• Title/Summary/Keyword: comparative toxicity

Search Result 103, Processing Time 0.024 seconds

A Comparative Study on Adsorption of PCB Congeners in Mineral Oil by Activated Carbon (활성탄에 의한 광유내 PCB Congeners의 흡착에 관한 비교 연구)

  • Ryoo, Keon Sang
    • Journal of the Korean Chemical Society
    • /
    • v.41 no.5
    • /
    • pp.239-245
    • /
    • 1997
  • The sorption kinetic was studied to evaluate feasibility of removing PCBs from mineral oil with activated carbon. Adsorption efficiency for Aroclor 1242 which is composed of lower chlorinated PCB formulations was $\geq$ 95%, whereas the adsorption efficiency for Aroclor 1260 having higher chlorinated constituents was considerably lower with the efficiency falling to 75%. The observed difference in the adsorption efficiency is attributed to the geometry of PCBs with non-planar and coplanar structure. The concentration of coplanar PCBs is appreciably higher in Aroclor 1242. Since toxicity is primarily associated with coplanar congeners, the preferential adsorption of coplanar congeners by activated carbon accounts for the fact that toxicity reduction can be achieved through this process. The efficiency of process was assessed in terms of Toxicity Equivalence Factor (TEF).

  • PDF

Non-comparative Study for the Observation of Clinical Efficacy and Safety of CheungYeolYiSeup-tang and Hwangbaek External dressings on Dampness-Heat Pattern Atopic Dermatitis

  • Choi, In-Hwa
    • The Journal of Korean Medicine
    • /
    • v.29 no.5
    • /
    • pp.41-51
    • /
    • 2008
  • Objective : To observe the efficacy and safety of CheungYeolYiSeup-tang and Hwangbaek external dressings on dampness-heat pattern atopic dermatitis(AD) in a non-comparative study. Methods : 10 patients with AD were included for 4 weeks of treatment. Efficacy and safety assessment included the scoring atopic dermatitis index(SCORAD), typical signs and symptoms of AD, results of some laboratory tests related to toxicity, and the incidence of adverse events. Results : Improvements in efficacy parameters were observed and produced no significant changes in laboratory tests related to toxicity in these patients. Their SCORAD results significantly decreased after 4weeks(P value<.01, according to the Wilcoxon sum of ranks test). Similarly, significant reductions from baseline in subjective pruritus scores and (P value<.05 by the Wilcoxon sum of ranks test) and the mean average of individual signs and symptoms of AD were reported after 4 weeks(P value<.05, P<0.01 by the Wilcoxon sum of ranks test). There were no significant changes in eosinophil, neutrophil, lymphocyte, immunoglobulin E and ESR in blood serum by paired ttest. Conclusion :CheungYeolYiSeup-tang administration and Hwangbaek external dressings are an effective and safe treatment for the management of dampness-heat pattern atopic dermatitis.

  • PDF

Evaluation of Ecotoxicity and Characteristics on Indirect Effluents and Related Wastewater (간접방류사업장 관련 폐수의 생태독성수준 및 특성 평가)

  • Kim, Jongmin;Shin, Kisik;Lee, Soohyung;Lee, Jungseo;Lee, Taekjune
    • Journal of Korean Society on Water Environment
    • /
    • v.33 no.4
    • /
    • pp.481-486
    • /
    • 2017
  • This paper aims to evaluate the characteristics of direct and indirect effluents'toxicity level and difference between two test durations (24 h and 48 h) of test method. The proportion of the indirect effluent samples which exceeded the ecotoxicity permit limitations (TU 1 or TU 2) showed more than 2 times higher than that of direct effluent samples. However, effluent toxicity of Wastewater Treatment Plants (WTPs) indicated less than TU 1 regardless of influent toxicity. From this results, treatment process was thought to have a good efficiency. WTP Salinity was very similar between influent and effluent. This trend could be reconfirmed by the component ratio of ion concentration between them and $Na^+$, $SO_4^{2-}$, $C^-$ lions which have a greater percentage than other ions. In addition, in case of high salinity, toxicity value also showed high level. To judge from above results, indirect effluents which were exempted from application of ecotoxicity standards, may need a new effluent limitations regardless of the treatment efficiency of WTP. According to circumstances, effective countermeasure may need to restrain the discharge of salinity-contained effluents which came from indirect-effluent factories. Test duration comparative study indicated that 48 h results were higher toxicity (exceeding rate of ecotoxicity criteria) than 24 h by the 5 to 5.4 percentage. 24 h test duration seemed to be useful in case of rapid detection, whereas 48 h test method could be applied for reinforcement of ecotoxicity regulatory system.

Comparative Toxicity of some Pesticides to the Predatory Mites, Neoseiuius fallacis Carman (Acari: Phytoseiidae) (팔라시스이리응애에 대한 농약의 독성)

  • Kim, Dong-Hwan;Kim, Sang-Soo;Kim, Kwang-Sik;Hyun, Jae-Wook
    • Korean journal of applied entomology
    • /
    • v.45 no.2 s.143
    • /
    • pp.179-188
    • /
    • 2006
  • The toxicities of 37 commercial pesticides for citrus pests were evaluated to H, fallacis. Eight fungicides (difenoconazole, imibenconazole, azoxystrobin, dithianon, fluazinam, procymidon, streptomycin, tribasic copper sulfate), three insecticides (dichlovos, imidacloprid, thiamethoxam) and four acaricides (milbemectin, tetradifon, dicofol, spirodiclofen) had lower effect to the hatchability of eggs N. fallacis. Six fungicides (propineb, difenoconazole, imibenconazole, azoxystrobin, dithianon, procymidon) and three acaricides (bifenazate, tetradifon, spirodiclofen) showed lower contact toxicity to adult N. fallacis. The secondary toxicity of 26 pesticides to N. fallacis adult were evaluated. Two fungicides (fluazinam, streptomycin) and 3 acaricides (machine oil, cyhexatin, halfenprox) showed low toxicity when the prey (eggs of spider mite) was treated with pesticides.

Comparative In Vitro Biological Toxicity of Four Kinds of Air Pollution Particles

  • Shin, Han-Jae;Cho, Hyun Gi;Park, Chang Kyun;Park, Ki Hong;Lim, Heung Bin
    • Toxicological Research
    • /
    • v.33 no.4
    • /
    • pp.305-313
    • /
    • 2017
  • Accumulating epidemiological evidence indicates that exposure to fine air pollution particles (APPs) is associated with a variety of adverse health effects. However, the exact physiochemical properties and biological toxicities of fine APPs are still not well characterized. We collected four types of fine particle (FP) (diesel exhaust particles [DEPs], natural organic combustion [NOC] ash, synthetic organic combustion [SOC] ash, and yellow sand dust [YSD]) and investigated their physicochemical properties and in vitro biological toxicity. DEPs were almost entirely composed of ultrafine particles (UFPs), while the NOC, SOC, and YSD particles were a mixture of UFPs and FPs. The main elements in the DEPs, NOC ash, SOC ash, and YSD were black carbon, silicon, black carbon, and silicon, respectively. DEPs exhibited dose-dependent mutagenicity even at a low dose in Salmonella typhimurium TA 98 and 100 strains in an Ames test for genotoxicity. However, NOC, SOC, and YSD particles did not show any mutagenicity at high doses. The neutral red uptake assay to test cell viability revealed that DEPs showed dose-dependent potent cytotoxicity even at a low concentration. The toxicity of DEPs was relatively higher than that of NOC, SOC, and YSD particles. Therefore, these results indicate that among the four FPs, DEPs showed the highest in vitro biological toxicity. Additional comprehensive research studies such as chemical analysis and in vivo acute and chronic inhalation toxicity tests are necessary to determine and clarify the effects of this air contaminant on human health.

Biological Toxicity Changes of Mercaptoacetic Acid and Mercaptopropionic Acid Upon Coordination onto ZnS:Mn Nanocrystal

  • Kong, Hoon-Young;Hwang, Cheong-Soo;Byun, Jong-Hoe
    • Bulletin of the Korean Chemical Society
    • /
    • v.33 no.2
    • /
    • pp.657-662
    • /
    • 2012
  • Mercaptoacetic acid (MAA) and mercaptopropionic acid (MPA) capped ZnS:Mn nanocrystals were synthesized and their physical characteristics were examined by XRD, HR-TEM, EDXS, and FT-IR spectroscopy. The optical properties of the MPA capped ZnS:Mn nanocrystals dispersed in aqueous solution were also measured by UV/Vis and solution photoluminescence (PL) spectra, which showed a broad emission peak around 598 nm (orange light emissions) with calculated relative PL efficiency of 5.2%. Comparative toxicity evaluation of the uncoordinated ligands, MAA and MPA, with the corresponding ZnS:Mn nanocrystals revealed that the original ligands significantly suppressed the growth of wild type E. coli whereas the ligandcapped nanocrystals did not show significant toxic effects. The reduced cytotoxicity of the conjugated ZnS:Mn nanocrystals was also observed in NIH/3T3 mouse embryonic fibroblasts. These results imply that potential toxicities of the capping ligands can be neutralized on ZnS:Mn surface.

Comparative Study on the EC50 Value in Single and Mixtures of Dimethylformamide, Methyl Ethyl Ketone, and Toluene

  • Kim, Ki-Woong;Won, Yong Lim;Park, Dong Jin;Kim, Doh-Hee;Song, Kwan Young
    • Toxicological Research
    • /
    • v.30 no.3
    • /
    • pp.199-204
    • /
    • 2014
  • The aim of this research was to improve our understanding of human toxicity due to exposure to DMF, MEK, or TOL individually as compared to exposure to DMF-MEK or DMF-TOL mixtures, by comparing $EC_{50}$ values as well as the morphological changes in HepG2 cells treated with these substances. We found that there was marked cell necrosis in the groups treated with mixtures than in those treated with the compounds alone, and that the amount of cell death and the $EC_{50}$ value were more dependent on MEK and TOL than on DMF. Moreover, analysis of the changes in effective concentration curves revealed that MEK had an antagonistic effect on the human toxicity of DMF, whereas TOL had a synergistic effect. Accordingly, these results suggest that in workplaces involved in the manufacture of synthetic leather, mixtures of DMF and TOL should be avoided as much as possible in order to minimize environmental toxicity and protect the health of the workers.

Comparative Studies of Panax ginseng and Panax quinquefolium on TCDD-induced Toxicity in Rats

  • Wee Jae Joon;Choi Seung Hoon;Park Kyeong Mee;Kyung Jong Su;Kang Dae Young;Song Tae Won
    • Proceedings of the Ginseng society Conference
    • /
    • 2002.10a
    • /
    • pp.227-237
    • /
    • 2002
  • One prominent characteristic of2,3,7,8-tetrachlorodibenzop-dioxin (TCDD) toxicity in rats is a reduction of body weight accompanied by an altered serum lipid profile such as hyperlipidemia. A single administration of TCDD (50 ug/kg) resulted in a decrease of body weight and increase of serum cholesterol in rats. TCDD-induced weight loss and serum cholesterol elevation was reduced in rats administered with water extract (100 mg/kg) or saponin fraction (40 mg/kg) of Panax ginseng C.A.Meyer. In contrast, the administration of Panax quinquefolium did not inhibit the TCDD-induced weight loss and serum cholesterol elevation. Histological examinations of liver and testis revealed the administration of saponin fraction of Panax ginseng attenuated the TCDD-induced hispathologicallesions whereas the administration of saponin fraction of Panax quinquefolium did not. High performance liquid chromatographic analysis demonstrated high percentiles of ginsenoside Rg and ginsenoside $Rh_1$ were evident in saponin fraction of Panax ginseng. Results indicate that the protective effects of Panax ginseng, not Panax quinquefolium, on the TCDD-induced toxicity might be resulted from different compositions of saponins in Panax ginseng.

  • PDF

Stereotactic radiotherapy for early stage non-small cell lung cancer

  • Ricardi, Umberto;Badellino, Serena;Filippi, Andrea Riccardo
    • Radiation Oncology Journal
    • /
    • v.33 no.2
    • /
    • pp.57-65
    • /
    • 2015
  • Stereotactic body radiotherapy (SBRT) represents a consolidated treatment option for patients with medically inoperable early stage non-small cell lung cancer (NSCLC). The clinical evidence accumulated in the past decade supports its use as an alternative to surgery with comparable survival outcomes. Due to its limited toxicity, SBRT is also applicable to elderly patients with very poor baseline pulmonary function or other severe comorbidities. Recent comparative studies in operable patients raised the issue of the possible use of SBRT also for this subgroup, with quite promising results that still should be fully confirmed by prospective trials with long-term follow-up. Aim of this review is to summarize and discuss the major studies conducted over the years on SBRT and to provide data on the efficacy and toxicity of this radiotherapy technique for stage I NSCLC. Technical aspects and quality of life related issues are also discussed, with the goal to provide information on the current role and limitations of SBRT in clinical practice.