• Journal of Soil and Groundwater Environment
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• v.20 no.7
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• pp.103-111
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• 2015

Soil washing with ethylenediaminetetraacetic acid (EDTA) is highly effective in the remediation of soils contaminated with heavy metals. The EDTA recycling process is a requisite for reducing the operating cost. The applicability of Na₂S addition on the precipitation of heavy metals from the spent soil washing solution and thereby recycling of EDTA was investigated. Addition of Na₂S into the single metal-EDTA and the mixed metal-EDTA solutions ([Na₂S]/[metal-EDTA] ratio = 30, reaction time = 30 min and pH = 7~9) was highly effective in the separation of Cu and Pb from metal-EDTA complexes, but not for Ni. The Zn removal efficiency varied with pH and slightly increased upto 40% as the reaction time increased from 0 to 240 min which was longer than those for Cu and Pb. Ca(OH)₂ was subsequently added to induce further precipitation of Zn and Ni and to reduce the Na₂S dose. At the [Na₂S]/[metal-EDTA] ratio of 10, the removal efficiencies of all heavy metals excluding Ni were above 98% with the dose of Ca(OH)₂ at 0.002, 0.006 and 0.008 g into 100 mL of Cu-, Pb- and Zn-EDTA solutions, respectively. However, Ca(OH)₂ addition was not effective for Ni-EDTA solution. A further research is needed to improve metal removal efficiency and subsequent EDTA recycling for the real application in field-contaminated soils.

• Korean Journal of Poultry Science
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• v.11 no.1
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• pp.27-32
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• 1984

In order to use the liquid whole eggs as an ingredients of retorted products, the provention of the green-grey discoloration of retorted liquid whole eggs by the addition of the Na$_2$EDTA was investigated. And palatability change of the retorted liquid whole eggs by the addition of Na$_2$EDTA was also investigated. The results obtained were summarized as follows: 1. More severe green-grey discoloration was occurred when higher cooking temperature and longer cooking time were used. 2. Green-grey discoloration of retorted liquid whole eggs could be prevented by the addition of about 0.015% of Na$_2$EDTA. 3. The palatability of retorted liquid whole eggs was not lowered by the addition of 0.02% of Na$_2$EDTA and green grey discoloration was not developed during the storage time of 22 days at room temperature.

• 한국문화재보존과학회:학술대회논문집
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• 2005.11a
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• pp.122-134
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• 2005

XRF, EDX, IR analysis was conducted to figure the effect of Fe to blacken the waterlogged wood. The results showed that investigated soil contained more Fe than normal soil by XRF analysis and wood ash contained more sulfur and Fe than any other element by EDX analysis. C-H and C-O peaks were significantly reduced at the surface of wood where is blackened part of waterlogged wood by IR analysis. The optimum condition to remove Fe from waterlogged wood by EDTA was investigated. To do this, removed concentration of Fe was measured at various concentration of EDTA-2Na. The optimum pH of EDTA-2Na was figured to be 4.1 to 4.3 and as the concentration of EDTA was increasing, extracted concentration of Fe was also increased. In the case of 0.4 wt% of EDTA-2Na, 700ppm of Fe was eliminated and was stabilized after 48 hours time lapse. In the case of EDTA-3Na, the optimum pH was 7 to 8, and 10 ppm of Fe was eliminated at 0.4 wt% of EDTA-3Na. In the case of EDTA-4Na, the optimum pH was 10 to 11, and 120 ppm of Fe was eliminated at 0.4 wt% of EDTA-4Na.

• Restorative Dentistry and Endodontics
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• v.31 no.5
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• pp.378-389
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• 2006

The purpose of this study was to compare the sealing ability of root canal obturation with or without the treatment of smear layer. Eighty extracted human teeth with one canal were selected Instrumentation was performed with crown-down technique. After instrumentation, root canals of the NaOCl group and NaOCl-6 group were irrigated with 3% NaOCl. EDTA group and EDTA-6 group were irrigated with 17% EDTA. Then all teeth were obturated using continuous wane obturation technique NaOCl group and EDTA group were immersed in methylene blue solution for 84hours. NaOCl-6 group and EDTA-6 group were immersed in methylene blue solution for 6months. The teeth were sectioned at 1.5 mn (Level 1), 3.0 mm (Level 2) and 4.5 mm (Level 3) from the root apex. The length of dye-penetrated inter-face and the circumferential length of canal at each level were measured using Sigma-Scan Pro 5.0. 1. The mean leakage ratio was decreased cervically. 2. NaOCl group showed higher mean leakage ratio than EDTA group at each level. But there was significant difference at level 1 only (p < 0.05). 3. NaOCl-6 group showed higher mean leakage ratio than EDTA-6 group at each level. But there was significant difference at level 1 only (p < 0.05). 4. NaOCl-6 group showed higher mean leakage ratio than NaOCl group at each level. But there was significant difference at level 1 only (p < 0.05). 5. EDTA-6 group showed higher mean leakage ratio than EDTA group at each level. But there was no significant difference. 6. In NaOCl group and NaOCl-6 group, scanning electron micrographs of tooth sections generally covered with smear layer. In EDTA group and EDTA-6 group, tooth sections showing the penetration of sealers to opened dentinal tubules. The results suggest that removal of smear layer was effective to reduce the apical microleakage of the root canal.

• Korean Journal of Food Science and Technology
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• v.24 no.4
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• pp.387-392
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• 1992

In order to improve the solids and protein concentration and their yields in sea mustard extracts, HCl, sucrose, NaCl, EDTA, and SHMP were added during aqueous extraction and studied their effects on quality characteristics of the extracts. The extracts were prepared by 2 hours of boiling of ground sea mustard and centrifugation. Addition of HCl at $0.1{\sim}0.5N$ level was found that the solids and protein yields was significantly improved along with the ratio of supernatant seperated. The maximum solids and protein yields obtained were 52.48%, 36.73%, respectively, while those values of the aqueous extract without HCl were 23.20%, and 4.87%. Viscosity was reduced from 450 cps to less than 20 cps by HCl addition. When NaCl, sucrose, SHMP, and $Na_2EDTA$ were added in the concentration of range of $0.5{\sim}3.0%$, solid concentration and yields were also significantly improved by the order of $Na_2EDTA-SHMP-sucrose-NaCl$ in their effect. The highest solid yield of 55.0% was obtained from 3% addition of $Na_2EDTA$. Viscosity and turbidity were also reduced by addition of SHMP and $Na_2EDTA$.

• Korean Journal of Heritage: History & Science
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• v.40
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• pp.413-430
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• 2007

This study analyzed the foreign substances in waterlogged archaeological woods and compounds in soil where waterlogged archaeological wood was buried, in order to examine the relationship between burial environment and foreign substances in waterlogged archaeological wood. The XRF(X-ray Fluorescence Spectroscopy) and EDX(Energy Dispersive X-ray) analysis were conducted to examine the effect of iron(Fe) to blacken the waterlogged wood. The XRF results showed that investigated soil contained Si, Al, and Fe. Wood ash contained more sulfur and Fe than any other elements in the EDX analysis. Cellulose and hemicellulose were significantly reduced at the surface of wood, which is the blackened part of waterlogged wood. Foreign substances changed the surface color. These problems could be solved by removal of foreign substances in waterlogged archaeological wood using EDTA(Ethylene Diamine Tetra Acetic acid). The optimum condition to remove Fe from waterlogged wood by EDTA was investigated. To do this, the concentration of Fe removed was measured with various concentration of EDTA-2Na. The optimum pH of EDTA-2Na was figured to be 4.1 to 4.3. As the concentration of EDTA increased, the extracted concentration of Fe also increased. In the case of 0.4 wt% of EDTA-2Na, about 60ppm of Fe was eliminated and was stabilized after 48 hours. In the case of EDTA-3Na, the optimum pH was 7 to 8, and about 10 ppm of Fe was eliminated at 0.4 wt% of EDTA-3Na. In the case of EDTA-4Na, the optimum pH was 10 to 11, and about 20 ppm of Fe was eliminated at 0.4 wt% of EDTA-4Na. In conclusion, the iron(Fe) in waterlogged archaeological wood was removed by EDTA treatment and it increased the whiteness of the surface.

• Restorative Dentistry and Endodontics
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• v.31 no.3
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• pp.169-178
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• 2006

This study was to verify that the combined application of NaOCl and EDTA was more effective in removal of smear layer than the application of NaOCl alone. furthermore it was aimed to find out the optimal time for the application of EDTA. Thirty five single rooted teeth were cleaned and shaped. NaOCl solution was used as an irrigant during instrumentation. After instrumentation, root canals of the control group were irrigated with 5 ml of NaOCl for 2 minutes. 30 sec, 1 min, and 2 min group were irrigated with 5 ml of 17% EDTA for 30 sec, 1 min, and 2 min respectively. Then the roots were examined with scanning electron microscopy for evaluating removal of smear layer and erosion of dentinal tubule. The results were as follows; 1. The control group: The smear layer was not removed at all. 2. The other groups: 1) $Middle\frac{1}{3}$: All groups showed almost no smear layer. And the erosion occurred more frequently as increasing irrigation time. 2) $Apical\frac{1}{3}$: The cleaning effect of 2 min group was better than the others. The results suggest that 2 min application of 17% EDTA should be adequate to remove smear layer on both $apical\frac{1}{3}\;and\;middle\frac{1}{3}$.

• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.1
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• pp.37-44
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• 2013

Sodium hypochlorite and ethylene diamine tetra acetic acid are substances usually used during endodontic treatment. Several studies found that the bonding was negated with certain irrigants and some of the used irrigants have demineralizing and chealating effects, so it was advocated to omit the etching step in etch and rinse adhesive systems. The purpose of this in vitro study was to evaluate the influence of NaOCl & EDTA on the bonding strength of ethanol wet bonding. Thirty human molars were selected and mesiodistally sectioned into halves, thus providing sixty specimens. The specimens were randomly assigned to 4 groups(n=15) according to the irrigant regimen used : (1) irrigated with distilled water for 10min (control); (2) irrigated with 5.25% NaOCl(10min), flushed with 5.25% NaOCl(1min) (3) irrigated with 5.25% NaOCl, flushed with 17% EDTA (4) irrigated with 5.25% NaOCl, flushed with 17% EDTA. Each group was acid-etched with 37% phosphoric acid(except group 4) and had their dentin surfaces dehydrated with ethanol solutions : 50%, 70%, 80%, 95%, 3x100%, 30s for each application. After dehydration, a primer( 50% all bond 3 resin + 50% ethanol) was used, followed by the adhesive(ALL-BOND 3 RESIN) application. Resin composite build-ups were then prepared using an incremental technique. Specimens were sectioned into beams and submitted to a tensile load using a Micro Tensile Tester(Bisco Inc.). The data were statistically analyzed using one-way ANOVA and Tukey HSD at p<0.5 level. There was no significant difference on G1(control) and G2(irrigated with NaOCl only ). (p>0.05). G3(flushed with EDTA) showed significantly high tensile bonding strength compared to the G2 (p<0.05). G4( treated with EDTA but no acid-etching) was significantly lower value than G3. (p<0.05) Although there was no significant difference, 5.25% NaOCl seemed to have an adverse effect on the bonding strength of ethanol wet bonding. The flushing with EDTA after NaOCl irrigation prevents the decrease of bonding strength. The use of 17% EDTA as a final flush can enhance the bonding strength but EDTA flushing can't substitute for a acid-etching.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.8
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• pp.1130-1134
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• 2005

An experiment was performed using 20 calves of about one-month old to investigate the effect of chelation therapy with calcium disodium ethylenediaminetetraacetate ($CaNa_2$EDTA) alone or along with antioxidant $\alpha$-tocopherol in lead loaded calves on blood trace minerals, erythrocytic sulfahydryl groups and some haematobiochemical parameters. Fifteen calves were given lead orally at a daily dose of 7.5 mg of 99% pure lead acetate/kg body weight for 28 days. Then the lead was withdrawn on day 28 and the calves were randomly divided into three groups. Each group of five animals was either treated with $CaNa_2$EDTA alone at the dose rate of 110 mg/kg body weight in two divided doses for 4 days or along with $\alpha$-tocopherol at the dose rate of 100 mg/kg body weight orally daily for 7 days, keeping the remaining five calves as lead-exposed untreated controls. Blood samples were collected at the end of the lead exposure (day 0) and thereafter on day 2, 4, 7 and 10 from the start of the chelation treatment. The treatment with EDTA alone led to slow but non-significant improvement in blood copper level, but incorporation of antioxidant $\alpha$-tocopherol in chelation therapy resulted in its significant decline, as recorded on day 7-post treatment. Withdrawal of lead or treatment with $CaNa_2$EDTA alone or along with $\alpha$-tocopherol enhanced the erythrocytic thiol contents and the levels of T-SH and P-SH became statistically (p<0.05) comparable to those of lead-exposed controls by day 7 and 4, respectively. There was no significant (p>0.05) change in serum urea, creatinine, total protein and albumin levels between the treatment groups. It is concluded from the present investigation that treatment with $CaNa_2$EDTA at the present dose rate is safe to be used for chelation in lead loaded calves.

• Restorative Dentistry and Endodontics
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• v.34 no.6
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• pp.484-490
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• 2009

The purpose of this study was to evaluate the effect of soft chelating irrigant on the sealing ability of root fillings by using a glucose leakage test. A total of 45 single-rooted teeth were selected for the study. The teeth were decoronated leaving a total length of 13mm. The root canals prepared using K3 NiTi rotary instruments to an apical dimension of size 45(0.06 taper). The specimens were then randomly divided into 3 experimental groups of 13 roots each and 2 control groups of 3 roots each. Specimen in each group were prepared with different irrigation protocols : group 1, 2.5% NaOCl; group 2, 2.5% NaOCl and 17% EDTA: group 3, 2.5% NaOCl and 15% HEBP. The root canals were filled with gutta-percha and AH Plus sealer using lateral condensation. After 7 days in $37^{\circ}C$, 100% humidity, the coronal-to-apical microleakage was evaluated quantitatively using a glucose leakage model. The leaked glucose concentration was measured with spectrophotometry at 1, 4, 7, 14, 21 and 28 days. There was a tendency of increase in leakage in all experimental groups during experimental period. HEBP-treated dentin showed no significant difference with EDTA-treated dentin during experimental period. From the 21th day onward, HEBP-treated dentin showed significantly lower leakage than smear-covered dentin. HEBP-treated dentin displayed a similar sealing pattern to EDTA-treated dentin and a better sealing ability than smear-covered dentin. Consequently, a soft chelator(HEBP) could be considered as the possible alternative to EDTA.