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Using the compound system to synthetically evaluate the enrichment of heavy metal(loid)s in a subtropical basin, China
2020
Zhang, Hua | Zeng, Huan | Jiang, Yinghui | Xie, Zhenglei | Xu, Xiaoling | Ding, Mingjun | Wang, Peng
A compound system involving three matrices (water, sediment, and paddy soil) was conceived to determine the potential sources of metal(loid)s (Ti, Fe, Co, Ni, Cu, Zn, As, Cd, Pb, and U) and synthetically evaluate their pollution levels in the Le’an River basin. The result indicated that the established background values (BVs) of paddy soil and sediment in the compound system were obviously higher than those of the upper continental crust (UCC) and soils from Jiangxi Province, a difference which was especially marked for sediment. The concentrations of Cu, Zn, As, Cd in the system had high coefficients of variation (CVs), and metal(loid)s in sediment showed higher levels than those in paddy soil, except for Pb. Cd and Cu in the system had the highest Ef levels, which probably pose a high risk to organisms and the health of local residents. There were significantly linear relationships between the site rank index (SRI) for water and that for sediment or paddy soil, revealing that matrices in the system interacted with each other. Principal component analysis (PCA) and absolute principal component scores and multiple linear regression model (APCS-MLR) results demonstrated that Cu, Zn, As, Cu, Pb, and U enrichments in the system were mainly affected by mining activities and were predominately deposited in sediment. Point pollution sources rather than non-point pollution sources such as mining activities, contributed most of the anthropogenic metal(loid)s to sediment. Both SRI and Hierarchical cluster analysis (HCA) results visually showed that S5, S8, S9, S10, S11, and S12 severe pollution grouped together and scattered through areas with extensive mining activities, while other sites with moderate pollution were spread along the main stream of the Le’an River.
Mostrar más [+] Menos [-]Compositional profiles, persistency and toxicity of polychlorinated naphthalene (PCN) congeners in edible cod liver products from 1972 to 2017
2020
Falandysz, Jerzy | Fernandes, Alwyn R.
Edible cod liver products including cod liver oil and canned cod liver, sampled over the last five decades from the North Atlantic region, including the Baltic Sea were analysed for a set of persistent and toxicologically significant polychlorinated naphthalene (PCN) congeners with some of the highest relative potencies (dioxin-like toxicity) among PCNs. The targeted congeners showed a near-universality of occurrence in all samples apart from the most recent sample of cod liver oil which was assumed to be highly purified, as cod livers from the same period and location showed appreciable amounts of PCNs. The majority of dominant congeners in legacy technical PCN mixtures were absent or occurred in low concentrations, raising the possibility that congeners arising from combustion related sources may be acquiring a greater significance following the decline and elimination of PCN production. The apparent appreciation in the relative amounts of PCN#70 in the last three to four decades may provide support for this view. The PCN contribution to dioxin-like toxic equivalence (TEQ) that was estimated for these samples (range 1.2–15.9 pg TEQ g⁻¹) was significant in comparison to the EU regulated value of 1.75 pg TEQ g⁻¹ for dioxins in fish oils. Most of the TEQ was associated with PCNs 66/67, 64/68, 69 and 73. Although metabolic processes are likely to influence this distribution, the profile is a little different to that observed in the tissues of higher order animals where PCNs #66/67 and #73 may contribute approximately 90% to the summed TEQ.
Mostrar más [+] Menos [-]Ambient particulate matter source apportionment using receptor modelling in European and Central Asia urban areas
2020
Almeida, S.M. | Manousakas, M. | Diapouli, E. | Kertesz, Z. | Samek, L. | Hristova, E. | Šega, K. | Alvarez, R Padilla | Belis, C.A. | Eleftheriadis, K.
This work presents the results of a PM2.5 source apportionment study conducted in urban background sites from 16 European and Asian countries. For some Eastern Europe and Central Asia cities this was the first time that quantitative information on pollution source contributions to ambient particulate matter (PM) has been performed. More than 2200 filters were sampled and analyzed by X-Ray Fluorescence (XRF), Particle-Induced X-Ray Emission (PIXE), and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to measure the concentrations of chemical elements in fine particles. Samples were also analyzed for the contents of black carbon, elemental carbon, organic carbon, and water-soluble ions. The Positive Matrix Factorization receptor model (EPA PMF 5.0) was used to characterize similarities and heterogeneities in PM2.5 sources and respective contributions in the cities that the number of collected samples exceeded 75. At the end source apportionment was performed in 11 out of the 16 participating cities. Nine major sources were identified to have contributed to PM2.5: biomass burning, secondary sulfates, traffic, fuel oil combustion, industry, coal combustion, soil, salt and “other sources”. From the averages of sources contributions, considering 11 cities 16% of PM2.5 was attributed to biomass burning, 15% to secondary sulfates, 13% to traffic, 12% to soil, 8.0% to fuel oil combustion, 5.5% to coal combustion, 1.9% to salt, 0.8% to industry emissions, 5.1% to “other sources” and 23% to unaccounted mass. Characteristic seasonal patterns were identified for each PM2.5 source. Biomass burning in all cities, coal combustion in Krakow/POL, and oil combustion in Belgrade/SRB and Banja Luka/BIH increased in Winter due to the impact of domestic heating, whereas in most cities secondary sulfates reached higher levels in Summer as a consequence of the enhanced photochemical activity. During high pollution days the largest sources of fine particles were biomass burning, traffic and secondary sulfates.
Mostrar más [+] Menos [-]Effects of biological factors and seasonality on the level of polycyclic aromatic hydrocarbons in red mullet (Mullus barbatus)
2020
Frapiccini, E. | Panfili, M. | Guicciardi, S. | Santojanni, A. | Marini, M. | Truzzi, C. | Annibaldi, A.
This study evaluates the effects of biological factors of fish and seasonality on Polycyclic Aromatic Hydrocarbon (PAH) accumulation in red mullet (Mullus barbatus) tissue. Specimens were collected monthly with a bottom trawl net in an offshore fishing ground in the Northern and Central Adriatic Sea (Geographical Sub Area 17) throughout 2016.The edible fillets of 380 individuals were analyzed for the concentrations of individual PAH, total PAH, and low, medium and high molecular weight (MW) PAHs. PAH bioaccumulation was related to their physicochemical characteristics (MW, and logarithm of the octanol-water partition coefficient, log Kₒw), some biological parameters of fish (body size, age, sex, reproductive stage and total lipid content), and catch season.The PAH bioaccumulation pattern and the effects of the different factors varied according to PAH MW. The heavier (medium and high MW) PAHs showed higher levels in winter-autumn and in pre-spawners compared with spawners and post-spawners. Our findings suggest that an important detoxification mechanism, albeit limited to the heavier PAHs, acts in the spawning and post-spawning stage. Low MW PAHs appeared to be unaffected by reproductive stage, lipid content and seasonality. Reproductive stage and seasonality seem to play an important role in the accumulation of heavier PAH, whereas total lipid content and age seem to exert a limited influence, and body size no effect at all.
Mostrar más [+] Menos [-]Airborne toluene exposure causes germline apoptosis and neuronal damage that promotes neurobehavioural changes in Caenorhabditis elegans
2020
Soares, Marcell Valandro | Charão, Mariele Feiffer | Jacques, Mauricio Tavares | dos Santos, Ana Laura Anibaletto | Luchese, Cristiane | Pinton, Simone | Ávila, Daiana Silva
Toluene is a highly volatile organic solvent present in gasoline. Exposure mainly occurs by absorption via the pulmonary tract and easily reaches the central nervous system, which causes toxic effects. Toluene toxicity has been described but not well established. The present work aimed to evaluate the effects of airborne exposure to toluene, the in vivo model Caenorhabditis elegans was assessed to determine whether nematode could be used to evaluate the effects of exposure to toluene and the possible mechanisms of toxicity of the solvent. Worms at the first or fourth larval stages were exposed to toluene for 48 or 24 h, respectively, in a laboratory-developed vapor chamber at concentrations of 450, 850, 1250 and 1800 ppm. We observed increases in worm mortality and significant developmental delays that occurred in a concentration-dependent manner. An increased incidence of apoptotic events in treated germline cells was shown, which was consistent with observed reductions in reproductive capacity. In addition, toluene promoted significant behavioural changes affecting swimming movements and radial locomotion, which were associated with changes in the fluorescence intensity and morphology of GABAergic and cholinergic neurons. We conclude that toluene exposure was toxic to C. elegans, with effects produced by the induction of apoptosis and neuronal damage.
Mostrar más [+] Menos [-]Trace element analysis reveals bioaccumulation in the squid Gonatus fabricii from polar regions of the Atlantic Ocean
2020
Lischka, A. | Lacoue-Labarthe, T. | Bustamante, P. | Piatkowski, U. | Hoving, H.J.T.
The boreoatlantic gonate squid (Gonatus fabricii) represents important prey for top predators—such as marine mammals, seabirds and fish—and is also an efficient predator of crustaceans and fish. Gonatus fabricii is the most abundant cephalopod in the northern Atlantic and Arctic Ocean but the trace element accumulation of this ecologically important species is unknown. In this study, trace element concentrations (Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, and Zn) were analysed from the mantle muscle and the digestive gland tissue of juveniles, adult females, and adult males that were captured south of Disko Island off West-Greenland. To assess the feeding habitat and trophic position of this species, stable isotopes of carbon (δ13C) and nitrogen (δ15N) were measured in their muscle tissue. Mercury concentrations were positively correlated with size (mantle length) and trophic position. The Hg/Se ratio was assessed because Se has been suggested to play a protective role against Hg toxicity and showed a molar surplus of Se relative to Hg. Cadmium concentrations in the digestive gland were negatively correlated with size and trophic position (δ15N), which suggested a dietary shift from Cd-rich crustaceans towards Cd-poor fish during ontogeny. This study provides trace element concentration data for G. fabricii from Greenlandic waters, which represents baseline data for a northern cephalopod species. Within West-Greenland waters, G. fabricii appears to be an important vector for the transfer of Cd in the Arctic pelagic food web.
Mostrar más [+] Menos [-]Development and validation of a UHPLC-MS/MS method for the identification of irinotecan photodegradation products in water samples
2020
Gosetti, Fabio | Belay, Masho Hilawie | Marengo, Emilio | Robotti, Elisa
Irinotecan (CPT-11) is a water-soluble anticancer drug widely used to treat several types of cancer.Even if the metabolites of CPT-11 are well-known and investigated, only limited information is available in the literature about the formation of photo-degradation products that can naturally originate from sunlight irradiation when the drug is released in aqueous systems.CTP-11 solutions at 10.0 mg L−1 were irradiated by simulated sunlight. The intensity of the drug decreased by 90% after 7.5 days of irradiation and no significant reduction of absorbance values was observed after 13 days.A sensitive UHPLC-MS/MS method was developed employing a hybrid triple quadrupole/linear ion trap mass spectrometer, that is able to work in data-dependent acquisition mode and to obtain information about the compounds formed during the photoirradiation. Moreover, a selected reaction monitoring method was built using the MS/MS fragmentation pattern of the compounds previously investigated. The method was validated considering LOD, LOQ, linearity, precision, selectivity, recovery and matrix effect. LOD and LOQ values were 0.02 and 0.05 ng mL−1, respectively, whereas MDL and MQL values in real water samples (river water, groundwater, well water, and wastewater) were lower than 0.05 and 0.2 ng mL−1, respectively.Eight photodegradation products were identified, among which five for the first time. Based on the MS and MS/MS fragmentation, the chemical structures of the degradation products were proposed. Hydrolysis experiments were carried out on the same solutions preserved in the dark, but no formation of other species was highlighted.The method was applied to several real samples: CPT-11 was detected and quantified only in a hospital effluent sample at the concentration of 0.41 ± 0.2 ng mL−1 together with the occurrence of PDP3.The outcomes of this study may be useful for updating the pollutant screening in water samples.
Mostrar más [+] Menos [-]Cadmium and kidney function: Concentrations, variabilities, and associations across various stages of glomerular function
2020
Jain, Ram B.
Data (N = 10336) from National Health and Nutrition Examination Survey for 2003–2016 for US adults aged ≥ 20 years were analyzed to evaluate the concentrations of blood and urine cadmium across the various stages of glomerular function. Estimated glomerular filtration rate (eGFR) > 90 mL/min/1.73 m2 was defined to be glomerular function stage 1 (GF-1), eGFR between 60 and 90 mL/min/1.73 m2 defined as GF-2, eGFR between 45 and 60 mL/min/1.73 m2 as GF-3A, and eGFR between 15 and 45 mL/min/1.73 m2 as GF-3B/4. Regression models stratified by GF-stages were fitted to estimate associations between the observed levels of blood and urine cadmium across stages of GF. Based on the results of stratified modes, there were consistent increases in adjusted geometric means (AGMSM) for both blood and urine cadmium from GF-1 to GF-3A although increases were not uniform from one GF stage to another. For the total population, AGMSM for blood and urine cadmium were GF-1 (0.47, 0.24), GF-2 (0.60, 0.37), GF-3A (0.72, 0.45), and GF-3B/4 (0.73, 0.45) μg/L. respectively. Although females had higher AGMSMs than males for both blood and urine cadmium, the difference in blood cadmium narrowed as kidney function deteriorated. Smokers had the steepest increases in AGMSMs for blood and urine cadmium across the stages of glomerular function and smoker-nonsmoker differences for blood cadmium narrowed as kidney function deteriorated but smoker-nonsmoker differences for urine cadmium widened as kidney function deteriorated. The important physiologic messages are that both blood and urine cadmium cease to increase from GF-3A to GF-3B/4, suggesting a new steady state based on renal failure. And, the narrowed difference in blood cadmium in smokers vs. nonsmokers suggests why this happens. Incremental exposures to cadmium are offset by excretion as renal failure progresses.
Mostrar más [+] Menos [-]A radiological index for evaluating the impact of an abandoned uranium mining area in Salamanca, Western Spain
2020
The establishment of a screening index would be a powerful tool to decide whether abandoned uranium mining areas should be rehabilitated or decommissioned. Thus, in this work we established a radiological index which uses the activity concentrations of different groups of gamma emitters from the natural radioactive series of ²³⁸U, ²³⁵U, and ²³²Th, as well as ⁴⁰K and ¹³⁷Cs. These activity concentrations were calculated by using the absorbed gamma radiation dose value of 175 nGy h⁻¹ specified in the U.S. Code of Federal Regulations. We studied our index in an abandoned uranium mining area in Salamanca, Western Spain, and found that the most influential factors in this area were the presence of organic matter in the soil and the possible effect that plants and fungi may have on the retention of these aforementioned radionuclides. In addition, the results showed that contaminants are migrating in an easterly direction in line with the prevailing wind direction and we were able to identify areas in which the radiological risk is likely high. The mean effective dose rate was 2.51 ± 0.98 mSv y⁻¹ which was equivalent to the levels obtained in previous works.
Mostrar más [+] Menos [-]Exposure to air pollution during the first 1000 days of life and subsequent health service and medication usage in children
2020
Evidence of health effects following early life exposure to short-to-medium duration of high pollution levels is extremely limited.We aimed to evaluate the associations between: 1. intrauterine exposure to fine particulate matter (PM2.5) from coal mine fire emissions and the frequencies of general practitioner attendances and dispensations of prescribed asthma inhalers, steroid skin creams, and antibiotics during the first year of life; 2. infant exposure and those outcomes during the year following the fire.All participants were recruited from the Latrobe Valley of Victoria, Australia. Participants’ 24-h average and hourly peak mine fire-specific PM2.5 exposures from 09/02/2014 to 31/03/2014 were estimated using chemical transport modelling. Outcome data were obtained from the Australian Medicare Benefits Schedule and Pharmaceutical Benefits Scheme from each child’s birth to 31/12/2016. We used negative binomial and logistic regression models to independently assess risks of the outcomes associated with every 10 and 100 μg m−3 increase in average or peak PM2.5 exposure, respectively, while adjusting for potential confounders.We included 286 of 311 children whose parents consented to be linked, comprising 77 with no exposure, 88 with intrauterine exposure and 121 with exposure in infancy. 10- and 100- μg m−3 increases in average and peak PM2.5 exposure during infancy were associated with greater incidence of antibiotics being dispensed during the year following the fire: the adjusted incidence rate ratios were 1.24 (95% CI 1.02, 1.50, p = 0.036) and 1.14 (1.00, 1.31, p = 0.048) respectively. No other significant associations were observed.Exposure to coal mine fire emissions during infancy was associated with increased dispensing of antibiotics. This could reflect increased childhood infections or increased prescriptions of antibiotics in the year following the fire.
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