Bulletin of Environmental Contamination and Toxicology最新文献

The aim of this study was to evaluate the impact of different irrigation sources on the levels of potentially toxic metals (Cd, Cr, Fe and Mn) in the edibles of citrus fruits (Citrus sinensis and Citrus limetta). The samples of fruit, soil and water were collected from two locations (fresh water irrigated-FW I and sewage water irrigated-SW II) within the city of Sargodha. The samples utilized in the study for metal analysis were prepared utilizing the wet acid digestion method. Metal determination was performed using Atomic Absorption Spectrometry (AAS). The potentially toxic metal values in the citrus samples ranged from 0.010 to 0.063, 0.015 to 0.293, 6.691 to 11.342 and 0.366 to 0.667 mg/kg for Cd, Cr, Fe and Mn, respectively. Analysis of Citrus limetta and Citrus sinensis indicated that the highest concentration of Cr, Fe and Mn is observed at the sewage water irrigation site (SW-II), whilst the minimum levels of Cr, Fe and Mn were observed at the fresh water irrigation site (FW-I). The results show that the levels of these metals in soil and fruit samples meet the acceptable guidelines outlined by USEPA and WHO. It was found that the metal pollution constitutes a potential threat to human health due to the HRI values for Cd, Cr, and Fe being above 1, despite the DIM values being below 1. Regular monitoring of vegetables irrigated with wastewater is highly recommended in order to minimise health risks to individuals.

Pesticide transport in the environment is impacted by the kinetics of its adsorption onto soil. The adsorption kinetics of pyrimethanil was investigated in ten soil samples of varying physicochemical properties. The highest adsorption was in the soil having the maximum silt and CaCO₃ contents, pH and electrical conductance but the lowest amorphous Fe oxides and CaCl₂ extractable Mn. Pseudo-second order kinetics and intra-particle diffusion model best accounted the adsorption kinetics of pyrimethanil. The equilibrium adsorption estimated by pseudo-second order kinetics (q₀₂) was significantly and positively correlated with CaCl₂ extractable Cu content (r = 0.709) while rate coefficient (k₀₂) had a negative correlation with crystalline iron oxides content (r = -0.675). The intra-particle diffusion coefficient (k_i.d.) had inverse relationship with CaCl₂ extractable Mn content in soils (r = -0.689). FTIR spectra showed a significant interaction of pyrimethanil with micronutrient cations. Adsorption kinetic parameters of pyrimethanil could be successfully predicted by soil properties. The findings may help to evolve fungicide management decisions.

A collaborative assessment approach, including impact index of comprehensive quality (IICQ), food pollution index (FPI), and single factor pollution index (PI), was used to simultaneously select priority metal pollutants and assess metal contamination status in the plastic-shed soil (PSS)-vegetable system of the industrial towns situated in the Yangtze River Delta, China. Overall, significant Cr increment as well as Cd and Cu pollution in PSS existed, which was related to anthropogenic activities, especially industrial wastewater irrigation. The evaluation using PI and FPI demonstrated that priority metal pollutants were Cu and Cd in PSS while Cr and Cd in vegetables. Additionally, the estimation using IICQ method revealed that 23.3% and 13.3% of the sampling sites were sub-moderately and heavily contaminated by metals, respectively. These sites especially with heavy pollution need priority pollution management. These data will be beneficial to metal pollution control in PSS-vegetable system around industrial areas.

Cadmium (Cd) contamination of farmland soils leads to Cd accumulation in crops and reduced micronutrient uptake, posing grave risks to food safety. Herein, we investigated the enrichment and transportation patterns of Cd and trace elements in different parts of six wheat genotypes grown in weakly alkaline Cd-contaminated soils via pot experiments. The results revealed that the wheat grain variety with high Cd accumulation (Ningmai13) demonstrated a 1.94-fold increase compared to the variety with low accumulation (Yanong0428). The transfer factor of Cd from wheat straw to grain ranged from 0.319 to 0.761, while the transfer factor of Cd from root to straw ranged from 0.167 to 0.461. Furthermore, the concentrations of other metals in wheat grains followed the order of Zn > Mn > Fe > Cu. There was a significant positive correlation between Cd and Mn in grains, indicating a potential synergistic effect. Overall, this study provides valuable insights into the regulation of micronutrient intake to modulate Cd uptake in wheat.

Monitoring wildlife exposure to biological hazards is a critical component of the wildlife risk assessment. In this study 38 hair samples were collected from 8 different species from ten districts of Russian Far East and Siberia and analysed for the presence of organochlorine pesticides (OCP). 50% of the samples were contaminated with - p, p'-DDT, α-HCH and DDD. DDT was the main contaminant found in 13 sample at concentrations range of 14.3 to 369.5 pg/mg hair, mean 91.9 ± 89.7 pg/mg. α-HCH was detected in three samples with the concentrations range 29.9-180.2 pg/mg. The p, p'-DDD was found only in one hair sample of Siberian roe deer from Altai region at 52.6 pg/mg. The exposure level is depended on animals habitat location. The most contaminated region is Terney district which is in the proximity to the borders with China and North Korea where OCP are still in use.

Sanitary leachate from urban landfills is known to be contaminated with multi-metals and residual antibiotics. Current research edges on exploring the multi-metal and antibiotic sensitivity profile of four indigenous strains, "Brevibacillus spp. Leclercia spp. Pseudescherichia spp., and Brucella spp." isolated from the leachate of a sanitary landfill in a tropical region. Indigenous isolates were observed to be antibiotic-resistant and have high tolerance against eight of the ten tested metals except Cu & Co. It was observed that interaction with multi-metals in laboratory conditions significantly altered the cell morphology of bacterial strains, as depicted by Scanning Electron Microscope. Metal adsorption onto the microbial surface was deciphered through Electron Dispersive Spectrometer analysis and elemental mapping. Application of isolated strains into real-time leachate matrix exhibits a complete reduction of Ag and Zn and for other tested metals. Their response to these toxicants may facilitate their application in bioremediation-based treatment technologies for urban landfill leachate.

The COVID-19 pandemic's disruptions to human activities prompted serious environmental changes. Here, we assessed the variations in coastal water quality along the Caspian Sea, with a focus on the Iranian coastline, during the lockdown. Utilizing Chlorophyll-a data from MODIS-AQUA satellite from 2015 to 2023 and Singular Spectrum Analysis for temporal trends, we found a 22% Chlorophyll-a concentration decrease along the coast, from 3.2 to 2.5 mg/m³. Additionally, using a deep learning algorithm known as Long Short-Term Memory Networks, we found that, in the absence of lockdown, the Chlorophyll-a concentration would have been 20% higher during the 2020-2023 period. Furthermore, our spatial analysis revealed that 98% of areas experienced about 18% Chlorophyll-a decline. The identified improvement in coastal water quality presents significant opportunities for policymakers to enact regulations and make local administrative decisions aimed at curbing coastal water pollution, particularly in areas experiencing considerable anthropogenic stress.

To clarify gaseous elemental mercury (GEM) in suburban megacities in the Yangtze River Delta region, China, we observed GEM concentrations from December 2019 to November 2020 in Wujing town, a suburban area of Shanghai. The annual mean GEM concentration was 1.44 ± 0.88 ng m^-3. Compared with the historical monitoring data of GEM in Shanghai over the past 10 years, the concentration of GEM showed a decreasing trend. The monthly mean concentrations of GEM showed clear seasonal variation, with higher values in the spring and winter. In spring and winter, typical Hg pollution events were observed, which could be mostly associated with increased local anthropogenic activity and temperature inversion. The results of the correlation analysis of the daily mean GEM concentrations with the AQI and backward trajectory calculations indicate that mercury pollution at monitoring sites can be affected by local, regional and interregional influences.

Microplastics (MPs) pollution is a profound problem around the world yet it's study on the effect on zooplankton including copepods are very limited. The study was conducted between January 2021 and January 2022 in the Lower Meghna Estuary to investigate MPs ingestion in two different family of copepod: Calanoid and Cyclopoid. A method of acid digestion along with Scanning Electron Microscope (SEM) was used to identify MPs ingested by copepods from the conducted area. However, three types of MPs namely fiber, fragment and foam were extracted from this copepod biomass. Fibers represent highest (> 50%) of the ingested MPs from both group of copepod that exceed fragments and foams in all sampling stations. The overall ingestion rate of Calanoid was found higher (0.084 ± 0.002 particles/individual) compared to the Cyclopoid group (0.077 ± 0.001 particles/individual). The results of the study have effectively illustrated that copepod, obtained from multiple sampling sites within the Lower Meghna Estuary, display a propensity to ingest MPs and subsequently endangering the food security of seafood industry.

Lead poisoning, is currently recognized as a real public health problem, The WHO classifies lead as one of 10 chemicals of serious public health concern. In Algeria and North Africa, to date, no study on the evaluation of lead impregnation has been carried out at the national level. The main objective of this work is to assess the exposure of the general Algerian population to lead. A cross-sectional study was carried out over the entire Algerian national territory, on a population aged between 3 and 74 years old. The survey lasted three years, A questionnaire, a clinical examination and a blood sample were carried out for each individual. Generalized linear regression models were used to determine the factors influencing lead levels measured in blood samples. The study population, spread over 39 wilayas and 121 districts, consists of 3674 individuals. The mean lead levels were 28.27 μg/L, the median was 22.22 μg/L, and the 95th percentile was 73.83 μg/L, Blood lead levels were influenced differently by age, gender, wilaya of residence, dietary habits such as consumption of canned food and the way in which water is conserved for daily consumption. The use of kohl has been confirmed as a potential source of lead exposure. In Algeria, a blood lead value of 75 µg/L serves as the Reference Exposure Value, guiding public health responses and risk management strategies, Recommendations have been issued to reduce the blood lead levels of the general population in Algeria in terms of limitation of lead in the sources of exposure, installation of an effective health monitoring system.