Indicators Of Contamination Research Articles

Assessment of Water Quality in a Public Supply Source: Combined With the General Index of Human Contamination

Objective: The aim of this study was to evaluate the water quality of the Miringuava River watershed through monitoring of chemical water quality parameters, assess the presence of Emerging Contaminants (EC) such as hormones and caffeine, and determine the General Index of Human Contamination (GIHC). Theoretical Framework: Watersheds located near urbanized areas play a crucial role in water resource management, especially when used for public supply. Due to land use and occupation, the natural dynamics of rivers, and reurbanization processes, monitoring water quality within a watershed is necessary (Pereira et al., 2021). Consequently, the social impact and effects on aquatic environments must be considered (Sekamane et al., 2023). Method: Two collections were conducted (C1 with 7 points and C2 with 16 points) upstream of the water intake station of SANEPAR to obtain water samples from the Miringuava River watershed. The methodology was defined in four stages: Definition of sampling points, sending water samples to the LEAQUA Laboratory – UTFPR, analysis of the data processed by the laboratory, and construction of the GIHC graphs. Results and Discussion: The results obtained revealed the presence of Emerging Contaminants in some water bodies in the region. Considering the hormone Estradiol (E2), which is an emerging contaminant, Ide et al., (2017) found a maximum value of 1420 ng L-1 in the Iguaçu River basin. In comparison, the values found in the Miringuava River basin were 23.14 ng L-1, indicating that the level of estradiol is considered low. Research Implications: The practical and theoretical implications of this research indicate that there are already signs of minor contamination in the water bodies of the Miringuava River basin. Such implications demonstrate the need for monitoring in the region. Originality/Value: This study contributes to the understanding and confirmation of the presence of emerging contaminants in the Miringuava River basin, which will be used for public supply. By evaluating chemical parameters and the General Index of Human Contamination, it provides important information for water quality management in the region.

Impact of a lagoon with high anthropic activity on a World Heritage Site.

The Ichkeul-Bizerte Lagoon Complex (IBLC), a critical ecosystem for local biodiversity, faces a pressing threat due to climate change and severe pollution. Despite past conservation efforts, pollution persists, particularly in the Bizerte Lagoon. This study investigated the impact of water dynamics and climatic conditions on heavy metal contamination in the IBLC's sediments. During the dry hydrological year of 2019/2020, 80 surface sediment samples were collected and analyzed for heavy metal concentrations using inductively coupled plasma. Sediment quality was first evaluated by comparing heavy metal concentrations against sediment quality guidelines established by NOAA. Additionally, contamination indices, including the contamination factor (CF), pollution load index (PLI), and geo-accumulation index (Igeo), were utilized to provide a more detailed assessment. Spatial and temporal variations in contamination were assessed, with seasonal variations mapped using the inverse distance weighting method. The findings revealed that El-Fouledh, the Menzel Jamil industrial area, and the Menzel Abderrahmane port are the primary pollution sources. The spatial distribution of pollution shows a decreasing gradient from the east (Bizerte Lagoon) to the west (Lake Ichkeul), with high levels of cadmium, lead, and zinc exceeding sediment quality guidelines and posing significant threats to this Ramsar-listed ecosystem. Spearman´s correlation coefficient highlighted the persistence of pollution across seasons, emphasizing the urgent need for comprehensive management strategies to mitigate pollution and preserve the IBLC's ecological integrity.

First record of microplastic contamination in adult endemic amazonian anuran species

The microplastics (MPs), due to their high dispersion and bioaccumulation rates, have been identified in various animal groups, such as anuran amphibians during both larval and adult stages. However, current studies on adult anuran amphibians focus on assessing only one exposure route, the digestive system, while other routes remain underestimated. Therefore, this present study aimed to evaluate the degree of contamination in the digestive, respiratory, and integumentary systems, in situ, of two endemic Amazonian adult anuran species (Physalaemus ephippifer and Boana multifasciata). From this, we identified and characterized microplastic particles for each exposure route, assessed the effects of morphometric measures on the total MP contamination level and in the gastrointestinal tract (GIT). Additionally, we determined different contamination indices and how they vary according to species and systems. Based on our data, the digestive and integumentary exposure routes showed the highest contamination levels for both species. Additionally, variations in MP contamination levels indicated that P. ephippifer had a higher level of MP contamination. Thus, this study provides the first evidence of microplastic exposure through respiratory and integumentary routes in adult anurans in situ, and it is the first to identify MP contamination in terrestrial biomonitors in the Amazon.

Environmental impact of lead in soybeans (Glycine max L.) marketed in the canton of Quevedo, Ecuador

The bioaccumulation of lead in soybean crops, originating in contaminated soils, represents a significant environmental problem and a risk to public health due to the inherent toxic metal. The objective of this study was to evaluate the environmental impact of lead in samples of soybeans (Glycine max L.) marketed in the canton of Quevedo, Ecuador. Grain samples were collected randomly, in triplicate, from four local markets during a period of [indicate period] and a control sample from a non-contaminated cultivation area. The samples were subjected to a preparation process that included drying, grinding, acid digestion with concentrated HNO₃ and HCl, and dilution. Lead determination was carried out by electrothermal atomization atomic absorption spectrometry (GFAAS). The calculation of the lead contamination index was performed using a standardized equation, contrasting the results obtained with the maximum allowable limits established by national (NTE INEN 452:2013) and international (Codex Alimentarius, European Union) regulations. The results evidenced an average concentration of lead in the soybean samples of 1.15 ± 0.13 mg.kg-1, significantly exceeding the maximum allowable limits. The calculated contamination index indicated a high level of contamination in the analyzed grains, which represents a risk to both the ecosystem and human health when consumed. These findings underscore the need to implement environmental and food management strategies to reduce lead contamination in soybean crops, thus ensuring food safety and public health protection.

Soil environmental monitoring of repurposed railway line operated for 75 years: case study in Northeast Poland

This study examines the environmental implications of repurposing former railway infrastructure into bicycle paths in northeastern Poland. While lauding the commendable initiative for offering eco-friendly transportation alternatives, the investigation emphasises the potential environmental and consequences linked to contaminated soils resulting from the former railway line, posing risks for both users and the environment. Topsoil samples (0-25cm) were collected from eight measurement points along the Szczytno - Biskupiec Reszelski railway line (Poland), at varying distances from the railway tracks (5-30m). Concentrations of specific Potentially Toxic Elements (PTEs), notably Ni, Zn, Pb, and Cd, were analysed in 48 topsoil samples. Furthermore, the soil contamination was assessed by contamination indices, single (Igeo, PI) and integrated (RI, (IPln, MERMQ). The study revealed variations in PTE concentrations, with the highest levels recorded at the fourth and seventh sampling sites (4:34.2-57.5mg/kg; 7:18.2-42.3mg/kg). These findings were consistently supported by the MERMQ and RI indices, emphasising the significant risks for the environment and increased soil toxicity. In light of the EU's proposed Soil Monitoring Law, the research emphasises the need for robust data collection, analysis, and contamination monitoring practices to facilitate informed decision-making and sustainable environmental management in repurposed transportation infrastructure.

Evaluation of spatial variation and nutritional status of environmental quality in the surface seawater from fishing harbours of Hainan island

To investigate the nutrient distribution characteristics and the eutrophication status of the main fishing ports in Hainan Province, this study analyzed the 2021 seawater quality indicators, including biochemical oxygen demand (BOD5), chemical oxygen demand (COD), chlorophyll a (Chl a), ammonia nitrogen (NH4-N), nitrite nitrogen (NO2-N), nitrate nitrogen (NO3-N), and soluble active phosphate (DIP). The single-factor contaminant index method was employed to evaluate the water quality, revealing that the levels of COD, BOD5, and DIP surpass the national seawater quality standards for Type IV. The eutrophication index (EI) of the different fishing ports ranges from 2.38 to 56.29, indicating a high level of eutrophication.

Spatiotemporal distribution and human health risks of potential toxic elements in the groundwater of the lower Tista Floodplain, Rangpur, Bangladesh

This study assessed the extent of potential toxic element (PTE) contamination and its associated health risks in groundwater from the Tista Floodplain, Rangpur, northern Bangladesh. A total of 130 groundwater samples (65 from the wet season and 65 from the dry season) were analyzed for six PTEs: As, Al, Cu, Mn, Cr, and B using Atomic Absorption Spectrophotometry (AAS) and VIS Spectrophotometry. The mean concentrations of PTEs followed a decreasing order of B > Mn > Cu > Al > As > Cr in the wet season and Mn > B > Al > Cu > As > Cr in the dry season. Metal evaluation index and degree of contamination indicated minor contamination, while the Nemerow pollution index showed moderate to severe contamination, especially in Nilphamari district. Contamination levels were higher in the dry season compared to the wet season. No individual PTEs posed non-carcinogenic health risks, but combined PTEs presented potential health threats, particularly to infants, with higher severity during the dry season. No dermal health risks were identified. Despite the relatively low contamination levels, monitoring policies for new and existing tubewells should be implemented to ensure sustainable groundwater management and long-term water quality.

Quantitative and qualitative analysis of bioaerosols emissions from the domestic eastern wastewater treatment plant, Alexandria, Egypt.

Bioaerosol studies showed that wastewater treatment plants (WWTPs) are a significant source of bioaerosol emissions. In this study, 170 samples of total bacteria, total coliform, and total fungi were collected from 10 sites within a domestic WWTP, Alexandria, Egypt, using the sedimentation technique. According to the Index of Microbial Air Contamination (IMA) classes, the total bacteria range was 108-5120 CFU/dm2/hour, and all samples were classified as "very poor" except one sample of an office, which was classified as "poor." The total coliform range was 0-565 CFU/dm2/hour, and 6 samples were classified as "very poor," while one sample was classified as "poor." The total fungi range was 0-209 CFU/dm2/hour, and 9 samples were classified as "very poor," while 4 samples were classified as "poor." After the conversion to CFU/m3, the counts of total bacteria, total coliforms, and total fungi were 897 - 42.7 × 103, 0-4.71 × 103, and 0-2.69 × 103 CFU/m3, respectively. Several identified bioaerosols have been reported before as a cause of human infections. They included Lysinibacillus fusiformis, Bacillus cereus, Alcaligenes faecalis, Klebsiella sp., Escherichia coli, Aspergillus spp., Penicillium spp., Rhizopus sp., Candida sp., and Rhodotorula sp. These results indicated an increased health risk to WWTP staff, which needs more attention and more efficient control measures.

Study of contaminated snow cover using remote sensing in the Eastern Himalayas of Arunachal Pradesh, India.

Snow is considered contaminated when any foreign materials are deposited/mixed with it, which can accelerate melting and significantly impact the snow cover's radiative balance. Such an enhanced melting rate results in a reduction in freshwater sources at the catchment level. In optical remote sensing, snow contamination is widely studied using a normalizing difference index called the snow contamination index. This is based on the finding that the impact of snow contamination diminishes with wavelength and is most noticeable in the visible spectrum (0.3-0.7μm). However, the study of snow contamination using optical remote sensing is hindered in the Himalayan terrain due to enduring cloud cover in the region. Synthetic Aperture Radar (SAR) data such as Sentinel-1 can be used to ensure all-weather monitoring of such areas. This study focuses on the SAR backscattering behavior at the C-band of clear and contaminated snow for March 2022 in a part of the Eastern Himalayas of Arunachal Pradesh, India. An attempt has been made to utilize Landsat-9 and Sentinel-1 to study the snow contamination. The SAR backscattering for snow conditions (clear/contaminated) is studied using thresholds obtained from the Landsat-9 snow cover map. The SCI and SAR backscattering statistical analysisshows a negative correlation (R2 > 0.6) at a95% confidence level. It is observed that in the microwave region of the C-band, contaminated snow has a comparatively higher backscattering value than clear snow. However, in the visible wavelength, the contaminated snow has a lower reflectance value than clean snow. Such behavior of the snowpack in the microwave region of the C-band is explained using the physical properties of the snowpack and thedominant scattering mechanism over the surface. The key findings of this study suggest that SAR backscattering is affected by snow contamination due to changes in the local incidence angle, snow wetness, and surface roughness. This research provides critical insight into snow contamination using microwave remote sensing, which can be the first step toward developing an index for radar observations.

Heavy Metals and Associated Risks of Wild Edible Mushrooms Consumption: Transfer Factor, Carcinogenic Risk, and Health Risk Index.

This research aims to investigate the heavy metals (i.e., Cd, Cr, Cu, Ni, and Pb) in the fruiting bodies of six indigenous wild edible mushrooms including Agaricus bisporus, Agaricus campestris, Armillaria mellea, Boletus edulis, Macrolepiota excoriate, and Macrolepiota procera, correlated with various factors, such as the growth substrate, the sampling site, the species and the morphological part (i.e., cap and stipe), and their possible toxicological implications. Heavy metal concentrations in mushroom (228 samples) and soil (114 samples) were determined by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). In the first part of the study, the soil contamination (index of geo-accumulation, contamination factor, and pollution loading index) and associated risks (chronic daily dose for three exposure pathways-ingestion, dermal, and inhalation; hazard quotient of non-cancer risks and the carcinogenic risks) were calculated, while the phytoremediation capacity of the mushrooms was determined. At the end of these investigations, it was concluded that M. procera accumulates more Cd and Cr (32.528% and 57.906%, respectively), M. excoriata accumulates Cu (24.802%), B. edulis accumulates Ni (22.694%), and A. mellea accumulates Pb (18.574%), in relation to the underlying soils. There were statistically significant differences between the stipe and cap (i.e., in the cap subsamples of M. procera, the accumulation factor for Cd was five times higher than in the stipe subsamples). The daily intake of toxic metals related to the consumption of these mushrooms with negative consequences on human health, especially for children (1.5 times higher than for adults), was determined as well.

Geographical disparities in cancer and occupational exposure to pesticides in a French-West Indies territory (2006–2019)

BackgroundIn the French West Indies, previous studies have reported findings on pesticide exposure and cancer incidence. A new exploratory geographical study, including a more sensitive soil contamination indicator, will provide more detailed information on the link between cancer incidence and organochlorine pesticide exposure. This study aims to investigate the association between incident cases of cancer and chlordecone soil contamination at an IRIS scale over the period 2006–2019 in Martinique.MethodsData on the 18 most frequent cancer sites were collected from the Martinique Population Based Cancer Registry. First, smoothed standardized incidence ratios at the level of the 141 IRIS were estimated, and then regression models including the smoothed standardized ratios were performed between cancer incidence and soil contamination index by sex and cancer site, using the Besag, York and Mollié models. Models were adjusted using an index of social deprivation. Results23,218 cancer cases were eligible for this study, with 21,920 cases included in the final analysis. Soil contamination was associated with a higher relative risk of cancer in women than in men, but no significant correlation was found for breast cancer in women or for prostate cancer. Lung, thyroid, stomach and rectal cancers in women, and melanoma in men, all increase significantly with the level of contamination. There was a significant increasing gradient in the incidence of multiple myeloma in men, from reference to highly contaminated areas.ConclusionIntegrating the latest available data on soil contamination and cancer incidence will extend on-going knowledge of chlordecone exposure and cancer incidence, which remains a major environmental concern in Martinique. Unexpectedly, our results show that the female population of Martinique is the most affected by chlordecone soil contamination.

Assessment of heavy metal contamination and health risk of lotus root in major producing areas of China

AbstractLotus root is a popular vegetable known for its nutritional value and unique taste. However, it can be susceptible to heavy metal contamination, which has raised concerns about its safety for consumption. This study aimed to analyse the extent of heavy metal contamination in lotus roots and assess the potential health risks associated with their consumption. The results showed that all measured heavy metal concentrations were below the maximum allowable limits, with contamination indices for all metals across nine provinces remaining below 1.0, classifying the lotus roots as “safe” for consumption. Non-carcinogenic risk assessment using the THQ showed values below 1.0 for all heavy metals in both adults and children, indicating negligible health risks. The HI was calculated as 0.107 for adults and 0.126 for children, with arsenic contributing significantly to these values at 47.76% for adults and 39.55% for children. The carcinogenic risk assessment revealed Carcinogenic Risk (CR) values of 8.37 × 10−8 for Pb, 2.04 × 10−5 for Cr, and 2.30 × 10−5 for As in adults, and 9.86 × 10−8 for Pb, 2.40 × 10−5 for Cr, and 2.71 × 10−5 for As in children. All CR values were within the acceptable range, indicating no apparent carcinogenic effects from lotus root consumption at current intake levels. However, it was noted that increased consumption could elevate risks associated with As, with limits of 174 and 93 g for adults and children, respectively, to maintain safety.

Exploring environmental risk in soils: Leveraging open data for non-sampling assessment?

Soil contamination by heavy metals (HM) is a critical area of research. Traditional methods involving sample collection and lab analysis are effective but costly and time-consuming. This study explores whether geostatistical analysis with GIS and open data can provide a faster, more precise, and cost-effective alternative for HM contamination assessment without extensive sampling. Concentrations of nine HMs (Cu, Pb, Ni, Co, Mn, As, Cd, Sb, Cr) were analysed from 498 soil samples collected in two mining areas in Portugal: the Panasqueira and Aljustrel mines. Corresponding data were extracted from the Lucas TOPSOIL 1km raster maps. Several contamination indices, Contamination Factor (Cf), Modified Contamination Degree (mCd), Geoaccumulation Index (Igeo), Nemerow Pollution Index (Pn), Potential Ecological Risk Index (PERI), and Pollution Load Index (PLI) were calculated for both datasets. A confusion matrix was used to evaluate the percentage of correct classifications, while a concordance analysis assessed the alignment of accurately classified points between the two data sources. In the soil samples, very high contamination levels for As were observed in 42% of the samples, according to the Cf, with high levels for Sb found in approximately 30% of the samples. The mCd revealed that approximately 11% of soil samples exhibited very high levels of contamination, while the Pn indicated that 78.9% of the soil samples fell within the seriously polluted domain. Similar contamination trends were observed for the other indices. In contrast, the results for the LUCAS points showed significant discrepancies. No high contamination levels were found for any metal. The misclassification rates for mCd, Pn, PERI, and PLI were 84.25%, 97.55%, 95%, and 82%, respectively, when compared to the field data. This study concludes that while open data raster maps offer rapid overviews, they fall short of providing the detailed precision required for reliable contamination assessments. The significant misclassification rates observed highlight the limitations of relying solely on these tools for critical environmental decisions. Consequently, traditional sampling and laboratory analysis remain indispensable for accurate risk assessments of HM contamination, ensuring a more reliable foundation for decision-making and environmental management.

Deteksi Bakteri Patogen Pada Daging Ayam Broiler Sebagai Skrining Foodborne Diseases Di Kabupaten Jember

Chicken meat is a source of animal protein that is very popular because of its high nutritional value, easy to obtain and cheap. However, as production increases, certain drugs and feed additives become essential for disease prevention, treatment, and growth promotion. The negative effect of using antimicrobial drugs is that they accumulate in animal tissues as residues and eventually become part of the food pyramid, subsequently impacting human health.A total of 45 broiler chickens were purchased from broiler meat sellers in 9 traditional markets in Jember. We took five broiler chicken meat randomly from each market. Samples have identified the type of contaminant bacteria using Salmonella Chromogenic Agar and Mannitol Salt Agar. The results of this study showed that broiler chicken meat samples were contaminated with E. coli (45/45 (100%)), Staphylococcus aureus (43/45 (95.56%)), Salmonella spp. (38/45 (84.44%)) and Proteus spp. (14/45 (33.33%)). All broiler meat samples purchased at the Jember traditional market were contaminated with at least 1 type of bacteria, namely E. coli. The index of bacterial contamination is between 0.25 – 1. The most common contamination patterns are S. aureus, E. coli and Salmonella spp., with a bacterial contamination index of 0.75.

Particle induced x-ray emission (pixe) assisted technique in the evaluation of potential ecological risks of heavy metals in surface sediments of Oba-Ile River, Ifelodun Local Government Area, Osun-State, Nigeria

The seasonal evaluation of trace elements in the surface sediments collected from Oba-Ile River, using Particle Induced X-Ray Emission (PIXE) Spectroscopy had been carried out. This was done so as to provide information about the pollution status of the river during the rainy and dry seasons. The samples were subjected to trace metal profiling using a 2.5 Mev proton available at the Ion Beam Analysis (IBA)/accelerator laboratory, Centre for Energy Research and Development (CERD), Obafemi Awolowo University, Ile-Ife. The facility is centered on a NEC 5SDH 1.7 MV Pelletron accelerator, equipped to provide proton and helium ions. A multi-elemental estuarine sediments referenced material (SRM 1646a purchased from NIST) was used for the determination of H-value which was subsequently used for analyzing the samples and assured the accuracy of the experimental procedure. The order of abundance of the 16 elements identified was Si > Fe >Al >K > Ca >Ti > Na > Mg > Zr > Mn > Sr > V > Cr > Zn > Pb > Cu. The contamination factor indicated that the metals presented a low contamination factor (LCf) to moderate contamination factor (MCf) except for Fe and Zr which presented a considerable contamination (CCf) and a very high contamination factor (VHCf) respectively. Other contamination indices indicated that Fe had either a moderate enrichment (ME) factor or a significant enrichment (SE) factor, thereby suggesting that Oba-Ile River sediment was particularly enriched in Fe

Geochemical assessments and human health risk evaluations of selected farm soils within the Abuja metropolis, North-central, Nigeria

Toxin accumulations in agricultural soils decreases the crop quality and productivity, and threatens the safety of foods, which could cause adverse human health effects. This study assessed the risks associated with potential toxins in the agricultural soils obtained from Lugbe and Jikwoyi in Abuja, Nigeria. An analytical technique for absorption spectrophotometry was adopted, and human health risks were evaluated. Twenty soil samples were collected from two farmlands, and two control samples were taken on unpolluted sites at depths 5-20 cm from the surface at the average suspension of plant roots where the soil holds most plant nutrients and water at a space interval of 5 m. The soils generally had low mean concentrations of Ca, Cu, Zn, Mn, Fe, and Co and moderately high mean concentrations of F, Ni, Pb, Cr, and Mo. The pattern of the pollutants reflected that the pollutants were majorly from anthropogenic activities, such as long-term fertilizer applications and other agrochemicals. The contamination indices revealed reassuringly low to moderate pollution risks to humans. The overall pollution loads suggested that the samples were largely unpolluted. The non-carcinogenic and carcinogenic health risks were within the safety limits for inhalation, dermal, and ingestion, which pose no significant risk to children and adults living in the vicinities of the farmlands. The cancer risks for inhalation were higher than dermal and ingestion, with Cr showing the highest values. The samples were slightly contaminated with potentially toxic metals, which could lead to increased phyto-accumulations, soil pollution, and groundwater contamination.

Spatial distribution of heavy metal contamination and risk indices of surface sediments in high-altitude lakes.

Lake ecosystems in northern Pakistan are the most critical resources that maintain and regulate water flow for downstream agricultural, domestic, industrial, and ecological processes. One consequence of these processes is that ecosystems deposit heavy metals (HMs), where lake stagnant conditions result in high vulnerability of water resources. For this purpose, the present study examined HMs such as cadmium (Cd), chromium (Cr), cobalt (Co), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) concentrations in high-altitude lakes (HAL) sediments of Mansehra district, northern Pakistan. Sediment samples were collected from the five HAL. This study used HM concentrations in lake sediments for the pollution factors such as contamination factor (Cf), pollution load index (PLI), sediment pollution index (SPI), ecological risk assessment (ERA), and risk index (RI). Among HMs, Fe showed the uppermost levels of 1410mg/kg in lake sediment, while Cd with lowermost levels of 1.05mg/kg. Results revealed that most HM concentrations in HAL sediments were within the threshold of sediments quality guidelines (SQGs), except for Cd. Among lakes, the sediments of Siri Lake showed higher contamination of HMs than others. Siri Lake sediments also showed higher Cf, PLI, ERA, and RI values than others. The majority of HMs in HAL sediments showed no contamination, except for Cd (considerable) and Pb (moderate) levels to the exposed aquatic ecosystem. This study revealed that 95% of sediment samples in HAL were noted low to medium-level risks to the exposed aquatic communities. Statistical and geospatial analyses revealed that geogenic sources of contamination are a significant contributor to HM contamination of HAL sediments compared to others.

Geographic Information System and Contamination Indices for Environmental Risk Assessment of Landfill Disposal Sites in Central Saudi Arabia

Landfills pollute air, soil, and surface and groundwater worldwide. The present work aims to assess the environmental risks of three landfills in southern Riyadh using GIS, soil quality guidelines, and contamination indices. GIS tools indicated an increase in the area of the landfill sites with time. The concentration of heavy metals (HMs) in the investigated landfills had the following descending order: Fe (11,532 mg/kg) ˃ Al (5405 mg/kg) ˃ Pb (561.7 mg/kg) ˃ Zn (356.8 mg/kg) ˃ Mn (165 mg/kg) ˃ Cr (74.8 mg/kg) ˃ Cu (42.7 mg/kg) ˃ Ni (22.4 mg/kg) ˃ V (21.8 mg/kg) ˃ As (5.16 mg/kg) ˃ Co (4.08 mg/kg). The highest values of Al, As, Co, Ni, Pb, V, and Zn were recorded from Al Kharj road landfill (RL3). However, the average values of all HMs were lower than those from most worldwide soils and backgrounds, except for Zn, Cu, Cr, and Pb. Results of enrichment factor and statistical analysis indicated deficiency to minimal enrichment and geogenic sources for Al, Co, Mn, and V, while those of As, Cr, Pb, Zn, and Cu showed EF ˃ 2, which might be indicative of anthropogenic activities, especially in RL3. Additionally, very high contamination and a high effects range—median were reported in individual samples, especially for Pb, As, and Zn, indicating frequent adverse effects for these HMs. The difference in contamination for the HMs in the studied landfill sites might be attributed to the difference in the magnitude of input for each metal into the landfill site and/or the difference in the removal rate of each metal from it.

Long-term contamination by non-native fish assemblages in a Neotropical floodplain.

Biological invasions are a major threat to biodiversity in species-rich regions. Therefore, it is important to understand mechanisms behind the long-term establishment of non-native fish species in aquatic environments in the Neotropical region. Here, we associated fish biomass, species richness, and the proportion of non-native species (contamination and Kempton's indices) to quantify the non-native pressure over fish biodiversity in lakes and rivers of the Parana River floodplain, seasonally, from 2000 to 2017. We divided species into native and non-native assemblages sampled in spatio-temporal gradients. Temporal trends were examined using linear regressions and generalised additive models. Fish biomass in gillnets increased for both native and non-native fish species, but their Kempton indices were inversely correlated. Extinction of native species occurred locally with biotic differentiation of non-native species in lakes, rivers, and ecosystem contamination. A constant increase in fish biomass resulted in overwhelming biodiversity of non-natives at the end of the time series evaluated. Native biotic resistance to introductions was not detected in deterministic trends. The observed patterns were consistent with previous studies showing native biotic homogenisation and extinction of species in response to biological invasions, landscape fragmentation, and riverine impoundments. Increases in abundance and species richness of non-native fish were the biodiversity drivers that resulted in non-native species outweighing native species in the Parana floodplain.

Geoenvironmental and Health Indices to Assess the Hazardousness of Heavy Metals in Urban Dust in Schoolyards in Murcia, Spain.

The aim of this study was to evaluate the possible contamination of urban dust in the schoolyards of 27 schools in an urban area of the city of Murcia (SE Spain). The color and degree of magnetism, as well as the heavy metal content (Cd, Cu, Cr, Ni, Pb, and Zn), were determined to establish the absence or the degree of contamination, if present, using environmental and health indices. It was established that the concentrations of heavy metals in the dust samples followed the order Zn (454 mg kg-1) > Cu (77 mg kg-1) > Cr (68 mg kg-1) > Pb (56 mg kg-1) > Ni (19 mg kg-1) > Cd (0.4 mg kg-1). Dark-colored dust showed the highest concentrations of contaminants associated with medium or high magnetism. An analysis of the magnetic and non-magnetic fractions indicated the highest concentrations of all heavy metals in the magnetic fraction. According to the geoenvironmental indices used, the ecological risk in these schoolyards is moderate overall. Based on the health indices, ingestion is the main route of entry of dust particles into the body, which poses the main health risk for adults and children for all heavy metals. Regarding the hazard index (HI) for all elements and the cancer risk (CR) for children and adults, the results indicate that there is no health risk.