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Could biotransport be an important pathway in the transfer of phenol derivatives into the coastal zone and aquatic system of the Southern Baltic? Full text
2020
Staniszewska, Marta | Nehring, Iga | Falkowska, Lucyna | Bodziach, Karina
Bird guano and the faeces of marine mammals appear to be a significant yet undisclosed biotransporter of Endocrine Disrupting Compounds in the marine environment. The authors determined the concentration of bisphenol A (BPA), 4-tert-octylphenol (4-t-OP) and 4-nonylphenol (4-NP) removed from birds and seals in their droppings into the coastal zone of the Gulf of Gdansk (Southern Baltic Sea).The research was carried out on samples of bird guano collected during the breeding season and after in 2016 at nesting sites, as well as on faecal samples from grey seals (Halichoerus grypus grypus) living in the Seal Centre of the Marine Station in Hel between 2014 and 2018. Measurements were carried out using high performance chromatography with fluorescence detector. Results have shown that the presence of seabird habitats and grey seal colonies in the coastal zone of the Gulf of Gdansk can have an impact on the pollution of the seashore (beach sand, bottom sediment and surface seawater) with phenol derivatives. The concentrations of BPA, 4-t-OP and 4-NP ranged from 0.1 to 32.97 ng∙g⁻¹dw in sediment and beach sand, and from 0.23 to over 800 ng dm⁻³ in seawater. In the cases of bisphenol A and 4-tert-octylphenol safe concentration levels in the waters were exceeded. Bisphenol A concentrations were almost always found to be the highest. This was also noted in bird guano and seal faeces, although it was found to be much higher in the seal faeces - average 10149.79 ng g⁻¹ dw, than in bird guano. An experiment conducted to assess BPA, 4-t-OP, 4-NP leaching from bird guano and seal faeces into seawater, also confirmed the importance of animal excrement in the circulation of these compounds in the marine ecosystem. The highest % of leaching related to BPA was noted at 20 °C and reached 84%. The lowest % of leaching was for 4-nonylphenol (44%).
Show more [+] Less [-]Does microplastic ingestion by zooplankton affect predator-prey interactions? An experimental study on larviphagy Full text
2020
Van Colen, Carl | Vanhove, Brecht | Diem, Anna | Moens, Tom
Litter is omnipresent in the ocean where it can be ingested by marine biota. Although ingestion of microplastics (MPs) is abundantly reported, insights into how MP can influence predator-prey interactions currently limits our understanding of the ecological impact of MPs. Here we demonstrate trophic transfer of MPs from zooplankton to benthic filter feeders, through consumption of contaminated prey (i.e. prey with ingested MP). However, predation rates of contaminated prey were significantly lower as compared to predation rates of prey that had no MPs ingested. As filter feeder clearance rates were not affected by consumption of MPs, the lower predation rates of contaminated prey appear to be primarily explained by disruption in zooplankton swimming behaviour that reduces their filtration risk. This is the first study that shows how MPs can change predator-prey interactions that are involved in the coupling between the pelagic and seabed habitat.
Show more [+] Less [-]Quasi-ultrafine particles promote cell metastasis via HMGB1-mediated cancer cell adhesion Full text
2020
Gao, Rui | Sang, Nan
With increasingly severe air pollution, the aggravated health risks of particulate matter, especially ultrafine particles, are emerging as an urgent and sensitive topic. Considering the heterogeneity and complexity of ultrafine particles, there is insufficient evidence about their toxic effects and possible molecular mechanisms. To address this question, we analyzed the emission characteristics of quasi-ultrafine particles collected during winter in a typical coal-burning city, Taiyuan, and confirmed their contribution to lung cancer cell adhesion and metastasis. For the specific mechanism, we revealed that the endocytosis of quasi-ultrafine particles stimulated the release of HMGB1, induced NFκB-facilitated proinflammatory cytokine production through the interaction of HMGB1 with RAGE, and resulted in cancer-endothelial cell adhesion. These findings remind us of the potential effects of anthropogenic quasi-ultrafine particle pollution and provide a theoretical reference for the mitigation of tumorigenesis in a severe particulate matter contaminated environment.
Show more [+] Less [-]Effects of nano-zerovalent iron on antibiotic resistance genes and mobile genetic elements during swine manure composting Full text
2020
Wang, Qianzhi | Gu, Jie | Wang, Xiaojuan | Ma, Jiyue | Hu, Ding | Peng, Huiling | Bao, Jianfeng | Zhang, Ranran
Livestock manure is a reservoir for antibiotic resistance genes (ARGs), and aerobic composting is used widely for recycling animal manure. This study investigated the effects of adding nano-zerovalent iron (nZVI) at 0, 100, and 1000 mg/kg on the fates of ARGs and mobile genetic elements (MGEs) during swine manure composting. Under nZVI at 100 mg/kg, the relative abundances of sul1, sul2, dfrA7, ermF, and ermX decreased by 33.26–99.31% after composting, and the relative abundances of intI2 and Tn916/1545 decreased by 95.59% and 97.65%, respectively. Most of the ARGs and MGEs co-occurred and they had strong correlations with each other. The bacterial community structure was significantly separated by the composting periods, and they clustered together under different treatments in the same phase. Network analysis showed that Solibacillus, Clostridium_sensu_stricto_1, Terrisporobacter, Romboutsia, Turicibacter, Lactobacillus, Planococcus, Dietzia, and Corynebacterium_1 were common potential hosts of ARGs and MGEs. Redundancy analysis suggested that MGEs had key effects on the variations in the relative abundances of ARGs. Adding 100 mg/kg nZVI could reduce the environmental risk of ARGs by decreasing the abundances of MGEs.
Show more [+] Less [-]Children exposure to inorganic and organic arsenic metabolites: A cohort study in Northeast Italy Full text
2020
Bocca, Beatrice | Pino, Anna | Brumatti, Liza Vecchi | Rosolen, Valentina | Ronfani, Luca | D’Aversa, Jenny | Ruggieri, Flavia | Petrucci, Francesco | Calamandrei, Gemma | Barbone, Fabio | Alimonti, Alessandro
The aim of this study was to provide urinary levels of total arsenic (TAs) and As species as arsenobetaine (AsB), arsenocholine (AsC), inorganic As (i.e., [As(III)+As(V)]), methylarsonic acid (MMA) and dimethylarsinic acid (DMA) in 7 year-old-children (n = 200) enrolled in the Northern Adriatic Cohort II (NACII), a prospective cohort in a coastal area of Northeast Italy. TAs was determined by sector field-inductively coupled plasma mass spectrometry (SF-ICP-MS) and AsB, AsC, As(III), As(V), MMA and DMA by ion chromatography coupled to ICP-MS (IC-ICP-MS). The geometric mean (GM) for TAs was 12.9 μg/L and for [iAs + MMA + DMA] was 4.26 μg/L. The species AsB (GM of 5.09 μg/L) and DMA (GM of 3.20 μg/L) had the greatest percentage contribution to TAs levels; a greater percentage contribution from AsB is seen at TAs >10 μg/L and from DMA at TAs <10 μg/L. Urinary [iAs + MMA] levels were positively associated with [iAs + MMA + DMA] and DMA with AsB levels. Fish, shellfish and crustaceans consumption increased the AsB and TAs levels, while rice intake, mothers’ education level and selenium (Se) concentration influenced the DMA concentration. Children have a high capacity to metabolize and detoxify the iAs because of the higher secondary methylation index (ratio DMA/MMA) with respect to primary methylation index (ratio MMA/iAs). In addition, the median level of [iAs + MMA + DMA] in the whole population of children was lower than the Biomonitoring Equivalent (BE) value for non-cancer endpoints. Also the Margin of Safety (MOS) value based on the population median was greater than 1, thus the exposure to the toxicologically relevant As species was not likely to be of concern.
Show more [+] Less [-]Effects of climate warming and nitrogen deposition on subtropical montane ponds (central China) over the last two centuries: Evidence from subfossil chironomids Full text
2020
Zheng, Ting | Cao, Yanmin | Peng, Jia | Bai, Xue | Chen, Xu
Many remote montane ecosystems are experiencing biogeochemical changes driven by warming climate and atmospheric pollution. Compared with circumpolar and temperate lakes, the responses of subtropical montane lakes to these external stressors have been less investigated. Here we present sedimentary multi-proxies records (i.e. chironomids, elements and stable isotope of carbon and nitrogen) in ²¹⁰Pb-dated cores from two montane ponds (central China). Before the 1900s, low biomass and the dominance of opportunistic species (e.g. Chironomus anthracinus-type) in both ponds might be in response to cold and harsh condition. Thereafter, chironomid communities in both ponds experienced pronounced shifts. Nutrient-tolerant/warm-adapted species (e.g. Chironomus sp., Polypedilum nubeculosum-type and Endochironomus impar-type) proliferated and biomass increased synchronously after the 1900s, suggestive of favorable condition for chironomid growth. Redundancy analyses revealed that changes in chironomid communities in both ponds were significantly correlated with rising temperature and δ¹⁵N depletion. Prolonged growing season and nitrogen subsidy would increase primary productivity, and hence enhancing food availability for chironomids. Catchment-mediated indirect effects of warming and nitrogen deposition, such as hydrological changes and terrestrial organic matter inputs, would impose further influences on chironomid communities. Taken together, the combined effects of climate warming and nitrogen deposition have caused significant shifts in primary consumers of these montane ponds, and imposed cascading effects on structure and function of subtropical montane aquatic ecosystems.
Show more [+] Less [-]An ICT-based fluorescent probe with a large Stokes shift for measuring hydrazine in biological and water samples Full text
2020
Zhu, Meiqing | Xu, Yimin | Sang, Linfeng | Zhao, Zongyuan | Wang, Lijun | Wu, Xiaoqin | Fan, Fugang | Wang, Yi | Li, Hui
As a strong reductant and highly active alkali, hydrazine (N2H4) has been widely used in chemical industry, pharmaceutical manufacturing and agricultural production. However, its high acute toxicity poses a threat to ecosystem and human health. In the present study, a ratiometric fluorescent probe for the detection of N2H4 was designed, utilizing dicyanoisophorone as the fluorescent group and 4-bromobutyryl moiety as the recognition site. 4-(2-(3-(dicyanomethylene)-5,5-dimethylcyclohex-1-enyl) phenyl 4-brobutanoate (DDPB) was readily synthesized and could specially sense N2H4 via an intramolecular charge transfer (ICT) pathway. The cyclization cleavage reaction of N2H4 with a 4-bromobutyryl group released phenolic hydroxyl group and reversed the ICT process between hydroxy group and fluorophore, turning on the fluorescence in the DDPB-N2H4 complexes. DDPB exhibits a low cytotoxicity, reasonable cell permeability, a large Stokes shift (186 nm) and a low detection limit (86.3 nM). The quantitative determination of environmental water systems and the visualization fluorescence of DDPB test strips provides a strong evidence for the applications of DDPB. In addition, DDPB is suitable for the fluorescence imaging of exogenous N2H4 in HeLa cells and zebrafish.
Show more [+] Less [-]Polybrominated diphenyl ethers and organochloride pesticides in the organic matter of air suspended particles in Mexico valley: A diagnostic to evaluate public policies Full text
2020
Beristain-Montiel, E. | Villalobos-Pietrini, R. | Nuñez-Vilchis, A. | Arias-Loaiza, G.E. | Hernández-Paniagua, I.Y. | Amador-Muñoz, O.
The presence of organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs) was analysed in air particulate matter ≤ 2.5 μm (PM₂.₅) and ≤10 μm (PM₁₀) collected in the Metropolitan Zone of Mexico Valley (MZMV), during 2013 and 2014, respectively. Spatial and seasonal distributions of PM and their organic content named solvent extracted organic matter (SEOM) were determined. PM mass concentration and SEOM/PM ratios were compared with previous studies in 2006 in Mexico City. PM₂.₅ concentration was like found in 2006, however, PM₁₀ decreased ∼43%. The SEOM/PM₁₀ ratio was kept constant, suggesting a decrease in SEOM as well as PM₁₀ emitted from natural sources, probably as a result of changes in the land use due to urban growth. A decrease ∼50% SEOM/PM₂.₅ ratio was observed in the same period, linked to adequate strategies and public policies applied by the local and federal governments to control the organic matter emitted from anthropogenic sources.Seven out of sixteen OCPs and five out of six PBDEs were found. The most common POPs were endosulfan I, endosulfan II, endosulfan sulfate, BDE-47 and BDE-99, present on >90% of the sampling days. OCPs in PM₂.₅ and PBDEs in PM₁₀ showed seasonal variability. Higher PBDEs concentration in both particle sizes were observed at east and southeast of the MZMV, where one of the biggest landfills and wastewater treatment plants are located. OCPs in PM₁₀ were mainly emitted from agricultural areas located to the southwest, southeast and east of the MZMV. OCPs in PM₂.₅ showed a regional contribution from the north and introduced into the valley. OCP degradation products were dominant over native OCPs, indicating no fresh OCP use. POPs comparison with other cities was made. Agreements and commissions created by the Mexican government reduced OCPs emissions, however, more effort must be made to control PBDE emission sources.
Show more [+] Less [-]Accumulation of metal-based nanoparticles in marine bivalve mollusks from offshore aquaculture as detected by single particle ICP-MS Full text
2020
Xu, Lina | Wang, Zhenyu | Zhao, Jian | Lin, Meiqi | Xing, Baoshan
The exposure risk of metal-based nanoparticles (NPs) to marine organisms and related food safety have attracted increasing attention, but the actual concentrations of these NPs in seawater and marine organisms are unknown. In this work, single particle inductively coupled plasma-mass spectrometry (spICP-MS) was used to quantify the concentrations and size distributions of NPs in different marine mollusks (oysters, mussels, scallops, clams, and ark shells) from an offshore aquaculture farm. Results showed that Ti, Cu, Zn, and Ag bearing NPs were detected in all the five mollusks with the mean sizes at 65.4–70.9, 72.2–89.6, 97.8–108.3, and 42.9–51.0 nm, respectively. The particle concentrations of Ti, Cu, Zn, and Ag bearing NPs in all mollusks (0.88–3.26 × 10⁷ particles/g fresh weight) were much higher than that in the seawater (0.46–0.79 × 10⁷ particles/mL), suggesting bio-accumulation of NPs. For all the five mollusks, Ag bearing NPs had the highest number-based bioconcentration factors (NBCFs) in all the tested NPs due to the smallest mean size of Ag bearing NPs in seawater (30.5 nm). In addition, the clams exhibited the lowest NBCFs of the four NPs than other mollusks. All four NPs were mainly accumulated in the gill and digestive gland, and could transfer to adductor muscle of all mollusks. Although all the four metals (Ti, Cu, Zn, Ag) in mollusks were safe for human consumption by the estimated daily intake (EDI) analysis, the risk of NPs remaining in the mollusks should be further considered when evaluating the toxicity of metals for human health. The findings could improve our understanding on the distribution and health risk of NPs in marine mollusks under offshore aquaculture.
Show more [+] Less [-]Ecotoxicity of three plant-based biodiesels and diesel using, Eisenia fetida Full text
2020
Bamgbose, Ifeoluwa A. | Anderson, Todd A.
Soil pollution is growing at an alarming rate in today’s industrialized world as a result of increasing anthropogenic activities, either intentional (e.g., use of fertilizers and pesticides, irrigation with untreated wastewater, or land application of sewage sludge) or accidental (e.g., oil spills or leaching from landfills). Terrestrial soil pollution from transportation fuels such as Diesel or Biodiesel is inevitable as they are part of life’s necessities. Biodiesel is considered an environmental friendly fuel due to its non-hydrocarbon composition and low particulate matter emission. However, there are still some controversies regarding biodiesel environmental toxicity to terrestrial life. Little is known about the ecotoxicity of plant-based biodiesels to soil organisms. In the present study, three ecotoxicological tests including an earthworm (Eisenia fetida) 14-day soil toxicity test, a filter paper contact toxicity test, and a cocoon hatchability test were performed to examine the toxic effects of three plant-based biodiesels - safflower methyl ester (SaME), castor methyl ester (CME), and castor ethyl ester (CEE), with Diesel fuel. Unlike Diesel, the biodiesels were less toxic based on low earthworm mortality in the soil toxicity test. However significant morbidity responses (e.g., weight loss, coiling, posterior and anterior fragmentation, and excessive discharge of coelomic fluid) were observed in earthworms exposed to biodiesel. Further, in the cocoon hatchability test, biodiesels were equally toxic to Diesel at 2% and 5% soil concentrations, with no hatching success.
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