Applicability of Brassica juncea as a bioindicator for As contamination in soil near the abandoned mine area.

Soil monitoring in abandoned mine areas is important from the perspective of ecological and human health risk. Arsenic (As) is a predominant metalloid contaminant in abandoned mine area and its behavior has been influenced by various soil characteristics. Bioindicator can be a useful tool in terms of testing the extent to which they are uptaken by plants bioavailability. Eighteen soils near the mine tailings dam were collected to investigate the effect of As contamination on As absorption by Brassica juncea. The pH range of the experimental soils was between 4.90 and 8.55, and the total As concentrations were between 34 mg kg-1 and 3017 mg kg-1. The bioavailability of As was evaluated by Olsen method, and B. juncea was cultivated in eighteen soils for 3 weeks. Principal component analysis, correlation, and multiple regression analysis were performed to estimate a significant factor affecting As uptake by B. juncea. All statistical results indicated that As bioavailability in soil is the main factor affecting As uptake in root and shoot of B. juncea. Although translocation process, the amount of As in shoot was exponentially explained by As bioavailability in soil. This result suggests that the contamination and bioavailability of As can be confirmed only by analyzing the shoot of B. juncea, which is be easily found in environmental ecosystem, and implies the applicability of B. juncea as a bioindicator for the monitoring of As contamination and its behavior in soil ecosystem.

Development of a Protocol for the Direct Breastfeeding of Premature Infants in Neonatal Intensive Care Units.

PURPOSE: This study aimed to develop a direct breastfeeding protocol for premature infants admitted to neonatal intensive care units (NICUs) and investigate its efficacy. BACKGROUND: Direct breastfeeding increases the amount and duration of breastfeeding. However, NICUs have low direct feeding rates owing to medical staff anxiety, lack of knowledge and experience, and fear of overwork. Accordingly, this study developed a protocol for direct breastfeeding in the NICU and evaluated its effect. METHODS: The protocol was developed through a literature review, expert validation, and preliminary investigation. Its application effects were identified using a nonexperimental, evidence-based research design targeting premature infants, their mothers, and NICU nurses. RESULTS: The protocol comprised 5 areas and 23 items. Application of the protocol resulted in continuous weight gain of the infants and increased self-efficacy in the mothers' direct breastfeeding ( t = 3.219, P = .004). Significant increases were noted in NICU nurses' direct breastfeeding activities ( t = 3.93, P < .001), breastfeeding rates in the NICU ( P = .037), and direct breastfeeding rates ( P = .007). CONCLUSIONS: Results underscore the value of an evidence-based protocol for improving breastfeeding rates in premature infants. This study highlights the need for continuous nursing education on protocol applications and human resource support.

Effect of bioavailable arsenic fractions on the collembolan community in an old abandoned mine waste.

Mine waste from abandoned mines poses a risk to soil ecosystems due to the dispersion of arsenic (As) in the mine waste to the nearby soil environment. Because the bioavailability of As varies depending on the As chemical fraction and exposure conditions, chemical assessment of As fractions in soil around mine waste is essential to understand their impact on soil ecosystem. Here, six sites around the mine waste were selected for investigating toxic effects of As-contaminant soil on Collembola community. To measure the As chemical fraction in soil and bioavailability, Wenzel sequential extraction employed. Meanwhile, the collembolans that live in each sampling site were identified at the species level, and the characteristics and composition of the collembola community were investigated. The mobility fraction (F1 + F2 + F3; MF) was related to the risk to the collembolan community, and the adverse impact of high MF appeared to lead to a decrease in abundance, richness, and Shannon index. According to non-metric multidimensional scaling analysis, F1, F2, F3, and pH were shown as the significant factor explaining the NMDS space. Especially, the sampling site with the highest concentration of F3 showed statistically different species composition from the other sites. In the case of As-contaminated soil around the old mine waste, the toxic effects of the remaining F3 in soil, as well as that of F1 and F2, should be fully considered. This study suggested that collembolan community could be used for understanding the impact of bioavailable As fraction in the old abandoned mine area.

The effectiveness of spent coffee grounds and its biochar on the amelioration of heavy metals-contaminated water and soil using chemical and biological assessments.

Spent coffee grounds (SCG) and charred spent coffee grounds (SCG-char) have been widely used to adsorb or to amend heavy metals that contaminate water or soil and their success is usually assessed by chemical analysis. In this work, the effects of SCG and SCG-char on metal-contaminated water and soil were evaluated using chemical and biological assessments; a phytotoxicity test using bok choy (Brassica campestris L. ssp. chinensis Jusl.) was conducted for the biological assessment. When SCG and SCG-char were applied to acid mine drainage, the heavy metal concentrations were decreased and the pH was increased. However, for SCG, the phytotoxicity increased because a massive amount of dissolved organic carbon was released from SCG. In contrast, SCG-char did not exhibit this phenomenon because any easily released organic matter was removed during pyrolysis. While the bioavailable heavy metal content decreased in soils treated with SCG or SCG-char, the phytotoxicity only rose after SCG treatment. According to our statistical methodology, bioavailable Pb, Cu and As, as well as the electrical conductivity representing an increase in organic content, affected the phytotoxicity of soil. Therefore, applying SCG during environment remediation requires careful biological assessments and evaluations of the efficiency of this remediation technology.

Crystallization-based upcycling of iron oxyhydroxide for efficient arsenic capture in contaminated soils.

Arsenic (As)-contaminated soil inevitably exists in nature and has become a global challenge for a sustainable future. Current processes for As capture using natural and structurally engineered nanomaterials are neither scientifically nor economically viable. Here, we established a feasible strategy to enhance As-capture efficiency and ecosystem health by structurally reorganizing iron oxyhydroxide, a natural As stabilizer. We propose crystallization to reorganize FeOOH-acetate nanoplatelets (r-FAN), which is universal for either scalable chemical synthesis or reproduction from natural iron oxyhydroxide phases. The r-FAN with wide interlayer spacing immobilizes As species through a synergistic mechanism of electrostatic intercalation and surface chemisorption. The r-FAN rehabilitates the ecological fitness of As-contaminated artificial and mine soils, as manifested by the integrated bioassay results of collembolan and plants. Our findings will serve as a cornerstone for crystallization-based material engineering for sustainable environmental applications and for understanding the interactions between soil, nanoparticles, and contaminants.

The Effects of Various Amendments on Trace Element Stabilization in Acidic, Neutral, and Alkali Soil with Similar Pollution Index.

Many studies have examined the application of soil amendments, including pH change-induced immobilizers, adsorbents, and organic materials, for soil remediation. This study evaluated the effects of various amendments on trace element stabilization and phytotoxicity, depending on the initial soil pH in acid, neutral, and alkali conditions. As in all types of soils, Fe and Ca were well stabilized on adsorption sites. There was an effect from pH control or adsorption mechanisms on the stabilization of cationic trace elements from inorganic amendments in acidic and neutral soil. Furthermore, acid mine drainage sludge has shown great potential for stabilizing most trace elements. In a phytotoxicity test, the ratio of the bioavailable fraction to the pseudo-total fraction significantly affected the uptake of trace elements by bok choy. While inorganic amendments efficiently decreased the bioavailability of trace elements, significant effects from organic amendments were not noticeable due to the short-term cultivation period. Therefore, the application of organic amendments for stabilizing trace elements in agricultural soil requires further study.