elements, water-soluble ions, and OC, EC in PM₁₀ and PM_2.5 resuspended from road dust did not change greatly with seasons and road types. The soil dust, construction dust, dust emitted from burning coal, vehicle exhaust, and deposition of particles in the air were the main sources of road dust in Beijing. Affected by the application of snow-melting agents in Beijing during winter, the amount of Cl⁻ and Na⁺ was much higher during that time than in the other seasons. This will have a certain influence on roads, bridges, vegetations, and groundwater.     

Monitoring the Trihalomethanes Present in Water After Treatment with Chlorine Under Laboratory Condition

In this work assays involving chlorinated water samples, which were previous spiked with humic substances or algae blue green and following the production of the THMs for 30 days is described. To implement the assays, five portions of 1,000 ml of water were stored in glass bottles. The water samples were treated with solutions containing 2, 3, 4 and 5 mg l⁻¹ chlorine. The samples aliquots (60 ml) were transferred into the glass vials, 10 ml were removed to have a headspace and 100 μl of the 10 mg l⁻¹ pentafluortoluene bromide solution was added to each vial. The extraction step was performed by adding 10 g of Na₂SO₄ followed by 5 ml of n-pentane. The vials were stopped with a TFE-faced septum and sealed with aluminum caps. The generated THMs were determined by gas chromatography with electron capture detector using reference solutions with concentration ranging from 8 to 120 μg l⁻¹ THMs. Three assays were monitored during 30 days and chloroform was the predominant compound found in the water samples, while other species of THMs were not detected. The results showed that when the chlorine concentration was increased in water samples containing algae the concentration of THM varied randomly. Nevertheless, in water samples containing humic substances the increase of the THM concentration presented a relationship with the chlorine concentration. It was also observed that chloroform concentration increased with the elapsed time up to one and six days to water samples spiked with humic substances and algae blue green, respectively and decreased along 30 days. By other hand, assays performed using water samples containing decanted algae material showed that THM was not generated by the chlorine addition.     

Anthropogenic gadolinium anomalies and rare earth elements in the water of Atibaia River and Anhumas Creek,Southeast Brazil

The concentrations of rare earth elements (REE), measured in water samples from Atibaia River and its tributary Anhumas Creek, Brazil, present excess of dissolved gadolinium. Such anthropogenic anomalies of Gd in water, already described in other parts of the world, result from the use of stable and soluble Gd chelates as contrast agents in magnetic resonance imaging. Atibaia River constitutes the main water supply of Campinas Metropolitan area, and its basin receives wastewater effluents. The REE concentrations in water samples were determined in 0.22-μm pore size filtered samples, without and after preconcentration by solid-phase extraction with bis-(2-ethyl-hexyl)-phosphate. This preconcentration method was unable to retain the anthropogenic Gd quantitatively. The probable reason is that the Gd chelates dissociate slowly in acidic media to produce the free ion that is retained by the phosphate ester. Strong correlations between Gd and constituents or parameters associated with effluents confirmed the source of most Gd in water samples as anthropogenic. The shale-normalized REE patterns of Atibaia River and Anhumas Creek water samples showed light and heavy REE enrichment trends, respectively. Also, positive Ce anomalies in many Atibaia River samples, as well as the strong correlations of the REE (except Gd) with terrigenous elements, imply that inorganic colloidal particles contributed to the REE measured values.     

The effects of anthropogenic particulate emissions on roadway dust and Nerium oleander leaves in Messina (Sicily, Italy)

Complementary studies on the inorganic chemical composition of Nerium oleander leaves collected in the town of Messina (Sicily, Italy) and seven grain-size fractions of local roadway dust have been carried out. Data and maps are presented to show that the particulate matter present in the air of Messina contains trace elements significantly in excess with respect to the average continental earth crust. The anomalies follow the outline of the urban area, the highest concentrations of trace elements being observed where traffic density is highest. Chemical and isotopic analyses of both road dust and Nerium oleander leaves indicate that Pb contamination still characterizes roads with heavy traffic. In addition to Pb, other metals such as Pt, Pd, Sb, Au, Br, Zn, Cu, Mo, and Cd are significantly enriched in roadway dust, indicating their common anthropogenic origin, especially from traffic. SEM/EDS study of some roadway dust particles has shown the presence of gypsum probably of secondary origin, mixed particles formed by coagulation or gas-to-particle conversion, and porous spherical particles apparently emanating from combustion processes.     

抚顺市PM10中元素分布特征及来源分析

为了确定抚顺市PM10中元素的浓度特征及其来源,于2006—2007年的采暖季、风沙季和非采暖季在抚顺市的6个采样点采集PM10样品,并用等离子体原子发射光谱法(ICP-AES)测定样品中Ti、Al、Mn、Mg、Ca、Na、K、Cu、Zn、As、Pb、Cr、Ni、Co、Cd、Fe、V等17种元素的含量。结果表明,Al、Mg、Ca、Na、K、Mn、Fe等地壳元素在17种元素中占有较大比重,全年平均达到97.0%。富集因子分析结果表明,Cu、Zn、Pb、Cr、Co、Cd等元素在各季和各采样点明显受到人为活动影响,是典型的污染元素。主因子分析结果显示,土壤风沙尘、建筑尘、燃煤尘、道路扬尘、机动车尾气排放、金属冶炼、锰、铜、钛工业源是抚顺市PM10中元素的主要来源。     

Impact of automobile emissions on the levels of platinum and lead in Accra,Ghana

Examination of car fleet records in Accra demonstrates an increasing proportion of catalytic converter-equipped cars in the relatively old car fleet (average age 13 years) due to their import from developed countries. However, only leaded petrol is sold in Ghana. Lead anti-knocking additives, which are known to affect catalyst activity and promote thermal sintering and mechanical abrasion, may increase Pt emissions. This possible synergism prompted the concomitant determination of Pb and Pt levels in road dust and roadside soils in Ghana. Both metals followed traffic density with higher concentrations in urban areas compared to remote sites. In urban areas, the range for Pb (365 +/- 93 microg g(-1) for dust and 291 +/- 76 microg g(-1) for soil) reflects precatalyst levels in Europe and the US, while the range for Pt (39 +/- 24 ng g(-1) for dust and 15 +/- 5.3 ng g(-1) for soil) is typical for the same countries. The elevated Pt concentrations were unexpected due to recent introduction of catalysts to Ghana compared to the prolonged use of catalysts in Europe and the US.     

DBP Levels in Chlorinated Drinking Water: Effect of Humic Substances

Chlorination is the most widely used technique for disinfection of drinking water. A consequence of chlorination is the formation of Disinfection By-Products (DBPs). The formation of DBPs in drinking water results from the reaction of chlorine with naturally occurring organic materials, principally humic and fulvic acids. This paper focuses on the effect of humic substances on the formation of twenty-four compounds belonging to different categories of DBPs. This investigation was conducted in two water treatment plants in Greece, Menidi and Galatsi, from July 1999 to April 2000. Humic substances were determined by the diethylaminoethyl (DEAE) method with subsequent UV measurement. The techniques used for the determination of DBPs were liquid-liquid extraction, gas chromatography and mass spectrometry. The concentrations of DBPs were generally low. Total trihalomethanes (TTHMs) ranged from 5.1 to 24.6 microg L(-1), and total haloacetic acids (HAAs) concentration ranged from 8.6 to 28.4 microg L(-1), while haloaketones (HKs) and chloral hydrate (CH) occurred below 1 microg L(-1). The content of humic substances was found to influence the formation of DBPs and especially TTHMs, trichloroacetic acid (TCA), dibromoacetic acid (DBA), CH, 1,1-dichloropropanone (1.1-DCP) and 1,1,1-trichloropropanone (1,1,1-TCP). Seasonal variation of TTHMs and HAAs generally followed that of humic substances content with peaks occurring in autumn and spring. The trends of 1,1-DCP, 1,1,1-TCP and CH formation seemed to be in contrast to TTHMs and HAAs. Trends of formation of individual compounds varied in some cases, probably due to influence of parameters other than humic substances content. Statistical analysis of the results showed that the concentrations of TTHMs, CH, 1,1-DCP, 1,1,1-TCP, TCA and DBA are strongly affected from humic substances content (at 0.01 confidence level). The opposite is true for dichloroacetic acid (DCA) concentration. Humic substances also vary to a statistically significant degree during different months, as well as the concentrations of TTHMs, CH, 1,1-DCP, 1,1,1-TCP, TCA and DCA. The variance of DBA was not statistically significant. Regarding the effect of sampling station, humic substances content showed no statistically significant difference between the two raw water sources studied.     

Collaborative study to improve the quality control of rare earth element determinations in environmental matrices

In order to control the quality of rare earth determinations in environmental matrices, the Standards, Measurements and Testing Programme (formerly Community Bureau of Reference, BCR) of the European Commission has started a project, the final aim of which is to certify four types of matrices (tuna muscle, mussel tissue, aquatic plant and estuarine sediment) for their contents of a range of rare earth elements (Sc, Y and the lanthanides: La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu). The elements U and Th were added to the study. The first part of this project consisted of an interlaboratory study which aimed to test the feasibility of preparation of environmental reference materials and to detect and remove most of the pitfalls observed in rare earth determinations. This paper presents the preparation of the four matrices for the intercomparison study and for the candidate reference material. The main results are presented of the interlaboratory study that was carried out prior to the certification campaign. This collaborative trial is the first attempt ever carried out at this scale to evaluate the state-of-the-art of rare earth determinations in the environment. Its impact on the improvement of chemical measurements will have positive effects on the comparability of data necessary for environmental monitoring.     

石家庄市大气颗粒物元素组分特征分析

为研究石家庄市大气颗粒物的污染特征及其来源,于2013年4—5月在主城6区分别采集TSP、PM10和PM2.5颗粒物样品,利用ICP-MS分析其中的22种元素浓度。结果表明,石家庄市城区Ca、Fe元素在各粒径颗粒物中含量都较高,PM2.5中的S、K含量较高,PM10和TSP中Mg、Al的浓度相对较高。颗粒物的主要来源为燃煤尘、道路尘和建筑尘,TSP、PM10和PM2.5具有较好的统计相关性和同源性。     

Diurnal trends in coarse particulate matter composition in the Los Angeles Basin

To investigate the diurnal profile of the concentration and composition of ambient coarse particles, three sampling sites were set up in the Los Angeles Basin to collect coarse particulate matter (CPM) in four different time periods of the day (morning, midday, afternoon and overnight) in summer and winter. The samples were analyzed for total and water-soluble elements, inorganic ions and water-soluble organic carbon (WSOC). In summer, highest concentrations of CPM gravimetric mass, mineral and road dust, and WSOC were observed in midday and afternoon, when the prevailing onshore wind was stronger. In general, atmospheric dilution was lower in winter, contributing to the accumulation of air pollutants during stagnation conditions. Turbulences induced by traffic become a significant particle re-suspension mechanism, particularly during winter night time, when mixing height was lowest. This is evident by the high levels of CPM mass, mineral and road dust in winter overnight at the near-freeway sites located in urban Los Angeles, and to a lesser extent in Riverside. WSOC levels were higher in summer, with a similar diurnal profile with mineral and road dust, indicating that they either share common sources, or that WSOC may be adsorbed or absorbed onto the surfaces of these dust particles. In general, the contribution of inorganic ions to CPM mass was greater in the overnight sampling period at all sampling sites, suggesting that the prevailing meteorological conditions (lower temperature and higher relative humidity) favor the formation of these ions in the coarse mode. Nitrate, the most abundant CPM-bound inorganic species in this basin, is found to be predominantly formed by reactions with sea salt particles in summer. When the sea salt concentrations were low, the reaction with mineral dust particles and the condensation of ammonium nitrate on CPM surfaces also contributes to the formation of nitrate in the coarse mode.     

Chemical speciation studies on DU contaminated soils using flow field flow fractionation linked to inductively coupled plasma mass spectrometry (FlFFF-ICP-MS)

Flow field flow fractionation (FlFFF) in combination with inductively coupled plasma mass spectrometry (ICP-MS) was used to study the chemical speciation of U and trace metals in depleted uranium (DU) contaminated soils. A chemical extraction procedure using sodium pyrophosphate, followed by isolation of humic and fulvic substances was applied to two dissimilar DU contaminated sample types (a sandy soil and a clay-rich soil), in addition to a control soil. The sodium pyrophosphate fractions of the firing range soils (Eskmeals and Kirkcudbright) were found to contain over 50% of the total U (measured after aqua regia digestion), compared to approximately 10% for the control soil. This implies that the soils from the contaminated sites contained a large proportion of the U within more easily mobile soil fractions. Humic and fulvic acid fractions each gave characteristic peak maxima for analytes of interest (Mn, Fe, Cu, Zn, Pb and U), with the fulvic acid fraction eluting at a smaller diameter (approximately 2.1 nm on average) than the humic fraction (approximately 2.4 nm on average). DU in the fulvic acid fraction gave a bimodal peak, not apparent for other trace elements investigated, including natural U. This implies that DU interacts with the fulvic acid fraction in a different way to all other elements studied.     

A preliminary investigation of BDE-209, OCPs, and PAHs in urban road dust from Yangtze River Delta, China

Urban road dust samples were collected from different land use areas in Suzhou, Wuxi, and Nantong, Yangtze River Delta, China. The dust samples were analyzed for the levels and compositional profiles of deca-polybrominated diphenyl ethers (Deca-BDE), 22 organochlorine pesticides (OCPs), and 16 polycyclic aromatic hydrocarbons (PAHs). The levels of BDE-209, ∑OCPs, and ∑PAHs in samples ranged from 4.01–1,439 μg/kg, 3.15–615 μg/kg, and 2.24–58.2 mg/kg, respectively. PAHs were the predominant target compounds in road dust samples, comprising on average 97.7 % of total compounds. The spatial gradient of the pollutants (commercial/residential area> industrial area > urban park concentrations) was observed in the present study. The results indicated that the levels of BDE-209, OCPs, and PAHs observed in road dust were usually linked to anthropogenic activities in the urban environment. In addition, there might be a reflection of current usage or emissions of OCPs in urban environment.     

Aerosol size distribution and mass concentration measurements in various cities of Pakistan

During March and April 2010 aerosol inventories from four large cities in Pakistan were assessed in terms of particle size distributions (N), mass (M) concentrations, and particulate matter (PM) concentrations. These M and PM concentrations were obtained for Karachi, Lahore, Rawalpindi, and Peshawar from N concentrations using a native algorithm based on the Grimm model 1.109 dust monitor. The results have confirmed high N, M and PM concentrations in all four cities. They also revealed major contributions to the aerosol concentrations from the re-suspension of road dust, from sea salt aerosols, and from vehicular and industrial emissions. During the study period the 24 hour average PM(10) concentrations for three sites in Karachi were found to be 461 μg m(-3), 270 μg m(-3), and 88 μg m(-3), while the average values for Lahore, Rawalpindi and Peshawar were 198 μg m(-3), 448 μg m(-3), and 540 μg m(-3), respectively. The corresponding 24 hour average PM(2.5) concentrations were 185 μg m(-3), 151 μg m(-3), and 60 μg m(-3) for the three sites in Karachi, and 91 μg m(-3), 140 μg m(-3), and 160 μg m(-3) for Lahore, Rawalpindi and Peshawar, respectively. The low PM(2.5)/PM(10) ratios revealed a high proportion of coarser particles, which are likely to have originated from (a) traffic, (b) other combustion sources, and (c) the re-suspension of road dust. Our calculated 24 hour averaged PM(10) and PM(2.5) concentrations at all sampling points were between 2 and 10 times higher than the maximum PM concentrations recommended by the WHO guidelines. The aerosol samples collected were analyzed for crustal elements (Al, Fe, Si, Mg, Ca) and trace elements (B, Ba, Cr, Cu, K, Na, Mn, Ni, P, Pb, S, Sr, Cd, Ti, Zn and Zr). The averaged concentrations for crustal elements ranged from 1.02 ± 0.76 μg m(-3) for Si at the Sea View location in Karachi to 74.96 ± 7.39 μg m(-3) for Ca in Rawalpindi, and averaged concentrations for trace elements varied from 7.0 ± 0.75 ng m(-3) for B from the SUPARCO location in Karachi to 17.84 ± 0.30 μg m(-3) for Na at the M. A. Jinnah Road location, also in Karachi.     

城市环境中的PGEs研究进展

PGEs及其化合物是一类高发生率的致敏物,部分PGEs化合物还具有致癌效应.PGEs排放带来的环境问题已成为近年来国际环境问题研究热点之一,但尚未引起国内学术界足够重视,相关报道较少.本文从PGEs在环境中的富集特征、分布规律与来源、迁移转化及其生物有效性等方面对国内外城市环境PGEs研究现状进行了系统的阐述与总结,并...     

Collaborative evaluation of the analytical state-of-the-art of platinum, palladium and rhodium determinations in road dust

In order to control the quality of platinum, palladium and rhodium determinations in road dust, the Standards, Measurements and Testing Programme (formerly BCR) of the European Commission has started a project, the final aim of which is to certify a road dust reference material for its contents of platinum group elements. The first part of this project consisted of an interlaboratory study, which aimed to test the feasibility of the preparation of a candidate road dust reference material and to detect and remove most of the pitfalls observed in platinum, palladium and rhodium determinations. This paper presents the main results of this interlaboratory study carried out prior to the certification campaign. The concordance of the data obtained by the participating laboratories for the three elements was considered to reflect the state-of-the-art and was encouraging enough to decide on the organization of a certification campaign to be conducted during the year 2000. The progress made with respect to the analytical state-of-the-art for these elements will be of great benefit to the quality of measurements carried out in environmental monitoring in this particular field.