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In light of the growing plastic waste problem worldwide, including in agriculture, this study focuses on the usefulness of both conventional, non-degradable plastics and environmentally friendly bioplastics in the agricultural sector. Although conventional plastic products are still essential in modern, even ecological agriculture, the increasing contamination by these materials, especially in a fragmented form, highlights the urgent need to search for alternative, easily biodegradable materials that could replace the non-degradable ones. According to the literature, polymers are widely used in agriculture for the preparation of agrochemicals (mostly fertilizers) with prolonged release. They also play a role as functional polymers against pests, serve as very useful super absorbents of water to improve crop health under drought conditions, and are commonly used as mulching films, membranes, mats, non-woven fabrics, protective nets, seed coatings, agrochemical packaging, or greenhouse coverings. This widespread application leads to the uncontrolled contamination of soil with disintegrated polymeric materials. Therefore, this study highlights the possible applications of bio-based materials as alternatives to conventional polyolefins or other environmentally persistent polymers. Bio-based polymers align with the strategy of innovative agricultural advancements, leading to more productive farming by reducing plastic contamination and adverse ecotoxicological impacts on aquatic and terrestrial organisms. On the other hand, advanced polymer membranes act as catching agents for agrochemicals, protecting against environmental intoxication. The global versatility of polymer applications in agriculture will not permit the elimination of already existing technologies involving polymers in the near future. However, in line with ecological trends in modern agriculture, more "green" polymers should be employed in this sector. Moreover, we highlight that more comprehensive legislative work on these aspects should be undertaken at the European Union level to guarantee environmental and climate protection. From the EU legislation point of view, the implementation of a unified, legally binding system on applications of bio-based, biodegradable, and compostable plastics should be a priority to be addressed. In this respect, the EU already demonstrates an initial action plan. Unfortunately, these are still projected directions for future EU policy, which require in-depth analysis. [ABSTRACT FROM AUTHOR]

The European Union's Green Deal concept prioritizes the installation of photovoltaic and wind turbine systems, with the aim of significantly reducing greenhouse gas emissions and expanding the use of renewable energy. The inclusion of metals/metaloids such as Cd, Pb, Ni, and As to PV panels may be a matter of concern because they may provoke numerous negative environmental effects, especially after decommissioning. Although the release of Pb and Cd from solar panels is generally low, these releases may increase, posing long-term harm. Cd and Pb, if only released from solar panels, can enter the environment, including soil and water, posing a significant risk to human health and ecosystems. Cd, in particular, can have profound and lasting negative impacts on animals and humans, affecting cellular responses, enzyme operations, and immune system functionality. Pb exposure, in turn, can induce oxidative stress and neurotoxicity, disrupt ion regulatory pathways, and impair immune function. Despite efforts to reduce the release of toxic metals from PV panels, controlling their disposal and avoiding environmental contamination remains challenging. Discovering substitute materials for PV panel manufacture, implementing enhanced recycling procedures, performing bioremediation, and enforcing stronger restrictions are among the strategies to mitigate environmental concerns. [ABSTRACT FROM AUTHOR]

The United Nations World Drug Report published in 2022 alarmed that the global market of illicit drugs is steadily expanding in space and scale. Substances of abuse are usually perceived in the light of threats to human health and public security, while the environmental aspects of their use and subsequent emissions usually remain less explored. However, as with other human activities, drug production, trade, and consumption of drugs may leave their environmental mark. Therefore, this paper aims to review the occurrence of illicit drugs in surface waters and their bioaccumulation and toxicity in fish. Illicit drugs of different groups, i.e., psychostimulants (methamphetamines/amphetamines, cocaine, and its metabolite benzoylecgonine) and depressants (opioids: morphine, heroin, methadone, fentanyl), can reach the aquatic environment through wastewater discharge as they are often not entirely removed during wastewater treatment processes, resulting in their subsequent circulation in nanomolar concentrations, potentially affecting aquatic biota, including fish. Exposure to such xenobiotics can induce oxidative stress and dysfunction to mitochondrial and lysosomal function, distort locomotion activity by regulating the dopaminergic and glutamatergic systems, increase the predation risk, instigate neurological disorders, disbalance neurotransmission, and produce histopathological alterations in the brain and liver tissues, similar to those described in mammals. Hence, this drugs-related multidimensional harm to fish should be thoroughly investigated in line with environmental protection policies before it is too late. At the same time, selected fish species (e.g., Danio rerio, zebrafish) can be employed as models to study toxic and binge-like effects of psychoactive, illicit compounds. [ABSTRACT FROM AUTHOR]

Flow cytometry (FCM) is routinely used in medical and veterinary diagnostics although it is also widely applied in environmental studies, including phytoplankton investigations. Cyanobacteria are wide-spread photosynthetic microorganisms that attract attention due to their ecology and potential toxicity. Therefore, novel research tools are being applied in their investigation. This paper characterizes FCM as a technique that enables photopigments (chlorophylls and phycocyanin) expressed by cyanobacteria to be excited and their emission to be subsequently detected. This feature not only allows cells to be counted in a rapid manner but also enables a wide range of potential applications in ecological and biochemical studies. The main advantages of FCM, such as rapid, automatic and precise measurements requiring small sample volumes, are also discussed in this paper along with challenges including analyses of filamentous cyanobacteria and signal overlapping. It is expected that FCM will continue to be used in some fields of cyanobacterial studies.

The aim of the present work was to investigate the response of zebrafish to the effects of widely-used organophosphates roundup and chlorpyrifos and putative effectiveness of chlorella in terms of decreasing pesticides toxicity. Studied organophosphate pesticide roundup and chlorpyrifos in ecologically relevant concentrations, both individually and in a mixture, evoked the prominent suppression of catalase and total antioxidant capacity in the liver of Danio rerio which were consistent with higher levels of lipid peroxidation, protein carbonylation, and DNA strand break. Also, both roundup and chlorpyrifos provoked endocrine disorders registered as induction of vitellogenin and depletion of triiodothyronine as well as neurotoxicity appeared as inhibition of acetylcholinesterase after individual action or activation after combined action. The rate of apoptosis observed by caspase 3 activity was decreased, but in different manner depends on the exposure. The potency of toxicity followed the order: roundup > chlorpyrifos > roundup + chlorpyrifos (due to some kind of antagonistic action between chlorpyrifos and roundup in the binary mixture). Based on the results of CART analysis triiodothyronine, TBARS and caspase 3 were determined as the most significant indices for discrimination of the studied groups. The introduction of Chlorella vulgaris in the amount of about 100 thousand cells L-1 into the environment did not show a significant bioremediation effect on the harmful effect of studied pesticides for Danio rerio, which does not exclude the positive impact of algae on the functioning of the ecosystem as a whole and requires further comprehensive research.

The use of glyphosate-based Roundup and triazine herbicide Atrazine has increased markedly in last decades. Thus, it is important to evaluate toxic effects of these herbicides to non-targeted organisms such as zooplankton to understand their safety toward aquatic ecosystems. In the current study, we performed Daphnia toxicity tests based on lethality to identify LC50 that provides acute aquatic toxicity classification criteria. LC50 for Roundup exposure for 24 hours was found to be 0.022 mg/L and 48 hours - 0.0008 mg/L. Atrazine showed LC50 at concentrations of 40 mg/L and 7 mg/L for 24 and 48 hours, respectively. We demonstrated that exposure to ecologically relevant concentrations of Roundup or Atrazine decreases lipid peroxidation and protein thiol levels, however caused increase in carbonyl protein and low-molecular-weight thiols content. Moreover, the herbicide treatments caused increase of superoxide dismutase activity. Our data suggest that at very low concentrations Roundup and Atrazine disturb free radical processes in D. magna. [ABSTRACT FROM AUTHOR]

Abstract: Cobalt (Co2+) is present in many nanoscaled materials created for various applications. The key goal of our study was to develop sensitive approaches for assessing the bio-risks associated with using novel Co2+-containing nanoscaled polymeric complex (Co-NC). Freshwater bivalve mollusk Anodonta cygnea (Unionidae) was subjected to 14d action of the developed Co-NC, as well as of Co2+ applied in the corresponding concentration (50μgL−1) or polymeric substance (PS). All experimental groups under study have demonstrated signs of toxic targeting, notably changes in DNA characteristics, oxidative stress (with particularities in each exposed group) and activation of anaerobiosis (Co2+ and Co-NC). However, the group exposed to Co-NC showed some advantages that can be related to the activation of metallothionein (MT) function (increase in the level of MT-related SH-groups (MT-SH)): low level of oxyradical formation, no increase in protein carbonylation and vitellogenin-like proteins concentration unlike in Co2+ and PS exposed groups. On the other hand, Co2+ increased metal (Co, Cu, Zn and Cd) binding to MT (MT-Me) without changes in MT-SH level jointly with activation of oxyradical formation and apoptosis and decreasing of lysosomal membrane stability. PS per se initiated unbalanced changes in activities of the biotransformation enzymes ethoxyresorufin-O-deethylase and glutathione-S-transferase. Thus, Co2+ complexing with the developed PS prevented bio-toxic effects of free Co2+ ions and PS per se, at least in the studied hydrobiont. The MT-SH was the main distinguishing index of Co-NC group selected by classification and regression tree analysis. [Copyright &y& Elsevier]

Hypoxia is a major stressor in estuarine and coastal habitats, leading to adverse effects in aquatic organisms. Estuarine bivalves such as blue mussels ( Mytilus edulis ) and Pacific oysters ( Crassostrea gigas ) can survive periodic oxygen deficiency but the molecular mechanisms that underlie cellular injury during hypoxia-reoxygenation are not well understood. We examined the molecular markers of autophagy, apoptosis and inflammation during short-term (1 day) and long-term (6 days) hypoxia and post-hypoxic recovery (1 h) in mussels and oysters by measuring the lysosomal membrane stability, activity of a key autophagic enzyme (cathepsin D) and mRNA expression of the genes involved in the cellular survival and inflammation, including caspase 2, 3 and 8, Bcl-2, BAX, TGF-β-activated kinase 1 (TAK1), nuclear factor kappa B1 (NF-κB) and NF-κB activating kinases IKKα and TBK1. Crassostrea gigas exhibited higher hypoxia tolerance, as well as blunted or delayed inflammatory and apoptotic response to hypoxia and reoxygenation as shown by the later onset and/or the lack of transcriptional activation of caspases, BAX and the inflammatory effector NF-κB, compared with M. edulis Long-term hypoxia resulted in upregulation of Bcl-2 in the oysters and mussels, implying activation of anti-apoptotic mechanisms. Our findings indicate the potential importance of the cell survival pathways in hypoxia tolerance of marine bivalves, and demonstrate the utility of the molecular markers of apoptosis and autophagy for the assessment of sublethal hypoxic stress in bivalve populations., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2020. Published by The Company of Biologists Ltd.)