Enrichment Factors Of Pb Research Articles

Guleman Kromit Yatağı Çevresindeki İnci Çayı Sedimentlerindeki Metal Kirliliğinin Temel Değer ve Ortalama Yerkabuğu Değerleri Tarafından Değerlendirilmesi (Alacakaya-Elazığ), Türkiye

The total concentration of elements in the Inci stream sediments on the drainage network of chromite deposits was determined to evaluate the level of contamination by natural background, the average of ultramafic and mafic rocks in this study. The average concentration shows that toxic heavy metals originated from mineraliszing in the Inci stream sediments that have a controlling influence on accumulation and transportation both lithologically and anthropogenically. The metal enrichment factors of Pb, As, Ni, Sr, and Ba, and geoaccumulation factor values (Igeo) of Pb, As, Sr, Ba, and Rb indicated that these values are higher than background values and heavily contaminated. The highest metal concentrations and assessments of contaminants were obtained from ultramafic rock normalization. Enrichment factor (EF), contamination factor (CF), and Igeo values indicate that primary ore metals are represented by Pb, Cu, Mn, Ni, and Cr. Cr's enrichment factor (EF) is moderate contamination due to the high Cr concentration in the host rock. However, Cr is extremely contaminated according to the Earth's average in the stream sediments around the chromites deposit. The calculated Cu, Ni, and Cr threshold values are higher than the probable effect level (PEL) and threshold effect level (TEL). That is why these regions should be evaluated for relationships between human health and geochemistry in further multidisciplinary studies and considered important in terms of potential Cr, Cu, Mn, Ni, Pb and Zn mineralization.

Historical trends and pollution assessment of heavy metals in core sediments from the Jiangsu offshore area, China

To assess the historical changes and pollution status of heavy metals, core sediments from the Jiangsu offshore area of China were systematically sampled and analyzed to determine the concentrations of Cu, Pb, Zn, Cr, Cd, As, Hg, Li, Ni, and Co. The stratigraphic framework of the SYS-1501 core was identified based on sedimentary structures, sedimentary facies, grain size, and comparison with seismic reflections and other well-studied cores from adjacent areas. The Pearson’s correlation coefficient, enrichment factor (EF), geoaccumulation index (Igeo), and principal component analysis (PCA) were used to distinguish the sources and assess the pollution risk of heavy metals. The results showed no elemental enrichment or contamination in the core sediments, and the high EF and Igeo values of Pb, As, Hg, and Li may be related to the selected background values of these metals. Except for Mn, all other metals and TOC exhibited similar vertical distribution patterns that were closely related to the mean grain size (Mz). Almost all the heavy metals were positively correlated with Al, Fe, and Mz, and all had high loadings on PC1, indicating that they are naturally sourced. Manganese (Mn) had a high loading on PC2, mainly representing the effect of marine authigenic elements on the sediments. Historical changes in the heavy metals in the core sediments were predominantly related to the sedimentary environment, sediment sources, and Mz.

Pollution characteristics and human health risks of PM2.5-bound heavy metals: a 3-year observation in Suzhou, China.

This study aimed to analyze the temporal trends, pollution levels, and health risks associated with eleven PM2.5-bound heavy metals (Sb, Al, As, Hg, Cd, Cr, Mn, Ni, Pb, Se and Tl). A total of 504 PM2.5 samples were collected in Suzhou from January 2019 to December 2021. The pollution levels were estimated based on enrichment factors (EFs) which can be used to calculate the enrichment of heavy metals in PM2.5 and determine whether the concentrations of PM2.5-bound heavy metals are influenced by the crustal or anthropogenic sources, and the health risk of PM2.5-bound heavy metals via inhalation was assessed following US EPA's Risk Assessment Guidance for Superfund (RAGS). The annual average concentration of PM2.5 was 46.76μgm-3, which was higher than the WHO recommended limit of 5μgm-3. The average of the sum of eleven PM2.5-bound heavy metals was 180.61ngm-3, dominated by Al, Mn, and Pb. The concentration of PM2.5 in 2020 was significantly lower than that in 2019 and 2021. The PM2.5 and PM2.5-bound heavy metal concentrations in winter and spring were significantly higher than those in autumn and summer. The EF of As, Cr, Cd, Hg, Ni, Pb, Sb, Mn, Se, and Tl was higher than 10, indicating they were mainly from anthropogenic sources. Exposure to a single non-carcinogenic heavy metal via inhalation was unlikely to cause non-carcinogenic effects (HQ < 1), but the integrated non-carcinogenic risks should be taken seriously (HI > 1). The cumulative carcinogenic risks from the carcinogenic elements were exceeding the lower limit (1 × 10-6) of the acceptable risk range. The carcinogenic risks of As and Cr(VI) contributed 60.98% and 26.77%, respectively, which were regarded as two key carcinogenic risk factors. Overall, the government policies and countermeasures for the PM2.5 pollution control should be performed not only based on the PM2.5 concentration but also based on the PM2.5-bound heavy metals and their health risks for the local residents.

Mineral dust and lead deposition from land use and metallurgy in a 4800-year-old peat record from the Central Alps (Tyrol, Austria)

Humans have occupied the Alps over most of the Holocene. Yet, continuous records on the impact of using montane resources and landscapes are scarce or confined to segregated areas or periods. We present a high-resolution geochemical record of the last 4800 years from the ombrotrophic peatland Piller Moor in the Central Alps (Tyrolean Oberland, western Austria), using inductively coupled mass plasma spectrometry (ICP-MS) and highly efficient inter-calibrated portable X-ray fluorescence analysis (pXRF). Fluctuations of metal enrichment factors (EF) for lead (Pb), copper (Cu), zinc (Zn) and antimony (Sb), accumulation rates of anthropogenic lead (Pbanth AR) and mineral matter (MAR), based on titanium (Ti), are in line with archaeological and pollen evidence for human presence and environmental change. Periods of intensified, erosive land use are indicated by MAR around 4400 cal BP, 3400 cal BP and, very prominently, at 2400 cal BP. After low MAR in the early Middle Ages, soil disturbances reappear around 1200 cal BP (750 AD), after 200 cal BP (1750 AD) and during the 20th century AD. We found evidence that metallurgy was practised in the area as early as 4450 cal BP, again from 3500 to 2900 cal BP and episodically between 2400 and 1400 cal BP. The Central Alps were presumably a source of increased Pb-emissions in the post-Roman period from 1500 to 1400 cal BP (450–550 AD). Generally, our findings suggest that mining predates archaeological and historical evidence. Following a continuous increase since the Middle Ages, atmospheric Pb EF and Pbanth AR peak around 1980 AD. The record of mineral atmospheric input illustrates the notable impact of human activities on soil erosion and dust entrainment in the Central Alps. Furthermore, links between Little Ice Age cold phases and reduced human impact and mining are established. Our high-resolution peat-geochemistry data quantifies atmospheric deposition of mineral matter and Pb, which act as proxies for landscape evolution and metallurgy on a local and regional scale. It provides new insights and a deeper understanding of the interaction of climate, environment and humans in mountainous landscapes like the Central Alps.

Trace elements accumulation over a century in sediment cores from a tectonic lake on the Qinghai-Tibet plateau: Source identification and risk assessment

A record of trace elements in lake sediment can help in assessing the impact of anthropogenic activities on aquatic environments. In the present work, the trace elements profiles (Cu, Cr, Pb, Zn, As, and Cd) were determined in four sediment cores (QH01, QH02, QH07, and Z04) collected in 2012 and 2014 from Lake Qinghai to reconstruct the history of anthropogenic activity in the watershed and to evaluate the pollution status and eco-environmental risks of a typical Third Pole lake environment over the past century. The concentrations of Cu, Cr, Pb, Zn, As, and Cd in these studies ranged between 19.4 and 34.2 μg g−1, 35.6–53.6 μg g−1, 3.10–26.8 μg g−1, 56.4–93.5 μg g−1, 6.20–15.3 μg g−1, and 0.086–0.572 μg g−1, respectively. Statistical analyses indicated that the Pb, Zn, and Cd contents combination of coal, gasoline burning, and agricultural activities in the Lake Qinghai catchment and larger-scale atmospheric inputs during the past 60 years. The enrichment factors for Pb, Zn, and Cd in the sediments of Lake Qinghai are considered to be related to the region of the Qinghai-Tibet Plateau and national socioeconomic development. Enrich factor of Cd values was higher than 3.5 and maximum values of the geo-accumulation index of Pb and Cd were observed in the top layer of the sediment (0–2 cm), indicating moderate contamination. The RI values suggest that the risks to the ecological environment of Lake Qinghai are increasing since the 1950s. The results of this study illustrate that Lake Qinghai is still experiencing high trace elements pollution pressure due to the rapid environmental changes caused by anthropogenic activities on the remote and isolated Qinghai-Tibet Plateau.

Metals in Lake Sediments as Indicators of Human Activities in Prehistory: Case Study of the Southeastern Baltic, Kamyshovoe Lake

This paper presents the results of geochemical research on the Kamyshovoe Lake sediments (Kaliningrad oblast, Russian Federation). The study of Pb, Ni, Zn, As, Co and Cu concentration and enrichment factors (EF) combined with the results of the lithological, geochronological, magnetic susceptibility and microcharcoal studies revealed possible anthropogenic sources of metals in southeastern Baltic lake sediments from the Neolithic to the Medieval period. Increasing Co EF value and peaks of the Pb EF in Kamyshovoe Lake sediments, starting from ~6000 cal yr BP in the Neolithic, probably show the growing role and usage of metals as dyes and fixatives. Since ~3100 cal yr BP, in the end of the Bronze Age, a simultaneous increase in the content of indicators of metallurgical production Pb, Ni, Zn and As, coinciding with growth of the microcharcoal curve, can show a growing demand for metal objects in the southeastern Baltic region and the input of the local or regional ancient metallurgy into the metal pollution of the lake sediments.

Risk assessment and binding mechanisms of potentially toxic metals in sediments from different water levels in a coastal wetland

The excessive accumulation of potentially toxic metals (Pb and Cd) in coastal wetlands is among the main factors threatening wetland ecosystems. However, the effects of water table depth (WTD) on the risk and binding mechanisms of potentially toxic metals in sediments remain unclear. Here, sediments from different WTD obtained from a typical coastal wetland were evaluated using a newly developed strategy based on chemical extraction methods coupled with high-resolution spectroscopy. Our findings indicated that the WTD of the coastal wetland fluctuates frequently and the average enrichment factor for Pb was categorized as minor, whereas Cd enrichment was categorized as moderate. High-resolution spectroscopy techniques also demonstrated that organic functional groups and partly inorganic compounds (e.g., Fe-O/Si-O) played a vital role in the binding of Pb and Cd to surface sediments. Additionally, mineral components rather than organic groups were mainly bound to these metals in the bottom sediments. Collectively, our findings provide key insights into the potential health effects and binding characteristics of potentially toxic metals in sediments, as well as their dynamic behavior under varying sediment depths at a microscale.

Seasonal variation of atmospheric Pb sources in Singapore - Elemental and lead isotopic compositions of PM10 as source tracer

Southeast Asia has become a hotspot of anthropogenic particulate matter (PM) emissions due to increased coal combustion, high-temperature industrial operations, vehicular traffic, and agricultural biomass burning. Lead (Pb), a criteria pollutant, bound to such PM can be hazardous when inhaled, even at extremely low concentrations. Precise and accurate source apportionment of atmospheric Pb is thus, critical in order to minimize its exposure. This study investigates the sources of atmospheric Pb in Singapore aerosol samples (PM10) using Pb isotopes and elemental composition as tracers of contamination sources. PM10 aerosol sampling was conducted over a period of 1 year from June 2017 to May 2018 to capture the seasonal variations in sources of atmospheric Pb. Elemental concentrations reveal particularly high enrichment factors for Pb, Cu, V, Ni and Zn, especially when under the influence of southwest (SW) and inter monsoon (IM) winds. Pb isotopic ratios across the three seasons (206/207Pb = 1.147˗1.150 and 208/207Pb = 2.420˗2.428) are not significantly different. The Pb isotopic signatures and V/Ni ratios for all three seasons overlap with those of gasoline, diesel and ship emissions. Moreover, V/Pb values of more than unity for SW and IM winds suggest influence of transboundary coal combustion emissions particularly from Indonesia. Consequently, using Pb isotopic fingerprints and elemental ratios, we find that the primary sources of atmospheric Pb are vehicular & ship emissions, heavy oil combustion, transboundary coal combustion emissions, waste incineration and recirculation of historic leaded gasoline.

Ecological Risk Assessment of Heavy Metal Pollution in Mangrove Sediments of the Sepang Besar River, West Coast Peninsular Malaysia

The impact of heavy metal contamination caused by human activities on mangroves, rivers, estuaries, and coastal wetlands has gained attention recently. In this study, the presence of heavy metals in the mangrove Sepang Besar River's surface sediments was examined. As, Mo, Pb, Cr, Co, Cd, Ni, and Hg concentrations in sand were measured using inductively coupled plasma mass spectrometry (ICP-MS). Across all sampling sites, Cr concentrations were the highest and Hg concentrations were the lowest. The concentration of As was found higher than shale's geochemical background value. The range of EFs for As, Mo, and Pb are 4.38 to 12.9, 1.71 to 3.67, and 0.94 to 2.68, respectively. The eight heavy metals and other environmental components were compared using the correlation coefficient. The ecological hazards posed by eight heavy metals (As, Mo, Pb, Cr, Co, Cd, Ni, and Hg) were assessed using the comprehensive enrichment factor (EF) and geo-accumulation index (Igeo). The Enrichment factor and geo-accumulation index, in particular, revealed that Arsenic is the most prevalent heavy metal pollutant in surface sediments in Sepang Besar River mangrove sediments, with some stations requiring specific attention due to high pollution levels.

Use of Radioisotope Ratios of Lead for the Identification of Historical Sources of Soil Lead Contamination in Santa Ana, California.

Lead (Pb) is an environmental neurotoxicant that has been associated with a wide range of adverse health conditions, and which originates from both anthropogenic and natural sources. In California, the city of Santa Ana represents an urban environment where elevated soil lead levels have been recently reported across many disadvantaged communities. In this study, we pursued a community-engaged research approach through which trained “citizen scientists” from the surrounding Santa Ana community volunteered to collect soil samples for heavy metal testing, a subset of which (n = 129) were subjected to Pb isotopic analysis in order to help determine whether contamination could be traced to specific and/or anthropogenic sources. Results showed the average 206Pb/204Pb ratio in shallow soil samples to be lower on average than deep samples, consistent with shallow samples being more likely to have experienced historical anthropogenic contamination. An analysis of soil Pb enrichment factors (EFs) demonstrated a strong positive correlation with lead concentrations, reinforcing the likelihood of elevated lead levels being due to anthropogenic activity, while EF values plotted against 206Pb/204Pb pointed to traffic-related emissions as a likely source. 206Pb/204Pb ratios for samples collected near historical urban areas were lower than the averages for samples collected elsewhere, and plots of 206Pb/204Pb against 206Pb/207 showed historical areas to exhibit very similar patterns to those of shallow samples, again suggesting lead contamination to be anthropogenic in origin, and likely from vehicle emissions. This study lends added weight to the need for health officials and elected representatives to respond to community concerns and the need for soil remediation to equitably protect the public.

Ecological Risk Link to Trace Metals Levels in Surface Sediments from Fresco Lagoon, Côte d’Ivoire, West Africa

Sediment contamination with trace metals remains a current problem for aquatic ecosystems management worldwide. Surface sediments from Fresco Lagoon (Côte d'Ivoire) were analyzed to assess the contamination degree of the area. Concentrations of five selected trace metals (Pb, As, Mn, Zn, and Fe) and organic matter content were determined in samples collected from ten (10) stations, from June 2019 to March 2020. Trace metals concentrations were determined using an ICP-OES Instrument, while the organic matter contents were determined by the mass loss on ignition. The results revealed organic matter contents ranged from 5.28 to 28.31% and concentrations of trace metal (in mg.kg-1 dry weight) in the following ranges: 3.68 to 38.2 for Pb, 0.98 to 19.1 for As, 19.79 to 325 for Mn, 13.78 to 461.18 for Zn, and 1269.21 to 59862.37 for Fe. Organic matter showed a positive and significant correlation with Pb and Fe. To assess the metal pollution status in the studied area, four pollution indices were also calculated: Geoaccumulation Index (Igeo), Enrichment Factor (EF), Degree of Contamination (DC), and Pollution Load Index (PLI). Based on Igeo values, the sediments of Fresco Lagoon were in the range of unpolluted to moderately polluted with As, but unpolluted with Zn, Pb, Mn, Fe. The Enrichment factors of Pb, Zn, As, Mn, and Fe were: 64.22±52.32, 107.04±111.88, 227.29±203.06, 10.25±8.76, and 52.04±47.44 respectively, suggesting that the source of those metals was more likely to be anthropogenic. The falling trend of enrichment factors was as follows: As &gt; Zn &gt; Pb &gt; Fe &gt; Mn. Moreover, the PLI values (PLI&gt;1) showed higher values at the stations closed to the urban area, due to the influence of direct external sources such as agricultural runoff, and other anthropogenic inputs. The comparison of trace metals concentrations in sediments from Fresco Lagoon with the sediment quality guidelines showed that there was no toxic risk for benthic organisms regarding arsenic, lead, and zinc. In conclusion, the results obtained for the present work have revealed the need for the best management of anthropogenic activities regarding trace metals in general, and more particularly Pb and As.

Assessment of Heavy Metal Contamination in Urban Soils of selected areas in Hilla City, Babylon, Iraq

Modern cities suffer from heavy metal pollution due to urban expansion and population increase. Heavy metals have a great impact on human health. The objective is to determine the contamination level of heavy metals Cr, Mn, Ni, Cu, Zn, As, Zr and Pb at industrial and residential in Hilla city. The mean concentration of Cr, Mn, Ni, Cu, Zn, As, Zr and Pb enrichment factors of the investigated industrial soils are 3.43, 0.74, 6.45, 3.95, 5.60, 3.44, 1.17 and 11.44, respectively. The means of Cr, Mn, Ni, Cu, Zn, As, Zr and Pb in residential soils are 3.30, 1.09, 11.40, 0.94, 2.08, 5.39, 0.9 and 3.6, respectively. The I-geo mean values of heavy elements in the industrial area may be ordered in the following: Mn&gt; Pb&gt; Ni&gt; Zn&gt; Cu&gt; As&gt; Cr&gt; Zr. While in the residential area ordered Mn&gt; Ni&gt; As&gt;Cr&gt; Pb&gt; Zn&gt; Cu &gt; Zr. Integrated Pollution Load Index categories results showed high contamination in industrial and residential areas. The main sources of heavy elements pollution in the study area has been regarded as anthropogenic sources.

Pollution Characteristics and Health Risk of Heavy Metals in Fugitive Dust Around Zhaotong City

In order to explore the pollution characteristics and health risks of heavy metals in fugitive dust around the urban areas of Zhaotong City, road dust and soil dust samples were collected in the Zhaoyang District of Zhaotong City in May 2019. The dust samples were suspended using a particle resuspension system to obtain PM2.5 (particulate matter with an aerodynamic diameter less than or equal to 2.5 μm). The concentrations of Ca, Al, Fe, Mg, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, As, Cd, and Pb in PM2.5 were quantified by ICP-MS and ICP-OES. By analyzing 10 types of heavy metals in PM2.5, the results showed that the average concentration of Mn was the highest in the soil fugitive dust, followed by Cr, Ni, Zn, Cu, Co, Pb, V, As, and Cd. The average concentration of Zn in the road fugitive dust was the highest, followed by Mn, Cu, Cr, Pb, Ni, As, Co, V, and Cd. The enrichment factor (EF) indicated that Cd was strongly enriched in the two types of fugitive dust. The EFs of Cu, Zn, and Pb in road fugitive dust showed a moderate enrichment, and they were higher than those in soil fugitive dust. Correlation and principal component analysis showed that heavy metals in the two types of fugitive dust were affected by coal burning sources. At the same time, heavy metals in soil fugitive dust were affected by agricultural activity sources, and heavy metals in road fugitive dust were affected by traffic sources. The results of the health risk assessment indicated that the carcinogenic risks of Cr, Co, Ni, As, and Cd in soil fugitive dust were higher than those in road fugitive dust. The non-carcinogenic risks of heavy metals in the two types of fugitive dust for children were higher than those for adults, and the non-carcinogenic risks of Cu, Zn, and Pb in road fugitive dust were higher than those in soil fugitive dust.

Time-series monitoring and ecological risk assessment of heavy metal pollution in Mahanadi estuary, east coast of India

Mahanadi estuary is situated in the eastern part of India with several industries along its bank, which makes the system highly vulnerable to different types of pollutants. To assess the coastal pollution due to possible heavy metal contamination in the surface sediment of the estuary, seasonal observations (pre-monsoon, post-monsoon, and winter) were made from a time-series monitoring station near the estuary mouth. The study showed that the average concentrations of nine heavy metals were in the order of Fe> Pb> Cr >Zn >Co> Cu> Ni> Cd> Hg in both pre-monsoon and post-monsoon, whereas in winter their order was Fe >Pb >Cr> Zn> Ni> Cu> Co> Cd> Hg. The one-way ANOVA of metal concentrations shows significant seasonal variations (p<0.01) except for Hg, Cu, Zn, and Fe. The high concentration of metals in post-monsoon and winter indicated seasonal influences of potential sources in the upstream. The concentrations of Cd, Pb, Co, Ni, Zn, and Hg showed prominent tidal variation, and Cd concentration was high only in ebb tide in both pre-monsoon and post-monsoon. The pollution indices — Enrichment Factor (EF), Geo-accumulation Index (Igeo), and Pollution Load Index (PLI) along with Potential Ecological Risk Assessment (PERI) were used for the environmental assessment of Mahanadi estuary sediment collected during pre-monsoon, post-monsoon, and winter season. The high EF of Pb and Cd shows contamination of sediments by these metals from external sources such as industrial and other anthropogenic activities. Pollution indices showed that the sediment of the Mahanadi estuary is not contaminated with respect to metals except Cd. Numerical Sediment Quality Guidelines, applied to assess adverse biological effects of these metals, suggested possibilities of occasional biological effect due to Cd.

Monitoring Heavy Metal Contamination in the Pineapple (Ananas comosus) Cultivated tracts of Kerala, India

Agriculture plays an important role in the sustainable development of the country. Use of chemical fertilizers escalate certain components in excess quantity thereby deteriorate the productivity and leads to unpredicted outcome. This study makes an effort to reckon the accumulation of some selected heavy metals [Lead (Pb), Nickel (Ni) and Cadmium(Cd)] and related indices [bio concentration factor(BCF) and translocation factor (TF)] from roots, leaves and fruits of pineapple plantations in Ernakulam district. Contamination factor(CF), enrichment factor(EF) and geo accumulation index (Igeo) disclose the extent of soil contamination in the pineapple cultivated regions of Ernakulam district. Root to shoot TF derived for Pb, Ni, and Cd were 0.25, 0.733 and 0.6731. TF of Pb, Ni and Cd from root to fruit was 0, 0.5 and 0.195 respectively. Values obtained for BCF of Pb, Ni and Cd in root of the pineapple plant were 0.2013,0.5758 and 0.3288. In pineapple leaves BCF showed the values 0.0503, 0.4222 and 0.2214 by Pb, Ni and Cd. Pineapple fruit showed BCF values Zero, 0.2879 and 0.0641 for Pb, Ni and Cd. Enrichment factor for Pb, Ni and Cd in pineapple cultivated areas comes under the value 4.2, 3.7 and 2.8 respectively. Furthermore, the contamination factor of Pb, Ni and Cd was 9.93, 8.26 and 6.23, respectively. The values of geo accumulation index obtained for different heavy metals pass on that the degree of pollution with respect to Pb (6.621) was very strong and extremely contaminated, heavily to extremely contaminated for Ni (5.513) and Cd (4.15).

Atmospheric Metal Biomonitoring Along a Highway Near Atlantic Rainforest Environmental Protection Areas in Southeastern Brazil.

Vehicles are quite possibly the main sources of particulate matter, and their emissions can cause damage to surrounding ecosystems. Traditional atmospheric monitoring, however, is expensive. Therefore, airborne biomonitoring is an alternative method that allows for air quality assessment. In this study, we evaluated air quality at a federal highway (BR-040) close to Atlantic Rainforest remnants by quantifying metals in biomonitor tissues by ICP-MS. Tillandsia usneoides and Tillandsia stricta plants were relocated to the investigation zone and collected after five months of exposure. Metal concentration profiles were evaluated using statistical analyses, namely exposure-to-reference (ER) ratios and enrichment factors (EF). Results indicate that V, Cr, Fe, Cu, Zn and Sn enrichment were observed in all study sites. The EF for Cr, Mn, Pb, Ni, Co, Cu, Zn, Cd, and Sn ranged from high to very high, indicating anthropogenic sources. Both species were effective atmospheric biomonitors, proving to be an important tool, mainly in areas where conventional monitoring is not possible.

Assessment of metal contamination in deposited dust of the industrial area and some streets - Aden city, Yemen

Air pollution from pollutant emissions has become a threat to the biological system and human health. The concentration levels and sources of heavy metals contamination were studied in deposited dust samples collected from various locations, including five different activity areas: industrial, highways, residential, mixed use and a remote area from contaminants in Aden, Yemen. Metal content of Cd, Pb, Cu, Zn, Co, Cr, Mn and Fe in dust was analyzed by Atomic Absorption Spectrophotometer (AAS). The results showed high concentration levels of Cd and Pb in industrial and residential areas. Deposited dust contamination was assessed by various methods: Enrichment factor (EF), Contamination factor (CF), Degree of contamination (DC) and potential ecological index (RI). The enrichment factor indicated extremely high enrichment of Cd, Pb and Zn. High EF of Cd, Pb and Zn showed that anthropogenic sources contribute a substantial amount of these metals to dust deposited. Contamination factor analysis showed that dust samples are significantly contaminated by Cd and Pb. Individual ecological risk (Er) indicated low to high contamination of Cd, but low contamination of Pb, Cr, Cu, Co and Zn. The degree of contamination (DC) and Potential ecological risk index (RI) indicated that most of the study areas demonstrated “Moderate to considerable category” risk index. The result suggest mixed origin of pollution sources; including Man-made sources, traffic sources, and lithogenic occurrences of the metals from construction sources and road construction currently in some of the sites studied.

Guideline references to levels of heavy metals in arable soils in upper Egypt

Four soil profiles were selected from four different locations in upper Egypt including Tushka, Wadi El-Nuqra, El-Kharga, and El-Dakhla to evaluate the total and dithionate-citrate-bicarbonate (DCB) extractable heavy metals (Fe, Mn, Zn, Cu, Pb, Cr and Ni) levels in these soils. The heavy metal distributions in bulk soil samples and their size fractions (clay, silt and very fine sand) were also investigated. The studied soils had a coarse texture in all locations with mildly to moderately alkaline, slightly saline and low contents of calcium carbonate and organic matter. Clay and silt fractions of these soils showed the highest total and DCB-extractable levels of these metals; whereas the very fine sand fraction contained the lowest. In comparison with the average levels of heavy metals in the world soils, the studied soils displayed levels of heavy metals within the range or less than those of world soils. A moderate or moderately severe enrichment factor (EF) values were recorded in Tushka, El-Kharga and El-Dakhla soils for Pb and moderate EF ones for Zn were found in Tushka and El-Kharga ones. On the contrary, the values of EF for other heavy metals such as Mn, Cu, Cr, and Ni at most locations were <2, showing deficient to minimal enrichment in the soils. However, the calculated contamination factor (Cf) and geo-accumulation index (Igeo) indicated that the soil samples are characterized by uncontaminated levels of all heavy metals (Igeo of < 0). Positive correlations among the total Fe, Mn, Cu and Ni suggest that these metals may be originated from the same source, mainly from a lithogenic origin. The contents of soil heavy metals in all locations were less than the globally allowable concentrations, which indicate no harmful effect of these metals. Therefore, the contents of these heavy metals can be taken as a guide reference to the levels of the heavy metals in uncontaminated Egyptian soils.

Atmospheric sources of anthropogenic and geogenic trace metals in Australian lichen and fungi

Trace metals in archived lichen and fungi samples, dating back over 158 years, were measured to ascertain their potential to record temporal shifts in atmospheric source inputs, starting from the onset of industrial activity in Australia to the present. Lichen (Cladonia n = 85; Usnea n = 47) and fungi (Trametes n = 40) samples from the greater Sydney and Melbourne areas were analysed for their total aluminium (Al), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), nickel (Ni), lead (Pb), titanium (Ti) and zinc (Zn) concentrations using inductively coupled mass-spectrometry. We determined enrichment factors (EFs) of each metal, normalised using Al concentration. All metal concentrations were input to the United States Environmental Protection Agency’s Positive Matrix Factorisation (PMF) model to determine the probable contributing sources, with Sydney (n = 81) and Melbourne (n = 91) samples considered separately. Elevated EFs for Cd, Cu, Pb and Zn (14–1211) suggest that anthropogenic inputs have influenced lichen and fungi concentrations, whilst low EFs for Fe and Ti (1–4) imply geogenic source inputs. Elevated EFs for Pb in samples from 1932 to 2002 correspond with the 70-year period of leaded petrol emissions. PMF modelling determined four distinct source factors: Factor 1 – Cr, Co, Fe, Ni, Zn (19.8 % of the total recovered mass) corresponding to metalliferous industries; Factor 2 – Cd, Cu, Zn (5.3 %) typical of smelting, mining and coal combustion emissions; Factor 3 – Pb (6.6 %) dominated by leaded petrol emissions; Factor 4 – Al, Fe and Ti (68.2 %) relating to geogenic sources. The data show that archived Australian lichen and fungi samples provide effective biomarker proxies for atmospheric trace metal contamination. These new data, extending back to the mid-1800s, provide a more nuanced understanding of anthropogenic atmospheric pollution sources since the onset of post European industrialisation on the Australian continent.

Insights into leaded gasoline registered in mud depocenters derived from multivariate statistical tool: southeastern Brazilian coast.

Lead has been widely used since antiquity, but its uses drastically increased during the Industrial Revolution. The global emission of Pb into the environment was mainly due to tetraethyl lead added to gasoline as an antiknock additive. Because of its toxicity and neurological effects, the compound was phased out in the 1980s. Isotopic signatures are widely applied to differentiate sources of Pb; however, this is an expensive and sophisticated analysis compared to elemental analysis. Thus, this study aims to gain insight into leaded gasoline registered in mud depocenters from the southeastern Brazilian coast using multivariate statistical tools on elemental analysis data of trace elements. Seven multiple cores were collected on board the Research Vessel Alpha Crucis. Al, As, Ba, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Ni, P, Pb, Sc, Sr, V and Zn were analyzed by acid digestion and quantified by ICP-OES. Levels and enrichment factors of Pb resulted in homogeneous columns, indicating that small variations in concentrations can be attributed to grain size differences, not presenting contaminated levels. From statistical results, the highest contribution on the first component was represented by a lithogenic source with the leaching of continental rocks. Lead content was notable in its high loadings in other components, which suggests atmospheric deposition. An increase in these components in subsurface samples from vertical profiles between 1935 and 1996 could represent a fingerprint of the consumption of leaded gasoline in Brazil between 1923 and 1989. Thus, statistical analysis of elemental data enabled to infer possible sources and pathways of Pb to the environment, without isotopic analysis.