Sources, distribution, bioavailability, toxicity, and risk assessment of heavy metal(loid)s in complementary medicines

Bolan, Shiv,Kunhikrishnan, Anitha,Seshadri, Balaji,Choppala, Girish,Naidu, Ravi,Bolan, Nanthi S.,Ok, Yong Sik,Zhang, Ming,Li, Chun-Guang,Li, Feng,Noller, Barry,Kirkham, Mary Beth Elsevier 2017 Environment international Vol.108 No.-

<P><B>Abstract</B></P> <P>The last few decades have seen the rise of alternative medical approaches including the use of herbal supplements, natural products, and traditional medicines, which are collectively known as ‘Complementary medicines’. However, there are increasing concerns on the safety and health benefits of these medicines. One of the main hazards with the use of complementary medicines is the presence of heavy metal(loid)s such as arsenic (As), cadmium (Cd), lead (Pb), and mercury (Hg). This review deals with the characteristics of complementary medicines in terms of heavy metal(loid)s sources, distribution, bioavailability, toxicity, and human risk assessment. The heavy metal(loid)s in these medicines are derived from uptake by medicinal plants, cross-contamination during processing, and therapeutic input of metal(loid)s. This paper discusses the distribution of heavy metal(loid)s in these medicines, in terms of their nature, concentration, and speciation. The importance of determining bioavailability towards human health risk assessment was emphasized by the need to estimate daily intake of heavy metal(loid)s in complementary medicines. The review ends with selected case studies of heavy metal(loid) toxicity from complementary medicines with specific reference to As, Cd, Pb, and Hg. The future research opportunities mentioned in the conclusion of review will help researchers to explore new avenues, methodologies, and approaches to the issue of heavy metal(loid)s in complementary medicines, thereby generating new regulations and proposing fresh approach towards safe use of these medicines.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A first-time comprehensive overview on the health risk assessment of heavy metal(loid)s in complementary medicines </LI> <LI> Ayurvedic medicines contain toxic levels of heavy metal(loid)s including As, Cd, Hg and Pb </LI> <LI> The bioavailability of metal(loid)s in complementary medicines depends on speciation of these metals </LI> <LI> Regular intake of some complementary medicines has caused metal(loid) toxicity in humans </LI> <LI> Health risk assessment can be achieved based on the daily intake of complementary medicines and total metal(loid) content </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Interactions between heavy metal(loid)s and complementary medicines.</P> <P>[DISPLAY OMISSION]</P>

Effect of Triticale Dried Distillers Grains with Solubles on Ruminal Bacterial Populations as Revealed by Real Time Polymerase Chain Reaction

Wu, R.B.,Munns, K.,Li, J.Q.,John, S.J.,Wierenga, K.,Sharma, R.,Mcallister, T.A. Asian Australasian Association of Animal Productio 2011 Animal Bioscience Vol.24 No.11

Real time PCR was used in this study to determine the effect of triticale dried distillers grains with solubles (TDDGS) as a replacement for grain or barley silage in finishing diets on the presence of six classical ruminal bacterial species (Succinivibrio dextrinosolvens, Selenomonas ruminantium, Streptococcus bovis, Megasphaera elsdenii, Prevotella ruminicola and Fibrobacter succinogenes) within the rumen contents of feedlot cattle. This study was divided into a step-wise adaptation experiment (112 days) that examined the effects of adaptation to diets containing increasing levels of TDDGS up to 30% (n = 4), a short-term experiment comparing animals (n = 16) fed control, 20%, 25% or 30% TDDGS diets over 28 days, and a rapid transition experiment (56 days) where animals (n = 4) were rapidly switched from a diet containing 30% TDDGS to a barley-based diet with no TDDGS. It was found that feeding TDDGS as replacement for barley grain (control vs. 20% TDDGS) decreased 16S rRNA copy numbers of starch-fermenting S. ruminantium and S. bovis (p<0.001 and p = 0.04, respectively), but did not alter 16S rRNA copy numbers of the other rumen bacteria. Furthermore, feeding TDDGS as a replacement barley silage (20% vs. 25% and 30% TDDGS) increased 16S rRNA copy numbers of S. ruminantium, M. elsdenii and F. succinogenes (p<0.001; p = 0.03 and p<0.001, respectively), but decreased (p<0.001) the 16S rRNA copy number of P. ruminicola. Upon removal of 30% TDDGS and return to the control diet, 16S rRNA copy numbers of S. ruminantium, M. elsdenii and F. succinogenes decreased (p = 0.01; p = 0.03 and p = 0.01, respectively), but S. dextrinosolvens and S. bovis increased (p = 0.04 and p = 0.009, respectively). The results suggest that replacement of TDDGS for grain reduces 16S rRNA copy numbers of starch-fermenting bacteria, whereas substitution for barley silage increases 16S rRNA copy numbers of bacteria involved in fibre digestion and the metabolism of lactic acid. This outcome supports the contention that the fibre in TDDGS is highly fermentable.

Interactions of food waste compost with metals and metal-chelant complexes during soil remediation

Beiyuan, Jingzi,Tsang, Daniel C.W.,Bolan, Nanthi S.,Baek, Kitae,Ok, Yong Sik,Li, Xiang-Dong Elsevier 2018 JOURNAL OF CLEANER PRODUCTION Vol.192 No.-

<P><B>Abstract</B></P> <P>For removing potentially toxic elements (PTEs) from field-contaminated soils, cost-effective soil remediation has been a worldwide concern. As one of the widely employed techniques, chelant-enhanced phytoremediation can remove PTEs with marginal impact on the soil properties, yet the newly formed metal-chelant complexes cannot be completely captured and extracted by the plants. This arouses concerns about downstream migration and secondary contamination of the metal-chelant complexes and free chelant. Organic amendments, such as food waste compost (FWC), may stabilize metals and/or metal-chelant complexes, improve soil properties and plant growth, and reduce waste volume. Therefore, FWC may provide a solution for the migration of metal-chelant complexes and free chelant. Two chelants were selected in this study: EDTA (ethylene-diaminetetraacetic-acid) and its biodegradable isomer EDDS ([<I>S,S</I>]-ethylenediaminedisuccinic acid). The interactions between FWC and metals, metal-EDTA/metal-EDDS complexes in a field-contaminated soil (mainly by Cu, Zn, and Pb) were investigated. Batch adsorption isotherms indicated a strong adsorption capacity of FWC for uncomplexed Cu, Zn, and Pb ions. Significant adsorption of Pb-EDDS (∼100%), Zn-EDDS (>77%), and Cu-EDTA (36–76%) complexes on the FWC was found at apparent equilibrium. The adsorption capacity of Cu-EDDS (32–38%), Pb-EDTA (∼20%), and Zn-EDTA (∼0%) complexes was limited. However, the co-existence of FWC and EDDS increased the mobilization of Cu and Zn, while the co-existence of FWC and EDTA reduced the available amounts of Cu and Pb in solution. Metal speciation calculation showed that nearly all extracted Cu, Zn, and Pb were complexed with chelants in the solution, while notable amount of dissolved Fe (but not Al and Ca) was associated with dissolved organic matter. In this study, FWC can be useful for minimizing the unintended leaching of Cu- and Pb-EDTA complexes in EDTA-enhanced phytoremediation, yet it might be less suitable for the case of EDDS. A novel integration of recycled waste can enhance the effectiveness of sustainable remediation of contaminated soils.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Large amounts of dissolved organic matter released from food waste compost (FWC). </LI> <LI> Cu, Zn, and Pb ions significantly adsorbed to FWC. </LI> <LI> Yet metal-EDDS/EDTA complexes showed diverse adsorption behaviours on FWC. </LI> <LI> Cu-EDDS complexes can be adsorbed to FWC yet the Cu mobility increased with FWC. </LI> <LI> FMC-derived DOM mitigated the EDTA-induced solubilization of Cu and Pb in soil. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Combined application of EDDS and EDTA for removal of potentially toxic elements under multiple soil washing schemes

Beiyuan, Jingzi,Tsang, Daniel C.W.,Valix, Marjorie,Baek, Kitae,Ok, Yong Sik,Zhang, Weihua,Bolan, Nanthi S.,Rinklebe, Jö,rg,Li, Xiang-Dong Elsevier 2018 CHEMOSPHERE - Vol.205 No.-

<P><B>Abstract</B></P> <P>Chelant-enhanced soil washing, such as EDTA (ethylenediaminetetraacetic acid) and biodegradable EDDS ([<I>S,S</I>]-ethylene-diamine-disuccinic acid), has been widely studied, however, EDTA is persistent under natural conditions while EDDS has a low efficiency for Pb extraction. Therefore, we investigated the efficacy of mixed chelants (EDDS and EDTA mixture at 1:1 M ratio) for the removal of Cu, Zn, and Pb from a field-contaminated soil using various washing schemes (multi-pulse, step-gradient chelant, and continuous washing schemes). Speciation modelling of the target metals, mineral elements, and EDDS/EDTA was performed, while the leachability and bioaccessibility of residual metals in the treated soils were also assessed. Our results suggested that the combined use of EDDS and EDTA reached equivalent extraction efficiency of the target metals as EDTA, i.e., 50% reduction in the dosage of EDTA was made possible. This was accomplished by selective extraction of Cu by EDDS and Pb by EDTA, which was supported by the results of speciation calculation. Multi-pulse washing scheme with intermittent water rinsing steps removed entrapped metal-chelant complexes and free chelants, therefore reducing the leachability and bioaccessibility of residual metals in the treated soils. Step-gradient chelant washing with the maximum dosage of chelants in the first washing step only achieved marginal improvement but undesirably promoted Pb bioaccessibility. Continuous washing for 24 h enhanced metal extraction but promoted mineral dissolution, together with a large amount of uncomplexed chelants and increase in Cu leachability. Thus the combined use of EDDS and EDTA in multi-pulse washing is recommended for further studies.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Mixture of EDDS and EDTA extracted comparable amount of PTEs as EDTA washing. </LI> <LI> Mixed chelants allowed complementary metal complexation and higher efficiency. </LI> <LI> Multi-pulse washing better utilized chelants and reduced leachability/bioaccessibility. </LI> <LI> Step-gradient chelant dosage hardly improved extraction but increased bioaccessible Pb. </LI> <LI> Continuous washing increased amounts of uncomplexed chelants and dissolved minerals. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

A combination of ferric nitrate/EDDS-enhanced washing and sludge-derived biochar stabilization of metal-contaminated soils

Yoo, Jong-Chan,Beiyuan, Jingzi,Wang, Lei,Tsang, Daniel C.W.,Baek, Kitae,Bolan, Nanthi S.,Ok, Yong Sik,Li, Xiang-Dong Elsevier 2018 Science of the Total Environment Vol.616 No.-

<P><B>Abstract</B></P> <P>In this study, soil washing and stabilization as a two-step soil remediation strategy was performed to remediate Pb- and Cu-contaminated soils from shooting range and railway sites. Ferric nitrate (Fe(NO<SUB>3</SUB>)<SUB>3</SUB>) and [<I>S,S</I>]-ethylenediamine disuccinate (EDDS) were used as washing agents, whereas three types of sludge-derived biochars and phosphogypsum were employed as soil stabilizers. While Fe(NO<SUB>3</SUB>)<SUB>3</SUB> extracted larger amounts of metals compared to EDDS (84% Pb and 64% Cu from shooting range soil; 30% Pb and 40% Cu from railway site soil), it caused severe soil acidification. Both Fe(NO<SUB>3</SUB>)<SUB>3</SUB> and EDDS washing enhanced the mobility of residual metals in the two soils, which in most cases could be mitigated by subsequent 2-month stabilization by sludge-derived biochars or phosphogypsum. By contrast, the metal bioaccessibility could only be reduced by soil washing. Nutrient-rich sludge-derived biochar replenished available P and K in both soils, whereas Fe(NO<SUB>3</SUB>)<SUB>3</SUB> washing provided available nitrogen (N). Soil amendment enhanced acid phosphatase activity but marginally improved soil dehydrogenase and urease activity in the treated soils, possibly due to the influence of residual metals. This study supported the integration of soil washing (by Fe(NO<SUB>3</SUB>)<SUB>3</SUB> or EDDS) with soil stabilization (by sludge-derived biochars or phosphogypsum) for accomplishing the reduction of metal mobility and bioaccessibility, while restoring the environmental quality of the treated soils.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Fe(NO<SUB>3</SUB>)<SUB>3</SUB> washing significantly removed Pb from shooting range and railway soils. </LI> <LI> Biochars neutralized acidic soil pH resulting from Fe(NO<SUB>3</SUB>)<SUB>3</SUB> washing. </LI> <LI> Phosphogypsum immobilized residual Pb by forming insoluble PbSO<SUB>4</SUB> precipitates. </LI> <LI> Sludge-derived biochars reduced metal mobility and enhanced soil quality. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

High-rate in-plane micro-supercapacitors scribed onto photo paper using <i>in situ</i> femtolaser-reduced graphene oxide/Au nanoparticle microelectrodes

Li, R.-Z.,Peng, Rui,Kihm, K. D.,Bai, S.,Bridges, D.,Tumuluri, U.,Wu, Z.,Zhang, T.,Compagnini, G.,Feng, Z.,Hu, A. The Royal Society of Chemistry 2016 ENERGY AND ENVIRONMENTAL SCIENCE Vol.9 No.4

<P>Direct laser-reduction of graphene oxide (GO), as a lithography-free approach, has been proven effective in manufacturing in-plane micro-supercapacitors (MSCs) with fast ion diffusion. However, the power density and the charge/discharge rate are still limited by the relatively low conductivity of electrodes. Here, we report a facile approach by exploiting femtolaser <I>in situ</I> reduction of the hydrated GO and chloroauric acid (HAuCl<SUB>4</SUB>) nanocomposite simultaneously, which incorporates both the patterning of rGO electrodes and the fabrication of Au current collectors in a single step. These flexible MSCs boast achievements of one-hundred fold increase in electrode conductivities of up to 1.1 × 10<SUP>6</SUP> S m<SUP>−1</SUP>, which provide superior rate capability (50% for the charging rate increase from 0.1 V s<SUP>−1</SUP> to 100 V s<SUP>−1</SUP>), sufficiently high frequency responses (362 Hz, 2.76 ms time constant), and large specific capacitances of 0.77 mF cm<SUP>−2</SUP> (17.2 F cm<SUP>−3</SUP> for volumetric capacitance) at 1 V s<SUP>−1</SUP>, and 0.46 mF cm<SUP>−2</SUP> (10.2 F cm<SUP>−3</SUP>) at 100 V s<SUP>−1</SUP>. The use of photo paper substrates enables the flexibility of this fabrication protocol. Moreover, proof-of-concept 3D MSCs are demonstrated with enhanced areal capacitance (up to 3.84 mF cm<SUP>−2</SUP> at 1 V s<SUP>−1</SUP>) while keeping high rate capabilities. This prototype of all solid-state MSCs demonstrates the broad range of potentials of thin-film based energy storage device applications for flexible, portable, and wearable electronic devices that require a fast charge/discharge rate and high power density.</P> <P>Graphic Abstract</P><P>Direct laser-reduction of graphene oxide (GO), as a lithography-free approach, has been proven effective in manufacturing in-plane micro-supercapacitors (MSCs) with fast ion diffusion. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c5ee03637b'> </P>

Structural, Morphological, and Optical Studies on Li-doped ZnO Thin Films Deposited by Using PLD

Guojie Li,S. Sambasivam,Saes Byul Kim,박성욱,정중현,전병억,최병춘 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.4

We report the structural and the optical properties of Zn_(1−x)Li_xO (x = 0.0, 0.02, 0.08, 0.12, 0.18) nanocrystalline thin films deposited on ?Al_2O_3 substrates by using pulsed laser deposition. X-ray diffraction (XRD) analysis revealed that all the films were single phase and had a hexagonal wurtzite structure. The lattice constant increased gradually with increasing Li content. Atomic force microscopy (AFM) showed that the grain size of the films was approximately 20 ?30 nm. Optical absorption studies in the wavelength range 200 ?900 nm revealed an increase in the band gap of the Li-doped ZnO films from 3.19 to 3.41 eV. Photoluminescence (PL) spectroscopy of these films was carried out. The luminescence observed was attributed to defects in the nanocrystalline Li-doped ZnO films, and the PL intensity decreased with increasing Li content.

19세기 성리학(性理學)의 쟁점과 그 의미

이상익 ( Sang Ik Lee ) 한국철학사연구회 2013 한국 철학논집 Vol.0 No.36

Weldability of Type 444 Ferritic Stainless Steel GTA Welds

Li, C.,Jeong, H.S. The Korean Welding and Joining Society 2003 International journal of Korean welding society Vol.3 No.1

The ferritic stainless steels are generally considered to have poor weldability compared with that of the austenitic stainless steels. However the primary advantages of ferritic stainless steels include lower material cost than the more commonly used austenitic stainless steels and a greater resistance to stress corrosion cracking. Thus, the weldability of ferritic stainless steels was investigated in this study. In concerning the weldability, Grain size measurement test, Erichsen test and Varestraint test were involved. full penetration welds were produced by autogeneous direct current straight polarity (DCSP) and pulsed currents gas tungsten arc welding (GIAW) and the effect of pulsed currents welding on the welds was compared to that of DCSP welding. The results showed that pulsed current was effective to refine grain size in the weld metal and the finest grain size was obtained at the frequency of 150Hz. In addition, the ductility of welds was lower than that of base metal. Finally, autogeneous type 444 welds were less susceptible to macro solidification cracks, but more sensitive to micro cracks; SEM/EDS analysis indicated that all the inclusions in the crack showed enrichment of Mn, Si, O and S.

유형별 완전혼합사료 급여가 반추위내의 발효성상 및 영양소 소화율에 미치는 영향

이덕윤,고종렬,최낙진,이상석,송재용,이세영,박성호,성하균,하종규 한국동물자원과학회 2003 한국축산학회지 Vol.45 No.5

This study was conducted to examine effects of feeding dry TMR(DTMR), wet TMR(WTMR) and fermented TMR(FTMR) on rumen fermentation, enzyme activity and digestibility in the total tract of sheep. Three rumen cannulated sheep were used in a 3 × 3 latin square design. The present results showed that ?, NH_(3)-N, total and individual VFA, A/P ratio and enzymes (CMCase, Xylanase and Protease) activity in the rumen were higher in WTMR and FTMR compared with DTMR. In addition, dry matter, organic matter, crude protein, ether extract, NDF and ADF digestibility in the total tract were also higher in WTMR and FTMR compared with DTMR. Therefore, the present results showed that WTMR and FTMr are better than DTMR for rumen fermentation and nutrients digestibility.