# Bulletin de veille du réseau d'écotoxicologie terrestre et aquatique N°44

Colette Bertrand, Christian Mougin, Annette Bérard, Céline Pelosi, Soizic Morin, Olivier Crouzet, Pascale Karmasyn-Veyrines

## ► To cite this version:

Colette Bertrand, Christian Mougin, Annette Bérard, Céline Pelosi, Soizic Morin, et al., Bulletin de veille du réseau d'écotoxicologie terrestre et aquatique N°44. 2020, 10.15454/CMHM-JQ56 hal-02865248v2

HAL Id: hal-02865248

https://hal.inrae.fr/hal-02865248v2

Submitted on 13 Jul 2021

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# Bulletin de veille du réseau d'écotoxicologie terrestre et aquatique

<figure><img src="image_2.png" /></figure>

N°44, Avril 2020

Réalisé par l'équipe de veille sur la période du 1er mars au 30 avril 2020.

Colette Bertrand, Christian Mougin (UMR 1402 EcoSys), Annette Berard, Céline Pélosi (UMR 1114 EMMAH), Soizic Morin (UR 1454 EABX), Olivier Crouzet (UPFS - OFB) et Pascale Karmasyn-Veyrines (DipSO)

Destinataires : les membres de la liste : [ecotox@inrae.fr](mailto:ecotox@inrae.fr)

## Edito

Voici notre 44ème bulletin de veille, très dense ! Faut-il y voir un effet du confinement, et/ou un renforcement de l'équipe de veilleurs ??? Vous y trouverez de très nombreuses informations en lien avec l'écotoxicologie et la toxicologie. Nous vous proposons en pages 102-106 une présentation épurée des articles cités. Merci de nous faire un retour sur votre perception de ce format ! Pas de rubrique « colloques », ceux-dont nous avions connaissance ont été annulés. Il en est ainsi du colloque de la SEFA reporté à 2021.

Nous vous proposons dans ce bulletin une tribune présentant la règlementation sur les ressources génétiques et ses conséquences pour les recherches en écotoxicologie. Le texte est également disponible sous forme de fiche thématique en téléchargement sur notre site ECOTOX :
[https://www6.inrae.fr/ecotox/Productions/Fiches-thematiques/Fiche-thematique-N-26-avril-2020](https://www6.inrae.fr/ecotox/Productions/Fiches-thematiques/Fiche-thematique-N-26-avril-2020)

N'oubliez pas de nous transmettre les informations que vous souhaitez diffuser, notamment vos publications que nous pourrions avoir oubliées.

L'équipe vous souhaite une bonne santé, un déconfinement sécurisé... et une bonne lecture de ce bulletin !

Contact : [veille-ecotox@inrae.fr](mailto:veille-ecotox@inrae.fr)
<table><tr><td>Characterization of indigenous bacteria from radon-rich groundwater and their tolerance to physicochemical stress</td><td>34</td></tr><tr><td>Highlighting of the antialgal activity of organic extracts of Moroccan macrophytes: potential use in cyanobacteria blooms control</td><td>34</td></tr><tr><td>Toxicity evaluation of iron oxide nanoparticles and accumulation by microalgae <i>Coelastrella terrestris</i></td><td>35</td></tr><tr><td>Pollution shapes the bacterial community of a river: a case study</td><td>35</td></tr><tr><td>pH affects the hormesis profiles of personal care product components on luminescence of the bacteria <i>Vibrio qinghaiensis</i> sp.-Q67</td><td>36</td></tr><tr><td>Multistressor negative effects on an experimental phytoplankton community. The case of glyphosate and one toxigenic cyanobacterium on Chlorophyceon microalgae</td><td>36</td></tr><tr><td>Bacteria-nanoparticle interactions in the context of nanofouling</td><td>37</td></tr><tr><td>Effect of trace metals on growth performance and accumulation of lipids, proteins, and carbohydrates on the green microalga <i>Scenedesmus obliquus</i></td><td>37</td></tr><tr><td>Effects of elutriates from contaminated coastal sediments on different life cycle phases of planktonic diatoms</td><td>38</td></tr><tr><td>Quantitative proteomic analysis provides insights into the algicidal mechanism of Halobacillus sp. P1 against the marine diatom <i>Skeletonema costatum</i></td><td>38</td></tr><tr><td>Influence of multi-walled carbon nanotubes on the microbial biomass, enzyme activity, and bacterial community structure in 2,4-dichlorophenol-contaminated sediment</td><td>39</td></tr><tr><td>Periphytic biofilm: An innovative approach for biodegradation of microplastics</td><td>39</td></tr><tr><td>Ecotoxicity of polyethylene nanoplastics from the North Atlantic oceanic gyre on freshwater and marine organisms (microalgae and filter-feeding bivalves)</td><td>40</td></tr><tr><td>Evolution and distribution of resistance genes and bacterial community in water and biofilm of a simulated fish-duck integrated pond with stress</td><td>40</td></tr><tr><td>A global metabolomic insight into the oxidative stress and membrane damage of copper oxide nanoparticles and microparticles on microalga <i>Chlorella vulgaris</i></td><td>41</td></tr><tr><td>Toxicity, Biodegradation, and Metabolic Fate of Organophosphorus Pesticide Trichlorfon on the Freshwater Algae <i>Chlamydomonas reinhardtii</i></td><td>42</td></tr><tr><td>Differential responses of two cyanobacterial species to R-metalaxyl toxicity: Growth, photosynthesis and antioxidant analyses</td><td>42</td></tr><tr><td>Aluminium triggers oxidative stress and antioxidant response in the microalgae <i>Scenedesmus</i> sp</td><td>42</td></tr><tr><td>Spatial distribution characteristics of bacterial community structure and gene abundance in sediments of the Bohai Sea</td><td>43</td></tr><tr><td>Silver nanoparticle and Ag+-induced shifts of microbial communities in natural brackish waters: Are they more pronounced under oxic conditions than anoxic conditions?</td><td>43</td></tr><tr><td>Enhanced bactericidal effect of ceftriaxone drug encapsulated in nanostructured lipid carrier against gram-negative <i>Escherichia coli</i> bacteria: drug formulation, optimization, and cell culture study</td><td>44</td></tr><tr><td>Combating the prevalence of water-borne bacterial pathogens using anisotropic structures of silver nanoparticles</td><td>44</td></tr><tr><td>Insights into the transcriptional responses of a microbial community to silver nanoparticles in a freshwater microcosm</td><td>45</td></tr><tr><td>Growth inhibition of eutrophication water by white-rot fungus</td><td>45</td></tr><tr><td>Inhibitory efficacy of white-rot fungus against harmful freshwater algal bloom species</td><td>46</td></tr><tr><td>Microbial Colonization in Marine Environments: Overview of Current Knowledge and Emerging Research Topics</td><td>46</td></tr><tr><td>Marine Actinobacteria: Screening for Predation Leads to the Discovery of Potential New Drugs against Multidrug-Resistant Bacteria</td><td>47</td></tr><tr><td>Water environments: metal-tolerant and antibiotic-resistant bacteria</td><td>47</td></tr><tr><td>Simultaneous enhancement of heavy metal removal and electricity generation in soil microbial fuel cell</td><td>47</td></tr><tr><td>Bioremediation of heavy metals using microalgae: Recent advances and mechanisms</td><td>48</td></tr><tr><td>Bacterial Disinfection by CuFe2O4 Nanoparticles Enhanced by NH2OH: A Mechanistic Study</td><td>48</td></tr><tr><td>Hierarchical Cluster Analysis of Medical Chemicals Detected by a Bacteriophage-Based Colorimetric Sensor Array</td><td>48</td></tr><tr><td>Quantifying the Mineralization of C-13-Labeled Cations and Anions Reveals Differences in Microbial Biodegradation of Herbicidal Ionic Liquids between Water and Soil</td><td>49</td></tr><tr><td>Heavy metal resistance and metallothionein induction in bacteria isolated from Seybouse River, Algeria</td><td>49</td></tr><tr><td>A novel Cyphos IL 104-based polymer inclusion membrane (PIM) probe to mimic biofilm zinc accumulation</td><td>50</td></tr><tr><td>Amoxicillin removal by pre-denitrification membrane bioreactor (A/O-MBR): Performance evaluation, degradation</td><td></td></tr></table>
<table><tr><td>by-products, and antibiotic resistant bacteria</td><td>50</td></tr><tr><td>Effects of soil chemical properties and fractions of Pb, Cd, and Zn on bacterial and fungal communities</td><td>51</td></tr><tr><td>Microbial degradation and other environmental aspects of microplastics/plastics</td><td>51</td></tr></table>

ERA / PUBLICATIONS SCIENTIFIQUES / MICROBIOLOGIE ET PESTICIDES 52

<table><tr><td>Long-term application of Swedish sewage sludge on farmland does not cause clear changes in the soil bacterial resistome</td><td>52</td></tr><tr><td>Fifteen-Year Application of Manure and Chemical Fertilizers Differently Impacts Soil ARGs and Microbial Community Structure</td><td>52</td></tr><tr><td>Do combined nanoscale polystyrene and tetracycline impact on the incidence of resistance genes and microbial community disturbance in <i>Enchytraeus crypticus</i>?</td><td>52</td></tr><tr><td>Trophic transfer of pesticides: The fine line between predator-prey regulation and pesticide-pest regulation</td><td>53</td></tr><tr><td>Azoxystrobin dissipation and its effect on soil microbial community structure and function in the presence of chlorothalonil, chlortetracycline and ciprofloxacin</td><td>53</td></tr><tr><td>Short-term application of mulch, roundup and organic herbicides did not affect soil microbial biomass or bacterial and fungal diversity</td><td>54</td></tr><tr><td>A safety type of genetically engineered bacterium that degrades chemical pesticides</td><td>54</td></tr><tr><td>Heavy Metals as a Factor Increasing the Functional Genetic Potential of Bacterial Community for Polycyclic Aromatic Hydrocarbon Biodegradation</td><td>54</td></tr><tr><td>Adsorption performance of <i>Bacillus licheniformis</i> sp. bacteria isolated from the soil of the Tigris River on mercury in aqueous solutions</td><td>55</td></tr><tr><td>Biochar and bacteria inoculated biochar enhanced Cd and Cu immobilization and enzymatic activity in a polluted soil</td><td>55</td></tr><tr><td>Bacterial response to sharp geochemical gradients caused by acid mine drainage intrusion in a terrace: Relevance of C, N, and S cycling and metal resistance</td><td>56</td></tr><tr><td>Comparative assessment of polymeric and other nanoparticles impacts on soil microbial and biochemical properties</td><td>56</td></tr><tr><td>Potency of Phlebia species of white rot fungi for the aerobic degradation, transformation and mineralization of lindane</td><td>57</td></tr><tr><td>Integration of earthworms and arbuscular mycorrhizal fungi into phytoremediation of cadmium-contaminated soil by <i>Solanum nigrum</i> L.</td><td>57</td></tr><tr><td>Evaluation of seven chemical pesticides by mixed microbial culture (PCS-1): Degradation ability, microbial community, and <i>Medicago sativa</i> phytotoxicity</td><td>58</td></tr><tr><td>Design of Bacterial Strain-Specific qPCR Assays Using NGS Data and Publicly Available Resources and Its Application to Track Biocontrol Strains</td><td>58</td></tr><tr><td>Long-term application of Swedish sewage sludge on farmland does not cause clear changes in the soil bacterial resistome</td><td>59</td></tr><tr><td>Microbial Degradation of Plastic in Aqueous Solutions Demonstrated by CO2 Evolution and Quantification</td><td>59</td></tr><tr><td>Effect of cadmium contamination on the rhizosphere bacterial diversity of <i>Echinocactus platyacanthus</i>.</td><td>60</td></tr><tr><td>A new assay of bacterial selection with Pb reveals an unexpected effect of Pb on bacterial behavior: implications for remediation</td><td>60</td></tr><tr><td>Cadmium Pollution Impact on the Bacterial Community of Haplic Cambisols in Northeast China and Inference of Resistant Genera</td><td>60</td></tr><tr><td>Bacteria affect Sb(III, V) adsorption and oxidation on birnessite</td><td>61</td></tr><tr><td>Physiological responses of <i>Morus alba</i> L. in heavy metal(loid)-contaminated soil and its associated improvement of the microbial diversity</td><td>62</td></tr><tr><td>Impacts of antimony and arsenic co-contamination on the river sedimentary microbial community in an antimony-contaminated river</td><td>62</td></tr><tr><td>Sub-Arctic Field Degradation of Metsulfuron-Methyl in Two Alaskan Soils and Microbial Community Composition Effects</td><td>63</td></tr><tr><td>Influence of multi-walled carbon nanotubes on the microbial biomass, enzyme activity, and bacterial community structure in 2,4-dichlorophenol-contaminated sediment</td><td>63</td></tr><tr><td>Effects of electron donors on the degradation of hexachlorocyclohexane and microbial community in submerged soils</td><td>64</td></tr></table>
<table><tr><td>Pesticide application inhibit the microbial carbonic anhydrase-mediated carbon sequestration in a soil microcosm</td><td>64</td></tr><tr><td>Challenges with Verifying Microbial Degradation of Polyethylene</td><td>65</td></tr><tr><td>Phytostabilization of Polluted Military Soil Supported by Bioaugmentation with PGP-Trace Element Tolerant Bacteria Isolated from Helianthus petiolaris</td><td>65</td></tr><tr><td>Sulfate-reducing bacteria (SRB) can enhance the uptake of silver-containing nanoparticles by a wetland plant</td><td>66</td></tr><tr><td>Comparative Genomics of a Paddy Field Bacterial Isolate Ochrobactrum sp. CPD-03: Analysis of Chlorpyrifos Degradation Potential</td><td>66</td></tr><tr><td>Influence of the herbicide haloxyfop-R-methyl on bacterial diversity in rhizosphere soil of <i>Spartina alterniflora</i></td><td>66</td></tr><tr><td>Optimized bioleaching of copper by indigenous cyanogenic bacteria isolated from the landfill of e-waste</td><td>67</td></tr><tr><td>Construction of a Tetracycline Degrading Bacterial Consortium and Its Application Evaluation in Laboratory-Scale Soil Remediation</td><td>67</td></tr><tr><td>Effects of soil heavy metal pollution on microbial activities and community diversity in different land use types in mining areas</td><td>68</td></tr><tr><td>Tetracyclines Mode of Action and their Bacterial Mechanisms of Resistance</td><td>68</td></tr><tr><td>Urban and agricultural soils in Southern California are a reservoir of carbapenem-resistant bacteria</td><td>69</td></tr><tr><td>On the contribution of reclaimed wastewater irrigation to the potential exposure of humans to antibiotics, antibiotic resistant bacteria and antibiotic resistance genes - NEREUS COST Action ES1403 position paper</td><td>69</td></tr><tr><td>Co-effect of minerals and Cd(II) promoted the formation of bacterial biofilm and consequently enhanced the sorption of Cd(II)</td><td>69</td></tr><tr><td>Removal of Heavy Metals Zinc, Lead, and Cadmium by Biomineralization of Urease-Producing Bacteria Isolated from Iranian Mine Calcareous Soils</td><td>70</td></tr><tr><td>Isotope Fractionation (delta C-13, delta N-15) in the Microbial Degradation of Bromoxynil by Aerobic and Anaerobic Soil Enrichment Cultures</td><td>70</td></tr><tr><td>Effects of modified nanoscale carbon black on plant growth, root cellular morphogenesis, and microbial community in cadmium-contaminated soil</td><td>71</td></tr><tr><td>Significance of soil microbe in microbial-assisted phytoremediation: an effective way to enhance phytoremediation of contaminated soil</td><td>71</td></tr><tr><td>Long-term effects of chlorothalonil on microbial denitrification and N2O emission in a tea field soil</td><td>72</td></tr><tr><td>Soil exposed to silver nanoparticles reveals significant changes in community structure and altered microbial transcriptional profiles</td><td>72</td></tr><tr><td>Arbuscular Mycorrhizal Fungi (AMF) from Heavy Metal-Contaminated Soils: Molecular Approach and Application in Phytoremediation</td><td>73</td></tr><tr><td>Tolerance of dark septate endophytic fungi (DSE) to agrochemicals in vitro</td><td>73</td></tr><tr><td>Temporal effects of repeated application of biogas slurry on soil antibiotic resistance genes and their potential bacterial hosts</td><td>73</td></tr><tr><td>Evaluation of degradation of a novel sulfone bactericide in soils: identification of degradation product and kinetics study</td><td>74</td></tr><tr><td>Inoculation with abscisic acid (ABA)-catabolizing bacteria can improve phytoextraction of heavy metal in contaminated soil</td><td>74</td></tr><tr><td>Bioremediation of Oxamyl Compounds by Algae: Description and Traits of Root-Knot Nematode Control</td><td>75</td></tr><tr><td>The toxic factor of copper should be adjusted during the ecological risk assessment for soil bacterial community</td><td>75</td></tr><tr><td>Amelioration of chromium and heat stresses in <i>Sorghum bicolor</i> by Cr6+ reducing-thermotolerant plant growth promoting bacteria</td><td>76</td></tr><tr><td>Microbial diversity in soils from antimony mining sites: geochemical control promotes species enrichment</td><td>76</td></tr><tr><td>Effective bioremediation of heavy metal-contaminated landfill soil through bioaugmentation using consortia of fungi</td><td>77</td></tr><tr><td>Azoxystrobin dissipation and its effect on soil microbial community structure and function in the presence of chlorothalonil, chlortetracycline and ciprofloxacin</td><td>77</td></tr><tr><td>Metal-Tolerant Fungal Communities Are Delineated by High Zinc, Lead, and Copper Concentrations in Metalliferous Gobi Desert Soils</td><td>78</td></tr><tr><td>Short-term application of mulch, roundup and organic herbicides did not affect soil microbial biomass or bacterial and fungal diversity</td><td>78</td></tr><tr><td>Design of a degenerate primer pair to target a bacterial functional community: The hppd bacterial gene coding for the enzyme targeted by herbicides, a study case</td><td>79</td></tr></table>
<table><tr><td>Study on degradation of chlorpyrifos-methyl and utilization of chlorpyrifos-methyl drading vacterium, <i>Bacillus vallismortis</i> CM-11</td><td>79</td></tr><tr><td>Temporal dynamics of earthworm (<i>Eisenia fetida</i>) microbial communities after cadmium stress based on a compound mathematical model</td><td>79</td></tr><tr><td>Mercury alters the rhizobacterial community in Brazilian wetlands and it can be bioremediated by the plant-bacteria association</td><td>80</td></tr><tr><td>Heavy metals, antibiotics and nutrients affect the bacterial community and resistance genes in chicken manure composting and fertilized soil</td><td>80</td></tr><tr><td>The combined effects of treated wastewater irrigation and plastic mulch cover on soil and crop microbial communities</td><td>81</td></tr><tr><td>Do combined nanoscale polystyrene and tetracycline impact on the incidence of resistance genes and microbial community disturbance in <i>Enchytraeus crypticus</i>?</td><td>81</td></tr><tr><td>Microbial and Viral Communities and Their Antibiotic Resistance Genes Throughout a Hospital Wastewater Treatment System</td><td>82</td></tr><tr><td>Rhizoremediation of Cu(II) ions from contaminated soil using plant growth promoting bacteria: an outlook on pyrolysis conditions on plant residues for methylene orange dye biosorption</td><td>82</td></tr><tr><td>Isolation of urease-producing bacteria and their effects on reducing Cd and Pb accumulation in lettuce (<i>Lactuca sativa</i> L.)</td><td>83</td></tr><tr><td>Uranium tolerant phosphate solubilizing bacteria isolated from Gogi, a proposed uranium mining site in South India</td><td>83</td></tr><tr><td>Characteristics and in situ remediation effects of heavy metal immobilizing bacteria on cadmium and nickel co-contaminated soil</td><td>84</td></tr><tr><td>Quantifying the Mineralization of C-13-Labeled Cations and Anions Reveals Differences in Microbial Biodegradation of Herbicidal Ionic Liquids between Water and Soil</td><td>84</td></tr><tr><td>Microbial inoculant and garbage enzyme reduced cadmium (Cd) uptake in <i>Salvia miltiorrhiza</i> (Bge.) under Cd stress</td><td>85</td></tr><tr><td>Impact of pesticide monocrotophos on microbial populations and histology of intestine in the Indian earthworm Lampito mauritii (Kinberg)</td><td>85</td></tr><tr><td>Soil Microbial Communities in Diverse Agroecosystems Exposed to the Herbicide Glyphosate</td><td>86</td></tr><tr><td>Zinc resistance of six dark septate endophytic fungi and the growth response of tomato</td><td>86</td></tr><tr><td>Effects of soil chemical properties and fractions of Pb, Cd, and Zn on bacterial and fungal communities</td><td>87</td></tr><tr><td>Optimization of Paraquat degradation with microbial consortium from contaminated soil using statistic method</td><td>87</td></tr><tr><td>A slurry microcosm study on the interaction between antibiotics and soil bacterial community</td><td>88</td></tr><tr><td>Role of extracellular polymeric substance (EPS) in toxicity response of soil bacteria <i>Bacillus</i> sp. S3 to multiple heavy metals</td><td>88</td></tr><tr><td>Microsegmented flow-assisted miniaturized culturing for isolation and characterization of heavy metal-tolerant bacteria</td><td>89</td></tr><tr><td>Incorporation of cyclodiene pesticides and their polar metabolites to model membranes of soil bacteria</td><td>89</td></tr><tr><td>Fire Phoenix facilitates phytoremediation of PAH-Cd co-contaminated soil through promotion of beneficial rhizosphere bacterial communities</td><td>90</td></tr><tr><td>Effects of pesticide residues on bacterial community diversity and structure in typical greenhouse soils with increasing cultivation years in Northern China</td><td>90</td></tr><tr><td>Exploring bacterial community composition in Mediterranean deep-sea sediments and their role in heavy metal accumulation</td><td>91</td></tr><tr><td>Responses of bacterial communities in wheat rhizospheres in different soils to di-n-butyl and di(2-ethylhexyl)phthalate contamination</td><td>91</td></tr><tr><td>The utilization of biomineralization technique based on microbial induced phosphate precipitation in remediation of potentially toxic ions contaminated soil: A mini review</td><td>92</td></tr><tr><td>Effect of the veterinary ionophore monensin on the structure and activity of a tropical soil bacterial community</td><td>92</td></tr><tr><td>Associative effects of lignin-derived biochar and arbuscular mycorrhizal fungi applied to soil polluted from Pb-acid batteries effluents on barley grain safety</td><td>92</td></tr><tr><td>Effects of Soil Amendments on Microbial Activities in a Typical Cd-Contaminated Purple Field Soil, Southwestern China</td><td>93</td></tr><tr><td>Biodegradation of Organophosphorus Compounds Predicted by Enzymatic Process Using Molecular Modelling and</td><td></td></tr></table>
<table><tr><td>Observed in Soil Samples Through Analytical Techniques and Microbiological Analysis: A Comparison</td><td>93</td></tr><tr><td>Enhanced bioremediation of lindane-contaminated soils through microbial bioaugmentation assisted by biostimulation with sugarcane filter cake</td><td>94</td></tr><tr><td>Variation in soil microbial population and enzyme activities under faba bean as affected by pentachlorophenol</td><td>95</td></tr><tr><td>Development of microbial communities in organochlorine pesticide contaminated soil: A post-reclamation perspective</td><td>95</td></tr><tr><td>Biodegradation and biotransformation of pentachlorophenol by wood-decaying white rot fungus Phlebia acanthocystis TMIC34875</td><td>96</td></tr><tr><td>Impacts of Cu and sulfadiazine on soil potential nitrification and diversity of ammonia-oxidizing archaea and bacteria</td><td>96</td></tr><tr><td>Hydrogeochemical and microbiological effects of simulated recharge and drying within a 2D meso-scale aquifer</td><td>97</td></tr><tr><td>Association between antibiotic residues, antibiotic resistant bacteria and antibiotic resistance genes in anthropogenic wastewater - An evaluation of clinical influences</td><td>97</td></tr><tr><td>Antibiotic Residues and Antibiotic-Resistant Bacteria in Pig Slurry Used to Fertilize Agricultural Fields</td><td>98</td></tr><tr><td>Characterization of tetracycline effects on microbial community, antibiotic resistance genes and antibiotic resistance of Aeromonas spp. in gut of goldfish Carassius auratus Linnaeus</td><td>98</td></tr><tr><td>Rapid elimination of foodborne and environmental fungal contaminants by benzo analogs</td><td>99</td></tr></table>

<table><tr><td>ERA / PUBLICATIONS SCIENTIFIQUES / PESTICIDES ET FAUNE SAUVAGE</td><td>99</td></tr><tr><td>Oxidative stress risk assessment through heavy metal and arsenic exposure in terrestrial and aquatic bird species of Pakistan</td><td>99</td></tr><tr><td>Content of essential and non-essential elements in wild animals from western Ukraine and the health risks associated with meat and liver consumption</td><td>99</td></tr><tr><td>Ingestion of unusual items by wetland birds in urban landscapes Microsoft Word</td><td>100</td></tr><tr><td>Organic farming benefits birds most in regions with more intensive agriculture</td><td>100</td></tr><tr><td>Juvenile Toxicity Rodent Model to Study Toxicological Effects of Bisphenol A (BPA) at Dose Levels Derived from Italian Children</td><td>100</td></tr><tr><td>Uptake, Metabolism, and Elimination of Fungicides from Coated Wheat Seeds in Japanese Quail (Coturnix japonica)</td><td>101</td></tr></table>

<table><tr><td>ERA / PUBLICATIONS SCIENTIFIQUES / PESTICIDES/CLIMAT ET VDT/ENCHYTREIDES</td><td>101</td></tr><tr><td>Enchytraeus crypticus Avoid Soil Spiked with Microplastic</td><td>101</td></tr><tr><td>Opening a can of worms: Can the availability of soil invertebrates be indicated by birds?</td><td>101</td></tr><tr><td>Effects of elevated temperatures and cadmium exposure on stress biomarkers at different biological complexity levels in Eisenia fetida earthworms</td><td>102</td></tr><tr><td>Evaluating the effects of the tebuconazole on the earthworm, Eisenia fetida by H-1 NMR-Based untargeted metabolomics and mRNA assay</td><td>102</td></tr><tr><td>Impact of temperature on the toxicity of Kraft 36 EC (R) (a.s. abamectin) and Score 250 EC (R) (a.s. difenoconazole) to soil organisms under realistic environmental exposure scenarios</td><td>102</td></tr><tr><td>Combined effects of goethite nanoparticles with metallic contaminants and an organophosphorus pesticide on Eisenia andrei</td><td>102</td></tr><tr><td>Effect of phenanthrene on the biological characteristics of earthworm casts and their relationships with digestive and anti-oxidative systems</td><td>102</td></tr><tr><td>Exposure of earthworm (Eisenia fetida) to bauxite residue: Implications for future rehabilitation programmes</td><td>103</td></tr><tr><td>Toxicity of imidacloprid to the earthworm Eisenia andrei and collembolan Folsomia candida in three contrasting tropical soils</td><td>103</td></tr><tr><td>Applying fungicide on earthworms: Biochemical effects of Eisenia fetida exposed to fluoxastrobin in three natural soils</td><td>103</td></tr><tr><td>A reconsideration of the safety of fenoxycarb (IGR) in soil environment: The toxicity of fenoxycarb to Yuukianura szeptyckii (Collembola)</td><td>103</td></tr><tr><td>Impact of pesticide monocrotophos on microbial populations and histology of intestine in the Indian earthworm Lampito mauritii (Kinberg)</td><td>103</td></tr><tr><td>A sensitive optical-based test method for the locomotor activity of earthworms</td><td>103</td></tr><tr><td>Toxicity in Neonicotinoids to Folsomia candida and Eisenia andrei</td><td>104</td></tr></table>
<table><tr><td>Biochemical responses and DNA damage induced by herbicide QYR301 in earthworm (Eisenia fetida)</td><td>104</td></tr><tr><td>An energy-based model to analyze growth data of earthworms exposed to two fungicides</td><td>104</td></tr><tr><td>First report on a classification-based QSAR model for chemical toxicity to earthworm</td><td>104</td></tr><tr><td>The sublethal lead (Pb) toxicity to the earthworm Eisenia fetida (Annelida, Oligochaeta) as affected by NaCl salinity and manure addition in a calcareous clay loam soil during an indoor mesocosm experiment</td><td>104</td></tr><tr><td>Glyphosate spraying and earthworm Lumbricus terrestris L. activity: Evaluating short-term impact in a glasshouse experiment simulating cereal post-harvest</td><td>105</td></tr><tr><td>Glyphosate but not Roundup harms earthworms (Eisenia fetida)</td><td>105</td></tr><tr><td>Individual and cellular responses of earthworms (Eisenia fetida) to endosulfan at environmentally related concentrations</td><td>105</td></tr><tr><td>Leaching of insecticides used in blueberry production and their toxicity to red worm</td><td>105</td></tr><tr><td>Exploring QSAR modeling of toxicity of chemicals on earthworm</td><td>105</td></tr></table>

<table><tr><td>DROIT ET POLITIQUE DE L'ENVIRONNEMENT</td><td>105</td></tr><tr><td>Le réseau d'épidémiosurveillance financé par le plan Ecophyto - Réorientations à opérer</td><td>105</td></tr></table>

<table><tr><td>DROIT ET REGLEMENTATION</td><td>106</td></tr><tr><td>Produits biocides «HYPRED's octanoic acid based products» : règlement d'autorisation de l'Union</td><td>106</td></tr><tr><td>Famille de produits biocides «SOPURCLEAN» : règlement d'autorisation de l'Union</td><td>106</td></tr><tr><td>Suspension d'introduction, d'importation et de mise sur le marché en France de cerises fraîches destinées à l'alimentation produites dans un pays autorisant le traitement des cerisiers avec des produits phytopharmaceutiques contenant la substance active diméthoate</td><td>106</td></tr><tr><td>Prolongation de la période d'approbation des substances actives «abamectine»</td><td>106</td></tr><tr><td>Produits phytopharmaceutiques : autorisations de mise sur le marché d'une durée maximale de 120 jours délivrées par le ministère dans des situations d'urgence phytosanitaire</td><td>107</td></tr><tr><td>Liste des produits de biocontrôle</td><td>107</td></tr></table>

<table><tr><td>REGLEMENTATION / DEBAT</td><td>107</td></tr><tr><td>Parliament objects to lead in PVC to protect public health and the environment</td><td>107</td></tr></table>

<table><tr><td>AVIS / EXPERTISES / NORMES</td><td>108</td></tr><tr><td>Outcome of the consultation with Member States, the applicant and EFSA on the pesticide risk assessment for isopyrazam in light of confirmatory data</td><td>108</td></tr></table>

<table><tr><td>PUBLICATIONS DU RESEAU ECOTOX</td><td>108</td></tr><tr><td>Potential Use of Earthworms to Enhance Decaying of Biodegradable Plastics</td><td>108</td></tr><tr><td>Genotoxicity in the rivers from the Brantas catchment (East Java, Indonesia): occurrence in sediments and effects in Oreochromis niloticus (Linn AE us 1758)</td><td>109</td></tr><tr><td>Determination of polycyclic aromatic hydrocarbon (PAH) contents in micro-volumes of the whole blood and liver of Red Kite by a simplified GC-MS/MS method</td><td>109</td></tr><tr><td>Health risk assessment to dioxins, furans and PCBs in young children: The first French evaluation</td><td>109</td></tr><tr><td>Improving Silver Birch (Betula pendula) Growth and Mn Accumulation in Residual Red Gypsum Using Organic Amendments</td><td>110</td></tr><tr><td>Inorganic Mercury and Methyl-Mercury Uptake and Effects in the Aquatic Plant Elodea nuttallii: A Review of Multi-Omic Data in the Field and in Controlled Conditions</td><td>110</td></tr><tr><td>Accumulation, speciation and localization of silver nanoparticles in the earthworm Eisenia fetida</td><td>111</td></tr><tr><td>Is metallothionein in Mimachlamys varia a suitable biomarker of trace elements in the waters of the French Atlantic coast?</td><td>111</td></tr><tr><td>Changes in sediment microbial diversity following chronic copper-exposure induce community copper-tolerance without increasing sensitivity to arsenic</td><td>112</td></tr><tr><td>Control of poultry contamination in chlordecone-contaminated areas of the French West Indies</td><td>112</td></tr><tr><td>A new protocol for the simultaneous flow cytometric analysis of cytotoxicity and immunotoxicity on zebra mussel (Dreissena polymorpha) hemocytes</td><td>112</td></tr></table>
<table>
  <tr>
    <td>How can interspecific interactions in freshwater benthic macroinvertebrates modify trace element availability from sediment?</td>
    <td>113</td>
  </tr>
  <tr>
    <td>Modelling herbicides mobility in amended soils: Calibration and test of PRZM and MACRO</td>
    <td>114</td>
  </tr>
  <tr>
    <td>Accumulation and immunotoxicity of microplastics in the estuarine worm Hediste diversicolor in environmentally relevant conditions of exposure</td>
    <td>114</td>
  </tr>
  <tr>
    <td>A new assay of bacterial selection with Pb reveals an unexpected effect of Pb on bacterial behavior: implications for remediation</td>
    <td>115</td>
  </tr>
  <tr>
    <td>Effects of in vivo exposure to tritium: a multi-biomarker approach using the fathead minnow, Pimephales promelas</td>
    <td>115</td>
  </tr>
  <tr>
    <td>Assessment of swimming behavior of the Pacific oyster D-larvae (Crassostrea gigas) following exposure to model pollutants</td>
    <td>116</td>
  </tr>
  <tr>
    <td>Sensitivity to cadmium of the endangered freshwater pearl mussel Margaritifera margaritifera from the Dronne River (France): experimental exposure</td>
    <td>116</td>
  </tr>
  <tr>
    <td>Bioaccumulation dynamics and gene regulation in a freshwater bivalve after aqueous and dietary exposures to gold nanoparticles and ionic gold</td>
    <td>117</td>
  </tr>
  <tr>
    <td>Benefits of ozonation before activated carbon adsorption for the removal of organic micropollutants from wastewater effluents</td>
    <td>117</td>
  </tr>
  <tr>
    <td>Health indicators and contaminant levels of a critically endangered species in the Gironde estuary, the European sturgeon</td>
    <td>118</td>
  </tr>
  <tr>
    <td>Towards simple tools to assess functional effects of contaminants on natural microbial and invertebrate sediment communities</td>
    <td>118</td>
  </tr>
  <tr>
    <td>Evaluation of the environmental and human health risk related to metallic contamination in agricultural soils in the Mediterranean semi-arid area (Saiss plain, Morocco)</td>
    <td>119</td>
  </tr>
  <tr>
    <td>Barrage fishponds, a funnel effect for metal contaminants on headwater streams</td>
    <td>119</td>
  </tr>
  <tr>
    <td>Biomarker responses and accumulation of polycyclic aromatic hydrocarbons in Mytilus trossulus and Gammarus oceanicus during exposure to crude oil</td>
    <td>120</td>
  </tr>
  <tr>
    <td>Design of a degenerate primer pair to target a bacterial functional community: The hppd bacterial gene coding for the enzyme targeted by herbicides, a study case</td>
    <td>120</td>
  </tr>
  <tr>
    <td>Wastewater-based epidemiology approach to assess population exposure to pesticides: a review of a pesticide pharmacokinetic dataset</td>
    <td>120</td>
  </tr>
  <tr>
    <td>Trophic transfer of pesticides: The fine line between predator-prey regulation and pesticide-pest regulation</td>
    <td>121</td>
  </tr>
  <tr>
    <td>How effective are strategies to control the dissemination of antibiotic resistance in the environment? A systematic review</td>
    <td>122</td>
  </tr>
  <tr>
    <td>Refinement of an OECD test guideline for evaluating the effects of endocrine disrupting chemicals on aromatase gene expression and reproduction using novel transgenic cyp19a1a-eGFP zebrafish</td>
    <td>122</td>
  </tr>
  <tr>
    <td>Influence of dissolved organic matter on the removal of 12 organic micropollutants from wastewater effluent by powdered activated carbon adsorption</td>
    <td>123</td>
  </tr>
  <tr>
    <td>Development and environmental implication of pedotransfer functions of Cd desorption rate coefficients in historically polluted soils</td>
    <td>123</td>
  </tr>
  <tr>
    <td>Exposure to environmental radionuclides alters mitochondrial DNA maintenance in a wild rodent</td>
    <td>124</td>
  </tr>
  <tr>
    <td>An energy-based model to analyze growth data of earthworms exposed to two fungicides</td>
    <td>124</td>
  </tr>
  <tr>
    <td>Effects of cadmium, inorganic mercury and methyl-mercury on the physiology and metabolomic profiles of shoots of the macrophyte Elodea nuttallii</td>
    <td>125</td>
  </tr>
  <tr>
    <td>Increased soil pH and dissolved organic matter after a decade of organic fertilizer application mitigates copper and zinc availability despite contamination</td>
    <td>125</td>
  </tr>
  <tr>
    <td>Realistic environmental exposure to microplastics does not induce biological effects in the Pacific oyster Crassostrea gigas</td>
    <td>126</td>
  </tr>
  <tr>
    <td>Identification of new microbial functional standards for soil quality assessment</td>
    <td>126</td>
  </tr>
  <tr>
    <td>Azadirachtin, a natural pesticide with multiple effects</td>
    <td>127</td>
  </tr>
  <tr>
    <td>Tritiated Water Exposure in Zebrafish (Danio rerio): Effects on the Early-Life Stages</td>
    <td>127</td>
  </tr>
  <tr>
    <td>In Situ Reproductive Bioassay with Caged Gammarus fossarum (Crustacea): Part 2-Evaluating the Relevance of Using a Molt Cycle Temperature-Dependent Model as a Reference to Assess Toxicity in Freshwater Monitoring</td>
    <td>128</td>
  </tr>
  <tr>
    <td>Metabolome response to anthropogenic contamination on microalgae: a review</td>
    <td>128</td>
  </tr>
  <tr>
    <td>Bioaccessibility of metal(loid)s in soils to humans and their bioavailability to snails: A way to associate human</td>
    <td></td>
  </tr>
</table>
<table><tr><td>health and ecotoxicological risk assessment?</td><td>128</td></tr><tr><td>Influence of the properties of 7 micro-grain activated carbons on organic micropollutants removal from wastewater effluent</td><td>129</td></tr></table>

<table><tr><td>REVUE DE PRESSE / ALTERNATIVES / BIOPESTICIDES</td><td>129</td></tr><tr><td>Une alternative aux produits phytos ? BASF et De Sangosse vont tester les produits d'Amoeba</td><td>129</td></tr><tr><td>Corteva lance Inatreq contre la septoriose</td><td>130</td></tr><tr><td>Biocontrôle : Céline Barthet, élue présidente d'IBMA France</td><td>130</td></tr></table>

<table><tr><td>REVUE DE PRESSE / ASSOCIATIONS</td><td>130</td></tr><tr><td>Alerte aux pucerons : les betteraviers démunis à cause des mesures dites « environnementales »</td><td>130</td></tr><tr><td>Pourquoi il est urgent de soutenir l'Initiative Citoyenne Européenne pour une sortie des pesticides « Sauvez les abeilles et les agriculteurs »?</td><td>130</td></tr><tr><td>Retour sur l'affaire glyphosate : affaire de gros sous aux USA, combat idéologique en Europe</td><td>130</td></tr><tr><td>Recours juridiques : Le COVID ne justifie pas d'épandre des pesticides au ras des habitations</td><td>131</td></tr><tr><td>Billet du président -Pesticides - L'inadmissible décision gouvernementale !</td><td>131</td></tr><tr><td>Glyphosate : toujours pas de solution pour le remplacer et une échéance qui approche en plein chaos économique</td><td>131</td></tr><tr><td>Animal Fodder - A Driver of the Global Highly Hazardous Pesticides (HHPs) Industry</td><td>132</td></tr><tr><td>One Quarter of Global Insect Population Lost Since 1990</td><td>132</td></tr><tr><td>Monarch Butterfly Larvae Adversely Affected by Pesticide Drift from Contiguous Soybean and Maize Crop Fields</td><td>132</td></tr><tr><td>Gironde : « on va droit dans le mur, tu viens avec nous ? » dit la filière agricole aux ONG</td><td>132</td></tr><tr><td>Les étranges considérations du Sénateur Corbisez sur les pesticides</td><td>133</td></tr><tr><td>Épandage des pesticides : Les préfets doivent protéger les riverains, pas aggraver la situation !</td><td>133</td></tr><tr><td>Pollinis et Générations Futures déposent un recours contre la cellule Déméter</td><td>133</td></tr><tr><td>Farmed Salmon during Covid-19 Pandemic Subject to Increased Pesticide Use in Scotland</td><td>134</td></tr><tr><td>Farmland Birds' Exposure to Neonicotinoid-Treated Seeds (during Winter Seeding) Confirmed by Blood Plasma Tests</td><td>134</td></tr><tr><td>Household Pesticide Use During Pregnancy Linked to Nephroblastoma Kidney Cancer</td><td>134</td></tr><tr><td>Federal Dietary Guidelines Needed to Promote Sustainably Grown Food for a Healthy Public and Environment, According to Report</td><td>134</td></tr><tr><td>Replay: Les agriculteurs vont-ils sauver la planète?</td><td>135</td></tr><tr><td>Lawsuit Challenges TruGreen Chemical Lawn Care Company for Deceptive Safety Claims; Pesticide Applications Stopped by Some States During COVID-19 Crisis as Nonessential</td><td>135</td></tr><tr><td>Les priorités hallucinantes de Générations Futures</td><td>136</td></tr><tr><td>Agriculture conventionnelle et agriculture biologique : trop de biais dans les comparaisons - Agriculture conventionnelle et agriculture biologique -Trop de biais dans les comparaisons</td><td>136</td></tr><tr><td>Maryland Legislature Passes Limited Ban on Chlorpyrifos Insecticide</td><td>136</td></tr><tr><td>Farmworkers and Conservationists Sue EPA for Re-Approving Monsanto/Bayer's Cancer-Causing Pesticide, Glyphosate/Roundup</td><td>136</td></tr><tr><td>Infectious Human Disease, Snail Fever, Worsened by Pesticide Run-Off into Fresh Waterways</td><td>137</td></tr><tr><td>Monarch Population, Under Threat from Pesticide Use and Habitat Loss, Decline by Half in One Year</td><td>137</td></tr><tr><td>Global Growth of Organic Farmland Further Advances UN Sustainable Development Goals</td><td>137</td></tr><tr><td>L'Union européenne porte un nouveau coup dur au secteur agricole marocain</td><td>137</td></tr><tr><td>Maryland Senate votes to ban pesticide chlorpyrifos</td><td>138</td></tr><tr><td>Future Policy Award for the Protection from Hazardous Chemicals</td><td>138</td></tr><tr><td>As the World Bans Highly Toxic Wood Preservative, Pentachlorophenol, a Low-Income U.S. Community May Be Home to the Last Production Plant</td><td>138</td></tr><tr><td>Ce que coûterait le retrait du glyphosate en arboriculture : entre 120 et 432 euros par hectare</td><td>139</td></tr><tr><td>Tests urinaires à la recherche de glyphosate : les agris donnent de leur personne pour rassurer</td><td>139</td></tr><tr><td>Vidéo virale sur les pesticides dans l'eau : pourquoi l'électrolyse ne prouve rien</td><td>139</td></tr><tr><td>Pesticides interdits en Europe, mais vendus dans les pays du sud</td><td>140</td></tr><tr><td>Baby Bees' Brain Growth Adversely Affected by Neonicotinoid Insecticides</td><td>140</td></tr><tr><td>Locust control campaigns spark health concerns</td><td>140</td></tr></table>
<table><tr><td>Glyphosate Causes Biodiversity Loss in Freshwater Ecosystems</td><td>140</td></tr><tr><td>HEAL response to the Beating Cancer Plan roadmap</td><td>141</td></tr><tr><td>Chemical-Intensive Agriculture Increases Pregnant Mother's Risk of Her Child Developing Leukemia</td><td>141</td></tr></table>

<table><tr><td>REVUE DE PRESSE / RECHERCHE ET MEDIAS</td><td>141</td></tr><tr><td>Cocktail de pesticides dans l'alimentation : la réglementation actuelle est suffisante selon l'Efsa</td><td>141</td></tr><tr><td>Smoking during pregnancy results in an increased risk of asthma even in adulthood</td><td>142</td></tr><tr><td>Antibiotic exposure can 'prime' single-resistant bacteria to become multidrug-resistant</td><td>142</td></tr><tr><td>Breastfeeding moms' exposure to nicotine linked to infant skull defect</td><td>142</td></tr><tr><td>Dramatic loss of food plants for insects</td><td>142</td></tr><tr><td>Adsorbent material developed with PET bottles for the removal of antibiotics from water</td><td>143</td></tr><tr><td>Health impacts of pollution upon indigenous peoples</td><td>143</td></tr><tr><td>RIT scientists develop first 3D mass estimate of microplastic pollution in Lake Erie</td><td>143</td></tr><tr><td>Exposure to air pollution during pregnancy is associated with growth delays</td><td>143</td></tr><tr><td>How atrazine regulations have influenced the environment</td><td>144</td></tr><tr><td>CDC Finds Sharp Rise in Home Poisonings Tied to Disinfectant and Sanitizer Use during Covid-19 Pandemic ; Safer Products Available</td><td>144</td></tr><tr><td>Report de 3 mois du délai de commercialisation du chlorprophame (CIPC)</td><td>144</td></tr><tr><td>ZNT : Des députés dénoncent une réduction des distances d'épandage</td><td>144</td></tr><tr><td>Réduction des pesticides : les pistes du coordinateur interministériel pour vraiment changer les pratiques</td><td>145</td></tr><tr><td>Pesticides : les ONG s'attaquent aux chartes dérogeant aux distances minimales d'épandage</td><td>145</td></tr><tr><td>« Nous souhaitons structurer l'offre ecotox pour développer le marché »</td><td>145</td></tr><tr><td>Phytosanitaires : l'Anses publie la liste des substances préoccupantes à réévaluer rapidement</td><td>145</td></tr><tr><td>Faster-degrading plastic could promise cleaner seas</td><td>146</td></tr><tr><td>Princeton scientist solves air quality puzzle : Why does ozone linger long after its ban?</td><td>146</td></tr><tr><td>Study describes cocktail of pharmaceuticals in waters in Bangladesh</td><td>146</td></tr><tr><td>Green chemistry approaches to the synthesis of coumarin derivatives</td><td>146</td></tr><tr><td>Aquaculture at the crossroads of global warming and antimicrobial resistance</td><td>147</td></tr><tr><td>University of Kentucky's Superfund Research Center receives $8.7 million</td><td>147</td></tr><tr><td>MDI Biological Laboratory-led program reveals high arsenic in well water</td><td>147</td></tr><tr><td>ECOTOXicology Knowledgebase System User Guide Version 5.3</td><td>147</td></tr><tr><td>OSU research program awarded $12.7 million grant for Superfund research</td><td>148</td></tr><tr><td>Skoltech researchers find a new HIT defense bacteria use against antibiotics</td><td>148</td></tr><tr><td>Nearly half of US breathing unhealthy air ; record-breaking air pollution in nine cities</td><td>148</td></tr><tr><td>Viruses that 'turn off' plant genes could help farmers battle herbicide-resistant weeds</td><td>149</td></tr><tr><td>Thixotropie « Réduire les doses de fongicides jusque - 50 % » avec l'adjuvant 846</td><td>149</td></tr><tr><td>Protection intégrée : des solutions rentables pas toujours dispos, mais des résultats encourageants</td><td>149</td></tr><tr><td>L'encadrement des pesticides destinés aux jardiniers amateurs est précisé</td><td>149</td></tr><tr><td>Une nouvelle étude lie pollution de l'air et létalité du coronavirus</td><td>150</td></tr><tr><td>Résidus de pesticides dans les aliments : 4,5 % des échantillons dépassent la limite maximale</td><td>150</td></tr><tr><td>L'Anses propose d'identifier le résorcinol comme un perturbateur endocrinien avéré pour l'Homme</td><td>150</td></tr><tr><td>Consultations publiques suspendues : le Gouvernement déroge aux distances d'épandage de pesticides</td><td>151</td></tr><tr><td>L'IRSN fait le point sur la pollution radioactive liée aux feux de forêt à proximité de Tchernobyl</td><td>151</td></tr><tr><td>Plant protection : Communication instead of poison</td><td>151</td></tr><tr><td>Seafloor of Fram Strait is a sink for microplastic from Arctic and North Atlantic Ocean</td><td>151</td></tr><tr><td>Completely new antibiotic resistance gene has spread unnoticed to several pathogens</td><td>152</td></tr><tr><td>Mount Sinai researchers unveil mechanisms to prevent Crohn's disease</td><td>152</td></tr><tr><td>Air pollution linked to dementia and cardiovascular disease</td><td>152</td></tr><tr><td>Substances chimiques : 5 000 données de toxicité dans la base OpenFoodTox</td><td>153</td></tr><tr><td>Pesticides et abeilles : troisième round de consultation sur les lignes directrices de l'Efsa</td><td>153</td></tr><tr><td>Pharma's potential impact on water quality</td><td>153</td></tr><tr><td>26 types of microplastics and rubbers detected in Dutch rivers</td><td>153</td></tr><tr><td>Advances in genetic, geospatial techniques aid efforts to fend off invasive insects</td><td>154</td></tr><tr><td>Common anti-parasite treatments used on cattle have devastating impacts on wildlife</td><td>154</td></tr></table>
<table><tr><td>Climate and health impacts of residential wood combustion in Finland</td><td>154</td></tr><tr><td>Ancient plant genes could increase food production without added fertilizer use, mitigating deadly algal blooms</td><td>154</td></tr><tr><td>USDA produce industry committee recommends EPA suspend registration of drift-prone dicamba herbicides</td><td>154</td></tr><tr><td>Pesticide seed coatings are widespread but underreported</td><td>155</td></tr><tr><td>Phytosanitaires : la procédure à suivre lorsque la classification des produits évolue</td><td>155</td></tr><tr><td>Pulvérisation Berthoud teste le spot spraying sur des exploitations européennes</td><td>155</td></tr><tr><td>Sous quelles conditions les distances peuvent-elles être réduites ?</td><td>155</td></tr><tr><td>La société Dow AgroSciences fait appel de la décision d'annuler la mise sur le marché de deux insecticides</td><td>156</td></tr><tr><td>Pesticides : le Conseil d'État rejette les recours de la Coordination rurale sur les distances d'épandage</td><td>156</td></tr><tr><td>Produits chimiques : l'Echa lance un outil pour aider les entreprises à respecter la législation</td><td>156</td></tr><tr><td>Ile-de-France : la pollution de l'air des écoles diminue mais reste un sujet de préoccupation</td><td>156</td></tr><tr><td>Qualité de l'air dans les cours d'écoles lyonnaises : des parents et des associations saisissent la justice</td><td>157</td></tr><tr><td>Natural organic matter influences arsenic release into groundwater</td><td>157</td></tr><tr><td>Microplastics affect the survival of amphibians and invertebrates in river ecosystems</td><td>157</td></tr><tr><td>New findings of chemical differences between PM1 and PM2.5 might reshape air pollution studies</td><td>157</td></tr><tr><td>Pesticides increase the risk of schistosomiasis, a tropical disease</td><td>158</td></tr><tr><td>Air pollution is one of the world's most dangerous health risks</td><td>158</td></tr><tr><td>Des pesticides, oui, mais des bio !</td><td>158</td></tr><tr><td>EU neonic insecticide ban cut UK canola production from 1.8 million acres to 1.3 million annually</td><td>158</td></tr><tr><td>Will legal 'assault' on Bayer's Roundup weedkiller in US, EU threaten Africa's access to glyphosate ?</td><td>159</td></tr><tr><td>Pollution au chlordécone : Des associations réclament l'ouverture d'une nouvelle enquête aux Antilles</td><td>159</td></tr><tr><td>Household Chemical Usage Related to Language Delays Among Kids</td><td>159</td></tr><tr><td>Health Canada to ban strychnine to kill Richardson's ground squirrels</td><td>159</td></tr><tr><td>Africa must act on pesticide 'double standards'</td><td>159</td></tr><tr><td>Nitrate problem worsening in rural Minnesota's drinking water</td><td>160</td></tr><tr><td>Nine Delhi districts had contaminated groundwater in 2019 : Jal Shakti Minister</td><td>160</td></tr><tr><td>It's not just chlorinated chicken: five foods a US trade deal could bring to the UK</td><td>160</td></tr><tr><td>Over quarter of city receiving chemical-laced water supply</td><td>161</td></tr><tr><td>Filière CRC Premières céréales certifiées sans résidus de produits phytos pour 2021</td><td>161</td></tr><tr><td>26e RDV agri « Protéger les plantes, mais aussi la santé humaine et l'environnement »</td><td>161</td></tr><tr><td>Pollution plastique : un guide pour limiter les fuites tout au long de la chaîne de valeur</td><td>162</td></tr><tr><td>Le taux de la taxe sur la vente de pesticides augmente à 0,9 % du chiffre d'affaires</td><td>162</td></tr><tr><td>Un Atlas dresse un panorama de la contamination au plastique</td><td>162</td></tr><tr><td>Plastiques : 14 États et 40 entreprises signent un pacte européen pour réduire la pollution</td><td>162</td></tr><tr><td>How pest management strategies affect the bottom line</td><td>163</td></tr></table>
# La règlementation sur les ressources génétiques : quelles conséquences pour les recherches en écotoxicologie ?

Depuis 1992 et l'adoption de la Convention sur la Diversité Biologique (CDB), les questions de la conservation de la diversité biologique, de l'utilisation durable de ses composantes et du partage juste et équitable des avantages découlant de l'utilisation de ressources génétiques (RG) sont posées. Les RG prises en compte par la CDB comprennent tout matériel d'origine végétale, animale, microbienne ou autre, contenant des unités fonctionnelles de l'hérédité, ayant une valeur effective ou potentielle (à l'exception notamment des RG Humaines). Les RG s'étendent également aux produits dérivés que sont tous les composés biochimiques qui existent à l'état naturel résultant de l'expression génétique ou du métabolisme de ressources biologiques ou génétiques (par exemple des protéines). Enfin, la réglementation s'applique également aux connaissances traditionnelles associées (CTA) aux RG qui sont les « connaissances, innovations et pratiques » qui « incarnent des modes de vie traditionnels présentant un intérêt pour la conservation et l'utilisation durable de la diversité biologique ».

La CDB réaffirme la souveraineté des États sur leurs RG, et contient des engagements de leur part à coopérer et assurer la conservation et l'utilisation durable de la biodiversité, le partage des avantages issus de l'utilisation de connaissances traditionnelles des communautés locales et autochtones, et le respect des droits de propriété intellectuelle sur les innovations biotechnologiques. Les Etats doivent en outre faciliter l'accès aux ressources génétiques aux fins d'utilisation « écologiquement rationnelle ».

La CDB a conduit à la mise en place d'un mécanisme qui encadre la relation entre fournisseurs et utilisateurs de RG, dénommé APA ou « Accès aux ressources génétiques (et aux connaissances traditionnelles associées) et Partage juste et équitable des Avantages découlant de leur utilisation » (ou en anglais *Access and Benefit-Sharing – ABS*). Le Protocole de Nagoya, adopté lors de la conférence des parties (COP) de la CDB du 10 d'octobre 2010, et entré en vigueur en 2014, en précise les dispositions et le cadre réglementaire afin de sécuriser l'APA au plan juridique.

## Le mécanisme de l'APA en quelques lignes

L'APA repose sur une relation bilatérale entre un Etat (ou une communauté autochtone et locale) fournisseur d'une RG (ou d'une CTA), et un utilisateur qui a l'intention de mener des travaux de recherche et de développement (R&D). L'accès à la ressource requiert le consentement préalable en connaissance de cause (CPCC ou *Prior Informed Consens Consent - PIC*) de l'État fournisseur (sauf si la législation de ce pays n'exige pas un tel accord), dans des conditions convenues d'un commun accord (CCCA ou *Mutually Agreed Terms - MAT*). Ces CCCA fixent le partage des avantages découlant de l'utilisation des RG ou CTA, c'est-à-dire les contreparties demandées par l'État fournisseur de la RG/CTA. Les avantages peuvent être monétaires (royalties...) ou non monétaires (transfert de technologies, partage de connaissances...).

Chaque Partie au protocole de Nagoya s'engage à mettre en place des dispositifs réglementaires pour définir les modalités d'accès aux RG/CTA relevant de sa souveraineté, le partage des avantages liés à l'accès et l'utilisation de ces RG/CTA, et à mettre en place les mesures destinées à s'assurer que l'utilisation de RG/CTA sous sa juridiction est conforme aux règles d'APA du pays fournisseur, notamment avec des points de contrôle.
Chaque Partie au protocole doit désigner une Autorité Nationale Compétente (ANC), qui reçoit les déclarations, délivre les autorisations, émet les permis internationaux, et un point focal qui informe les utilisateurs sur les exigences de son pays en matière d'APA.

Le protocole de Nagoya crée un centre d'échange sur l'APA (ABS clearing house = ABS CH). Chaque Partie lui transmet les informations pertinentes la concernant (réglementation, permis délivrés...). L'ABS CH édite et publie les certificats de conformité reconnus à l'échelle internationale (IRCC) sur la base des informations transmises par les Parties.

A noter que les RG humaines et, jusqu'à présent, les RG de haute mer (hors de toute juridiction nationale), sont exclues du champ d'application du protocole de Nagoya. Par ailleurs, le protocole ne s'applique pas aux instruments internationaux d'APA déjà existants ou à venir, ayant les mêmes objectifs que la CDB et le protocole. C'est le cas, à ce jour, du Traité International sur les Ressources phytogénétiques pour l'Alimentation et l'Agriculture (TIRPAA) et du cadre de préparation de l'OMS en cas de grippe pandémique (WHO Pandemic Influenza Preparedness Framework).

Si la mise en application de l'APA concerne en premier lieu les échanges internationaux de RG et les Centres de Ressources Biologiques qui les conservent et les distribuent, celle-ci peut impacter les recherches dans le champ de l'écotoxicologie, y compris dans le cadre de programmes nationaux.

## Le cadre législatif et règlementaire de l'APA

Outre la CDB et le protocole de Nagoya au niveau international, le cadre règlementaire comprend un niveau européen, l'Union Européenne étant Partie au protocole, et un niveau français.

* **Au niveau européen**, trois textes précisent les modalités de l'APA. Ils portent sur la conformité de l'utilisation de ressources génétiques, dans l'Union, aux règles d'APA :

- Le règlement UE N°511/2014 du Parlement européen et du Conseil relatif aux mesures concernant le respect par les utilisateurs dans l'Union du protocole de Nagoya sur l'accès aux ressources génétiques et le partage juste et équitable des avantages découlant de leur utilisation.

- Son règlement d'exécution 2015/1866 du 13 octobre 2015 portant modalités d'application du règlement UE N°511/2014 du Parlement européen et du Conseil en ce qui concerne le registre des collections, la surveillance du respect des règles par l'utilisateur et les bonnes pratiques.

- Le document d'orientation sur le champ d'application et les obligations essentielles du règlement UE N°511/2014 du Parlement européen et du Conseil.

Ainsi, les utilisateurs de RG ont obligation de diligence : ils doivent « faire preuve de la diligence nécessaire afin de s'assurer que l'accès aux ressources génétiques et aux connaissances traditionnelles associées aux ressources génétiques qu'ils utilisent s'est effectué conformément aux dispositions législatives ou réglementaires applicables en matière d'accès et de partage équitable des avantages, et que les avantages font l'objet d'un partage juste et équitable selon des conditions convenues d'un commun accord, conformément à toute disposition législative ou réglementaire applicable ».

* **Au niveau français**, l'APA est principalement encadrée par :

- La loi N°2016-1087 du 8 août 2016 pour la reconquête de la biodiversité, de la nature et des paysages.

- Le décret N°2017-848 du 9 mai 2017 relatif à l'accès aux ressources génétiques et aux connaissances traditionnelles associées et au partage des avantages découlant de leur utilisation.

La réglementation française concerne l'accès aux RG/CTA prélevées sur le territoire national (métropole et DROM) ainsi que la conformité de l'utilisation de RG/CTA collectées sur le territoire national ou à l'étranger. A noter qu'il existe pour certaines ressources des régimes spécifiques qui les placent hors champ des procédures de l'APA.
Sont exclues du champ d'application de la réglementation nationale : les RG humaines, les RG relevant du TIRPAA, les RG des espèces utilisées comme modèles dans la R&D (définies par *arrêté*), les CTA ne pouvant être attribuées à une ou plusieurs communautés d'habitants ou déjà bien connues, les RG échangées pour l'usage personnel ou au sein des communautés d'habitants entre elles, et enfin la R&D concourant à la sauvegarde des intérêts de la défense et de la sécurité nationale.

La réglementation définit un régime général avec obligation de déclaration pour la recherche fondamentale et demande d'autorisation pour la recherche ayant un objectif de valorisation, et des régimes spécifiques :

* RG végétales cultivées ou animales domestiquées, espèces végétales sauvages apparentées, RG objets de sylviculture, RG collectées par les laboratoires pour la prévention et la lutte contre les dangers sanitaires et pour la sécurité sanitaire des aliments (au sens du code rural et de la pêche maritime), RG collectées par les laboratoires pour la prévention et la maîtrise des risques graves pour la santé humaine, RG micro-organismes domestiqués et cultivés.

* Les RG des micro-organismes prélevés sur le territoire métropolitain sont exemptées des procédures APA pendant 3 ans jusqu'au 2 septembre 2022 (loi PACTE), mais en contrepartie il faut répondre à une enquête du MTES chaque année.

Les RG contenues dans des échantillons prélevés dans l'environnement découlent chacune de leur régime respectif.

**La loi désigne le MTES comme point focal national, comme autorité compétente pour les déclarations aux RG et les demandes d'autorisations d'accès aux RG et CTA, ainsi que pour la déclaration de diligence nécessaire au stade du développement final d'un produit.**

Le MESRI est autorité compétente pour la déclaration de diligence nécessaire au stade de financement des projets de recherche et pour les demandes d'inscription des collections au registre européen.

Enfin, les Provinces de Nouvelle-Calédonie et la Polynésie française sont autorités compétentes sur leurs territoires respectifs.

**Tous les organismes de recherche et chercheurs français sont soumis, depuis 2017, à l'ensemble de ces textes !**

Le non-respect des procédures APA est passible de sanction. Si les instituts de recherche et universités sont des personnes morales directement passibles de sanctions, leurs personnels reconnus responsables de mauvaise pratiques peuvent être condamnés au civil et au pénal (jusqu'à un an d'emprisonnement et 150 000 € d'amende, portée à 1 M€ en cas d'utilisation commerciale). En outre leur image et leur réputation (reconnaissance de bio-piratage) seront très fortement dégradées avec un impact important sur les partenariats, des difficultés en vue de l'obtention de permis de recherche/autorisations pour l'accès aux ressources, le remboursement des aides publiques perçues, une méfiance dans les négociations contractuelles, une perte de certifications/labellisations pour leurs outils, un risque de se voir refuser la publication d'articles par les éditeurs scientifiques...

Il ne faut pas oublier dans la mise en œuvre des projets de recherche les autres règlementations en vigueur concernant : la propriété des échantillons, les contraintes associées aux matériels de quarantaine, le respect des données personnelles (CNIL, RGPD...), l'open science, ainsi que les exigences des financeurs (ANR...)...
## Comment la règlementation APA impacte-t-elle les travaux de recherche en écotoxicologie ?

La règlementation APA concerne toute personne physique ou morale, française ou étrangère et travaillant pour le secteur public ou privé, qui utilise des RG (ou dérivés) pour des activités de R&D sur la composition génétique ou biochimique des RG, notamment par l'application de la biotechnologie, y compris pour la valorisation de ces RG, les applications et la commercialisation qui en découlent, ainsi que des CTA correspondant à leur étude et à leur valorisation.

* **Les programmes de recherche menés directement par les chercheurs des unités de recherche**, qui portent sur l'évaluation des effets biologiques des contaminants chimiques sur les organismes de l'environnement, sont concernés, dès lors que sont impliqués :

* ✓ Des échantillons prélevés dans les milieux naturels (sols, eaux, air) visant une utilisation de leur biote, par exemple des travaux portant sur l'abondance, la diversité et l'activité des organismes,

* ✓ Des prélèvements en vue de la mise en place d'élevages (par exemples arthropodes...) au laboratoire,

* ✓ Des échantillons acquis auprès de collections tierces, qui, tous, renferment des RG !

Il convient d'examiner, au cas par cas, quelle est l'origine de la RG, la date de sa collecte (les textes ne sont pas rétroactifs), quelles sont la traçabilité, les informations et la documentation associées à chaque échantillon, quel régime s'applique à la RG en cas de collecte sur le territoire national.

Des outils sont disponibles pour aider à décortiquer les différentes situations (lien autodiagnostic sur le sharepoint APA [intranet INRAE]().

* **Lorsque les programmes de recherche s'appuient sur des CRBs et collections** (par exemple ceux du pilier Environnement BRC4Env de l'IR AgroBRC-RARe), les gestionnaires des CRBs et collections doivent également se poser ces questions avant tout transfert de RG à un utilisateur, et déterminer s'ils sont en mesure de transférer toutes les informations et tous les documents requis (consulter là encore le sharepoint APA [intranet INRAE].)

Les CRB ont la possibilité de se faire inscrire au registre des collections de l'UE :

https://ec.europa.eu/environment/nature/biodiversity/international/abs/pdf/Register of Collections.pdf.

* ✓ **Avantages** : visibilité au niveau européen et international, solide réputation de sérieux auprès de la communauté scientifique et notamment des utilisateurs potentiels, représente un point d'appui pour les futurs projets car lorsqu'il se procure une RG auprès d'une collection inscrite au registre européen, l'utilisateur est réputé avoir fait preuve de diligence nécessaire en ce qui concerne l'obtention de toutes les informations et documents relatifs à la RG ce qui représente pour lui une simplification, une sécurité et un gain de temps notoires.

* ✓ **Contraintes** : adaptation du système d'information, analyse du statut des RG de la collection vis-à-vis de l'APA, investissement humain pour le montage du dossier, adaptation du système qualité.

## Les recherches en écotoxicologie et l'APA : quelle conduite adopter ?

Lors de la réflexion préalable à la construction d'un projet de recherche en écotoxicologie, puis de sa mise en œuvre, il convient de s'interroger sur les points suivants.

* **Pour les projets utilisant des RG prélevées en France** :

* ✓ Tout d'abord vérifier si la RG (ou CTA) utilisée est soumise à un régime d'APA, selon sa nature, l'origine, la date d'accès, et l'utilisation qui en est faite.

* ✓ Le cas échéant, vérifier quelle procédure règlementaire sera à mettre en œuvre : par exemple déclaration ou autorisation pour les échantillons prélevés sur le territoire national (sauf pour la Nouvelle-Calédonie et la Polynésie française qui ont leurs propres réglementations).

**La signature des procédures de déclaration** relève de la compétence des directeurs d'unité (pour INRAE). Elle s'applique dans les cas de l'utilisation de RG à des fins de connaissance sur la biodiversité, de conservation en collection ou de valorisation sans objectif direct de développement commercial,
en situation d'urgence relative à la santé humaine, à la santé animale ou à la santé végétale. Les détenteurs de collections scientifiques peuvent, à leur demande, bénéficier d'une procédure de déclaration annuelle simplifiée.

https://www.demarches-simplifiees.fr/commencer/apa-declaration-pmorale

La signature des procédures d'autorisation relève de la compétence des **présidents de centres** (pour INRAE). Elle concerne toutes les autres utilisations de ressources génétiques et notamment avec un objectif direct de développement commercial, ainsi que l'utilisation de connaissances traditionnelles associées. L'autorisation précise les conditions d'utilisation des RG et des CT associées et les conditions de partage des avantages dans une convention entre demandeur et ANC. Le délai d'instruction est de 2 mois à compter de l'accord sur le partage des avantages entre le demandeur et l'ANC. Le refus doit être motivé.

https://www.demarches-simplifiees.fr/commencer/apa-autorisation-pmorale

* **Pour les projets de recherche utilisant des RG prélevées dans des pays de l'UE ou d'autres pays tiers :**

* ✓ Vérifier si le pays est Partie au protocole de Nagoya, et consulter sa réglementation APA en vigueur.

* ✓ Eventuellement préciser la répartition des démarches entre partenaires.

* **Pour tous les projets :** il sera sans doute nécessaire en cours de projet, si le protocole de Nagoya et la réglementation européenne s'appliquent et en fonction de la date d'accès à la RG, de faire preuve de diligence nécessaire : déclaration de due diligence et transmission du récépissé au financeur (ou INPI ou autorité compétente pour la mise sur le marché, selon le cas, s'il y a valorisation commerciale).

## Où trouver les informations pratiques ?

* **Au sein d'INRAE, le site intranet APA** https://sites.inra.fr/site/maj/APA fournit de nombreuses ressources et outils pratiques notamment un autodiagnostic, des arbres de décision, une base pays, les démarches APA à INRAE, une FAQ, des liens utiles... qui vous guideront pour la gestion de l'APA dans les projets de recherche et lors de transferts d'échantillons. La cellule APA apa@inrae.fr peut également être contactée si ces outils ne vous permettent pas de réaliser les démarches adéquates. La NS 2019-66 précise également les modalités d'instruction, de gestion et de suivi des dossiers de déclaration et d'autorisation administrative pour l'accès aux ressources génétiques et aux connaissances traditionnelles qui leur sont associées en vue de leur utilisation.

* **En dehors d'INRAE, les scientifiques doivent se rapprocher de leur ANC et/ou de leur cellule APA institutionnelle.**

## En conclusion, l'APA : contrainte ou opportunité ?

Les principes de l'APA visent à préserver la biodiversité. Ils s'appliquent à l'accès et à l'utilisation des RG (et produits dérivés) ainsi qu'aux connaissances traditionnelles associées aux ressources génétiques. Le protocole de Nagoya établit des mécanismes pour mettre en œuvre l'APA, sur la base d'accords bilatéraux. Ils offrent au fournisseur et à l'utilisateur de ressources génétiques et CTA une sécurité juridique. Les États élaborent et mettent en œuvre des réglementations nationales en matière d'APA. Tous les utilisateurs de RG doivent se conformer à ces réglementations. Malgré des contraintes évidentes, le protocole de Nagoya doit être considéré comme une opportunité d'améliorer les pratiques de recherche et de partenariat, en impliquant réellement tous les porteurs d'enjeux, et en reconnaissant leurs droits et devoirs. Les institutions ont mis en place les structures et outils d'accompagnement à la mise en œuvre de l'APA. Le projet ABS4BRCs diffusera prochainement via son site internet (à venir) un certain nombre de documents utiles.
## Contacts

* Cellule APA INRAE : Didier Bouchel et Micaël Aliouat

* Pilier Environnement BRC4ENv de l'IR RARe, Plateforme Biochem-Env : Christian Mougin

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## Pour en savoir plus

* **Sites web**

- ABSCH : https://absch.cbd.int/

- FAO : http://www.fao.org/plant-treaty/areas-of-work/the-multilateral-system/overview/fr/

- BDD : https://ssl.fao.org/glis/entity/search ; https://www.genesys-pgr.org/

- Europe : https://ec.europa.eu/environment/nature/biodiversity/international/abs/

- MESRI : https://www.enseignementsup-recherche.gouv.fr/pid37627/utilisation-de-ressources-genetiques-ou-de-connaissances-traditionnelles-associees.html

- INRAE sharepoint APA : https://sites.inra.fr/site/maj/APA/

- ABS4BRCs : projet-abs4brcs.fr (à venir)

* **Guides**

- APA pas à pas : https://www.fondationbiodiversite.fr/lapa-pas-a-pas/

- Code de conduite et le guide des bonnes pratiques du « Consortium of European Taxonomic Facilities » : https://cetaf.org/services/natural-science-collections-and-access-and-benefit-sharing

* **Autres**

- Document d'orientation sur le champ d'application et les obligations essentielles du règlement (UE) no 511/2014 : https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:32014R0511

- Arrêté sur les espèces modèles : https://cache.media.enseignementsup-recherche.gouv.fr/file/Encadrement_des_pratiques_de_recherche/86/2/Liste_especes_modeles_1191862.pdf

- INRAE NS 2019-66 : Instruction, gestion et suivi des dossiers de déclaration et d'autorisation administrative pour l'accès aux ressources génétiques et aux connaissances traditionnelles qui leur sont associées en vue de leur utilisation.
Mechanism of lead
bioaccumulation by
freshwater algae in the
presence of organic acids

Authors: Que WY, Wang BH, Li FL, Chen XJ, Jin H, Jin ZF

Source: CHEMICAL GEOLOGY 540:UNSP 119565, 2020, DOI: 10.1016/j.chemgeo.2020.119565

**Abstract:** The accumulation of heavy metals by freshwater algae becomes more complex in the presence of dissolved organic matter but it is unclear how and to what extent. In this study, we comparatively assessed the effects of malic acid and citric acid on the bioaccumulation of Pb by Chlorella pyrenoidosa. A 6 h exposure experiment showed that adding organic acid (OA) to an algae-Pb binary system prolonged the adsorption equilibrium time and that the extended time was related to the concentration and number of carboxyl groups of the OA. A pseudo-second-order model fit the kinetic data well in the presence of OAs. The normality of carboxyl groups was negatively correlated with the bioaccumulation rate, k(2), but positively correlated with the maximum bioaccumulation capacity, q(max), of Pb following a linear equation, Y = 121.3x + 52.2, R² = 0.9877. Neither the Freundlich model nor the Langmuir model could fit the isotherm data in the presence of OA, suggesting that a new mechanism might exist. The quantitative relationship between bioaccumulated Pb and carboxyl group of OA indicated a stoichiometric relationship, which seemed to support the theory of a ternary complex of Pb, OA, and algal surface. Our results have added clarity to the current understanding of the accumulation of heavy metals by algae in freshwater ecosystems.

Accès au document

Age-related physicochemical
differences in ZnO
nanoparticles in the seawater
and their bacterial
interaction

Authors: Baysal A, Saygin H, Ustabasi GS

Source: ENVIRONMENTAL MONITORING AND ASSESSMENT 192(5):276, 2020, DOI: 10.1007/s10661-020-08254-w

**Abstract:** To assess the fate and behavior of engineered nanoparticles in the environment, it is important to examine the physicochemical and toxicological transformation of nanoparticles as they age in seawater. In this study, we investigated how aging and seawater conditions altered the physicochemical structure of nanoparticles and affected their interactions with bacteria. For this purpose, zinc oxide nanoparticles were aged under different seawater conditions by keeping them in 1%, 10%, and 100% seawater for 1 day and 20 days. The main physicochemical parameters (surface chemistry, chemical composition, particle size, and zeta potential) and toxicity of aged nanoparticles towards gram-negative *Pseudomonas aeruginosa* and gram-positive *Staphylococcus aureus* were examined. The results indicated that aged zinc oxide nanoparticles in various concentrations of seawater changed their surface chemistry, chemical composition, particle size, and zeta potentials. Growth inhibition results were observed in that the inhibition of gram-negative (*Pseudomonas aeruginosa*) bacteria was higher compared with the gram-positive (*Staphylococcus aureus*) bacteria, and *Staphylococcus aureus* activated with the aged zinc oxide nanoparticles. Also, the results showed that the key biochemical factors affected by the aging and seawater concentration.

Accès au document
# Biofilms grown in aquatic microcosms affect mercury and selenium accumulation in *Daphnia*

**Authors:** Issa S, Ciesielski TM, Mikkelsen Ø, Einum S, Jaspers VLB

**Source:** ECOTOXICOLOGY 29: 485-492, 2020, doi: 10.1007/s10646-020-02194-4

**Abstract:** Experiments examining mercury (Hg) toxicity in Daphnia are usually conducted in highly standardized conditions that prevent the formation of biofilm. Although such standardization has many advantages, extrapolation of results to natural conditions and inference of ecological effects is challenging. This is especially true since biofilms can accumulate metals/metalloids and play a key role in their transfer to higher trophic level organisms. In this study, we experimentally tested the effects of spontaneously appearing biofilm in Daphnia cultures on accumulation of Hg and its natural antagonist selenium (Se) in Daphnia magna. We added Hg (in the form of mercury (II) chloride) at two concentrations (0.2 µg/L and 2 µg/L) to experimental microcosms and measured the uptake of Hg and Se by D. magna in the presence and absence of biofilm. To test for consistent and replicable results, we ran two identical experimental sets one week apart. Biofilm presence significantly reduced the accumulation of Hg, while increasing the tissue Se content in D. magna, and these findings were reproducible across experimental sets. These findings indicate that highly standardized tests may not be adequate to predict the bioaccumulation and potential toxicity of metals/metalloids under natural conditions.

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# Portable Microalgal Biosensor for Herbicide Monitoring

**Authors:** Boronl, Juarez A, Battaglini F

**Source:** CHEMELECTROCHEM 7(7):1623-1630, 2020, DOI: 10.1002/celc.202000210

**Abstract:** The need for in-situ and real-time tools to monitor the fate of pesticides in extensive areas is of great concern to preserve the environment in countries where agroindustry

represents an essential part of its economy. In this work, we present the construction of a portable system based on the reversible photosynthesis inhibition produced by herbicides on microalgae, using atrazine as a model compound. The decrease in oxygen production due to the photosynthesis inhibition is electrochemically detected using an automated flow system. The system presented here involves the immobilization of microalgae in a polyelectrolyte-surfactant-carbon nanotube self-assembled material cast on a screen-printed graphite electrode; these components contribute to the stability and sensitivity of the whole device. The system presents a limit of detection of 0.11 µM, showing an excellent performance in river samples. The sensor maintains its integrity after five months immersed in a freshwater algae medium at room temperature. These features are key to install this system along the course of a river at a low cost, allowing early detection of polluted areas and long term environmental studies.

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# Enhanced production of laccase from gamma irradiated endophytic fungus: A study on biotransformation kinetics of aniline blue and textile effluent decolourisation

**Authors:** Navada KK, Kulal A

**Source:** JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING 8(2):UNSP 103550, 2020, DOI: 10.1016/j.jece.2019.103550

**Abstract:** Managing triphenylmethane class of dyes such as aniline blue present in the effluents is a nightmare for the industries and environmentalists. There are physical and chemical approaches available for degrading these recalcitrant dyes. However, these methods become expensive process and also degraded products are not ecofriendly in nature. Laccase from white rot fungi had been used for biotransformation of triphenylmethane class of dyes except for aniline blue. This study focussed on laccase from gamma irradiated endophytic fungus (Phomopsis sp.) and its enhanced activity
in degrading aniline blue as well as textile dye effluent. Laccase production was increased in 1.2 kGy gamma irradiated endophytic fungus (2 fold) and hence dye degradation was enhanced when compared to the non-irradiated (wild) fungus. The laccase activity exhibited appreciable stability for metal ions (Zn2+, Cu2+, Cr2+ and Ca2+) up to 10 mM concentration. The highest laccase activity and dye decolourisation rate was observed around 30 degrees C temperature at pH 5. The degraded intermediates were identified and a mechanism of degradation was proposed based on UV-vis, FTIR and LC-MS analysis. The aniline blue degradation kinetics strictly followed Michaelis-Menten model. The degraded aniline blue dye samples had reduced COD and were non-toxic to plants and microorganisms. To substantiate the industrial application, textile effluent was treated with laccase from the endophytic fungus and found 99 % decolourisation within 2.5 h. There was a 67 % reduction in COD and a 47 % reduction in BOD in laccase mediated textile effluent treatment.

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## The combined toxicity influence of microplastics and nonylphenol on microalgae *Chlorella pyrenoidosa*

**Authors:** Yang WF, Gao XX, Wu YX, Wan L, Tan LC, Yuan SM, Ding HJ, Zhang WH

**Source:** ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 195:110484, 2020, DOI: 10.1016/j.ecoenv.2020.110484

**Abstract:** Microplastics and nonylphenol (NP) are considered as emerging pollutant and have attracted wide attention, while their combined toxicity on aquatic organisms is barely researched. Therefore, the combined toxicity influence of NP with three types of microplastics containing polyethylene (PE1000, 13 µm and PE, 150 µm), polyamide (PA1000, 13 µm and PA, 150 µm) polystyrene (PS, 150 µm) on microalgae Chlorella pyrenoidosa was analyzed. Both growth inhibition, chlorophyll fluorescence, superoxide dismutase (SOD), malondialdehyde (MDA), and catalase (CAT) were determined. We found that single microplastics and NP both inhibited algal growth, thereby causing oxidative stress. The order of inhibition effect in single microplastics experiment was PE1000 &#62; PA1000 &#62; PE approximate to PS &#62; PA. The combined

toxicity experiment results indicated that the presence of microplastics had positive effect in terms of alleviating NP toxicity to C. pyrenoidosa, and the microplastics adsorption capacity to NP was the dominant contributing factor for this effect. According to the independent action model, the combined toxicity was antagonistic. Because the negative effect of smaller size microplastics on algal growth was aggravated with prolonged exposure time, the optimum effect of microplastics alleviated NP toxicity was PA1000 at 48 h, while this effect was substituted by PA at 96 h during combined toxicity. Thus, the toxicity of smaller size microplastics has a nonnegligible influence on combined toxicity. This study confirms that microplastics significantly affected the toxicity of organic pollutants on microalgae. Further research on the combined toxicity of smaller size microplastics with pollutants in chronic toxicity is needed.

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## Insights Into the Biodegradation of Lindane (gamma-Hexachlorocyclohexane) Using a Microbial System

**Authors:** Zhang WP, Lin ZQ, Pang SM, Bhatt P, Chen SH

**Source:** FRONTIERS IN MICROBIOLOGY 11:522, 2020, DOI: 10.3389/fmicb.2020.00522

**Abstract:** Lindane (gamma-hexachlorocyclohexane) is an organochlorine pesticide that has been widely used in agriculture over the last seven decades. The increasing residues of lindane in soil and water environments are toxic to humans and other organisms. Large-scale applications and residual toxicity in the environment require urgent lindane removal. Microbes, particularly Gram-negative bacteria, can transform lindane into non-toxic and environmentally safe metabolites. Aerobic and anaerobic microorganisms follow different metabolic pathways to degrade lindane. A variety of enzymes participate in lindane degradation pathways, including dehydrochlorinase (LinA), dehalogenase (LinB), dehydrogenase (LinC), and reductive dechlorinase (LinD). However, a limited number of reviews have been published regarding the biodegradation and bioremediation of
lindane. This review summarizes the current knowledge regarding lindane-degrading microbes along with biodegradation mechanisms, metabolic pathways, and the microbial remediation of lindane-contaminated environments. The prospects of novel bioremediation technologies to provide insight between laboratory cultures and large-scale applications are also discussed. This review provides a theoretical foundation and practical basis to use lindane-degrading microorganisms for bioremediation.

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## Comparison of the Level and Mechanisms of Toxicity of Carbon Nanotubes, Carbon Nanofibers, and Silicon Nanotubes in Bioassay with Four Marine Microalgae

**Authors:** Pikula K, Chaika V, Zakharenko A, Markina Z, Vedyagin A, Kuznetsov V, Gusev A, Park S, Golokhvast K

**Source:** NANOMATERIALS 10(3):485, 2020, DOI: 10.3390/nano10030485

**Abstract:** Nanoparticles (NPs) have various applications in medicine, cosmetics, optics, catalysis, environmental purification, and other areas nowadays. With an increasing annual production of NPs, the risks of their harmful influence to the environment and human health is rising. Currently, our knowledge about the mechanisms of interaction between NPs and living organisms is limited. Additionally, poor understanding of how physical and chemical characteristic and different conditions influence the toxicity of NPs restrict our attempts to develop the standards and regulations which might allow us to maintain safe living conditions. The marine species and their habitat environment are under continuous stress due to anthropogenic activities which result in the appearance of NPs in the aquatic environment. Our study aimed to evaluate and compare biochemical effects caused by the influence of different types of carbon nanotubes, carbon nanofibers, and silica nanotubes on four marine microalgae species. We evaluated the changes in growth-rate, esterase activity, membrane polarization, and size changes of microalgae cells using flow cytometry method. Our results demonstrated that toxic effects

caused by the carbon nanotubes strongly correlated with the content of heavy metal impurities in the NPs. More hydrophobic carbon NPs with less ordered structure had a higher impact on the red microalgae P. purpureum because of higher adherence between the particles and mucous covering of the algae. Silica NPs caused significant inhibition of microalgae growth-rate predominantly produced by mechanical influence.

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## Co-metabolism of sulfamethoxazole by a freshwater microalga *Chlorella pyrenoidosa*

**Authors:** Xiong Q, Liu YS, Hu LX, Shi ZQ, Cai WW, He LY, Ying GG

**Source:** WATER RESEARCH 175:115656, 2020, DOI: 10.1016/j.watres.2020.115656

**Abstract:** Microalgae-mediated biodegradation of antibiotics has recently gained increased attention from international scientific community. However, limited information is available regarding microalgae-mediated biodegradation of SMX in a co-metabolic system. Here we investigated the biodegradation of sulfamethoxazole (SMX) by five algal species (*Pseudokirchneriella subcapitata*, *Scenedesmus quadricauda*, *Scenedesmus obliquus*, *Scenedesmus acuminatus* and *Chlorella pyrenoidosa*), and its transformation pathways by *C. pyrenoidosa* in a sodium acetate (3 mM) co-metabolic system. The results showed that the highest SMX dissipation (14.9%) was detected by *C. pyrenoidosa* after 11 days of cultivation among the five tested algal species in the absence of other carbon sources. The addition of sodium acetate (0-8 mM) significantly enhanced the dissipation efficiency of SMX (0.4 µM) from 6.05% to 99.3% by *C. pyrenoidosa* after 5 days of cultivation, and the dissipation of SMX followed the first-order kinetic model with apparent rate constants (k) ranging from 0.0107 to 0.9811 d⁻¹. Based on the results of mass balance analysis, biodegradation by *C. pyrenoidosa* was the main mechanism for the dissipation of SMX in the culture medium. Fifteen phase I and phase II metabolites were identified, and subsequently the transformation pathway was proposed, including oxidation, hydroxylation, formylation
and side chain breakdown, as well as pterin-
related conjugation. The majority of metabolites
of SMX were only observed in the culture medium
and varied with cultivation time. The findings of
the present study showed effective co-
metabolism of a sulfonamide by microalgae, and
it may be applied in the aquatic environment
remediation and wastewater treatment in the
future.

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Treatment enhances the
prevalence of antibiotic-
resistant bacteria and
antibiotic resistance genes in
the wastewater of Sri Lanka,
and India

Authors: Kumar M, Ram B, Sewwandi H, Sulfikar, Honda R, Chaminda T

Source: ENVIRONMENTAL RESEARCH 183:109179, 2020, DOI: 10.1016/j.envres.2020.109179

Abstract: Wastewater treatment plants (WWTPs) are being debated for being the hot spots for the development of antibiotic resistance in pathogenic microbial communities. We observed the prevalence of antibiotic-resistant bacteria (ARB), antibiotic resistance genes (ARG), and multidrug resistance (MDR) in two municipal WWTPs and one hospital WWTP in Western and Southern Sri Lanka, and compared the results with particular reference to Indian and the World scenario to trace the imprints of treatment on ARB and ARG. Result suggests that although wastewater treatment resulted in higher than 1.06 log Escherichia coli (E. coli) reduction at all WWTPs, yet the percent of E. coli resistant to most of the antibiotics increased from influent to effluent. Higher prevalence of ARB, ARG, and MDR were noted in hospital WWTP owing to the higher antibiotic concentrations used and excreted by the patients. With reference to India, the WWTPs in Sri Lanka showed more ARB and a consistent increase in its percentages after the treatment but were less resistant to Fluoroquinolone (FQ). E. coli strains isolated from each location of both countries showed multidrug resistance, which has increased after the treatment and was strongly correlated with FQ in every WWTP. Resistant genes for Fluoroquinolone (FQ) (aac(6')-1b-cr, qnrB, qnrS), beta-lactams (ampC), and

sulphonamides (sul1) were common in all the
wastewaters except additional parC gene in the
hospital effluent of Sri Lanka, implying much
higher resistance for quinolones, especially for
Ciprofloxacin. Multivariate statistical treatments
suggest that effluent showed higher loadings and
association for MDR/ARB, where pH change and
more extensive interaction with metals during the
treatment processes seem to have profound
effects.

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Phytochemical Compounds as
Cleaning Agents on Granite
Colonized by Phototrophic
Subaerial Biofilms

Authors: Genova C, Fuentes E, Sanmartin P, Favero G, Prieto B

Source: COATINGS 10(3): 295, 2020, DOI: 10.3390/coatings10030295

Abstract: The society has become increasingly interested in using natural products over chemicals for cleaning activities. In this study, the cleaning potential of formulations embedded in a hydrogel matrix and composed respectively of essential oils (EOs) of *Origanum vulgare*, *Thymus vulgaris*, and *Calamintha nepeta*, and their respective main active components (EO-ACs), viz., Carvacrol, Thymol, and Pulegone, on a phototropic biofilm growing on granite was investigated. In addition, and for comparative purposes, analysis with the combination of the three EOs, the combination of the three EO-ACs, and Preventol RI-80 (R) (one of the most effective commercial cleaning agents based on quaternary ammonium salts) in all three cases embedded in a hydrogel matrix, as well as only the hydrogel matrix, distilled water, and Preventol RI-80 (R), in both latter cases applied with brush, were also studied. The cleaning effect of the treatments was assessed immediately after the treatment and after one and two weeks by color spectrophotometry, a reliable tool to evaluate the presence and vitality of the phototrophs and the cleaning effectiveness in granite. C. nepeta and its active component Pulegone proved to be the most effective and yielded similar results, comparable to those of uncolonized granite, and better than those obtained with Preventol RI-80 (R) applied with brush (most common way), especially at the end of the experiment. These
promising first results support the suitable use of the phytochemical compounds used on phototrophs field where there are still few published studies and encourage further investigation toward the evaluation of their exhibited biocidal activity.

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## Phycoremediation potential of microalgae species for ethidium bromide removal from aqueous media

**Authors:** de Almeida HC, Salomao ALD, Lambert J, Teixeira LCRS, Marques M

INTERNATIONAL JOURNAL OF PHYTOREMEDIATION
Early Access, 2020, DOI: 10.1080/15226514.2020.1743968

**Abstract:** Ethidium Bromide (EtBr) is an organic compound used in molecular biology investigations. EtBr ability of intercalating in the DNA molecule makes it a toxic substance. The objective was to evaluate the phycoremediation potentials of *Chlorella vulgaris*, *Desmodesmus subspicatus* and *Raphidocelis subcapitata* tested separately and in a mixture (Mix) for EtBr removal from the aqueous medium. Experiments were conducted using an initial algae biomass of 10(6) cell/mL, exposed to 500 µg/L of EtBr. The removal efficiency (µg EtBr L-1) after 3 h in each treatment were: Mix (72.8 µg.L-1) *D. subspicatus* (48.4 µg.L-1) *R. subcapitata* (24.6 µg.L-1) *C. vulgaris* (19.9 µg.L-1). However, when EtBr mass reduction per microalgae density is considered (ng.algae-1), the efficiency ranking changes to: *D. subspicatus* (1.9 x 10(-5)ng.algae-1) *C. vulgaris* (1.4 x 10(-5)ng.algae-1) Mix (9.8 x 10(-6)ng.algae-1) *R. subcapitata* (2.8 x 10(-6)ng.algae-1). The results suggest that initial algal population density is a determinant factor for efficient EtBr removal by microalgae species in short term treatments. In order to obtain 100% of EtBr removal, it should be necessary 10(10), 10(10) and 10(11) algae.mL-1 of *C. vulgaris*, *D. subspicatus* and *R. subcapitata*, respectively. The results strongly suggest phycoremediation can be explored as an alternative method for EtBr removal.

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## Role of bacterial cell surface sulfhydryl sites in cadmium detoxification by *Pseudomonas putida*

**Authors:** Yu Q, Mishra B, Fein JB

**Source:** JOURNAL OF HAZARDOUS MATERIALS
391:122209, 2020, DOI: 10.1016/j.jhazmat.2020.122209

**Abstract:** Understanding bacterial metal detoxification systems is crucial for determining the environmental impacts of metal pollution and for developing advanced bioremediation and water disinfection strategies. Here, we explore the role of cell surface sulfhydryl sites in bacterial detoxification of Cd, using *Pseudomonas putida* with surface sulfhydryl sites mostly on its EPS molecules as a model organism. Our results show that 5 and 20 ppm Cd in LB growth medium affects the lag phase of *P. putida*, but not the overall extent of cell growth at stationary phase, indicating that *P. putida* can detoxify Cd at these concentrations. EXAFS analysis of Cd bound to biomass from the different growth stages indicates that Cd binds to both sulfhydryl and non-sulfhydryl sites, but that the importance of Cd-sulfhydryl binding increases from early exponential to stationary phase. Cell growth is positively correlated to the measured sulfhydryl concentration on different biomass samples, but is independent of the measured non-sulfhydryl binding site concentration on the cell surfaces. Taken together, our results demonstrate that the sulfhydryl binding sites on EPS molecules can play an important role in binding and detoxifying toxic metals, significantly decreasing the bioavailability of the metal by sequestering it away from the bacterial cells.

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## The Response of Microalgae *Chlorella* sp. to Free and Immobilized ZrO2 and
# Mg(OH)(2) Nanoparticles: Perspective from the Growth Characteristics

**Authors:** Fu MW, Liang J, Wang SF, Geng C, Zhang WY, Wu T

**Source:** ENVIRONMENTAL ENGINEERING SCIENCE Early Access, 2020, DOI: 10.1089/ees.2019.0367

**Abstract:** The biological response of *Chlorella* to nanometal oxides is the basis for expanding the engineering application of *Chlorella* and inorganic metal oxide nanoadsorbents in the treatment of nitrogen and phosphorus wastewater. The objective of this study was to ascertain the response of *Chlorella* to nano-ZrO2 and nano-Mg(OH)(2) either free or immobilized to anion exchange resin D301. Our results show that immobilization of ZrO2 and Mg(OH)(2) to D301 was significantly less harmful (p &\#60; 0.05) to *Chlorella* than free nano-ZrO2 and nano-Mg(OH)(2). *Chlorella* has greater tolerance and positive biological response to fixed nanometal oxides, especially to D301-ZrO2 (nano-ZrO2 immobilized on D301), which can significantly stimulate the growth of *Chlorella*. Scanning electron microscopy observations indicated that most of algal cells treated with free nano-Mg(OH)(2) and nano-ZrO2 were entrapped in the aggregates of nanoparticles and were both deformed and atrophied in appearance. In contrast, D301-Mg [nano-Mg(OH)(2) immobilized on D301] immobilized beads demonstrated relatively few malformed algal cells on the surface, and D301-Zr showed no indications of deformed or atrophied cells either within or on the immobilized beads. Therefore, immobilization appears to have obvious effect on reducing the toxicity of powder nanoparticle and carrier, and the immobilization of ZrO2 and Mg(OH)(2) on D301 might provide a novel application to *Chlorella* wastewater treatment to improve algae wastewater treatment efficiency, as well as these sorts of immobilized nanoadsorbent might be regenerated using Chlorella.

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## Integrated assessment of west coast of South Korea by use of benthic bacterial community

## structure as determined by eDNA, concentrations of contaminants, and in vitro bioassays

**Authors:** Lee AH, Lee J, Hong S, Kwon BO, Xie YW, Giesy JP, Zhang XW, Khim JS

**Source:** ENVIRONMENT INTERNATIONAL 137:UNSP 105569, 2020, DOI: 10.1016/j.envint.2020.105569

**Abstract:** During the past few decades, contamination of sediments by persistent toxic substances (PTSs) has been observed in estuarine and coastal areas on the west coast of South Korea. The contaminants are suspected to cause toxicities in aquatic biota, but little is known about their ecological effects, particularly on benthic microbial communities. In this study, an eDNA-based assessment was applied along with classic assessments of exposure, such as chemistry and in vitro bioassays, to evaluate condition of benthic bacterial communities subjected to PTSs. Two strategies were adopted for the study. One was to conduct a comprehensive assessment in space (by comparing seawater and freshwater sites at five coastal regions) and in time (by following change over a 5-y period). Although we found that bacterial composition varied among and within years, some phyla, such as Proteobacteria (28.7%), Actinobacteria (13.1%), Firmicutes (12.7%), and Chloroflexi (12.5%) were consistently dominated across the study regions. Certain bacterial groups, such as Firmicutes and Verrucomicrobia have been linked to contamination at some sites in the study area and at specific points in time. Bacterial communities were not significantly correlated with salinity or AhR- and ER-mediated potencies, whereas concentrations of PAHs, APs, and certain metals (Cd and Hg) exhibited significant associations to the structure of bacterial communities at the phylum level. In fact, the relative abundance of microbes in the phylum Planctomycetes was significantly and negatively correlated with concentrations of PAHs and metals. Thus, the relative abundance of Planctomycetes could be used as an indicator of sedimentary contamination by PAHs and/or metals. Based on our correlation analyses, Cd and ER-mediated potencies were associated more with bacterial abundances at the class taxonomic level than were other PTSs and metals. Overall, the eDNA-based assessment was useful by augmenting more traditional measures of exposure and responses in a sediment triad
approach and has potential as a more rapid
screening tool.

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Limited effects of pesticides
on stream
macroinvertebrates, biofilm
nematodes, and algae in
intensive agricultural
landscapes in Sweden

Authors: Bighiu MA, Hoss S, Traunspurger W, Kahlert M, Goedkoop W

Source: WATER RESEARCH 174:115640, 2020, DOI: 10.1016/j.watres.2020.115640

**Abstract:** Pesticides are frequently detected in surface waters, sometimes at levels exceeding ecotoxicological guidelines. We screened for almost 100 pesticides in 32 streams from intense agricultural areas in Southern Sweden, in concert with water chemistry parameters. In addition, we investigated the communities of benthic macroinvertebrates, biofilm nematodes and algae and calculated multiple bioassessment metrics. The number of pesticides found in each stream ranged between 2 and 52, but the sum of Toxic Units (Sigma TU) for the mixtures was generally low, and exceeded the European Uniform Principles only in a single sample for algae and in 2% of the samples for Daphnia. Only nematode communities were significantly correlated with the Sigma TU, potentially due to their higher pesticide exposure in biofilms. Diatom metrics showed that most streams were impacted by eutrophication and macroinvertebrate metrics showed good status in most streams, whereas the SPEAR(pesticides) (SPEcies At Risk) index, specifically designed to indicate pesticide effects, showed that about half of the samples were at risk. Interestingly, SPEAR(pesticides) was not correlated to Sigma TUDaphnia and this discrepancy suggests that redefining the boundaries for quality classes might be necessary for this index. Moreover, SPEAR(pesticides) was positively correlated with the commonly used macroinvertebrate index ASPT, although disparate results were found for several streams. We argue that this questions the scaling of both metrics and the specificity of their responses. We discuss that the overall good/moderate status of the streams, despite the intense agriculture in the

catchments, can be due to the fact that i) a
sampling strategy with repeated grab samples did
not capture peak pesticide concentrations, thus
underestimating acute exposure, ii) pesticide run-
off indeed was low, due to measures such as
buffer strips, and iii) the nutrient-rich conditions
and high sediment loads counteracted pesticide
toxicity. We conclude that agricultural land use
was the overriding stressor in the investigated
streams, including strong effects of nutrients, less
apparent effects of pesticides and likely impact of
hydromorphological alterations (not specifically
addressed in this study).

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Assessing the effects of metal
mining effluents on
freshwater ecosystems using
biofilm as an ecological
indicator: Comparison
between nanofiltration and
nanofiltration with
electrocoagulation treatment
technologies

Authors: Vendrell-Puigmitja L, Abril M, Proia L, Angona CE, Ricart M, Oatley-Radcliffe DL, Williams PM, Zanain M, Llenas L

Source: ECOLOGICAL INDICATORS 113:106213, 2020, DOI: 10.1016/j.ecolind.2020.106213

**Abstract:** Abandoned mines cause serious environmental damage to their surroundings with considerable impacts on freshwater ecosystems. These impacts occur mainly due to the uncontrolled discharge of polluted effluents, which may contain high concentrations of heavy metals. Currently, no real solution exists for this important environmental problem, leaving a legacy of global pollution. This study aimed to assess the impact of a metal mining effluent from an abandoned mine on freshwater ecosystems, using aquatic biofilms as an ecological indicator. At the same time, the efficiency of different innovative treatment technologies in reducing the ecological impacts caused by mining effluents was evaluated, consisting of nanofiltration and nanofiltration combined with electrocoagulation. To do that, aquatic biofilms obtained from a pristine stream, were exposed, under microcosms
conditions, to a metal mining effluent, untreated or treated by the innovative treatment technologies and responses were compared with unexposed biofilm which served as control. The structural and functional responses of the biofilm were measured with throughout time. Biofilms that were exposed to the untreated mining effluent showed significant differences respect to the rest of treatments and the control, particularly exhibiting inhibitory effects on photosynthetic efficiency just after 24 h of exposure and a progressive shift of the photosynthetic community composition throughout the exposure period. The treatment technologies significantly reduced the ecological impact caused by the metal mining effluent. However, metal bioaccumulation in biofilm revealed a potential long-term impact. These observations evidenced the biofilm as a useful ecological indicator to assess the ecological impact caused by metal mining effluents on freshwaters and the efficiency of different treatment technologies to reduce it.

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# Metatranscriptomic Insights Into the Response of River Biofilm Communities to Ionic and Nano-Zinc Oxide Exposures

**Authors:** Bergsveinson J, Roy J, Maynard C, Sanschagrin S, Freeman CN, Swerhone GDW, Dynes JJ, Tremblay J, Greer CW, Korber DR, Lawrence JR

**Source:** FRONTIERS IN MICROBIOLOGY 11:267, 2020, DOI: 10.3389/fmicb.2020.00267

**Abstract:** Manufactured Zn oxide nanoparticle (ZnO-NP) are extensively used world-wide in personal care and industrial products and are important contaminants of aquatic environments. To understand the overall impact of ZnO-NP contamination on aquatic ecosystems, investigation of their toxicity on aquatic biofilms is of particular consequence, given biofilms are known sinks for NP contaminants. In order to assess alterations in the functional activity of river microbial biofilm communities as a result of environmentally-relevant ZnO-NP exposure, biofilms were exposed to ionic zinc salt or ZnOPs that were uncoated (hydrophilic), coated with

silane (hydrophobic) or stearic acid (lipophilic), at a total concentration of 188 µg l-1 Zn. ICP-MS analyses of biofilms indicated ZnO-NP concentrated in the biofilms, with hydrophilic, hydrophobic, and lipophilic treatments reaching 0.310, 0.250, and 0.220 µg Zn cm-2 of biofilm, respectively, while scanning transmission X-ray microspectroscopy (STXM) analyses of biofilms confirmed that Zn was extensively- and differentially-sorbed to biofilm material. Microbial community composition, based on taxonomic affiliation of mRNA sequences and enumeration of protozoa and micrometazoa, was not affected by these treatments, and the total transcriptional response of biofilms to all experimental exposures was not indicative of a global toxic-response, as cellular processes involved in general cell maintenance and housekeeping were abundantly transcribed. Transcripts related to major biological processes, including photosynthesis, energy metabolism, nitrogen metabolism, lipid metabolism, membrane transport, antibiotic resistance and xenobiotic degradation, were differentially expressed in Zn-exposures relative to controls. Notably, transcripts involved in nitrogen fixation and photosynthesis were decreased in abundance in response to Zn-exposure, while transcripts related to lipid degradation and motility-chemotaxis were increased, suggesting a potential role of Zn in biofilm dissolution. ZnO-NP and ionic Zn exposures elicited generally overlapping transcriptional responses, however hydrophilic and hydrophobic ZnO-NPs induced a more distinct effect than that of lipophilic ZnO-NPs, which had an effect similar to that of low ionic Zn exposure. While the physical coating of ZnO-NP may not induce specific toxicity observable at a community level, alteration of ecologically important processes of photosynthesis and nitrogen cycling are an important potential consequence of exposure to ionic Zn and Zn oxides.

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# Influence of polystyrene microplastics on the growth, photosynthetic efficiency and aggregation of freshwater
## microalgae *Chlamydomonas reinhardtii*

**Authors:** Li SX, Wang PP, Zhang C, Zhou XJ, Yin ZH, Hu TY, Hu D, Liu CC, Zhu LD

**Source:** SCIENCE OF THE TOTAL ENVIRONMENT 714:136767, 2020, DOI: 10.1016/j.scitotenv.2020.136767

**Abstract:** Microplastics are ubiquitous in aquatic ecosystems worldwide, but knowledge on their impacts on phytoplankton, especially freshwater microalgae, is still limited. To investigate this issue, miaoalgae *Chlamydomonas reinhardtii* was exposed to polystyrene (PS) microplastics with 4 concentration gradients (5, 25, 50 and 100 mg/L), and the growth, chlorophyll a fluorescence, photosynthetic activities (Fv/Fm), the contents of malondialdehydes (MDA), soluble proteins, extracellular polymeric substances (EPS) and settlement rate were accordingly measured. Results showed that the density of microalgae decreased as the increase of PS microplastics concentrations, and the highest inhibitory rate (IR) was 45.8% on the 7th day under the concentration of 100 mg/L The high concentration (100 mg/L) of microplastics evidently inhibited the content of EPS released by microalgae into the solution. PS under all dosages tested could reduce both the chlorophyll a fluorescence yields and photosynthetic activities. The scanning electron microscope (SEM) images demonstrated that microplastic beads were wrapped on the surface of microalgae and damaged their membranes, which could suggest the reduction of photosynthetic activities and the increase of soluble proteins and MDA content. The results also showed that PS microplastics could inhibit the settlement of microalgae at the later stage, which also indicated the recovery of miaoalgae from the toxic environment. Our findings will contribute to understanding the effects of microplastics on freshwater microalgae, as well as evaluating the possible influences of microplastics on aquatic ecosystems.

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> Urbanization drives riverine bacterial antibiotic resistome more than taxonomic

## community at watershed scale

**Authors:** Peng F, Guo YY, Isabwe A, Chen HH, Wang YM, Zhang YP, Zhu ZX, Yang J

**Source:** ENVIRONMENT INTERNATIONAL 137:UNSP 105524, 2020, DOI: 10.1016/j.envint.2020.105524

**Abstract:** Although the occurrence and distribution of antibiotic resistance genes (ARGs) in various aquatic ecosystems are well explored, understanding of the ecological processes and mechanisms governing the composition and dynamics of bacterial ARGs still remains limited across space and time. Here, we used high-throughput approaches to detect spatial patterns of bacterial ARGs and operational taxonomic units (OTUs) in an urbanizing subtropical watershed, Xiamen, southeast China over a five-year period. At watershed scale, the OTU profiles were undergoing a directional change, but the ARG profiles showed a high stability or stochastic change over time. Compared with the upstream and midstream, the richness, absolute abundance, normalized abundance and diversity of ARGs were significantly higher in the downstream waters. Our results revealed a clear rural-urban disparity in ARG and OTU profiles which were mainly governed by deterministic and stochastic assembly processes, respectively. With the increase of urban building area along the river, the ecological processes of ARG profiles shifted from stochastic to deterministic. In downstream waters, the bacterial ARG profiles were much more stable than bacterial OTUs. Further, our results indicated that both human-dominated environment (e.g., land use) and mobile genetic elements (MGEs) played an important role in shaping the ARG profiles and dynamics. Overall, this was a response to spatially extensive human-landscape interactions that included urban development in the river downstream region, which were common across subtropical coastal cities of China and can alter the ARG profile dynamics along rural-urban gradient. Therefore, watershed management actions aiming at reducing threats posed by ARGs in urbanizing watershed should first consider the surrounding urbanization level and the mode and intensity of human activity. Our findings also imply that due to the decoupling of bacterial function and taxonomy, both aspects should be studied separately.

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## Characterization of antibiotic resistance genes and bacterial community in selected municipal and industrial sewage treatment plants beside Poyang Lake

**Authors:** Ding HJ, Qiao M, Zhong JY, Zhu YG, Guo CJ, Zhang QQ, Yang P, Han L, Zhang WH, Wu YX, Liu JT, Zhang LT, Sun JH

**Source:** WATER RESEARCH 174:115603, 2020, DOI: 10.1016/j.watres.2020.115603

**Abstract:** Sewage treatment plants (STPs) are significant reservoirs of antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB). Municipal STPs (MSTPs) and industrial STPs ([STPs] are the two most important STP types in cities. In this study, the ARGs, mobile genetic elements (MGEs), and bacterial communities of selected STPs, including two MSTPs and one ISTP, in the vicinity of Poyang Lake were comprehensively investigated through high-throughput qPCR and high-throughput Illumina sequencing. The results showed that the profiles of ARGs, MGEs and bacteria differed between the ISTP and the two MSTPs, most likely due to differences in influent water quality, such as the Pb that characterized in the ISTP's influent. The longer hydraulic retention times (HRTs) of the two MSTPs than of the ISTP may also have accounted for the different profiles. Thus, a prolonged HRT in the CASS process seems to allow a more extensive removal of ARGs and bacteria in ISTPs with similar treatment process. By providing comprehensive insights into the characteristics of ARGs, MGEs and the bacterial communities of the selected MSTPs and ISTP, our study provides a scientific basis for controlling the propagation and diffusion of ARGs and ARB in different types of STPs.

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## The roles of silicon in combating cadmium challenge in the Marine

### diatom tricornutum

### Phaeodactylum tricornutum

**Authors:** Ma J, Zhou BB, Tan QG, Zhang L, Pan K

**Source:** JOURNAL OF HAZARDOUS MATERIALS 389:121903, 2020, DOI: 10.1016/j.jhazmat.2019.121903

**Abstract:** Marine phytoplankton possess a sophisticated homeostatic network to counteract metal toxicity. Changes in environmental conditions such as ambient nutrient concentrations can significantly impact their intrinsic metal sensitivity. In this study, we evaluated the role of silicon (Si) in counteracting cadmium (Cd) toxicity in the marine diatom *Phaeodactylum tricornutum*. We first demonstrated that Si enrichment dramatically enhanced Cd tolerance and changed the Cd accumulation in the diatom. Our modeling suggested that Si-enriched cells adsorbed more Cd but had a higher Cd elimination rate than the Si-starved cells. Examinations by atomic force microscopy and X-ray photoelectron spectroscopy revealed that the Si-enriched cells had better silification and more SiO₂ in the cell walls, which markedly lowered the surface potential of the diatom cells and allowed them to attract more Cd. Although the Si-enriched cells tended to have a high Cd burden when facing Cd stress, they suppressed the increase of intracellular Cd by both down-regulating the influx transporter ZIP and up-regulating the efflux transporter ATPase5-1B. Our study shows the significant roles Si plays in maintaining metal homeostasis and combating Cd challenge in marine diatoms.

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## In vivo toxicities of nine engineered nano metal oxides to the marine diatom *Skeletonema costatum* and rotifer *Brachionus koreanus*

**Authors:** Wong SWY, Zhou GJ, Kwok KWH, Djurisic AB, Han J, Lee JS, Leung KMY

**Source:** MARINE POLLUTION 153:110973, 2020, DOI: 10.1016/j.marpolbul.2020.110973

**Abstract:** This study compared in vivo acute toxicities of nine engineered nano metal oxides to
the marine diatom *Skeletonema costatum* and rotifer *Brachionus koreanus*. The sequence of their toxicities to *S. costatum*, based on growth inhibition, was: nano zinc oxide (nZnO) nTiO(2) (rutile) nMgO Annealed nMgO nTiO(2) (anatase) gamma-nAl(2)O(3) nIn(2)O(3) alpha-nAl(2)O(3) nSnO(2). Similarly, nZnO was also the most toxic to *B. koreanus*, but the other nano metal oxides were non-lethal. nMgO and nZnO were confirmed to trigger reactive oxygen species (ROS) mediated toxicity to the two marine organisms, while nTiO(2) (both anatase and rutile forms) likely induced oxidative stress as shown by their acellular ROS production. nZnO may also cause damage in the endocrine system of *B. koreanus*, as indicated by the increased transcription of retinoid X receptor. Annealed nMgO reduces its toxicity via removal of O-2 and impurities from its surface.

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## Changes in sediment microbial diversity following chronic copper-exposure induce community copper-tolerance without increasing sensitivity to arsenic

**Authors:** Ahmed AM, Tardy V, Bonnineau C, Billard P, Pesce S, Lyautey E

**Source:** JOURNAL OF HAZARDOUS MATERIALS
391:122197, 2020, DOI: 10.1016/j.jhazmat.2020.122197

**Abstract:** Sediment microbial communities were exposed for 21 days to an environmental concentration of copper to assess Cu-induced composition changes and resulting effects on microbial sensitivity to acute Cu and As toxicity. Chronic Cu exposure reduced the diversity of the bacterial and archaeal communities from Day 0 to Day 21. The pollution-induced community tolerance concept (PICT) predicts that loss of the most sensitive taxa and gain of more tolerant ones should increase the capacity of Cu-exposed communities to tolerate acute Cu toxicity. Although diversity loss and functional costs of adaptation could have increased their sensitivity to subsequent toxic stress, no increased sensitivity to As was observed. PICT responses varied according to heterotrophic activity, selected as the functional endpoint for toxicity

testing, with different results for Cu and As. This suggests that induced tolerance to Cu and As was supported by different species with different metabolic capacities. Ecological risk assessment of contaminants would gain accuracy from further research on the relative contribution of tolerance acquisition and co-tolerance processes on the functional response of microbial communities.

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## Microbial Degradation of Plastic in Aqueous Solutions Demonstrated by CO2 Evolution and Quantification

**Authors:** Rose RS, Richardson KH, Latvanen EJ, Hanson CA, Resmini M, Sanders IA

**Source:** INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES 21(4):1176, 2020, DOI: 10.3390/ijms21041176

**Abstract:** The environmental accumulation of plastics worldwide is a consequence of the durability of the material. Alternative polymers, marketed as biodegradable, present a potential solution to mitigate their ecological damage. However, understanding of biodegradability has been hindered by a lack of reproducible testing methods. We developed a novel method to evaluate the biodegradability of plastic samples based on the monitoring of bacterial respiration in aqueous media via the quantification of CO2 produced, where the only carbon source available is from the polymer. *Rhodococcus rhodochrous* and *Alcanivorax borkumensis* were used as model organisms for soil and marine systems, respectively. Our results demonstrate that this approach is reproducible and can be used with a variety of plastics, allowing comparison of the relative biodegradability of the different materials. In the case of low-density polyethylene, the study demonstrated a clear correlation between the molecular weight of the sample and CO2 released, taken as a measure of biodegradability.

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## Toxicological effects of ciprofloxacin and chlorhexidine on growth and
## chlorophyll a synthesis of freshwater cyanobacteria

**Authors:** Azevedo FCR, Vaz ICD, Barbosa FAR, Magalhaes SMS

**Source:** BRAZILIAN JOURNAL OF PHARMACEUTICAL SCIENCES 55:e17661, 2019, DOI: 10.1590/s2175-97902019000217661

**Abstract:** Cyanobacteria are phytoplanktonic microorganisms that are susceptible to the deleterious effects of pharmaceutical residues in the aquatic environment, which poses a challenge to the environment exposed to diverse pharmaceutical products and their potential effects. The objective of this study was to evaluate the effects of the antibiotic substances ciprofloxacin and chlorhexidine in pharmaceutical preparations on the growth and production of chlorophyll of two cyanobacterial strains, *Microcystis aeruginosa* and *Microcystis panniformis*, isolated from a lake in a Brazilian environmental protection area. The EC50 and EC10 of chlorhexidine for *M. aeruginosa* were 206.4 µg/L and 108.5 µg/L, respectively, and for *M. panniformis* were 171.4 µg/L and 116.6 µg/L, respectively. The EC50 and EC10 of ciprofloxacin for *M. aeruginosa* were 17.24 µg/L and 3.21 µg/L, respectively, and for *M. panniformis* were 13.56 µg/L and 1.50 µg/L, respectively. The toxicity of the antibiotic ciprofloxacin (drug) and chlorhexidine (standard solution) to the *Microcystis* species was demonstrated, and these species were both very sensitive to ciprofloxacin. Our results suggest that the strains of *M. aeruginosa* and *M. panniformis* may be affected by exposure to residues of ciprofloxacin (1.5 µg/L), which may represent a risk to the survival of aquatic species.

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## Biotransformation of Phthalate Plasticizers and Bisphenol A by Marine-Derived, Freshwater, and Terrestrial Fungi

**Authors:** Carstens L, Cowan AR, Seiwert B, Schlosser D

**Source:** FRONTIERS IN MICROBIOLOGY 11:317, 2020, DOI: 10.3389/fmicb.2020.00317

**Abstract:** Phthalate esters (PEs, Phthalates) are environmentally ubiquitous as a result of their extensive use as plasticizers and additives in diverse consumer products. Considerable concern relates to their reported xenoestrogenicity and consequently, microbial-based attenuation of environmental PE concentrations is of interest to combat harmful downstream effects. Fungal PE catabolism has received less attention than that by bacteria, and particularly fungi dwelling within aquatic environments remain largely overlooked in this respect. We have compared the biocatalytic and biosorptive removal rates of di-n-butyl phthalate (DBP) and diethyl phthalate (DEP), chosen to represent two environmentally prominent PEs of differing structure and hydrophobicity, by marine-, freshwater-, and terrestrial-derived fungal strains. Bisphenol A, both an extensively used plastic additive and prominent environmental xenoestrogen, was included as a reference compound due to its well-documented fungal degradation. Partial pathways of DBP metabolization by the ecophysiologically diverse asco- and basidiomycete strains tested were proposed with the help of UPLC-QTOF-MS analysis. Species specific biochemical reaction steps contributing to DBP metabolism were also observed. The involved reactions include initial cytochrome P450-dependent monohydroxylations of DBP with subsequent further oxidation of related metabolites, de-esterification via either hydrolytic cleavage or cytochrome P450-dependent oxidative O-dealkylation, transesterification, and demethylation steps - finally yielding phthalic acid as a central intermediate in all pathways. Due to the involvement of ecophysiologically and phylogenetically diverse filamentous and yeast-like fungi native to marine, freshwater, and terrestrial habitats the results of this study outline an environmentally ubiquitous pathway for the biocatalytic breakdown of plastic additives. Beyond previous research into fungal PE metabolism which emphasizes hydrolytic de-esterification as the primary catabolic step, a prominent role of cytochrome P450 monooxygenase-catalyzed reactions is established.

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## Response of Algae to Heavy Metal Removing with Particular Reference to pH
**Authors:** Aladdin LM, Aziz F

**Source:** POLISH JOURNAL OF ENVIRONMENTAL STUDIES 29(3):2041-2053, 2020, DOI: 10.15244/pjoes/110446

**Abstract:** The accumulation capacity of heavy metals by algae as affected by the pH of fresh water is the main objective of this work, which is the first unitary study in Akre-Dhouk Province of Iraq's Kurdistan region. The water samples of 10 selected sites in the months of August and November 2016 were analyzed using atomic absorption spectrometry in order to determine the bioaccumulation factor for taxa *Scytonema subcynatum*, *Nostoc muscarum*, *Batracospermum boryanum*, *Batracospermum atrum*, *Batracospermum moniliform*, *Spirogyra subsalsa*, *Oedogonium tumidulum*, and *Chara bruunii*. In water, we recorded the values of heavy metals content at permissible levels. For Chlorophyta and Cyanophytathe accumulation value positively correlated with pH, while in Rhodophyta it was negative. Consequently, the highest concentrations were registered by *Oedogonium tumidulum* for Ti (1019.361 µg.l-1), Cr (65.678 µg.l-1), Fe (2.380 µg.l-1), Co (7.846 µg.l-1), Ni (205.527 µg.l-1), As (12.591 µg.l-1), *Batracospermum boryanum* for Cu (196.257 µg.l-1), *Batracosoermu atrum* for Hg (0.069 µg.l-1), Pb (134.510 µg.l-1), *Batracospermum moniliform* for Zn (334.508 µg.l-1), Se (0.773 µg.l-1), *Spirogyra subsalsa*, for Mn (425.292 µg.l-1) and *Scytonema subcynatum* for Cd (0.075 µg.l-1).

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## Rapid Physicochemical Changes in Microplastic Induced by Biofilm Formation

**Authors:** McGivney E, Cederholm L, Barth A, Hakkarainen M, Hamacher-Barth E, Ogonowski M, Gorokhova E

**Source:** FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY 8: 205, 2020, DOI: 10.3389/fbioe.2020.00205

**Abstract:** Risk assessment of microplastic (MP) pollution requires understanding biodegradation processes and related changes in polymer properties. In the environment, there are two-way interactions between the MP properties and biofilm communities: (i) microorganisms may prefer some surfaces, and (ii) MP surface properties change during the colonization and

weathering. In a 2-week experiment, we studied these interactions using three model plastic beads (polyethylene [PE], polypropylene [PP], and polystyrene [PS]) exposed to ambient bacterioplankton assemblage from the Baltic Sea; the control beads were exposed to bacteria-free water. For each polymer, the physicochemical properties (compression, crystallinity, surface chemistry, hydrophobicity, and surface topography) were compared before and after exposure under controlled laboratory conditions. Furthermore, we characterized the bacterial communities on the MP surfaces using 16S rRNA gene sequencing and correlated community diversity to the physicochemical properties of the MP. Significant changes in PE crystallinity, PP stiffness, and PS maximum compression were observed as a result of exposure to bacteria. Moreover, there were significant correlations between bacterial diversity and some physicochemical characteristics (crystallinity, stiffness, and surface roughness). These changes coincided with variation in the relative abundance of unique OTUs, mostly related to the PE samples having significantly higher contribution of *Sphingobium*, *Novosphingobium*, and uncultured Planctomycetaceae compared to the other test materials, whereas PP and PS samples had significantly higher abundance of *Sphingobacteriales* and *Alphaproteobacteria*, indicating possible involvement of these taxa in the initial biodegradation steps. Our findings demonstrate measurable signs of MP weathering under short-term exposure to environmentally relevant microbial communities at conditions resembling those in the water column. A systematic approach for the characterization of the biodegrading capacity in different systems will improve the risk assessment of plastic litter in aquatic environments.

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Interaction between glyphosate and dissolved phosphorus on bacterial and
## eukaryotic communities from river biofilms

**Authors:** Carles L, Artigas J

**Source:** SCIENCE OF THE TOTAL ENVIRONMENT
719:137463, 2020, DOI:
10.1016/j.scitotenv.2020.137463

**Abstract:** Since the capacity of river biofilms to degrade glyphosate has been proven to increase when the availability of dissolved phosphorus (P) in water decreases, the present study investigates the diversity responses of bacterial and eukaryotic microbial communities from biofilms in a search for glyphosate-degrader candidates. Glyphosate and P interactions were observed for eukaryotic communities, the highest community richness and diversity being preserved at low concentrations of glyphosate and P. This trend marked by glyphosate was also observed in the structure of eukaryotic communities. Therefore, phosphorus and glyphosate had a synergistic effect in decreasing the richness and diversity of eukaryotes species in biofilms. However, species richness and diversity in bacterial communities were not affected by glyphosate, though shifts in the structure of these communities were concomitant with the degradation of the herbicide. Bacterial communities capable of using glyphosate as P source were characterized by increases in the relative abundance of certain Bacteroidetes, Chloroflexi, Cyanobacteria, Planctomycetes and alpha-Proteobacteria members. Glyphosate-degrader candidates found in natural river biofilms can be further isolated for better understanding of glyphosate degradation pathways, and used as bioremediation strategies in heavily contaminated sites.

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## The response of Prorocentrum sigmoides and its associated culturable bacteria to metals and organic pollutants

**Authors:** D'Costa PM, Kunkolienkar RSS, Naik AG, Naik RK, Roy R

**Source:** JOURNAL OF BASIC MICROBIOLOGY
59(10):979-991, 2020, DOI:
10.1002/jobm.201900244

**Abstract:** This study investigates the effect of metals (cadmium, lead, mercury, and tellurium) and organic pollutants (benzene, diesel, lindane, and xylene) on a dinoflagellate-Prorocentrum sigmoides Bohm-and its associated culturable bacteria. Two bacterial cultures (*Bacillus subtilis* strain PD005 and *B. xiamensis* strain PD006) were isolated from *P. sigmoides* and characterized by scanning electron microscopy, 16S ribosomal RNA sequencing, biochemical analyses, and growth curve studies. This study points to a mutualistic relationship between *P. sigmoides* and its associated *Bacillus* isolates. *P. sigmoides* enhanced the growth of its associated *Bacillus* spp., through the secretion of extracellular exudates. In return, both *Bacillus* isolates contributed to the resistance of *P. sigmoides* to metals and organic pollutants. *P. sigmoides* and both *Bacillus* isolates exhibited concentration-dependent responses to metals and organic pollutants. An intriguing feature was the similar response of *P. sigmoides* and its associated *Bacillus* isolates to mercury and cadmium, indicating a co-selection of mercury and cadmium resistance. This provides support to the "dinoflagellate host-phycosphere bacteria" behaving as a single functional unit. However, the sensitivity profiles of *P. sigmoides* and its associated *Bacillus* isolates are different with respect to metals versus organic pollutants. These aspects need to be addressed in future studies to unravel the effect of metal and organic pollutants on dinoflagellates, an important component of the phytoplankton community, and to discern the influence of associated "phycosphere" bacteria on the response of dinoflagellates to pollutants.

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## Effects of microplastic biofilms on nutrient cycling in simulated freshwater systems

**Authors:** Chen XC, Chen XF, Zhao YH, Zhou H, Xiong X, Wu CX

**Source:** SCIENCE OF THE TOTAL ENVIRONMENT
719:137276, 2020, DOI:
10.1016/j.scitotenv.2020.137276

**Abstract:** Microplastic surfaces could be colonized by microorganisms and form biofilms in aquatic ecosystem, which can participate in the nitrogen (N) and phosphorus (P) cycles. In this work, polypropylene squares were deployed in a pond for 30 clays for microplastic biofilms colonization
and then were transported to indoor microcosms at an environmental relevant level to study their effects on N and P cycling. Results showed that microplastic biofilms could accelerate ammonia and nitrite oxidation as well as denitrification. Presence of microplastic biofilms accumulated P temporarily and increased alkaline phosphatase activities (APA) in the system. Later in the experiment, disintegration of matured biofilms released N and P into the water. Mass balance calculation suggested possible N input caused by biological nitrogen fixation. Our results demonstrated that microplastics associated biofilms have the ability to alter the N and P cycling processes in aquatic system. However, additional works are required to further quantify the extent of such impact.

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## Diatom mediated heavy metal remediation: A review

Authors: Marella TK, Saxena A, Tiwari A

Source: BIORESOURCE TECHNOLOGY 305:123068, 2020, DOI: 10.1016/j.biortech.2020.123068

**Abstract:** Exposure to heavy metals is a major threat to aquatic bodies and is a global concern to our four main spheres of the earth viz. atmosphere, biosphere, hydrosphere, and lithosphere. The biosorption of pollutants using naturally inspired sources like microalgae has considerable advantages. Diatoms are the most dominant and diverse group of phytoplankton which accounts for 45% oceanic primary productivity. (...) The diatoms play a significant role in degradation, speciation, and detoxification of chemical wastes and hazardous metals from polluted sites. Herein, an overview is presented about the ability of diatom algae to phycoremediate heavy metals by passive adsorption and active assimilation from their aqueous environments with an emphasis on extracellular and intracellular mechanisms involved in contaminant uptake through the frustules for preventing heavy metal toxicity.

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## Characterization of indigenous bacteria from radon-rich groundwater and

## their tolerance to physicochemical stress

Authors: Nayak T, De D, Barman C, Karmakar P, Deb A, Dhal PK

Source: INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY 17(3):1627-1636, 2020, DOI: 10.1007/s13762-019-02445-w

**Abstract:** Radiation exposure and heavy metal (HM) exposure are serious health hazards causing DNA mutation, oxidative damage and may also be responsible for various life-threatening human diseases, while bacteria can withstand such toxicity easily. This study attempted to identify inhabitant bacterial isolates from radon-contaminated groundwater of Tantloi, India, and effort has also been made to characterize their response against radiation, oxidative stress as well as heavy metal tolerance and removal. Total sixteen (16) bacterial isolates were identified as *Bacillus* spp., *Stenotrophomonas* spp., *Brevibacillus* sp., *Chryseobacterium* sp., *Escherichia* sp. and *Microbacterium* sp., which showed less number of distinct carbohydrates utilization potential but high salinity tolerance properties. In addition, Gram-positive Bacillus spp. can tolerate 1 kGy of gamma radiation, 10 mM H2O2, 7 days of desiccation and different heavy metals (Cu, Pb, Cr, Zn and As). Four Bacillus spp. and *Microbacterium* sp., which showed total maximum tolerable concentration (MTC) 8 out of 5 heavy metals, were considered for their HM removal property analysis. Five multimetal resistance strains had strong removal capacity of Pb and Zn (89-94%) followed by Cr (49-56%) and Cu/As (0.4-22%). This investigation may provide baseline information of radon-contaminated groundwater microbiology, thus could be used to formulate an appropriate strategy for radon and radionuclides remediation.

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## Highlighting of the antialgal activity of organic extracts of Moroccan macrophytes: potential use in cyanobacteria blooms control

Authors: Tazart Z, Douma M, Caldeira AT, Tebaa L, Mouhri K, Loudiki M
**Source:** ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH, Early Access, 2020, DOI: 10.1007/s11356-020-08440-w

**Abstract:** Many studies have demonstrated the effectiveness of algicidal compounds produced by macrophytes against microalgae. The aim of this study was to assess the algicidal activity of seven Moroccan macrophyte ethyl acetate extracts (MEA) to control harmful algal blooms (HABs). The response and sensitivity of prokaryotic toxic cyanobacteria (*Microcystis aeruginosa*) and eukaryotic microalgae (*Chlorella* sp.) were highlighted. The algicidal effect of MEA extracts against the two microalgae was assessed using both the paper disc diffusion and microdilution methods. This last was used in order to evaluate the minimum inhibitory concentrations (MIC) and minimum algicidal concentrations (MAC). Results showed that the growth of both microalgae was significantly inhibited by all MEA extracts. *Myriophyllum spicatum* organic extract shows the highest growth inhibition activity against *M. aeruginosa* (35.33 ± 1.53) and *Chlorella* sp. (30.33 ± 1.15 mm). This stronger inhibitory activity was confirmed by the low MIC (6.25, 12.5 mg/L) and MAC (6.25, 12.5 mg/L) values. Furthermore, results showed different sensitivity between the prokaryotic and eukaryotic microalgae into MEA extracts. Based on the MIC and MAC values, we can distinguish two groups of plants. The first one, including *M. spicatum*, *Ranunculus aquatilis*, and *Enteromorpha* sp., can be considered as a preferable anti-prokaryotic group with a stronger inhibitory activity on *M. aeruginosa* growth. The second group, constituted by *Potamogeton natans*, *Nasturtium officinale*, *Elodea* sp., and *Ceratophyllum* sp., has a preferable and stronger inhibitory effect against eukaryotic algae (*Chlorella* sp.). Overall the results reveal the potential algicidal activity of macrophytes and suggested that MEA extracts could play an important role in biocontrol of HABs.

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# Toxicity evaluation of iron oxide nanoparticles and accumulation by microalgae *Coelastrella terrestris*

Authors: Saxena P, Sangela V, Harish

**Source:** ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH Early Access, 2020, DOI: 10.1007/s11356-020-08441-9

**Abstract:** Uses of iron oxide nanoparticles have increased in the last decade. The increased application marked a concern regarding their fate and behavior in the environment. Especially towards the aquatic ecosystems, as the ultimate descend of these iron oxide nanoparticles are aquatic bodies. The greater surface area per mass compared with larger-sized materials of the same chemistry renders these nanoparticles biologically more active. (...) In the present study, comparative assessment of iron oxide nanoparticles and their bulk counterpart have been monitored using *Coelastrella terrestris* up to 40 days. Interestingly, study reveals the potential of *Coelastrella terrestris* as tool for the bioremediation of iron nanoparticles to combat nano-pollution. Adsorption/absorption kinetics measured after 25 days of treatments with iron oxide nanoparticle and its bulk counterpart revealed higher absorption levels in comparison to the adsorption with maximum accumulation factor (AF) of 2.984 at 50 mg L-1 in nano-form. Iron oxide absorption was found linearly related with concentration in both cases (y = 11.313x-12.165, R-2 = 0.8691 in nano; y = 6.35x-5.74, R-2 = 0.8128 in bulk). However, 50-mg L-1 nanoparticle concentration was perceived sub-lethal for the algae with 33.33% algal growth reduction under nano and 27.77% under bulk counterpart. Other biochemical parameters, i.e., SOD, CAT, MDA, and lipid quantification, were also quantified to correlate the state of metabolism of treated algal cells in comparison to the control and these exhibited reduction in algal growth due to oxidative stress. Morphological changes were monitored through SEM and TEM.

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# Pollution shapes the bacterial community of a river: a case study

Authors: Yadav N, Sharma S

**Source:** INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY 17(4):2003-2016, 2020, DOI: 10.1007/s13762-019-02474-5
**Abstract:** Bacteria are involved in many vital biogeochemical functions in aquatic ecosystems. Owing to their small size and high growth rates, they tend to be highly responsive to any changes in their environment. This potential to reflect any kind of environmental change makes them sensitive indicators towards the effect of pollutants in aquatic systems. The present study focused on investigation of change in the bacterial community structure of Hindon River in Ghaziabad in North India, in relation to the river's pollution levels. Both spatial and temporal variation in the resident as well as active bacterial community was determined using 16S rRNA gene and transcript as molecular markers through denaturing gradient gel electrophoresis. Sequence analysis of eluted bands showed that Bacteroidetes followed by gamma-proteobacteria, Actinobacteria, beta-proteobacteria, delta-proteobacteria, epsilon-proteobacteria and Nitrospirae, represented the dominant phyla. Moreover, the effect of pollutants on the bacterial diversity was more conspicuous at RNA level. In addition, when assessing the diversity of culturables, 8 bacterial strains, having minimum inhibitory concentrations in the range of 200-250 mg l-1 for Ni, 75-200 mg l-1 for Co and 75-200 mg l-1 for Cd, were isolated and characterized. The identified bacteria have the potential to be used as sensitive biomarkers for the development of bioremediation strategies and their monitoring.

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## pH affects the hormesis profiles of personal care product components on luminescence of the bacteria *Vibrio qinghaiensis* sp.-Q67

Authors: Xu YQ, Liu SS, Chen F, Wang ZJ

Source: SCIENCE OF THE TOTAL ENVIRONMENT
713:136656, 2020, DOI:
10.1016/j.scitotenv.2020.136656

**Abstract:** Hormesis describes a specific phenomenon in a biphasic concentration-response curve: low concentrations stimulate a response, while high concentrations suppress it. Hormesis could be influenced by several environmental factors, e.g. pH. In this study, the concentration-response/bioluminescence inhibition profiles (CRP5) of six components in personal care

products to Vibrio qinghaiensis sp.-Q67 were measured at five different pH levels. When the exposure lasted for 0.25 h, CRPs of the six components at various pH levels were S-shaped, except ascorbic add 2-glucoside (AA2G) at pH 10.5. When it lasted for 12 h, the CRPs were J-shaped, except AA2G at pH 6.5, 7.5, and 9.5. To rationally explain these changes in hormesis expressed by J-shaped CRP, four characteristic parameters, the minimum effect (E-min) and its corresponding concentration (ECmin), the median effective concentration (EC50), and the zero effect concentration point (ZEP, where the effect is 0 and the concentration is ZEP), were used to quantify the J-shaped CRP. The results indicated that these parameters vary with pH. Additionally, ZEP showed an excellent linear relationship with EC10 (R-2 = 0.9994) at all pH levels, indicating that EC(10) could replace the no-observed effective concentration (NOEC) in ecological risk assessment. Furthermore, to elucidate the possible mechanism of hormesis, the binding of the components to the luciferase receptors was analyzed using molecular docking technology. The results showed that the components displaying hormesis bind more easily to the alpha subunit of luciferase than to the beta subunit.

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## Multistressor negative effects on an experimental phytoplankton community. The case of glyphosate and one toxigenic cyanobacterium on Chlorophycean microalgae

Authors: Hernandez-Garcia CI, Martinez-Jeronimo F

Source: SCIENCE OF THE TOTAL ENVIRONMENT
717:137186,2020, DOI:
10.1016/j.scitotenv.2020.137186

**Abstract:** Aquatic ecosystems face serious pollution issues. Discharges of toxic substances and eutrophication may lead to changes in the phytoplankton community and foster cyanobacterial blooms. Glyphosate-based herbicides are chemical stressors of microalgae that may affect the structure of phytoplankton communities, and also stimulate the synthesis of cyanotoxins by cyanobacteria. The simultaneous presence of glyphosate and toxigenic
cyanobacteria increases the stress on microalgae, jointly affecting their growth and development. This study evaluated the combined effect of a toxigenic cyanobacterium and glyphosate in the development of an experimental microalgal community. We studied the effect of *Microcystis aeruginosa* on the population growth of the microalgae *Ankistrodesmus fakatus*, *Chlorella vulgaris*, *Pseudokirchneriella subcapitata*, and *Scenedesmus incrassatulus*. We also evaluated the combined effect of sub-inhibitory glyphosate (Faena (R)) concentrations on the content of macromolecules and the enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), as well as on the concentration of TBARS. These effects were evaluated through the integrated biomarker response (IBR). In individual experiments, microalgae showed lower growth rates versus *M. aeruginosa*. In the mixed bioassays, both *M. aeruginosa* and microalgae showed reduced growth. IC50 values for Faena (R) ranged from 1.022 to 2.702 mg L-1. In the microalgae cyanobacteria bioassays, the herbicide lowered the growth rates of microalgae but stimulated the proliferation of *M. aeruginosa*. The joint action of both stressors affected growth rate and population dynamics, macromolecule content, and led to increased CAT and GPx levels. Faena (R) influenced growth rate and caused oxidative stress. On the other hand, the herbicide stimulated the synthesis of cyanotoxins, which further affected microalgal development. The experimental community was not only affected by the herbicide, but the mixed culture with cyanobacteria magnified the effects chemical stress. These results illustrate the potential damage to phytoplankton expected in anthropically eutrophic water bodies that are also polluted by glyphosate.

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## Bacteria-nanoparticle interactions in the context of nanofouling

**Authors:** Deschenes L, Ells T

**Source:** ADVANCES IN COLLOID AND INTERFACE SCIENCE 277:102106, 2020, DOI: 10.1016/j.cis.2020.102106

**Abstract:** The attachment of microbial communities to surfaces is a well-known problem recognized to be involved in a variety of critical issues in the sectors of food processing, chronic

wounds, infection from implants, clogging of membranes and corrosion of equipment. Considering the importance of the detrimental impact of biofouling, it has received much attention in the scientific community and from concerned stakeholders. With the development of nanotechnology and the nowadays widespread use of engineered nanoparticles (ENPs), concerns have been raised regarding their fate in terrestrial and aquatic environments. Safety aspects and public health issues are critical in the management of handling nanomaterials and their nanowastes. The interactions of various types of nanoparticles (NPs) with planktonic bacteria have also received attention due to their antimicrobial properties. However, their behavior in regard to biofilms is not well understood although, in the environment, most of the bacteria prefer living in sessile communities. The question appears relevant considering the need to build knowledge on the fate of nanoparticles and the fact that no one can exclude the risk of accumulation of nanoparticles in biofilms and on surfaces leading to a form of nanofouling involving both engineered nanoparticles (ENPs) and nanoplastics. The present analysis of recent research accounts allows in identifying that (1) research activities related to water remediation systems have been mostly oriented on the impact of NPs on pre-existing biofilms, (2) experimental designs are restricted to few scenarios of exposure, usually limited to relative short-time periods although nanofouling could favour the development of multi-resistant bacterial species through sub-lethal exposures over prolong periods of time (3) nanofouling in other systems in which biofilms develop remains to be addressed, and (4) new research directions are required for investigating the mechanisms involved and the subsequent impact of nanofouling on bacterial consortium responses encountered in a variety of environments such as those prevailing in food production/processing settings. Finally, this review aims at providing recent information and insights on nanoparticle-bacterial interactions in the context of biofilms in order to supply an updated outlook of research perspectives that could help establish the framework for production, use and fate of nanomaterials as well as future research directions.

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## Effect of trace metals on growth performance and accumulation
## of lipids, proteins, and carbohydrates on the green microalga *Scenedesmus obliquus*

**Authors:** de Oliveira CYB, Viegas TL, da Silva MFO, Fracalossi DM, Lopes RG, Derner RB

**Source:** AQUACULTURE INTERNATIONAL Early Access, 2020, DOI: 10.1007/s10499-020-00533-0

**Abstract:** Microalgae biomass is considered one of the most promising raw materials for the development of high commercial value products, mainly because they are potential sources of proteins, lipids, carbohydrates, and vitamins. In this way, the optimization of culture medium of these microorganisms can help to reduce production costs, making final products more accessible. In this sense, the present study aimed to investigate the effect of different trace metal concentrations on growth and biochemical composition of *Scenedesmus obliquus*. Cultures of S. obliquus were performed using the LCA-AD medium (pH 7.6), in 2-L cylindrical borosilicate glass flasks that were constantly stirred by bubbling 0.7% CO2 enriched air (v/v), irradiance ranging from 520 to 1200 µmols m-2 s-1, and temperature at 22 ± 1 degrees C. Four trace metal concentrations were tested: control (standard concentration used on Bold's Basal Medium), ten (10(-1)), hundred (10(-2)), and thousand (10(-3)) times less than control. The trace metal concentration did not significantly affect the growth of S. obliquus - all treatments have reached about 4.2 g L-1 on the tenth day of cultivation. As well for growth performance, no significant differences were observed among the treatments for biomass composition percentages. The dry S. obliquus biomass was mainly composed of carbohydrates (about 65%), crude protein (about 20%), and finally lipids (about 12%). These findings suggest that up to 1000-fold reduction in trace metal concentration does not affect the growth and biochemical composition of the green microalga S. obliquus.

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## Effects of elutriates from contaminated coastal sediments on different life

## cycle phases of planktonic diatoms

**Authors:** Pelusi A, Rotolo F, Gallo A, Ferrante MI, Montresor M

**Source:** MARINE ENVIRONMENTAL RESEARCH 155:UNSP 104890, 2020, DOI: 10.1016/j.marenvres.2020.104890

**Abstract:** We assessed the effects of elutriates from sediments collected at three stations in the polluted Bay of Bagnoli-Coroglio along the Campania coast (Tyrrhenian Sea, Italy) using three planktonic diatoms regularly occurring in the area, *Pseudo-nuzschia multismiata*, *P. arenysensis* and *Chaetoceros socialis*. Specifically, we tested the production of sexual stages in the heterothallic Pseudo-niizschia species with the hypothesis that pollutants could impair sexual reproduction. We also tested the seeding capacity of spores of *C. socialis* after up to six months of storage in elutriates, assuming that pollutants could affect the capability of resting stages to germinate. Elutriate from station 56, with the highest concentrations of pollutants, impaired growth, sexual reproduction and spore germination. Elutriates from stations 25 and 84 caused moderate enhancement of growth and sexual reproduction in *Pseudo-nitzschia* as compared with control conditions, and also had intermediate effect on spore seeding capacity.

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## Quantitative proteomic analysis provides insights into the algicidal mechanism of Halobacillus sp. P1 against the marine diatom *Skeletonema costatum*

**Authors:** Zhang SF, Han BB, Wu FX, Huang HH

**Source:** SCIENCE OF THE TOTAL ENVIRONMENT 717:137048, 2020, DOI: 10.1016/j.scitotenv.2020.137048
**Abstract:** Algicidal behavior is a common interaction between marine microalgae and bacteria, especially in the dissipationphase of algal blooms. The marine bacterium *Halobacillus* sp. P1 was previously isolated and exhibits high algicidal activity against the diatom *Skeletonema costatum*. However, little is known about the mechanism underlying this algicidal process. Here, a tandem mass tag (TMT)-based proteomic approach was coupled with physiological analysis to investigate the cellular responses of *S. costatum* when treated with P1 culture supernatant. Among the 4582 proteins identified, 82 and 437 proteins were differentially expressed after treatment for 12 and 24 h, respectively. The proteomic results were in accordance with the results of verification by parallel reaction monitoring (PRM) assays. Proteins involved in reactive oxygen species scavenging, protein degradation and transport were upregulated, while proteins participating in nitrogen metabolism, protein translation, photosynthetic pigment biosynthesis and cell cycle regulation were significantly downregulated (p-value =0.05), corresponding to the increasing malondialdehyde content and the decreasing nitrogen, protein and chlorophyll a contents. A nutrient competitive relationship might exist between the bacterium P1 and *S. costatum*, and the inhibition of nitrogen metabolism by the P1 culture supernatant might be the key lethal factor that results in the dysfunction of *S. costatum* metabolism. Our study sheds light on the algicidal mechanism of P1 at the molecular level and provides new insights into algae-bacteria interactions.

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Influence of multi-walled carbon nanotubes on the microbial biomass, enzyme activity, and bacterial community structure in 2,4-dichlorophenol-contaminated sediment

**Authors:** Song B, Gong JL, Tang WW, Zeng GM, Chen M, Xu P, Shen MC, Ye SJ, Feng HP, Zhou CY, Yang Y

**Source:** SCIENCE OF THE TOTAL ENVIRONMENT
713:136645, 2020, DOI:
10.1016/j.scitotenv.2020.136645

**Abstract:** The rise in manufacture and use of carbon nanotubes has aroused the concern about their potential risks associated with coexisting pollutants in the aquatic environment. 2,4-dichlorophenol (2,4-DCP), with a high toxicity to many aquatic organisms, is a widespread pollutant resulting from the extensive use of pesticides and preservatives. In this article, the adsorption of 2,4-DCP by riverine sediment and the responses of sediment microbial community to 2,4-DCP were studied in the presence of multi-walled carbon nanotubes (MWCNTs). Adding MWCNTs significantly increased the adsorption amount of sediment for 2,4-DCP from 0.541 to 1.44 mg/g as the MWCNT concentration increased from 0 to 15 mg/g. The responses of sediment microbial community were determined after one-month exposure to MWCNTs at different concentrations (0.05, 0.5, 5, and 50 mg/g). The microbial biomass carbon in the sediment contaminated with 2,4-DCP increased in the presence of 5 mg/g of MWCNTs (from 0.06 to 0.11 mg/g), but not significantly changed at other MWCNT concentrations. For the sediments contaminated with 2,4-DCP, the presence of MWCNTs made no difference to urease activity, while the dehydrogenase activity slightly increased with the addition of 5 mg/g of MWCNTs and decreased in the presence of 50 mg/g of MWCNTs. The changes of sediment bacterial communities were further determined by 16S rRNA gene sequencing. Based on the weighted UniFrac distance between communities, the clustering analysis suggested that the contamination of 2,4-DCP affected the bacterial community structure in a greater degree than that caused by MWCNTs at relatively low concentrations (≤ 5 mg/g). Bacteroidetes, Planctomycetes, and Nitrospirae were feature bacterial phyla to reflect the effects of MWCNTs and 2,4-DCP on sediment bacterial community. These results may contribute to the understanding of microbial community response to co-exposure of MWCNTs and 2,4-DCP and the assessment of associated ecological risks.

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Periphytic biofilm: An innovative approach for
## biodegradation of microplastics

**Authors:** Shabbir S, Faheem M, Ali N, Kerr PG, Wang LF, Kuppusamy S, Li Y

**Source:** SCIENCE OF THE TOTAL ENVIRONMENT 717:137064, 2020, DOI: 10.1016/j.scitotenv.2020.137064

**Abstract:** Microplastics (MPs) have been gaining the attention of environmental researchers since the 1960s anecdotal reports of plastic entanglement and ingestion by marine creatures. Due to their increasing accretion in aquatic environments, as well as resistance towards degradation, marine litter research has focused on microplastics more recently. In the present study, a relatively new method of biodegradation was implemented for the biodegradation of three structurally different MPs i.e. polypropylene (PP), polyethylene (PE) and polyethylene terephthalate (PET). Periphytic biofilm was used for this purpose in various backgrounds of carbon sources (glucose, peptone, and glucose and peptone). Biodegradation of MPs was estimated in terms of weight loss. It was observed that the addition of glucose enhanced the biodegradation of MI's by periphyton biofilm for all MPs (from 9.52%-18.02%, 5.95%-14.02% and 1324-19.72% for PP, PE and PET respectively) after 60 days compared to natural biofilm alone. To the contrary, peptone, and glucose and peptone together, were inhibitory. Biodegradation was further confirmed by morphological changes observed using SEM, MR spectra and GPC lent further support to the results whereby new peaks appeared along with reduction in old peaks and decrease in peak intensities. MiSeq sequencing shows that *Deinococcus-thermus*; Proteobacteria; Cyanobacteria are the dominant phyla in natural biofilms, and their relative abundances increase after the addition of glucose. However, the abundances shifted to *Deinococcus-thermus*; Cyanobacteria; Firmicutes; Bacteroidetes, when the biofilms were treated with either peptone alone, or with glucose and peptone together. Therefore, the change in biodegradation capability also be due to the change in the microbial community structures after addition of the C-sources. These experiments provide an innovative approach towards effective biodegradation of MPs using a relatively new environment-friendly method.

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## Ecotoxicity of polyethylene nanoplastics from the North Atlantic oceanic gyre on freshwater and marine organisms (microalgae and filter-feeding bivalves)

**Authors:** Baudrimont M, Arini A, Guegan C, Venel Z, Gigault J, Pedrono B, Prunier J, Maurice L, Ter Halle A, Feurtet-Mazel A

**Source:** ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH 27(4):3746-3755, 2020, DOI: 10.1007/s11356-019-04668-3

**Abstract:** Each year, 5 to 10 million tons of plastic waste is dumped in the oceans via freshwaters and accumulated in huge oceanic gyres. Under the effect of several abiotic factors, macro plastic wastes (or plastic wastes with macro sizes) are fractionated into microplastics (MP) and finally reach the nanometric size (nanoplastic NP). To reveal potential toxic impacts of these NPs, two microalgae, *Scenedemus subspicatus* (freshwater green algae), and *Thalassiosira weissiflogii* (marine diatom) were exposed for up to 48 h at 1, 10, 100, 1000, and 10,000 µg/L to reference polyethylene NPs (PER) or NPs made from polyethylene collected in the North Atlantic gyre (PEN, 7th continent expedition in 2015). Freshwater filter-feeding bivalves, *Corbicula fluminea*, were exposed to 1000 µg/L of PER and PEN for 48 h to study a possible modification of their filtration or digestion capacity. The results show that PER and PEN do not influence the cell growth of *T. weissiflogii*, but the PEN exposure causes growth inhibition of *S. subspicatus* for all exposure concentrations tested. This growth inhibition is enhanced for a higher concentration of PER or PEN (10,000 µg/L) in *S. subspicatus*. The marine diatom *T. weissiflogii* appears to be less impacted by plastic pollution than the green algae *S. subspicatus* for the exposure time. Exposure to NPs does not lead to any alteration of bivalve filtration; however, fecal and pseudo-fecal production increased after PEN exposure, suggesting the implementation of rejection mechanisms for inedible particles.

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## Evolution and distribution of resistance genes and
## bacterial community in water and biofilm of a simulated fish-duck integrated pond with stress

**Authors:** Zhou M, Xu YB, Ouyang PQ, Ling JY, Cai QJ, Huang L, Zhou X, Zheng L

**Source:** CHEMOSPHERE 245:UNSP 125549, 2020, DOI: 10.1016/j.chemosphere.2019.125549

**Abstract:** Integrated fish-duck pond is a common circular farming model in South China, besides, it is also hot-spot for the co-selection of antibiotic resistance genes (ARGs). The aim of this study was to investigate the effects of duck manure, As and cefotaxime on the bacterial community, and the evolution and distribution of ARGs and metal(loid) resistance genes (MRGs) in water and biofilm. Five groups of fish tanks included a control and four test groups. The experimental period lasted for 100 days. Six ARGs (CIT, DHA, EBC, FOX, MOX, TEM), two MRGs (arsB, arsC), and two integron genes (intl1,urpose and detected in water and biofilm. The results showed that duck manure brought ARGs and MRGs into fish tanks. Stress factors (cefotaxime, As) increased the relative abundance of resistance genes, and this was positively correlated with stress concentrations. The biofilm was visible significantly at the end of stage 3, and the total relative abundance of resistance genes in biofilm was higher than water from stage 5 onwards. Evolution of AmpC beta-lactamase resistance genes was more obvious than MRGs, especially for MOX, which increased by 3 orders of magnitude. The abundance of Flavobacterium was higher in biofilm than in water. Moreover, correlation analysis showed that both arsB and MOX were significantly correlated withurpose and those to ions was the accumulation of fatty acids oxidation products: particles caused higher fold changes (particles/ions ratio 1.9-3.0) at 1 mg/L and lower fold changes (particles/ions ratio 0.4-0.7) at 10 mg/L compared with ions. Compared with microparticles, there was no nanoparticle-specific pathway perturbed. These results confirm the predominant role of dissolved Cu ions on the toxicity of CuO NPs and MPs, and also reveal particle-specific toxicity from a metabolomics perspective.

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A global metabolomic insight into the oxidative stress and membrane damage of copper oxide nanoparticles and

## microparticles on microalga *Chlorella vulgaris*

**Authors:** Wang L, Huang XL, Sun WL, Too HZ, Laserna AKC, Li SFY

**Source:** ENVIRONMENTAL POLLUTION 258:113647, 2020, DOI: 10.1016/j.envpol.2019.113647

**Abstract:** To compare aquatic organisms' responses to the toxicity of copper oxide (CuO) nanoparticles (NPs) with those of CuO microparticles (MPs) and copper (Cu) ions, a global metabolomics approach was employed to investigate the changes of both polar and nonpolar metabolites in microalga *Chlorella vulgaris* after 5-day exposure to CuO NPs and MPs (1 and 10 mg/L), as well as the corresponding dissolved Cu ions (0.08 and 0.8 mg/L). Unchanged growth, slight reactive oxygen species production, and significant membrane damage (at 10 mg/L CuO particles) in *C. vulgaris* were demonstrated. A total of 75 differentiated metabolites were identified. Most metabolic pathways perturbed after CuO NPs exposure were shared by those after CuO MPs and Cu ions exposure, including accumulation of chlorophyll intermediates (max. 2.4-5.2 fold), membrane lipids remodeling for membrane protection (decrease of phosphatidylethanolamines (min. 0.6 fold) and phosphatidylcholines (min. 0.2-0.7 fold), as well as increase of phosphatidic acids (max. 1.5-2.9 fold), phosphatidylglycerols (max. 2.2-2.3 fold), monogalactosyldiacylglycerols (max. 1.2-1.4 fold), digalactosylmonoacylglycerols (max. 1.9-3.8 fold), diacylglycerols (max. 1.4 fold), lysophospholipids (max. 1.8-3.0 fold), and fatty acids (max. 3.0-6.2 fold)), perturbation of glutathione metabolism induced by oxidative stress, and accumulation of osmoregulants (max. 1.3-2.6 fold) to counteract osmotic stress. The only difference between metabolic responses to particles and those to ions was the accumulation of fatty acids oxidation products: particles caused higher fold changes (particles/ions ratio 1.9-3.0) at 1 mg/L and lower fold changes (particles/ions ratio 0.4-0.7) at 10 mg/L compared with ions. Compared with microparticles, there was no nanoparticle-specific pathway perturbed. These results confirm the predominant role of dissolved Cu ions on the toxicity of CuO NPs and MPs, and also reveal particle-specific toxicity from a metabolomics perspective.

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# Toxicity, Biodegradation, and Metabolic Fate of Organophosphorus Pesticide Trichlorfon on the Freshwater Algae *Chlamydomonas reinhardtii*

**Authors:** Wan L, Wu YX, Ding HJ, Zhang WH

**Source:** JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 68(6):1645-1653, 2020, DOI: 10.1021/acs.jafc.9b05765

**Abstract:** This study investigated the toxicity of trichlorfon (TCF) to the freshwater algae *Chlamydomonas reinhardtii*, as well as its biodegradation and metabolic fate. The growth of *C. reinhardtii* decreased with increasing TCF concentration, and the maximum inhibition ratio was 51.3% at 200 mg L-1 TCF compared to the control. (...) The variations in pH during cultivation suggested that photosynthetic microalgae have innate advantages over bacteria and fungi in remediating TCF. A 100% biodegradation rate was achieved at a maximum concentration of 100 mg L-1 TCF. Ten metabolites were identified by GC-MS, and the degradation pathways of TCF by the algae were proposed. This research demonstrated that *C. reinhardtii* is highly tolerant to and can efficiently degrade TCF. Thus, *C. reinhardtii* can be used to remove traces of TCF from natural water environments and to treat TCF-contaminated wastewater.

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# Differential responses of two cyanobacterial species to R-metalaxyl toxicity: Growth, photosynthesis and antioxidant analyses

**Authors:** Hamed SM, Hassan SH, Selim S, Wadaan MAM, Mohany M, Hozzein WN, AbdElgawad H

**Source:** ENVIRONMENTAL POLLUTION 258:113681, 2020, DOI: 10.1016/j.envpol.2019.113681

**Abstract:** Metalaxyl is a broad-spectrum chiral fungicide that used for the protection of plants, however extensive use of metalaxyl resulted in serious environmental problems. Thus, a study on

the detoxification mechanism in algae/cyanobacteria and their ability for phycoremediation is highly recommended. Here, we investigated the physiological and biochemical responses of two cyanobacterial species; *Anabaena laxa* and *Nostoc muscorum* to R-metalaxyl toxicity as well as their ability as phycoremediators. Two different levels of R-metalaxyl, at mild (10 mg/L) and high dose (25 mg/L), were applied for one-week. We found that *A. laxa* absorbed and accumulated more intracellular R-metalaxyl compared to *N. muscorum*. R-metalaxyl, which triggered a dose-based reduction in cell growth, photosynthetic pigment content, and photosynthetic key enzymes activities i.e., phosphoenolpyruvate carboxylase (PEPC) and ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCo). These decreases were significantly less pronounced in *A. laxa*. On the other hand, R-metalaxyl significantly induced oxidative damage markers, e.g., H2O2 levels, lipid peroxidation (MDA), protein oxidation and NADPH oxidase activity. However, these increases were also lower in *A. laxa* compared to *N. muscorum*. To alleviate R-metalaxyl toxicity, *A. laxa* induced the polyphenols, flavonoids, tocopherols and glutathione (GSH) levels as well as peroxidase (POX), glutathione peroxidase (GPX), glutathione reductase (GR) and glutathione-s-transferase (GST) enzyme activities. On the contrary, the significant induction of antioxidants in *N. muscorum* was restricted to ascorbate, catalase (CAT) and ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR) enzyme activities. Although *A. laxa* accumulated more R-metalaxyl, it experienced less stress due to subsequent induction of antioxidants. Therefore, *A. laxa* may be a promising R-metalaxyl phycoremediator. Our results provided basic data for understanding the ecotoxicology of R-metalaxyl contamination in aquatic habitats and the toxicity indices among cyanobacteria.

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# Aluminium triggers oxidative stress and antioxidant response in the microalgae *Scenedesmus* sp

**Authors:** Ameri M, Baron-Sola A, Khavari-Nejad RA, Soltani N, Najafi F, Bagheri A, Martinez F, Hernandez LE
**Source:** JOURNAL OF PLANT PHYSIOLOGY
246:153114, 2020,
DOI:10.1016/j.jplph.2020.153114

**Abstract:** Aluminium (Al) water pollution is an increasing environmental problem and comprehensive analysis of toxic responses of aquatic primary producer organisms is imperative. We characterized the antioxidant response of Scenedesmus sp. microalga to Al-induced oxidative stress. After 72 h of exposure to Al (0, 10, and 100 µM) in a modified Bold Basal Medium (pH 5.0), we observed cell aggregation and alterations in the subcellular structure, strong lipid peroxidation and oxidative stress induction (detected with the fluorescent probe 2',7'-dichlorodihydrofluorescein diacetate) in parallel with Al accumulation in cells. At the same time, Al toxicity caused depletion of important macronutrients like Ca, which is important for cell-wall structure. Analysis of antioxidant enzymatic activities in Al-treated Scenedesmus cells revealed that catalase, ascorbate peroxidase, as well as different isoforms of superoxide dismutase were inhibited especially at the highest Al dose (100 µM), cells that accumulated the highest concentration of Al. On the other hand, glutathione reductase activity increased at that Al concentration. Immunodetection after Western blotting confirmed that only ascorbate peroxidase inhibition was apparently due to a decrease in enzyme levels. However, the inhibition of catalase and activation of glutathione reductase activities seemed related with post-translational modifications in protein function as protein expression decreased or increased, respectively under Al stress. Our results may help to understand toxic mechanisms triggered by Al in freshwater microalgae, which in turn could aid to select suitable biomarkers of Al contamination in aquatic ecosystems.

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## Spatial distribution characteristics of bacterial community structure and gene abundance in sediments of the Bohai Sea

**Authors:** Chen QR, Fan JF, Su J, Ming HX, Sun ZH, Li MF, Zhao XH, Wang YT, Zhang YX, Zhang HZ, Jin Y, Ma XW, Wang B

**Source:** ACTA OCEANOLOGICA SINICA 39(2):69-78, 2020, DOI: 10.1007/s13131-020-1554-8

**Abstract:** This study investigated differences in the community structure and environmental responses of the bacterial community in sediments of the Bohai Sea. (...) The results showed that sediments at the majority of the 13 sampling stations were contaminated by heavy metal mercury. The main phyla of bacteria recorded included Proteobacteria (52.92%), Bacteroidetes (11.76%), Planctomycetes (7.39%), Acidobacteria (6.53%) and Chloroflexi (4.97%). The genus with the highest relative abundance was Desulfobulbus (4.99%), which was the dominant genus at most sampling stations, followed by Lutimonas and Halioglobus. The main factors influencing bacterial community structure were total organic carbon, followed by depth and total phosphorus. The content of lead, cadmium, chromium, copper and zinc had a consistent effect on community structure. Arsenic showed a negative correlation with bacterial community structure in most samples, while the impact of mercury on community structure was not significant. The bacterial community in sediment samples from the Bohai Sea was rich in diversity and displayed an increase in diversity from high to low latitudes. The data indicated that the Bohai Sea had abundant microbial resources and was rich in bacteria with the potential to metabolize many types of pollutants.

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## Silver nanoparticle and Ag+-induced shifts of microbial communities in natural brackish waters: Are they more pronounced under oxic conditions than anoxic conditions?

**Authors:** Zou XY, Li PH, Wang XD, Zheng SH, Dai FQ, Zhang HW

**Source:** ENVIRONMENTAL POLLUTION 258:113686, 2020, DOI: 10.1016/j.envpol.2019.113686

**Abstract:** With the burst of silver nanoparticles (AgNPs) applications, their potential entry into the environment has attracted increasing concern. To date, researches about the impacts of AgNPs on microbial communities have been
scarcely conducted in the brackish waters. Here, the effects of interactions of AgNPs and Ag⁺ (as a positive control) with dissolved oxygen on natural brackish water microbial communities were investigated for 30 d. The introduction of AgNPs and Ag⁺ in natural brackish waters resulted in distinct bacterial community composition and structure as well as reduction of the richness and diversity, effects that were not eliminated completely during the tested periods. Anoxic conditions could attenuate the effects of AgNPs and Ag⁺ on the community, and dissolved oxygen made more contributions to community compositions for short-term exposure. High doses of AgNPs had more pronounced long-term impacts than Ag⁺ amendment. Compared with the controls, two general AgNP and Ag⁺ responses, namely, sensitivity and resistance, were observed. Sensitive species mainly included those of the genera Synechococcus and unclassified f_Rhodobacteraceae, while resistant species mostly belonged to the phylum Bacteroidetes and participated in carbon metabolic processes. Our results indicated that the microbial communities that were involved in nutrient cycles (such as carbon, nitrogen, and sulfide) and photoautotrophic bacteria that contained bacteriochlorophyll were adversely affected by AgNPs and Ag⁺. In addition, dissolved oxygen could further change the microbial communities. These results implied that under different oxygen conditions AgNPs possibly resulted in varying microbial survival strategies and affected the biogeochemical cycling of nutrients in natural brackish waters.

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## Enhanced bactericidal effect of ceftriaxone drug encapsulated in nanostructured lipid carrier against gram-negative Escherichia coli bacteria: drug formulation, optimization, and cell culture study

Authors: Ebrahimi S, Farhadian N, Karimi M, Ebrahimi M

Source: ANTIMICROBIAL RESISTANCE AND INFECTION CONTROL 9(1):28, 2020, DOI: 10.1186/s13756-020-0690-4

**Abstract:** Background Ceftriaxone is one of the most common types of antibiotics used to treat most deadly bacterial infections. One way to alleviate the side effects of medication is to reduce drug consumption by changing the ordinary drug forms into nanostructured forms. In this study, a nanostructured lipid carrier (NLC) containing hydrophilic ceftriaxone sodium drug is developed, and its effect on eliminating gram-negative bacteria Escherichia coli death is investigated. Methods Double emulsion solvent evaporation method is applied to prepare NLC. Mathematical modeling based on the solubility study is performed to select the best materials for NLC preparation. Haftyzer-Van Krevelen and Hoy's models are employed for this purpose. Drug release from optimized NLC is examined under in vitro environment. Then, the efficacy of the optimized sample on eliminating gram-negative bacteria Escherichia coli is investigated. Results Mathematical modeling reveals that both methods are capable of predicting drug encapsulation efficiency trends by chaining solid and liquid lipids. However, Haftyzer-Van Krevelen's method can precisely predict the particle size trend by changing the surfactant types in water and oily phases of emulsions. The optimal sample has a mean particle size of 86 nm and drug entrapment efficiency of 83%. Also, a controlled drug release in prepared nanostructures over time is observed under in-vitro media. The results regarding the effectiveness of optimized NLC in killing Escherichia coli bacteria suggests that by cutting drug dosage of the nanostructured form in half, an effect comparable to that of free drug can be observed at longer times. Conclusion Results confirm that NLC structure is an appropriate alternative for the delivery of ceftriaxone drug with a controlled release behavior.

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## Combating the prevalence of water-borne bacterial pathogens using anisotropic structures of silver nanoparticles

Authors: Ali HR, Emam AN, Koraney NF, Hefny EG, Ali SF
**Source:** JOURNAL OF NANOPARTICLE RESEARCH 22(2):47, 2020, DOI: 10.1007/s11051-020-4760-6

**Abstract:** The current study aimed to investigate the antibacterial activity of different anisotropic structures of silver nanoparticles in the hexagon and spherical shapes against MDR-bacteria isolated from water sources in Egypt. The water samples collected from four different dairy farm-related sites were tested bacteriologically, followed by identification of the antibiotic-resistant profile for the isolates. The result revealed that Enterococcus spp, Proteus spp, and E. coli spp are the most common organisms in all tested water samples, and the antibiotic-resistant profile identified 11/13 waterborne isolates as MDR-bacteria. Herein, spherical and hexagonal silver nanoparticles were prepared with an average size of 26 ± 6 nm and 375 ± 80 nm, respectively, through the chemical reduction method. Further, MDR gram-positive (Enterococcus) and MDR gram-negative (E. coli) were selected for studying the antibacterial property of the synthesized AgNPs using agar well diffusion method. In another experiment, microdilution broth assay coupled with XTT assay is optimized for facilitating the testing of a broad range of AgNPs concentrations efficiently without the need for laborious preparation of the colony counting method. Our results indicated that AgNPs in spherical and hexagonal shapes are potent antibacterial against the MDR-waterborne bacteria in a dose and shape-dependent manner. The hexagonal AgNPs (h-AgNPs) express higher bactericidal activity when compared to spherical AgNPs (AgNSs) against the two tested MDR-bacteria, but the E. coli isolate more sensitive to both tested shapes of AgNPs than the Enterococcus isolate. The results recommend that AgNPs can be used as efficient growth inhibitors for water-borne bacterial pathogens, making them applicable to various water filters and antimicrobial applications.

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Insights into the
transcriptional responses of a
microbial community to silver
nanoparticles in a freshwater
microcosm

**Authors:** Lu T, Qu Q, Lavoie M, Pan XJ, Peijnenburg WJGM, Zhou ZG, Pan XL, Cai ZQ, Qian HF

**Source:** ENVIRONMENTAL POLLUTION 258:113727, 2020, DOI: 10.1016/j.envpol.2019.113727

**Abstract:** Silver nanoparticles (AgNPs) are widely used because of their excellent antibacterial properties. They are, however, easily discharged into the water environment, causing potential adverse environmental effects. Meta-transcriptomic analyses are helpful to study the transcriptional response of prokaryotic and eukaryotic aquatic microorganisms to AgNPs. In the present study, microcosms were used to investigate the toxicity of AgNPs to a natural aquatic microbial community. It was found that a 7-day exposure to 10 µg L-1 silver nanoparticles (AgNPs) dramatically affected the structure of the microbial community. Aquatic micro eukaryota (including eukaryotic algae, fungi, and zooplankton) and bacteria (i.e., heterotrophic bacteria and cyanobacteria) responded differently to the AgNPs stress. Meta-transcriptomic analyses demonstrated that eukaryota could use multiple cellular strategies to cope with AgNPs stress, such as enhancing nitrogen and sulfur metabolism, over-expressing genes related to translation, amino acids biosynthesis, and promoting bacterial-eukaryotic algae interactions. By contrast, bacteria were negatively affected by AgNPs with less signs of detoxification than in case of eukaryota: various pathways related to energy metabolism, DNA replication and genetic repair were seriously inhibited by AgNPs. As a result, eukaryotic algae (mainly Chlorophyta) dominated over cyanobacteria in the AgNPs treated microcosms over the 7-d exposure. The present study helps to understand the effects of AgNPs on aquatic microorganisms and provides insights into the contrasting AgNPs toxicity in eukaryota and bacteria.

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Growth inhibition of
eutrophication water by
white-rot fungus

**Authors:** Zeng GM, Zhang ML, Wang YL, Wang P, Wu P, Li X, Wen X

**Source:** FRESENIUS ENVIRONMENTAL BULLETIN 29(2):743-748, 2020
**Abstract:** It is important to inhibit Algal blooms by efficacy methods, which is caused water stench and threaten human health seriously. The strain of white-rot fungus may be one of the bio-treatment ways to do this, in particular, the Phanerochaete chrysosporium. Its algicidal ability on algae was studied by three main influence factors: white rot fungus dosage, pH value and DO. The results showed that the chlorophyll-a content of eutrophication water decreased 92.24% within 24 h under the optimum conditions that 250 mg/L at pH 7.0 for 7.0 mg/L. Pre-treated eutrophication water was investigated by algal cells dehydrogenase activity, soluble protein content and malondialdehyde. It was seen that decrease in algal cells dehydrogenase activity and soluble protein content and an increase in MDA content, which were associated with the decrease in chlorophyll-a content. These results indicated that the fungus could destroy the algal cell and inhibit the algae blooms.

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## Inhibitory efficacy of white-rot fungus against harmful freshwater algal bloom species

**Authors:** Zeng GM, Zhang ML, Wang YL, Wang P, Wu P, Li X, Wen X

**Source:** FRESENIUS ENVIRONMENTAL BULLETIN 29(2):749-755, 2020

**Abstract:** Eutrophication and frequent algal blooms have become serious ecological problems. White-rot fungi have been considered as possible microorganisms for controlling algal blooms. In this study, *Cryptomonas obovata* FACHB-1301, *Oscillatoria* sp. FACHB-1083, and *Scenedesmus quadricauda* FACHB-507 co-cultured with the white-rot fungus *Phanerochaete chrysosporium*. All algal cells were damaged within 48 h of coculture. *P. chrysosporium* apparently decreased the chlorophyll-a content, dehydrogenase activity, and soluble protein content but increased the malondialdehyde content of the algal cells. These results indicate that the algae

were greatly inhibited and severely damaged by the fungus. In conclusion, P. chrysosporium can effectively remove algal cells and inhibit algal blooms.

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## Microbial Colonization in Marine Environments: Overview of Current Knowledge and Emerging Research Topics

**Author:** Caruso G

**Source:** JOURNAL OF MARINE SCIENCE AND ENGINEERING 8(2):78, 2020, DOI: 10.3390/jmse8020078

**Abstract:** Microbial biofilms are biological structures composed of surface-attached microbial communities embedded in an extracellular polymeric matrix. In aquatic environments, the microbial colonization of submerged surfaces is a complex process involving several factors, related to both environmental conditions and to the physical-chemical nature of the substrates. Several studies have addressed this issue; however, more research is still needed on microbial biofilms in marine ecosystems. After a brief report on environmental drivers of biofilm formation, this study reviews current knowledge of microbial community attached to artificial substrates, as obtained by experiments performed on several material types deployed in temperate and extreme polar marine ecosystems. Depending on the substrate, different microbial communities were found, sometimes highlighting the occurrence of species-specificity. Future research challenges and concluding remarks are also considered. Emphasis is given to future perspectives in biofilm studies and their potential applications, related to biofouling prevention (such as cell-to-cell communication by quorum sensing or improved knowledge of drivers/signals affecting biological settlement) as well as to the potential use of microbial biofilms as sentinels of environmental changes and new candidates for bioremediation purposes.

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# Marine Actinobacteria: Screening for Predation Leads to the Discovery of Potential New Drugs against Multidrug-Resistant Bacteria

**Authors:** Ibrahimi M, Korichi W, Hafidi M, Lemee L, Ouhdouch Y, Loqman S

**Source:** ANTIBIOTICS-BASEL 9(2):91, 2020, DOI: 10.3390/antibiotics9020091

**Abstract:** Predatory bacteria constitute a heterogeneous group of prokaryotes able to lyse and feed on the cellular constituents of other bacteria in conditions of nutrient scarcity. In this study, we describe the isolation of Actinobacteria predator of other bacteria from the marine water of the Moroccan Atlantic coast. Only 4 Actinobacteria isolates showing strong predation capability against native or multidrug-resistant Gram-positive or Gram-negative bacteria were identified among 142 isolated potential predatory bacteria. These actinobacterial predators were shown to belong to the Streptomyces genus and to inhibit the growth of various native or multidrug-resistant micro-organisms, including *Micrococcus luteus*, *Staphylococcus aureus* (native and methicillin-resistant), and *Escherichia coli* (native and ampicillin-resistant). Even if no clear correlation could be established between the antibacterial activities of the selected predator Actinobacteria and their predatory activity, we cannot exclude that some specific bio-active secondary metabolites were produced in this context and contributed to the killing and lysis of the bacteria. Indeed, the co-cultivation of Actinobacteria with other bacteria is known to lead to the production of compounds that are not produced in monoculture. Furthermore, the production of specific antibiotics is linked to the composition of the growth media that, in our co-culture conditions, exclusively consisted of the components of the prey living cells. Interestingly, our strategy led to the isolation of bacteria with interesting inhibitory activity against methicillin-resistant S. aureus (MRSA) as well as against Gram-negative bacteria.

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# Water environments: metal-tolerant and antibiotic-resistant bacteria

**Author:** Squadrone S

**Source:** ENVIRONMENTAL MONITORING AND ASSESSMENT 192(4):238, 2020, DOI: 10.1007/s10661-020-8191-8

**Abstract:** The potential threat of both metals and antibiotics to the environment and human health has raised significant concerns in the last decade. Metal-resistant and antibiotic-resistant bacteria are found in most environments, including water, and the risk posed to humans and animals due to the spread of antibiotic-resistant bacteria and antibiotic-resistant genes in the environment is increasing. Bacteria have developed the ability to tolerate metals even at notable concentrations. This ability tends to favor the selection of antibiotic-resistant strains, even in pristine water environments, with the potential risk of spreading this resistance to human pathogens. In this mini-review, we focus on investigations performed in marine and freshwater environments worldwide, highlighting the presence of co-resistance to metals and antibiotics.

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# Simultaneous enhancement of heavy metal removal and electricity generation in soil microbial fuel cell

**Authors:** Zhang JR, Cao X, Wang H, Long XZ, Li XN

**Source:** ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 192, 2020, DOI: 10.1016/j.ecoenv.2020.110314

**Abstract:** As an environmentally sustainable bioelectrochemical technology, the microbial fuel cell (MFC) has attracted great attention. In this study, a three-chamber MFC (TC-MFC) was enhanced with different auxiliary reagents to remove heavy metals from soil. The results showed that the removal efficiency of heavy metals from soil increased with increasing auxiliary reagent concentration. When 1 mol/L citric acid, HCl, or acetic acid were used as an auxiliary reagent, the total copper (500 mg/kg)
removal efficiency after 74 days of TC-MFC treatment was 3.89, 5.01 and 2.01 times that of the control group, respectively. The highest soil electrical conductivity (15.29 ms/cm), ionic heavy metal content (94.78%), electricity generation performance (363.04 mW h), and desorption stability of heavy metals were obtained when using 1 mol/L HCl as an auxiliary reagent, indicating that HCl was more suitable for the remediation of heavy metals in soil using a TC-MFC. Correlation analysis showed that the electricity generation of the TC-MFC was linearly related to the removal efficiency of heavy metals from soil (R² = 0.9296). At the same time, higher content of ionic heavy metals in the soil led to better migration of heavy metals under the internal electric field of the TC-MFC.

## Bioremediation of heavy metals using microalgae: Recent advances and mechanisms

**Authors:** Leong YK, Chang JS

**Source:** BIORESOURCE TECHNOLOGY 303:122886, 2020, DOI: 10.1016/j.biortech.2020.122886

**Abstract:** Five heavy metals namely, arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb) and mercury (Hg) are carcinogenic and show toxicity even at trace amounts, posing threats to environmental ecology and human health. There is an emerging trend of employing microalgae in phycoremediation of heavy metals, due to several benefits including abundant availability, inexpensive, excellent metal removal efficiency and eco-friendly nature. This review presents the recent advances and mechanisms involved in bioremediation and biosorption of these toxic heavy metals utilizing microalgae. Tolerance and response of different microalgae strains to heavy metals and their bioaccumulation capability with value-added by-products formation as well as utilization of non-living biomass as biosorbents are discussed. Furthermore, challenges and future prospects in bioremediation of heavy metals by microalgae are also explored. This review aims to provide useful insights to help future development of efficient and commercially viable technology for microalgae-based heavy metal bioremediation.

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## Bacterial Disinfection by CuFe2O4 Nanoparticles Enhanced by NH2OH: A Mechanistic Study

**Authors:** Gu Y, Xiao FR, Luo LM, Zhou XY, Zhou XD, Li J, Li Z

**Source:** NANOMATERIALS 10(1):18, 2020, DOI: 10.3390/nano10010018

**Abstract:** Many disinfection technologies have emerged recently in water treatment industry, which are designed to inactivate water pathogens with extraordinary efficiency and minimum side effects and costs. Current disinfection processes, including chlorination, ozonation, UV irradiation, and so on, have their inherent drawbacks, and have been proven ineffective under certain scenarios. Bacterial inactivation by noble metals has been traditionally used, and copper is an ideal candidate as a bactericidal agent owing to its high abundance and low cost. Building on previous findings, we explored the bactericidal efficiency of Cu(I) and attempted to develop it into a novel water disinfection platform. Nanosized copper ferrite was synthesized, and it was reduced by hydroxylamine to form surface bound Cu(I) species. Our results showed that the generated Cu(I) on copper ferrite surface could inactivate E. coli at a much higher efficiency than Cu(II) species. Elevated reactive oxygen species' content inside the cell primarily accounted for the strong bactericidal role of Cu(I), which may eventually lead to enhanced oxidative stress towards cell membrane, DNA, and functional proteins. The developed platform in this study is promising to be integrated into current water treatment industry.

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## Hierarchical Cluster Analysis of Medical Chemicals Detected by a Bacteriophage-Based Colorimetric Sensor Array

**Authors:** Kim C, Lee H, Devaraj V, Kim WG, Lee Y, Kim Y, Jeong NN, Choi EJ, Baek SH, Han DW, Sun H, Oh JW
**Source:** NANOMATERIALS 10(1):121, 2020, DOI: 10.3390/nano10010121

**Abstract:** M13 bacteriophage-based colorimetric sensors, especially multi-array sensors, have been successfully demonstrated to be a powerful platform for detecting extremely small amounts of target molecules. Colorimetric sensors can be fabricated easily using self-assembly of genetically engineered M13 bacteriophage which incorporates peptide libraries on its surface. However, the ability to discriminate many types of target molecules is still required. In this work, we introduce a statistical method to efficiently analyze a huge amount of numerical results in order to classify various types of target molecules. To enhance the selectivity of M13 bacteriophage-based colorimetric sensors, a multi-array sensor system can be an appropriate platform. On this basis, a pattern-recognizing multi-array biosensor platform was fabricated by integrating three types of sensors in which genetically engineered M13 bacteriophages (wild-, RGD-, and EEEE-type) were utilized as a primary building block. This sensor system was used to analyze a pattern of color change caused by a reaction between the sensor array and external substances, followed by separating the specific target substances by means of hierarchical cluster analysis. The biosensor platform could detect drug contaminants such as hormone drugs (estrogen) and antibiotics. We expect that the proposed biosensor system could be used for the development of a first-analysis kit, which would be inexpensive and easy to supply and could be applied in monitoring the environment and health care.

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Quantifying the
Mineralization of C-13-
Labeled Cations and Anions
Reveals Differences in
Microbial Biodegradation of
Herbicidal Ionic Liquids
between Water and Soil

**Authors:** Wilms W, Wozniak-Karczewska M, Niemczak M, Lisiecki P, Zgola-Grzeskowiak A, Lawniczak L, Framski G, Pernak J, Owsianiak M, Vogt C, Fischer A, Rogers RD, Chrzanowski L

**Source:** ACS SUSTAINABLE CHEMISTRY & ENGINEERING 8(8):3412-3426, 2020, DOI: 10.1021/acssuschemeng.9b07598

**Abstract:** Characterization of the biodegradability of herbicidal ionic liquids (HILs) using the industry standard activated sludge methodology is thought to be insufficient to fully understand the biodegradation of HILs in the environment because cations and anions of the HILs may have different potential for biodegradation in aquatic and terrestrial systems. To test this hypothesis, we conducted laboratory microcosm experiments using C-13-labeled cations and anions forming benzyldodecyldimethylammonium 4-chloro-2-methylphenoxyacetate ([C-12-BA][MCPA]) and evaluated their biodegradation potential in soil with a known history of herbicide exposure, and in water (mineral medium) augmented with microorganisms present in activated sludge. The biodegradability of the cation and anion was found to depend on the test system (water or soil). The cation was mineralized in water, whereas the anion was fully utilized in soil. These results suggest that performing biodegradation tests using differently C-13-labeled species of the target HIL and mimicking various environmental compartments (e.g., soil, activated sludge) is needed to provide a better understanding of the fate of HILs in the environment. They also indicate that biodegradation kinetic parameters of HILs derived from experiments performed in aqueous systems should not be used to estimate biodegradation rates in terrestrial environments.

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Heavy metal resistance and
metallothionein induction in
bacteria isolated from
Seybouse River, Algeria

**Authors:** Benhalima L, Amri S, Bensouilah M, Ouzrout R

**Source:** APPLIED ECOLOGY AND ENVIRONMENTAL RESEARCH 18(1):1721-1737, 2020, DOI: 10.15666/aeer/1801_17211737

**Abstract:** Heavy metal pollution is a serious and widespread environmental problem that destroys microbial ecology. In this study, determination of copper and cadmium concentrations and heavy metal-resistant bacteria identification in water