This study assesses for the first time the concentrations of microplastics (MPs) in sediments, water and two human-consumed mussels with different ecological traits (Amarilladesma mactroides and ...Brachidontes rodriguezii) in a touristic sandy beach of Argentina. MPs were characterized through FTIR and SEM/EDX techniques. All the samples presented MPs with similar concentrations as other human-impacted coastal areas of the world, being black and blue fibers of < 0.5 and 0.5-1 mm the most abundant. SEM images exhibited cracks and fractures with clay minerals and microorganisms adhered to MPs surface. EDX spectrums showed potentially toxic elements, such as Cr, Ti, and Mo. FTIR identified polymers such as cellulose, polyamides, and polyacrylates in most of the samples analyzed. Our study demonstrates that microplastic pollution is a common threat to sandy beaches in Argentina, worsened by plastic particles carrying metal ions with potential toxic effects to the biota, including A. mactroides, an endangered species.
•Meso/microplastics were found in waters, sediments, and bivalves in Argentina.•Microplastics ranged from 0.15–0.5 item g ww-1 in mussels.•Cr, Mo, Ti, Al, and Fe were detected on the surface of fibers.•The most abundant microplastics were cellulose, polyamides, and polyacrylates.
Microplastics have been a global concern due to their potential and widespread risks to organisms and environments. In this study, we investigated the abundance, distribution, and characteristics of ...microplastics (MPs) in the surface waters of the Bahía Blanca Estuary (BBE), specifically in its inner and middle zone. The results showed the dominant shape of MPs were fibers, being black, transparent, and blue the main colors. The concentrations of MPs ranged from 182 to 33,373 items m–3 with a mean value of 6162 items m–3. The highest concentrations of MPs were detected in the middle zone of the estuary, a site that receives untreated sewage effluents from the city. The most abundant size ranges were from 0.5 to 1.5 mm (44.21%) and ˂0.5 mm (40.21%) and were predominant at all the sampling sites. The concentration of mesoplastics in the inner zone (16 items m–3) presented larger values than in the middle zone (5 items m–3). A wide variety of polymeric materials with predominance of microfibers such as cellulose-based, polyacrylonitrile, polyethylene terephthalate, and polypropylene were identified. Polyester/alkyd resins and poli(vinyl chloride) were also found. The analysis of MPs surface through SEM/EDX detected a variety of elements such as C, O, Si, Al, K, Ca, Cl, Ti, Fe, S, and P, indicating potential contaminant carriers in the water column. Some plastic particles presented a high degree of degradation on their surface morphology. Untreated sewage discharges appear to be a significant input of MPs. Therefore, the results provided in the present study should be considered by stakeholders interested in the management and conservation of this large coastal wetland with significant ecological and economic value.
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•A mean of 6162 items m-3 was found in the surface waters of the estuary.•Cellulose, polyacrylonitrile, and polyesters were the most common polymers.•Mesoplastics (˃5 mm) were more abundant in the inner part of the estuary.•Black and transparent microplastics were the most conspicuous.•Sewage waters seemed to be the main input source of microplastics pollution.
Marine microdebris (MDs, <5 mm) and mesodebris (MesDs, 5–25 mm), consist of various components, including microplastics (MPs), antifouling or anticorrosive paint particles (APPs), and metallic ...particles (Mmps), among others. The accumulation of these anthropogenic particles in macroalgae could have significant implications within coastal ecosystems because of the role of macroalgae as primary producers and their subsequent transfer within the trophic chain. Therefore, the objectives of this study were to determine the abundance of MDs and MesDs pollution in different species of macroalgae (P. morrowii, C. rubrum, Ulva spp., and B. minima) and in surface waters from the Southwest Atlantic coast of Argentina to evaluate the ecological damage. MDs and MesDs were chemically characterized using μ-FTIR and SEM/EDX to identify, and assess their environmental impact based on their composition and degree of pollution by MPs, calculating the Polymer Hazard Index (PHI). The prevalence of MDs was higher in foliose species, followed by filamentous and tubular ones, ranging from 0 to 1.22 items/g w.w. for MPs and 0 to 0.85 items/g w.w. for APPs. It was found that macroalgae accumulate a higher proportion of high-density polymers like PAN and PES, as well as APPs based on alkyd, PMMA, and PE resins, whereas a predominance of CE was observed in surrounding waters. Potentially toxic elements, such as Cr, Cu, and Ti, were detected in APPs and MPs, along with the presence of epiplastic communities on the surface of APPs. According to PHI, the presence of high hazard score polymers, such as PAN and PA, increased the overall risk of MP pollution in macroalgae compared to surrounding waters. This study provided a baseline for MDs and MesDs abundance in macroalgae as well as understanding the environmental impact of this debris and their bioaccumulation in the primary link of the coastal trophic chain.
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•Macroalgae accumulate microplastics, paint flakes, and metallic microparticles.•U. rigida tends to accumulate larger amounts of macrodebris than other algae species.•Marine microdebris containing additives based on Ba, Cr, Fe, Cu, and Ti were detected.•Significant number of high-density microplastic fibers were found in macroalgae.•The Polymer Hazard Index considers a high risk of microplastics in macroalgae exists.
Microplastics (MPs) and antifouling paint particles (APPs) are important components of marine microdebris (MDs), which constitute a potential environmental risk. This study analyzed baseline ...contamination levels of MDs and mesodebris (MesDs) in intertidal sediments at different depths, exploring the geomorphological influence in three Argentine coastal environments: Bahía Blanca Estuary (BBE), Los Pocitos (LP) and Puerto Madryn (PM). The MDs and MesDs samples were characterized by μ-FTIR, SEM/EDX and XRD. The abundance of MPs and APPs in sediments, range between 19.78 and 1087.19 and between 0 and 172.93 items/kg d.w., respectively. Despite variations in population and industrial developments in these areas, MPs abundance shows no significant differences in low and high intertidal zones. However, mean MPs concentrations were higher in the surface layer (0–5 cm) compared to the deeper sediments (5–10 cm), indicating recent MPs deposition. Chemical characterization evidenced the presence of cellulose (CE) and denser polymers as acrylonitrile butadiene styrene (ABS) and polyacrylics (PAN), APPs, metallic and black MDs. Surface degradation and heavy metals (Zn, Cr, and Ba) were also detected in APPs and other MDs, either as additives or adhered to their surfaces. Changes in crystallinity were also observed on the MesDs due to weathering. The calculated polymer hazard index (PHI) and the presence of hazardous polymers such as ABS and PAN indicated an increased risk of MPs pollution on the BBE and PM coasts. The pollution load index (PLI) values (from 4.63 to 5.34) suggested unpolluted to moderately polluted levels. These findings offer insights into potential risks associated with MDs in Argentine intertidal sediments, underscoring the critical need to comprehend the geomorphology and the influence of coastal dynamics. This is crucial for effectively addressing challenges linked to MDs pollution guiding the development of robust management and mitigation strategies.
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•Ti, Fe, Mo, Zn, Cr, and Ba were detected in APPs and microdebris fragments.•PET, ABS, PVA, PTFE, and PAN microplastics, as well as APPs, were identified in sediment.•The abundance of microdebris in coastal environments is influenced by the geomorphology and hydrodynamic conditions.•Based on PHI values, beach sediments of BBE and PM had a high level of chemical risk.•Coastal sediment particle sizes do not tend to enhance the accumulation of MPs.
The composition and the interaction of the suspended particulate matter (SPM) with metal ions, along with the presence and characteristics of microplastics, were analyzed for the first time in the ...water column of the inner zone of Bahía Blanca Estuary during winter (June, July, and August) 2019. Surface analysis techniques (Scanning Electron Microscopy combined with Energy Dispersive X-ray Spectroscopy, X-ray Photoelectron Spectroscopy, and X-ray Diffraction) were employed to obtain an in-depth characterization of the particulate matter, suggesting the presence of Fe in our samples, with a mixture of Fe3+/Fe2+ oxidation states. Microplastics ranged in concentrations between 3 and 11.5 items L−1, with an average of 6.50 items L−1 (S.E: ±4.01), being fibers the most abundant type. Infrared Spectroscopy suggests that these fibers correspond to semi-synthetic cellulose-based and poly(amide) remains. We concluded that the SPM is a significant vehicle for metals which might have adverse effects on marine organisms.
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•First detailed assessment of suspended particulate matter (SPM) and microplastics (MPs) in the Bahía Blanca Estuary.•Metal-phosphates bonds and mixtures of Fe3+/Fe2+ were detected in the SPM.•MPs abundance ranged 3 to 11.5 items.L-1•MPs were mostly represented by semi-synthetic cellulose fibers and poly(amide)•SPM and MPs as the main transport vectors for metals in the Bahía Blanca Estuary.
Total ozone relationships with selected upper troposphere/lower stratosphere variables (400‐ and 70‐hPa temperatures, tropopause height and temperature, 70‐hPa geopotential height, and 340‐K ...potential vorticity), as well as between the variables, are analyzed on decadal scales over Southern Hemisphere midlatitudes for the period 1980–2000. Total Ozone Mapping Spectrometer version 8 total ozone and European Centre for Medium Range Weather Forecast ERA‐40 data products for June and October (early winter and spring) are used. Multiple spatial correlation techniques and shared variance estimates are applied to infer relationships between mean fields as well as among decadal difference fields. Wave activity Z and local Eliassen‐Palm fluxes were calculated to further analyze the dynamics of the samples and their variability. The statistical studies show that observed total ozone latitudinal and longitudinal decadal variations can be driven by upper tropospheric and stratospheric variability, depending on latitude and season. The sampled regions, divided into subtropical and subpolar, yield differentiated relationships. October ozone decadal variations during the 1980s, particularly at higher latitudes, are attributed primarily to chemical ozone depletion, while there appear to be links between tropospheric decadal change and some of the stratospheric variables and tropopause behavior. In the 1990s, tropospheric contributions decrease, and stratospheric quasi stationary wave 1 plays a major role. In June, tropospheric change/variability appears to be more important than stratospheric driving, which nevertheless also contributes to change. Ozone change in the 1990s responded more to stratospheric dynamic change at higher latitudes, but despite reduced contributions, the troposphere remains a driver of variation at the lower latitudes of the sample.
The variability of atmospheric midlatitudinal ozone between 1980 and 2000 over the Southern Hemisphere is discussed. The distribution of ozone and ozone change during the seasonal cycle is discussed ...using Total Ozone Mapping Spectrometer Nimbus and Earth Probe data binned at 72 (30° longitude by 5° latitude) bins, between 60° and 30°S. Rather than using a standard trend approach, the annual mean time series for each bin were fitted with a cubic polynomial. The results show that in the zonal mean sense there is a sizable, latitude‐dependent slowdown of the ozone loss from the early 1990s onward, but when individual bins are considered, significant longitudinal patterns of ozone change appear, with both positive (enhancement) and negative (depletion) changes in total ozone. Thus regional evolution remains important as an indicator both of chemical depletion evolution and the relation with climate. Such longitudinal behavior is limited in the subtropics and grows toward the subpolar edge of the sampled region. For example, a large decrease was observed over southern South America in the 1980s, but during the 1990s there was only a limited change. The analysis for January, June, and October over the 20‐year period shows changes in the evolution along the year, both in time and space. Furthermore, such seasonally dependent changes reach a peak in October, as would be expected. The October pattern of interannual variability could be linked to Southern Annular Mode, though there probably are some other processes driving it.
The synthesis of CF3OC(O)OOCF3, CF3OC(O)OOC(O)OCF3, and CF3OC(O)OOOC(O)OCF3 is accomplished by the photolysis of a mixture of (CF3CO)2O, CO, and O2. Pure CF3OC(O)OOCF3 and CF3OC(O)OOC(O)OCF3 are ...isolated after thermal decomposition of CF3OC(O)OOOC(O)OCF3 and repeated trap-to-trap condensation. Additional spectroscopic data of known CF3OC(O)OOCF3 are obtained by recording NMR, IR, Raman, and UV spectra. At room temperature CF3OC(O)OOC(O)OCF3 is stable for days in the liquid or gaseous state. The melting point is −38 °C, and the boiling point is extrapolated to 73 °C from the vapor pressure curve log p = 8.657 − 1958/T (p/mbar, T/K). The new compound is characterized by molecular mass determination and by NMR, vibrational, and UV spectroscopy. The new trioxide CF3OC(O)OOOC(O)OCF3 cannot be separated from CF3OC(O)OOC(O)OCF3 by distillation due to their similar boiling points. CF3OC(O)OOOC(O)OCF3 decomposes at room temperature within hours into a mixture of CF3OC(O)OOC(O)OCF3, CF3OC(O)OOCF3, CO2, and O2. Its characterization is discussed along with a possible mechanism for formation and decomposition reactions.
The ultraviolet absorption spectrum of gas phase CF
3OONO
2 has been measured over the wavelength range 200–340
nm at 233–300
K. Absorption cross-sections at wavelengths of 290–340
nm were found to ...increase significantly with increasing temperature. The UV spectra of CF
3C(O)Cl and CF
3C(O)F were measured and were consistent with previous work Rattigan et al., 1993. Temperature-dependent absorption cross-sections of CF
3COCl, CF
3COF, CH
3COF, CCl
3CHO and CF
3COOH. Journal of Photochemistry and Photobiology A: Chemistry 73, 1–9. Implications for the atmospheric chemistry of CF
3OONO
2 are discussed.
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