scholarly journals Environmental hazard of polypropylene microplastics from disposable medical masks: acute toxicity towards Daphnia magna and current knowledge on other polypropylene microplastics

2022 ◽  
Vol 2 (1) ◽  
Author(s):  
Anita Jemec Kokalj ◽  
Andraž Dolar ◽  
Damjana Drobne ◽  
Marjan Marinšek ◽  
Matej Dolenec ◽  
...  

AbstractThe COVID-19 pandemic has increased the use of disposable plastics, including medical masks, which have become a necessity in our daily lives. As these are often improperly disposed of, they represent an important potential source of microplastics in the environment. We prepared microplastics from polypropylene medical masks and characterised their size, shape, organic chemical leaching, and acute toxicity to the planktonic crustacean Daphnia magna. The three layers of the masks were separately milled and characterised. Each of the inner frontal, middle filtering, and outer layers yielded different types of microplastics: fibres were obtained from the inner and outer layer, but irregular fragments from the middle layer. The shape of the obtained microplastics differed from the initial fibrous structure of the intact medical mask layers, which indicates that the material is deformed during cryo-milling. The chemical compositions of plastics-associated chemicals also varied between the different layers. Typically, the inner layer contained more chemicals related to antimicrobial function and flavouring. The other two layers also contained antioxidants and their degradation products, plasticisers, cross-linking agents, antistatic agents, lubricants, and non-ionic surfactants. An acute study with D. magna showed that these microplastics do not cause immobility but do physically interact with the daphnids. Further long-term studies with these microplastics are needed using a suite of test organisms. Indeed, studies with other polypropylene microplastics have shown numerous adverse effects on other organisms at concentrations that have already been reported in the environment. Further efforts should be made to investigate the environmental hazards of polypropylene microplastics from medical masks and how to handle this new source of environmental burden.

2022 ◽  
Vol 45 ◽  
pp. 102485
Author(s):  
Carlos Eduardo Lach ◽  
Camila Schwarz Pauli ◽  
Aline Scheller Coan ◽  
Edesio Luiz Simionatto ◽  
Luciano André Deitos Koslowski

2014 ◽  
Vol 26 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Raquel Aparecida Moreira ◽  
Adrislaine da Silva Mansano ◽  
Lidiane Cristina da Silva ◽  
Odete Rocha

AIM: In this study we compared the sensitivity of three species of Cladocera, Daphnia magna, Ceriodaphnia silvestrii and Macrothrix flabelligera, to the commercial product of the herbicide Atrazine, the Atrazine Atanor 50 SC® (500 g/L), widely used on crops in Brazil. METHODS: Acute toxicity tests were performed at the nominal atrazine concentrations 2.25, 4.5, 9.0, 18.0, 36 and 72 mg L-1, on C. silvestrii and M. flabelligera and at 2.25, 4.5, 9.0, 18.0, 36, 72 and 144 mg L-1 on D. magna. The range of concentrations tested was established in a series of preliminary tests. RESULTS: The toxicity tests showed that the two species naturally occurring in water bodies in Brazil were more susceptible than Daphnia magna. The effective concentrations of Atrazine Atanor 50 SC® (EC50- 48 h) to the species M. flabelligera, C. silvestrii and D. magna were 12.37 ± 2.67 mg L-1, 14.30 ± 1.55 mg L-1 and 50.41 ± 2.64 mg L-1, respectively. Furthermore, when EC50 observed here for M. flabelligera and C. silvestrii were compared with published values of EC50 or LC50 (mg L-1) for various aquatic organisms exposed to atrazine, it was seen that these two cladocerans were the most sensitive to the herbicide. CONCLUSIONS: Considering these results and the broad distribution of C. silvestrii and M. flabelligera in tropical and subtropical regions, it is concluded that these native species would be valuable test organisms in ecotoxicological tests, for the monitoring of toxic substances in tropical freshwaters.


2008 ◽  
Vol 58 (9) ◽  
pp. 1803-1812 ◽  
Author(s):  
M. N. Abellán ◽  
W. Gebhardt ◽  
H. Fr. Schröder

The ozonation of the antibiotic sulfamethoxazole has been studied, in order to elucidate the structures of some of the degradation products generated throughout the process. Under the conditions applied, a complete destruction of sulfamethoxazole was achieved after 10 minutes of reaction. The biodegradability of the resulting solution has been also determined, and this parameter undergoes a gradual increase along during the reaction time. The acute toxicity of the reaction mixture, on the contrary, is only decreased during the first 5 minutes of reaction while it increases subsequently. Some of the intermediates resulting during ozonation seem to be more toxic to Daphnia magna than the untreated sulfamethoxazole. The structures of selected degradation products found in the solution are determined and identified. Ozone predominantly attacks sulfamethoxazole via the amine group of the aniline ring in some cases giving rise to nitro-aromatic compounds.


1977 ◽  
Vol 12 (1) ◽  
pp. 27-50 ◽  
Author(s):  
L.A. Behie ◽  
J.E. Zajic ◽  
D. Berk ◽  
R.J.P. Brouzes ◽  
V.A. Naish

Abstract Although Daphnia magna have been widely used in the determination of the toxicity of various substances, there are no reports in the literature that describe a rigorous bioassay method using this organism as a test species. The test described herein involves the standariza-tion of various important aspects of the method such as the age of the test organisms, and the dilution water used for the preparation of the various toxicant concentrations. Also described is a simple method for the statistical analysis of the results. The sensitivity of the proposed bioassay is demonstrated by determining the toxicity of various pulp and paper effluents. Finally, extensive bioassays were carried out simultaneously with rainbow trout and Daphnia magna indicating that Daphnia are as good a biological indicator of acute toxicity as fish.


1990 ◽  
Vol 22 (5) ◽  
pp. 241-246 ◽  
Author(s):  
I. Brković-Popović

The median lethal time (LT) for each concentration of mercury was determined on the basis of mortality curves. Toxicity curves (i.e., the median life-span of Daphniamagna, LT 50, versus the concentration of mercury) for four tested conditions are shown. The experiments were carried out using two diluents of different total hardness (46 and 119 mg/l as CaCO3), at two temperatures (20°C and 25°C). A comparison of the LT 50s of the control organisms with the LT 50s of the test organisms at mercury concentrations of 0.0075 and 0.0050 mg. l-1 showed that the chemical characteristics and temperatures of the mediums tested did not affect the range of the ‘no effect' concentration. However, the incipient LC 50, and the time required for its appearance, did depend on the combination of the abiotic factors tested.


2011 ◽  
Vol 103 (1-2) ◽  
pp. 38-45 ◽  
Author(s):  
Roman Ashauer ◽  
Anita Hintermeister ◽  
Eva Potthoff ◽  
Beate I. Escher

2016 ◽  
Vol 258 ◽  
pp. S66
Author(s):  
O. Olaru ◽  
G. Nitulescu ◽  
C. Spinu ◽  
I. Potolea ◽  
O. Pirvu ◽  
...  

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Eun Kyung Sohn ◽  
Seyed Ali Johari ◽  
Tae Gyu Kim ◽  
Jin Kwon Kim ◽  
Ellen Kim ◽  
...  

To better understand the potential ecotoxicological impact of silver nanoparticles (AgNPs) and silver nanowires (AgNWs) released into freshwater environments, the toxicities of these nanomaterials were assessed and compared using Organization for Economic Cooperation and Development (OECD) test guidelines, including a “Daphniasp., acute immobilization test,” “Fish, acute toxicity test,” and “freshwater alga and cyanobacteria, growth inhibition test.” Based on the estimated median lethal/effective concentrations of AgNPs and AgNWs, the susceptibility to the nanomaterials was different among test organisms (daphnia > algae > fish), suggesting that the AgNPs are classified as “category acute 1” forDaphnia magna, “category acute 2” forOryzias latipes, and “category acute 1” forRaphidocelis subcapitata, while the AgNWs are classified as “category acute 1” forDaphnia magna, “category acute 2” forOryzias latipes, and “category acute 2” forRaphidocelis subcapitata, according to the GHS (Globally Harmonized System of Classification and Labelling of Chemicals). In conclusion, the present results suggest that more attention should be paid to prevent the accidental or intentional release of silver nanomaterials into freshwater aquatic environments.


2012 ◽  
Vol 161 ◽  
pp. 29
Author(s):  
Dilsad Onbasili ◽  
Fatih Duman ◽  
Berrak Altinsoy ◽  
Hatice Bekci

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