Flanaganbowen5317
The performance of a lab-scale biotrickling filter (BTF) inoculated with a mixed fungal consortium was investigated for the simultaneous abatement of 2-ethylhexanol; a hydrophobic semi-volatile organic compound (SVOC), and propylene glycol monomethyl ether (PGME). The BTF performance was investigated in the presence of lipopeptide-type biosurfactant, surfactin. The effect of surfactin on the removal efficiency and elimination capacity was examined at stretched inlet loading rates (LR) 1.04 to 15.7 and 3.2-48 g m-3 h-1 of PGME and 2-ethylhexanol, respectively. Seeding the BTF with 50 mg L-1 of surfactin maintained high and consistent removal efficiencies of PGME and 2-ethylhexanol up to LRs of 15.7 and 32 g m-3 h-1, with removal efficiencies of 98.5 and 99%, respectively. Once the LR of 2-ethylhexanol increased to 48 g m-3 h-1, a substrate inhibition was observed, accompanied by a sudden decrease in removal efficiency from 99.2 to 62.3%. At the same LR, the BTF performance was improved by reseeding 100 mg L-1 of surfactin, hence, reinstated the removal efficiency of 2-ethylhexanol to 92.7% and achieving a maximum elimination capacity of 44.5 g m-3 h-1. This enhanced SVOC uptake rate was further confirmed by a considerable increase in reaction rate constant from 0.005 to 0.017 s-1. A batch study was also conducted at the end of the experimental run to better understand the correlation between surfactin concentrations and the time-dependent partition coefficient of 2-ethylhexanol. Biofilm microbial community structure revealed relative abundancy of 72 and 28% of Trichoderma asperellum and Fusarium solani, respectively. The findings of this study show for the first time that the removal of a semi-VOC such as 2-ethylhexanol is feasible in the presence of surfactin and hence improving the bioavailability of hydrophobic semi-VOC.Exposure of humans to parabens is widespread and urinary parabens are widely used as exposure biomarkers. YD23 However, are the levels of these chemicals suitable to assess exposure to parabens? We conducted an intervention study by controlling the use of personal care products (PCPs) to explore the exposure of parabens. Ten female participants were recruited who were treated with different types of PCPs during the 18-day study period. The concentrations of parabens and their metabolites in matrices of different exposure pathways (dust, drinking water and dietary food) and urine samples were determined. We demonstrated that PCPs were the major sources of parabens, accounting for >99% of total exposure. The metabolites were nonspecific to individual parabens and could not be used as exposure biomarkers. Urinary paraben concentrations were positively correlated with external exposure levels. However, poor reproducibility was observed, with intraclass correlation coefficients (ICC) ranging from 0.125 to 0.295 in unadjusted urinary concentrations. Creatinine-adjusting could not significantly improve the ICC values in random spot samples. After adjusting for both creatinine and kinetic models, the ICC values ranged from 0.695 to 0.886, indicating a good reproducibility. So, toxicokinetic parameters may be taken into consideration for precise monitoring of exposures for the non-persistent pollutants.On January 2019, the B1 iron ore tailings' dam collapsed in Brumadinho, Brazil, being one of the worst mining-related disasters, with 270 human deaths (11 of them still missing) and 12.106 m3 of tailings released to the environment. The tailings devastated the Córrego do Feijão brook and reached the adjacent Paraopeba River, the region's main watercourse and a major tributary of the São Francisco basin. Although physicochemical parameters of the river were strongly impacted, and acute toxicological effects have been reported from exposure experiments, contamination of aquatic biota had not yet been assessed. Therefore, the aim of this study was to evaluate contamination by trace elements (As, Al, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb and Zn) in sediment, fish and macrophytes along the Paraopeba River, upstream and downstream from the dam failure site, during the dry and wet season. With the exception of Cd and Hg, all elements in sediment samples had lower median concentrations downstream. An inverse pattern was observed for the aquatic biota, with significant higher concentrations of Fe, Mn, Ni and Zn in fishes, and increased concentrations of most elements in macrophytes, indicating an increase in element bioavailability. A significant seasonal variation was observed with increased concentrations of As (dry season) and Pb (wet season) in fish samples, with the same trend occurring in macrophytes. Concentrations of potentially toxic elements in fish samples in wet weight (Cr 1.80 ± 1.31 mg kg-1, Hg 0.21 ± 0.11 mg kg-1 and Pb 0.79 ± 0.80 mg kg-1) were lower than those reported before the disaster. Furthermore, As and Pb concentrations exceeded the safety threshold for fish consumption in 3% and 41% of samples, respectively, representing a matter of concern for public health.
The widespread exploitation and application of rare earth elements (REE) have led to the risk of human exposure and might result in the adverse health effect on pregnant women. However, no epidemiological studies have explored the associations between prenatal REE exposure and premature rupture of membranes (PROM).
We aimed to investigate the associations of maternal urinary REE levels with the risk of PROM.
A total of 4897 mother-newborn pairs were recruited from a birth cohort study in Wuhan, China. Urinary concentrations of REE were measured by inductively coupled plasma mass spectrometry (ICP-MS). The associations of prenatal REE exposure with PROM were evaluated using logistic regression models. False discovery rate (FDR) was applied to adjust for multiple testing. Weighted quantile sum (WQS) regression was used to estimate the association of urinary REE mixture with PROM.
With one unit increase (μg/g creatinine) in natural log-transformed urinary REE levels (Ce, Yb, La, Pr, Nd, Eu, Gd, Dy, Ho, Es.Aneurysmal subarachnoid hemorrhage (aSAH) is a devastating disease, which mainly caused by the rupture of an intracranial aneurysm. Clinical trials have demonstrated that cerebral vasospasm (CVS) is not the sole contributor to delayed cerebral ischemia (DCI) and poor outcomes in patients with aSAH. Currently, accumulating evidence suggests that early brain injury (EBI), which occurs within 72 h after the onset of aSAH, lays the foundation for subsequent pathophysiological changes and poor outcomes of patients. The pathological mechanisms of EBI mainly include increased intracranial pressure, oxidative stress, neuroinflammation, blood-brain barrier (BBB) disruption, cerebral edema and cell death. Among them, the brain immune inflammatory responses involve a variety of immune cells and active substances, which play an important role in EBI after aSAH and may be related to DCI and long-term outcomes. Thus, attention should be paid to strategies targeting cerebral immune inflammatory responses. In this review, we discuss the role of immune inflammatory responses in the occurrence and development of aSAH, as well as some inflammatory biomarkers related to CVS, DCI, and aSAH outcomes.