Integrated assessment of cadmium (Cd) and lead (Pb) contamination: bioaccumulation in the river snail Filopaludina martensi (Frauenfeld, 1864), sediment, and water from the Mae Kha Canal, Chiang Mai Province, Thailand.

Exponential industrialization and anthropogenic activities have resulted in water contamination by various heavy metals in Kanpur city, India. Heavy metal pollution, an issue of great concern, is not only affecting river water, but contamination of groundwater is creating health issues and worries. In the present investigation, blood samples were collected from selected volunteers, water and sediment samples from four sites of river Ganga and drinking groundwater samples from 23 locations of Kanpur city. Heavy metals analysis in river water, sediment, and human blood, was done byinductively coupled plasma optical emission spectroscopy (ICP-OES) and atomic absorption spectroscopy (AAS) was used for groundwater samples. Human blood showed a high concentration of arsenic (As) (66.6 ± 0.00 and 76.9 ± 0.01μg L-1 in males and female subjects, respectively) and thallium (Tl) (13.4 ± 0.004 and 16.6 ± 0.005μg L-1 in males and female subjects, respectively) with higher concentrations in females than males. Other heavy metals (Nickle, Beryllium, Cadmium, Cobalt, Chromium, Lithium, Molybdenum, Lead) were not observed in any of the tested human blood samples. However, in groundwater sampling, iron (Fe), copper (Cu), and arsenic (As) were detected, one sample had the presence of chromium (Cr), and two samples showed lead (Pb) contamination. River water [Cu (32-125μg L-1), Cr (19-725μg L-1), Cd (1-59μg L-1), Pb (37-163μg L-1), As (32-153μg L-1), Th (26.75μg L-1)] showed a high level of the heavy metals, as compared to reference values of BIS, CPCB (2016a), WHO, EPA and USEPA. River sediment [Cu (4168-34,470μg Kg-1), Cr (4040-145,650μg Kg-1), Cd (326-5340μg Kg-1), Pb (1840-19,350μg Kg-1), As (103-188μg Kg-1)] also showed high concentration when compared to reference values of USEPA and PASS. River site 4, with high Cr (725 μg L-1), also showed Cr levels (19.8 μg L-1) in the groundwater samples, indicating Cr contamination in groundwater while Pb was observed at groundwater samples close to two industrial sites. Drinking water might be the primary exposure pathway for As and Tl to enter the human body. The study recommends periodic monitoring of river water, sediment, groundwater, and human blood samples for contamination of heavy metals.

Traditional gold mining, in which mercury is still used to process the ore, is widespread in Indonesia. The objective of this study was to investigate the distribution and mobility of mercury in river sediments and water in Banyumas, Central Java. River sediment and water samples were collected from several places, using a systematic random method, and then analyzed in the laboratory. The results showed that the mining activities in the study area were the main source of the mercury in the river water and sediments. The mercury concentrations in river water and sediments were high relative to those found in other areas, perhaps because there have been mining activities in this area for a long time and mercury had accumulated in the sediments. The high percentage of bioavailable mercury in the river sediments suggests that the mercury in the river sediments was relatively mobile and had the potential to directly pollute the environment when released into the river water and taken up by aquatic organisms.

The article considers the chemical composition features and pollution levels of river waters and sediments in the Seversky Donets River basin. The river waters pollution degree has been assessed using the specific combinatorial index of water pollution, and the river sediments pollution level has been evaluated using the conventional total pollution index and the integral contamination index of river sediments proposed by the authors. In order to compare the chemical compositions of the studied media we have used the concentration coefficients of elements in river waters and sediments based on the corresponding clarks. The physical and chemical features of the elements which contents differ significantly in the studied media have been analyzed in detail: namely manganese, copper, nickel, and lead. Physical and geographical and other factors that influence the distribution of elements within the river water – river sediments system in the study area have also been considered. It has been revealed that the level river sediments pollution in the Seversky Donets River basin is determined by elevated contents of nickel and lead. These elements are transferred mainly in a suspended form. It is demonstrated that the river waters pollution level depends on a number of macro- and microcomponents, and manganese and copper compounds make a significant contribution. It is concluded that the discrepancy between the levels of river sediments contamination and the river water pollution in the Seversky Donets River basin is mainly caused by the self-purification processes in river sediments.

Lead contamination in sediments in the past 20 years: A challenge for China

Persistent, multi-sourced lead contamination in Central Europe since the Bronze Age recorded in the Füramoos peat bog, Germany

Rare earth element distributions in rivers and sediments from the Erdenet Cu–Mo mining area, Mongolia

A study on two adjacent small ephemeral river systems in the upper Tano River Basin in Brong Ahafo, Ghana; one impacted by ASGM and the other by a modern large gold mining (LSM), showed that impacts of mining on river sediment and water quality and quantity were reflected in the macroinvertebrate and microbial communities. This study investigated the impacts of ASGM on the ecology of the Surow River and that of a large-scale mining (LSM, the Ahafo mine) on the Subri River between February 2013 and April 2014 Macroinvertebrate communities responded to the shift in river water and sediment qualities, whilst microbial communities tended to respond to water quality only. Bioaccumulation and biomagnification of mercury were evident in fishes in the river system impacted by ASGM, although mercury was barely detected in river water and sediment. The study confirmed that impact assessment of ASGM or the modern LSM on rivers should not be limited to the physical and chemical properties of water and sediment, but also include its riverine biota.

Uranium series disequilibrium in river sediments and waters: the significance of anomalous activity ratios

Cadmium and lead contamination in japonica rice grains and its variation among the different locations in southeast China

This study investigated the lead (Pb) contamination levels in a military shooting range soil of Nowshera Cantonment, Pakistan. For this purpose, various soil samples were collected from the military shooting range and analyzed for Pb concentration using the atomic absorption spectrometry (Perkin Elmer 1100B, USA). Results demonstrated that soil Pb concentrations ranged from 1 to 193 mg/kg. Soil pollution index values revealed that 42% of sampling sites showed a higher level of pollution and exceeded the limits. The soil of the shooting range was classified into four types based on determined Pb concentration such as control/clean, agriculture soil threshold (50 mg/kg), this study means (62.5 mg/kg), and the highest level (193 mg/kg). The above four types of soils were used to evaluate the phytoremediation potential of indigenous plants like Chenopodium album L. and Cynodon dactylon L. in the greenhouse environment. Results showed that the highest level of Pb was accumulated in plant species exposed to the soil of maximum contamination. Moreover, among the studied plant species, the Cynodon dactylon L. did not exhibit any harmful effects with an increase in Pb contamination. Therefore, the studied plants could be used as a better remedial strategy in Pb-contaminated soils.

Based on garden cress significantly used for phytoremediation, the antioxidant system included antioxidant-phenolic compounds and antioxidant-enzymes of 6-day-garden cress sprouts (GCS) were assessed as potential bio-indicators for cadmium (Cd) and lead (Pb) contamination. Total phenolic and flavonoid contents of GCS germinated under Cd and Pb treatments (25–150 mg kg−1) gradually increased with increasing concentration of metals and peaked by 2.0, 2.6, and 2.5, 2.3 folds at 150 mg kg−1, respectively. By using DPPH, ABTS, and PMC antioxidant assays, the total antioxidant activity of phenolic compounds of GCS increased 6.1, 13.0, and 5.8-fold for Cd and 5.9, 14.6, and 8.2-fold for Pb at 150 mg kg−1, respectively. The antioxidant enzymes of GCS (POD, CAT, GR, and GST) were significantly activated in response to Cd and Pb stress, and two new electrophoretic POD bands were detected. GCS was absorbed 19.0% and 21.3% of Cd and Pb at 150 mg metal kg−1, respectively. In conclusion, the approaches of the antioxidant defense system of GSC could potentially be used as bio-indicator for monitoring Cd and Pb contamination in a short time of germination process.

Radiogenic and stable Sr isotopes constrain weathering processes in rapidly eroding Taiwan catchments

A method of determination of fluorescent whitening agents (FWA) in river waters and sediments by high performance liquid chromatography (HPLC) was studied.Six kinds of FWA could be separated according to following conditions; column : ODS SS-10-B 4mm i.d. X 250mm, mobile phase (a) 0.011 NaH2PO4 -acetonitrile (75 : 25v/v), flowrate : 1.0ml/ min. FWA in the column effluent were monitored with fluorescent detecter (Ex=358nm, Em =403nm).FWA in river waters were adsorbed on SEP PAC cartridge and eluted with methanol. FWA in river sediments were directly extracted by shaking with methanol successively three times. Each extract was evaporated to dryness and dissolved in the solution of water-acetonitrile (70 : 30v/ v) for HPLC.From river waters and sediments of the Sagami river, two types of FWA (FWA I and FWA II), the same as used in the detergents, could be detected. For the rapid quantitative analysis of FWA I and FWA II, it was found to be effective to use mobile phase (b) 0.1% tetraethyl ammonium perchrorate in water-acetonitrile (70 : 30v/v). Then peak heights were linear with FWA amounts in the range of 010ng for FWA I and 01ing for FWA II. By the proposed method, FWA in river waters and sediments of the Sagami river were determined as follows ; FWA I : 0.09-3.4μg/g in sediments, FWA II : 0.85-4.4, μg/l in river waters, 0.1410.7μ g/g in sediments.

Lead (Pb) contamination resulting from the Lapindo mudflow in Indonesia has generated long-lasting heavy metal stress in nearby agricultural soils, persisting for over 20 years. Microbial community responses to such environmental-geological contamination remain poorly characterized within the region. This study was designed as an exploratory investigation of the impact of Lead (Pb) contamination on bacterial diversity and community composition, in order to establish baseline ecological data for future large-scale bioremediation assessments. Soil samples were collected from three locations with differing Pb contamination levels: Location 1: Glagah Arum, Location 2: Polo Gunting, and Location 3: Pond epicenter-P025A. Physicochemical parameters were analyzed, and bacterial communities were characterized using Oxford Nanopore full-length 16S rRNA gene sequencing. Alpha-diversity metrics (Shannon, Simpson, and Chao1 indices) were computed from normalized operational taxonomic unit (OTU) data to assess microbial richness and evenness. Preliminary observations suggest that the physicochemical parameters are as follows: Location 1 (low, 2.85 mg/kg), Location 2 (moderate, 3.08 mg/kg), and Location 3 (high, 11.38 mg/kg). Diversity decreased by about 30–40% with increasing Pb concentration. Community composition appeared to shift progressively from Pseudomonadota dominance in low Pb soils to Bacillota and Thermodesulfobacteriota in moderately contaminated sites, and to Cyanobacteriota (Oscillatoriales) in highly contaminated soils. A resilient core microbiome of 425 taxa was detected across all sites. Redundancy analysis indicated Pb concentration as the dominant environmental filter, with soil organic matter and moisture providing secondary influences. This study provides an exploratory assessment of community composition under Pb contamination, excluding functional genes and an actual bioremediation assay, which may inform future bioremediation and ecological restoration.

This study investigates lead (Pb) contamination in wild animals in Japan. Pb is a known environmental toxin that can cause several issues in wildlife. Pb is still used in human society, and among Pb products, ammunition is reported to harm human and animal health. In Japan, few instances of Pb contamination in wild animals have been reported outside Hokkaido. Possible reasons for this include the absence of Pb contamination and insufficient investigation. This study aimed to understand the current state of Pb contamination in Japan and clarify the extent of Pb contamination related to ammunition. Blood lead concentrations (BLLs) were measured in wild birds and mammals from 25 municipalities, and an analysis was conducted based on ammunition-related factors. More than half of the avian and mammalian taxonomic groups were found to exhibit Pb contamination from environmental sources. Overall, this study suggests that Pb contamination is also present in wild birds and mammals living outside Hokkaido, Japan, and highlights the risks of mass mortality during infectious disease outbreaks as well as the potential health hazards of Pb exposure upon their consumption by humans. The results of this study highlight the importance of monitoring Pb contamination, particularly in hunting areas of Japan. Further, it indicates the need to reconsider the use of Pb-based ammunition for protecting the health and welfare of both humans and wildlife.