Environmental Monitoring and Assessment最新文献

Access to safe drinking water and decent sanitation is a basic human right, yet most people in developing countries, particularly in Sub-Saharan Africa, lack access to them. The problem of inadequate clean water becomes complicated when biological and chemical agents contaminate available water sources. In Nigeria, bacterial water contamination is common; however, in recent literature, there is a lack of synthesis linking drinking water contamination with the emergence of antibiotic-resistant bacteria (ARB), including how the drinking water ecosystem may contribute to the spread of antibiotic resistance (AR). In addition, the microbiological mechanism that ensures the persistence of ARB in drinking water needs to be fully explored. Thus, this review integrates evidence on bacterial contamination and evaluates the role of drinking water in the dissemination of AR in Nigeria, including the contributions of poor sanitation, industrial effluents, abattoir operations, leachates from dumpsites, agricultural practices, and runoff from farm fields to the bacteriological quality of surface and underground water, and their consequences on human health. Also expanded are the processes leading to the emergence of ARB in water contaminated by sewage from domestic and pharmaceutical sources. Anthropogenic water contamination results in the emergence of ARB carrying transmissible antibiotic resistance genes (ARGs) in drinking water, thus highlighting the need to eliminate bacterial contamination of drinking water sources to protect public health and ensure the sustainability of water resources. Integrating surveillance for AR in environmental and treated water into the national antimicrobial resistance surveillance network is recommended to control the spread and reduce the burden of waterborne antibiotic-resistant bacteria in Nigeria.

Recently, Mahreen et al. (2025) have carried out a baseline survey of microplastic (MP) contamination in the Indian coastal agricultural soils. They also found MPs on all samples, as well as toxic heavy metals (Fe, Cd, As) that were attached to MP surfaces (Mahreen et al., 2025). The presence of multiple heavy metals on MPs, as indicated by the authors, was interpreted as an indication of a complex scenario of pollution whose consequences might have adverse effects on the health of the soil, crop productivity, and soil biota. This is a valuable addition to the knowledge of MP pollution in the terrestrial environment. Nevertheless, we would like to highlight an important methodological weakness that could influence the interpretation of such findings: the lack of a contextual background, contamination, and soil chemistry. In the absence of this information, one cannot tell whether the identified heavy metals on MPs identify a truly novel risk pathway or merely indicate co-existing pollution that is already in the soil environment.

This study provides a comprehensive spatial and seasonal assessment of environmental quality in the Porto Novi coastal zone (Boka Kotorska Bay, Adriatic Sea), focusing on the distribution of phytoplankton, nutrients, and fecal bacteria in water and sediment. Sampling was conducted at six stations over four seasons during 2019–2020. The PN1 station consistently showed the highest levels of fecal bacteria, particularly in spring, while sediments acted as a reservoir for fecal bacteria, especially at PN1 and PN3 during spring and autumn. Diatoms were the dominant phytoplankton assemblage with maximum abundance in spring and summer, while dinoflagellates reached the highest abundance in autumn. Coccolithophores had bimodal growth peaks: in spring and autumn, especially in lower layers. Total phytoplankton abundance bloom was the most intensive in summer, at the PN1 location. The Integrated Parameter Response (IPR) index indicated elevated ecological pressure in summer and autumn, while PCA analysis separated PN1, PN2, and PN3 locations as well as spring and winter seasons. Physicochemical parameters (except nitrite) and fecal bacteria remain within threshold limits, but a higher prevalence of fecal bacteria in sediment, intense phytoplankton blooms reaching up to 10⁵ cells L⁻¹, the presence of potentially toxic phytoplankton species, and seasonal nutrient enrichment patterns, suggest latent pollution and pressure from land-based sources. This research highlights the need for further seasonal monitoring and serves as a baseline to make strategies for decision-makers.

Freshwater turtles are ecologically vital yet threatened by habitat loss. This study in the transboundary Gandak River, India, investigated how hydrological and physicochemical factors influence the distribution, encounter rates, and growth of two turtle species, Lissemys punctata and Pangshura tecta. A seasonal survey monitored environmental variables and turtles across four sites. Morphometric data were used to establish length–weight relationships (LWR) and compute condition factors. Principal Component Analysis (PCA) identified key environmental gradients correlated with species encounter rates. The study recorded 69 individuals (L. punctata, n = 43; P. tecta, n = 26). Clear spatial habitat partitioning was observed: P. tecta was exclusively found in smaller, pebble-dominated tributaries, whereas L. punctata was present in all sites but encountered more often in the main river channel. Turtle encounter rates for both species peaked during winter, with a significant positive correlation (r = 0.482, p = 0.017) with PCA Component 2, which represented stable, clear-water winter conditions (high transparency, high pH, low temperature/flow). No turtles were captured or observed during the peak monsoon, a period of high hydrological disturbance. The LWR revealed negative allometric growth in both species (L. punctata: b = 2.608; P. tecta: b = 2.392). Condition factors (Kn ≈ 1.0) indicated body weights consistent with predicted values in this habitat. These findings underscore the importance of preserving habitat heterogeneity and natural flow regimes for the conservation of these turtles in the biodiverse, transboundary Gandak River system.

Wheat is a major staple crop worldwide, making the assessment of heavy metal contamination a critical concern for food safety and public health. This study presents a nationwide evaluation of cadmium (Cd) and lead (Pb) concentrations in wheat grains and corresponding agricultural soils across five major agroecological zones in Iran. A total of 2016 wheat grain samples and 690 soil samples were collected from representative wheat-growing regions during 2018–2021 and analyzed using validated analytical methods. The results revealed that the mean concentrations of Cd (0.011 mg/kg) and Pb (0.032 mg/kg) in wheat grains were below the maximum permissible limits set by national and international standards. However, spatial analysis identified localized contamination hotspots, particularly in northern and western provinces, where metal concentrations approached regulatory thresholds. Soil pollution indices generally indicated low contamination levels and low ecological risk at the national scale, with slight enrichment observed in limited areas. Soil–grain relationships were weak but statistically significant, suggesting that Cd and Pb uptake is influenced by soil pH, organic matter content, wheat cultivar, and agricultural management practices. The predominantly alkaline nature of soils in the studied regions appears to reduce Cd and Pb bioavailability and imit their transfer into wheat grains. Health risk assessment based on estimated dietary intake revealed Hazard Quotient values (HQ < 1) for both metals, indicating no significant non-carcinogenic risk associated with wheat consumption under average dietary scenarios. Overall, although current contamination levels do not pose a significant public health risk, the findings highlight the need for continued regional monitoring to sustain safe wheat production and prevent future accumulation.

Few studies have examined the antimicrobial resistance profiles and phylogenetic diversity of bacteria in Latin American beaches. The aim of this study is to provide nationwide data on Escherichia coli from recreational beaches along the Costa Rican coasts, contributing to the understanding of this knowledge gap. Thirty-nine strains were recovered, one per sampled site, and tested for susceptibility to eleven antibiotics using the disk diffusion method. PCR was used to detect sulfonamide resistance genes (sul1, sul2) and the class 1 integron gene (intI1), while phylogenetic classification was conducted following the Clermont multiplex protocol. Resistance to at least one antibiotic was observed in 84.6% of isolates, with ampicillin (58.97%) and cefazolin (51.28%) showing the highest resistance rates. Multidrug resistance was found in 20.5% of strains, and 33% had MAR indices exceeding 0.2, suggesting contamination from high-risk sources. Phylogroup B1 predominated (51.3%), indicating widespread environmental or animal-associated contamination, although human-related groups (D_E and B2) were also present. The integrase gene intI1 was detected in 66.7% of isolates, suggesting potential for horizontal gene transfer. These results confirm the presence of resistant E. coli strains, including multidrug-resistant and human-associated phylogroups, in Costa Rican coastal waters. They underscore the urgency of integrating AMR surveillance into national water quality monitoring systems and improving wastewater treatment infrastructure to reduce the spread of resistant bacteria in recreational environments.

This study investigates the spatio-temporal variation of elemental (Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, Pb, Zn) and anionic (Cl⁻, SO₄⁻², F⁻, NO₃⁻) concentrations across pre-burning, post-burning, and regeneration phases of shifting cultivation in West Garo Hills District of Meghalaya, Northeast India. Samples were collected from six shifting cultivation sites across three phases. Elemental concentrations were analysed using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) and anions via Ion Chromatography (IC) following US EPA 3051A and US EPA 300 protocols respectively. Statistical test revealed significant phase wise variations. Post-burning ash deposition significantly elevated Ca, Mg, Fe, Li, and Zn levels, while Cd, Ni, Pb, and Ba decreased significantly due to leaching and volatilisation. Pollution indices revealed severe geogenic contamination, with Cd showing extreme enrichment and contributing 94% to the Ecological Risk Index (ERI > 320) across all phases. Pb and Li also exhibited high enrichment. The Geoaccumulation index (I_geo), Nemerow Pollution Index (NPI > 3), and Contamination Factor (CF), collectively indicated significant contamination, predominantly derived from lithogenic sources. Among anions, SO₄²⁻ concentrations increased significantly after burning (375.67 mg/kg) and decreased during regeneration (38.83 mg/kg). NO₃⁻ decreased from 268.67 mg/kg in the pre-burning phase to 119.56 mg/kg post-burning, followed by a significant increase during regeneration (475.50 mg/kg), likely due to microbial recovery. Chloride and F⁻ concentrations decreased during regeneration, indicating leaching losses. Correlation and multivariate analyses (PCA, HCA) suggested that elemental variations were primarily influenced by parent rock weathering with minimal anthropogenic input. Overall, the findings highlight the transient nutrient enrichment after burning and the need for sustainable land management and mineralogical assessment of parent materials.

This study aims to determine the spatial distribution and potential pollution levels of heavy metals (Cr, Mn, Ni, Cu, Zn, and Pb) in soils between Seydişehir and Beyşehir in Konya Province, Türkiye. A total of 20 soil samples were analyzed for heavy metal contents along with physicochemical parameters such as pH, organic matter, and electrical conductivity. Soil pH values ranged from 6.29 to 7.63, indicating generally neutral conditions. Ni and Pb exhibited the highest accumulation tendencies on a regional scale, while Cr and Mn showed localized enrichments in certain samples. Spatial distribution analyses revealed a heterogeneous pattern of heavy metal concentrations, reflecting the influence of localized environmental pressures. The Pollution Index ((P_N)) values indicated that most samples are under moderate environmental stress, with samples 11, 17, 18, and 20 showing a higher pollution potential. The strong correlation observed between Cr and Ni (r = 0.79) suggests that these elements may originate from common anthropogenic sources. This research provides the first comprehensive baseline dataset for the region’s soils and offers valuable insights for future monitoring, source identification, and sustainable land management strategies.