Micro/nano-plastics (MNPs) have been found within many environments and organisms including humans, making them a significant and growing concern. Initial research into the potential detrimental effects these MNPs both from acute and chronic exposure has been ongoing but still requires substantially more data to clarify. This research presents the response of nano-polystyrene (NPS) on Raphidocelis subcapitata, a freshwater alga, under an existing acute toxicity test along with additional analytical techniques to try identifying possible sources of toxicity. R. subcapitata cells were exposed for 72 h to a concentration range of 0-100 mg/l NPS. Growth Inhibition (GI) testing showed the R. subcapitata demonstrated statistically distinct reductions in growth over 72 h at all NPS exposure concentrations while not suffering culture collapse. By the 100 mg/l NPS exposure the R. subcapitata has suffered almost a 33.7% reduction in cell concentration after 72 h compared to control samples. Confocal imaging showed the NPS wasn't permeating into the algal plasma membrane or individual organelles but agglomerated onto the algal cell wall. The agglomeration was irregular but increased in total surface area covered as NPS concentration increases. UV-Vis fluorimetry testing produced a linear response of emission intensities to algae exposed to the 0-100 mg/l range of NPS. However, comparisons of emission intensity values of algae exposed to NPS to emission intensities of pure NPS at identical concentrations showed consistent intensity reduction. This response further indicated NPS agglomerating within the media and onto the alga cells seen from confocal imaging. Finally, Raman spectroscopy on R. subcapitata attempted to distinguish the key 1001 cm^-1 peak or other crucial identifier peaks of polystyrene from overall Raman spectra. This was not successful as emissions from algal component (e.g. phenylaniline) completely suppressed the signal region.

The present study employs a data review on the presence and aggregation of oxytetracycline (OTC) and resistance (AMR) bacteria in wastewater treatment plants (WWTPs), and the distribution of the contaminated effluent with the aid of shallow and deep ocean currents. The study aims to determine the fate of OTC and AMR bacteria in seafood, and demonstrate a relationship between AMR levels and human health. This review includes (1) OTC, (2) AMR bacteria, (3) heavy metals in aquatic environments, and their relationship. Few publications describe OCT in surface waters. Although OTC and other tetracyclines were found in 10 countries in relatively low concentrations, the continuous water mass movement poses a contamination risk for mariculture and aquaculture. There are 10 locations showing AMR bacteria in treated and untreated hospital effluent. Special effort was made to define the geography distribution of OTC, AMR bacteria, and heavy metals detected in WWTPs to show the likely dissemination in an aquatic environment. The presence of OTC in surface waters in Asia, USA, and Europe can potentially impact seafood globally with the aid of ocean currents. Moreover, low concentrations of heavy metals exert environmental pressure and contribute to AMR dissemination. Recommended solutions are (1) quantitative analysis of OTC, heavy metals, and AMR bacteria to define their main sources; (2) employing effective technologies in urban and industrial wastewater treatment; and (3) selecting appropriate modelling from Global Ocean Observing System to predict the OTC, heavy metals, and AMR bacteria distribution.

The city of Dnipro, a prominent industrial hub in Ukraine, is recognized for its particularly its significant industrial development. This study focused on two prevalent plant species, Ambrosia artemisiifolia L. and Erigeron canadensis L., within the vicinity. Sampling was conducted at points located 12.02 km away from the emission sources associated with battery production and recycling plants in Dnipro. Analysis of heavy metal concentrations such as, Cr, Cu, Pb, and Zn was conducted using atomic emission spectrometry from the soil and plants tissues of Ambrosia artemisiifolia L. and Erigeron canadensis L. The translocation coefficient (TF) was calculated for both plant species. The results revealed that Cu and Zn exhibited the highest bioaccumulation in the examined plants, whereas Pb demonstrated the lowest. The order of metal uptake by both plants was determined as Cu > Zn > Cr > Pb. Significantly higher concentrations of these metals were observed in the two studied plants compared to the soil (Ftheor < Fexp, p < 0.05), suggesting the bioavailability of metals for these plants. The translocation coefficient (TF) represented the ratio of metal concentration in the shoot/the root. The TF value of Erigeron canadensis L. exceeded 1 for four metals. On the other hand, the TF value of Ambrosia artemisiifolia L. surpassed 1 for Cr, Cu, and Zn. Consequently, both species emerge as potential phytoremediators for soils contaminated with these studied metals.

This work aims to assess the bioavailability and bioaccumulation of Cr, Cu, Pb, and Zn in the soil–plant system (Erigeron canadensis L.) in the zone of anthropogenic impact in Dnipro city, a significant industrial and economic centre of Ukraine. Sampling was carried out at three locations at distances of 1.0 km, 5.5 km, and 12.02 km from the main emission sources associated with battery production and processing plants in Dnipro. The concentrations of heavy metals such as Cr, Cu, Pb, and Zn were analysed using atomic emission spectrometry from soil and parts of Erigeron canadensis L. The highest concentrations of elements in the soil, both for the mobile form and the total form, were determined to be 48.96 mg kg⁻¹ and 7830.0 mg kg⁻¹, respectively, for Pb in experimental plot 1. The general ranking of accumulation of elements in all experimental plots, both for the plant as a whole and for its parts, was as follows: Zn > Cu > Cr > Pb. Zn for plants was the most available heavy metal among all studied sites and had the highest metal content in the plant (339.58 mg kg⁻¹), plant uptake index (PUI-506.84), bioabsorption coefficient (BAC-314.9), and bioconcentration coefficient (BCF-191.94). According to the results of the study, it is possible to evaluate Erigeron canadensis L. as a hyperaccumulator of Zn, Cu, and Cr and recommend it for phytoextraction of soils contaminated with Zn, Cu, and Cr and phytostabilization of soils contaminated with Pb.

The presence of sub-micron-sized plastics in the environment has been increasing, with the possible risks of these particles remaining relatively unknown. In order to assess the toxicity of these particles, 100 nm diameter green fluorescent nano-polystyrene spheres (NPS) (20–60 mg/L) were exposed to zebra mussels (Dreissena polymorpha) to investigate the mortality, clearance rate and stress-related biomarker responses. D. polymorpha were collected and analysed with standard OECD toxicological tests and biomarker analysis to detect both physical and biochemical responses after exposure to NPS. The toxicity of the NPS to D. polymorpha was low, with 60 mg/L NPS causing a mortality rate of 11.1% at 96 h which was statistically significant compared to the 4.2% control. No statistical change could be found for the condition factor (k_c) of D. polymorpha after NPS exposure. Clearance rates in D. polymorpha using R. subcapitata algae showed NPS-exposed mussels had a reduction of filtering efficiency of up to 30.5%. Bioassay testing shows a mixed but undeniably negative response from the D. polymorpha to the NPS, notably a significant rise in DNA Strand Breaks (DSB) and Metallothionein (MT) responses for high NPS concentrations. Additionally, Lipid Peroxidation (LPO) and Ferric Reducing Antioxidant Power (FRAP) assay tests showed a significant increase in response from the higher (>40 mg/L) concentrations of NPS exposure. Although Glutathione S-Transferase (GST) assay showed no statistical change from the control for all NPS-exposed samples, an increase of 20% had occurred for 60 mg/L NPS. Overall, a minimal toxic response from D. polymorpha to the NPS exposure below 40 mg/L was seen. After 40 mg/L NPS, mussels presented more acute toxicity in terms of mortality, along with reduced algal clearance rates and anincrease in biomarker response. This study revealed a clear induction of oxidative stress and DSB in the digestive gland of zebra mussels following exposure to nano-polystyrene. While these findings provide valuable insights into the potential harmful effects of nanoplastics in freshwater bivalves, further studies are necessary to help understand the level of threat plastic pollution may pose to the health of freshwater ecosystems.

Peat soils, when drained and transformed for different land uses, can release pollutants such as nitrate and phosphate into nearby water bodies and ecosystems through ditch networks. However, there have been limited studies to ascertain the extent and impact of these nutrient releases under various peatland use types. A total of fifty-four water samples were collected between October 2021 and January 2022 from five industrial cutaway bogs, twenty-five grasslands, and twenty-four forest plantations. The water samples were subsequently examined for nitrate–nitrogen and phosphate–phosphorus using the HACH DR890 colorimeter. This study showed that the nitrate–nitrogen concentration of the discharge water ranged from 6.9 mg/L from forestry to 10.52 mg/L from grassland. The phosphate–phosphorus concentration ranged from 0.43 mg/L from forestry to 0.78 mg/L from grassland. The nitrate–nitrogen and phosphate–phosphorus concentrations in the drainage channel exhibited by the grassland and the cutover did not differ significantly (p > 0.05). Upon comparing the results obtained with the established safety limits set by the European Union (EU) and World Health Organization (WHO), it was observed that phosphate–phosphorus and nitrite–nitrogen concentration in the surface water (specifically, discharge water) exceeded the permissible threshold concentrations in surface water. The nutrient pollution index revealed that the discharge water from the ditch networks across the studied peatland use type was highly polluted, with a trend following the order of grassland > cutover > forestry. These results are in line with the broader issue of excessive nutrient inputs in freshwater ecosystems, which can lead to eutrophication. This study promotes sustainable water resources and peatland management practices by determining nitrate–nitrogen and phosphate–phosphorus concentrations in discharge water from ditch networks associated with different peatland use types: grassland, forestry, and cutover. This research emphasizes the critical need for sustainable peatland management to improve water quality in the river basin districts under the Water Framework Directive.