• Journal of Ecology and Environment
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• v.41 no.11
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• pp.318-327
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• 2017

Background: A typical sewage treatment plant is designed for organic and nutrient removal from municipal sewage water and not targeted to eliminate micropollutants such as pesticides, pharmaceuticals, and nano-sized metals which become a big concern for sustainable human and ecological system and are mainly discharged from sewage treatment plant. Therefore, despite contaminant removal by wastewater treatment processes, there are still remaining environmental risks by untreated pollutants in STP (sewage treatment plant) effluents. This study performed aquatic toxicity tests of raw wastewater and treated effluents in two sewage treatment plants to evaluate toxicity reduction by wastewater treatment process and analyze concentration of contaminants to reveal potential toxic factors in STP effluents. Methods: Water samples were collected from each treatment steps of two STPs, and acute and chronic toxicity tests were conducted following USEPA (United States Environmental Protection Agency) and OECD (Organization for Economic Cooperation and Development) guidelines. Endpoints were immobility for mortality and reproduction effect for estrogenicity. Results: Acute $EC_{50}s$ (median effective concentration) of influents for Seungki (SK) and Jungnang (JN) STPs are $54.13{\pm}32.64%$ and $30.38{\pm}24.96%$, respectively, and reduced to $96.49{\pm}7.84%$ and 100%. Acute toxicity reduction was clearly correlated with SS (suspended solids) concentration because of filter feeding characteristics of test organisms. Chronic toxicity tests revealed that lethal effect was reduced and low concentration of influents showed higher number of neonates. However, toxicity reduction was not related to nutrient removal. Fecundity effect positively increased in treated wastewater compared to that in raw wastewater, and no significant differences were observed compared to the control group in JN final effluent implying potential effects of estrogenic compounds in the STP effluents. Conclusions: Conventional wastewater treatment process reduced some organics and nutritional compounds from wastewater, and it results in toxicity reduction in lethal effect and positive reproductive effect but not showing correlation. Unknown estrogenic compounds could be a reason causing the increase of brood size. This study suggests that pharmaceutical residues and nanoparticles in STP effluents are one of the major micropollutants and underline as one of estrogenic effect factors.

• Biomedical Science Letters
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• v.22 no.2
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• pp.46-52
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• 2016

Salicornia herbacea L. (S. herbacea) is an annual herbaceous plant of Chenopodiaceae. It grows in groups on the coast or mud flat of Korea is known to be rich in minerals. S. herbacea has potent anti-cancer, antioxidant, anti-obesity, bowel function improvement. However, pharmacological mechanisms of S. herbacea extract (SHE) remain poorly understood. The aim of this study was to investigate the potential acute toxicity of SHE in ICR mice administered a single oral dose of 0, 500, 1,000, and 2,000 mg/kg by gavage. After administration of the extract, signs of toxicity were observed every day for 14 days. No mortality, abnormal clinical signs, body weight, organ weight or pathological changes were observed compared to a control group, and there were no differences in the body weights of the control and treatment groups. Biological serum activities and histological tests were not significantly changed in the treatment group compared to the control group. Especially, treatment of SHE was significantly decreased of total cholesterol and triglyceride levels. These results indicated that a single oral administration of SHE does not exerts any toxic effects at a dose of 2,000 mg/kg and that the $LD_{50}$ of SHE is greater than 2,000 mg/kg. Accordingly, SHE appears to have potential in various functional agents of foods, without toxicity.

• The Korea Journal of Herbology
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• v.22 no.2
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• pp.13-16
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• 2007

Objectives : Palmul-tang(Bawu-tang) has been traditionally prescribed a medicine as a restorative. Methods : In this study, we investigated the acute toxicity about water-extracted PalMul-tang(Bawu-tang). Twenty-five mice completed 14 days of oral Palmul-tang(Bawu-tang) at the respective doses of 0(control group), 2560, 3200, 4000 and 5000mg/kg. Results : We observed survival rates, general toxicity, change of body weight, and autopsy. Conclusions : To be confirmed the data for the toxicity and safety problems of oriental medicine prescription. Compared with the control group, we could not find any toxic alteration in all treated groups (2560, 3200, 4000 and 5000mg/kg). In conclusion, LD50 of Palmul-tang(Bawu-tang) was over 5000mg/kg and it is very safe to ICR mice.

• Journal of Environmental Science International
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• v.16 no.1
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• pp.55-63
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• 2007

There are concerns that chemical residues could harm the consumer on the environment, although 50 to 80% of the crops would be destroyed by pests and others without agrochemicals. Environmental fate and ecotoxicity studies are usually carried out to assess the impact on the human and the environment. A comparision of the Daphnia magnia and Simocephalus mixtus toxicity was performed to study the relative sensitivities and discrimination abilities to agriculture chemicals. The species of Simocephalus mixtus was more sensitive to agriculture chemicals than Daphnia magnia. Simocephalus mixtus was approved to be a water flea in determining insecticide and pesticide toxicity by heart-beat rate in a consistency and repeatability. The order of acute toxicity to water flea Daphnia magnia for ecotoxicity test was carbaryl>benomyl>amtirole with both Daphnia magnia and Simocephalus mixtus. The heartbeat pattern after the exposure to agrochemicals was different from that of exposure to heavy metals. Agrochemical leathal concentration test with heartbeat rate measurement was found to be more appropriate than inhibition concentration test with respect to toxicological endpoint.

• Journal of Korean Society on Water Environment
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• v.30 no.6
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• pp.632-637
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• 2014

Proficiency testing by interlaboratory comparisons is used to determine the performance of individual laboratories. In order to verify the quality of acute toxicity testing with Daphnia magna, National Institute of Environmental Research in South Korea is regularly organizing interlaboratory comparisons to estimate the analytical accuracy of different laboratories. Total 58 laboratories located in South Korea took part in interlaboratory proficiency testing scheme with three proficiency testing samples. TU(Toxic Unit) values of each laboratory were determined and robust z-score was calculated in order to evaluate the proficiency levels. Based on the robust z-score classification, 74% of the participant laboratories showed a satisfactory performance (43 laboratories). The main reason of 'unsatisfactory' performance seemed to be considered that the unsuitable management of test organism incubation system and the lack of experience on the identification of the test organism condition by effect of toxicity.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.5
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• pp.1192-1195
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• 2008

Sipjeondaebo-tang has been traditionally prescribed a medicine as a restorative. In this study, we investigated the acute toxicity about water-extracted Sipjeondaebo-tang. Thirty rats completed 14 days of oral Sipjeondaebo-tang at the respective doses of 0(control group), 2000 and 5000 mg/kg. We observed survival rates, general toxicity, change of body weight and autopsy. To be confirmed the data for the toxicity and safety problems of oriental medicine prescription. Compared with the control group, we could not find any toxic alteration in all treated groups (2000 and 5000 mg/kg). LD50 of Sipjeondaebo-tang was over 5000 mg/kg and it is very safe to SD rats.

• Journal of Korean Society on Water Environment
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• v.20 no.3
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• pp.265-268
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• 2004

Larva of Carassius auratus and Pungtungia herzi were exposed to mercury ($HgCl_2$), lead ($PbCl_2$) and copper ($CuSO_4$) to determine acute toxicity. The toxicity tests were conducted triplicate and the $LC_{50}$ values (24, 48, 72 and 96 hours) were determined for two species. Data obtained from the toxicity tests were evaluated using the probit analysis. Although sensitivities of two species to mercury were relatively similar, C. auratus was more susceptible than P. herzi to the exposure of lead but P. herzi was more sensitive than C. auratus on copper. The sensitivity on three metals tested may be ranked in the following order from highest to lowest toxicity on larval stage of these fish: mercury > copper > lead. It is suggested that acute toxic test at the larval stage of C. auratus and P. herzi, indigenous species in Asia area, is an important part of the ecotoxicological assessment of some heavy metals.

• Toxicological Research
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• v.25 no.3
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• pp.132-139
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• 2009

The toxicity test of ammonium persulfate was conducted to ensure of its potential toxic effects according to the single-dose acute oral toxicity study (OECD Guideline 423) and 90-day repeated dose sub-chronic oral toxicity study guideline (OECD Guideline 408) for establishing national chemical management system, and matching in the Globally Harmonized Classification System (GHS) category. In acute oral toxicity study, pasty stool, perineal contamination and temporary body weight decrease were observed after dosing 1st and 2nd challenge (300 mg/kg body weight). All test animals were dead within 6 hours after dosing at 3rd challenge (2000 mg/kg body weight). Therefore, the GHS class of test substance is considered class 4. In sub-chronic toxicity study, body weight changes, food consumptions, hematological, biochemical and pathological examination did not show any noticeable and significant differences between the administered (5, 20, 80 mg/kg body weight) and control (vehicle only) group animals. Based on these results, the no observed adverse effect level (NOAEL) is considered above 80 mg/kg body weight.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.28 no.2
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• pp.175-189
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• 2018

Objectives: In this study, we analyze statistics on industrial accidents caused by chemical skin contact and provide skin toxicity hazard information on the related domestic system and circulation volumes. Methods and Results: We analyzed occupational fatalities and skin diseases caused by chemical leaks and contact from 2007 to 2016(10 years) and surveyed data on occupational skin diseases using the 2014 work environment survey data. The NIOSH Skin Notation Profiles for 57 chemical substances, which are provided to prevent occupational skin diseases, were searched and hazard information on skin contact with chemical substances was classified. In order to identify skin toxicity information among domestically distributed and legally regulated substances and to investigate skin-toxic substances, MSDS basic data on 19,740 chemical substances provided on the homepage of Korea Occupational Safety & Health Agency were searched. Acute toxicity(dermal) category 1-4 substances totaled 1,020, and the number of chemical substances classified as category 1 and 2 substances were 135 and 137, respectively. In the chemical substances prescribed by the Ministry of Employment and Labor, 173 substances were classified into acute toxicity(dermal) categories 1-4, 58 of which correspond to category 1 or 2. Conclusions: Within the present range of industrial accidents, the proportion of skin diseases due to contact with chemicals is not high. However, there is always a risk of occupational skin diseases due to increasing chemicals and due to the use of new chemicals. It is hoped that this information will be used by workplace safety and health officials and health and safety experts to prevent acute toxity(dermal) due to chemical skin contact.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.4 no.1
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• pp.49-62
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• 2023

Phthalates are animal carcinogens. Potassium hydrogen phthalate (KHP), which has the least complicated structure among phthalates, is used for the analysis of total organic carbon and formaldehyde. However, its toxicity has not been confirmed. A 24-hour acute toxicity test was performed using Daphnia magna, a water flea used to evaluate aquatic toxicity owing to its high sensitivity. The lowest observed effect concentration of KHP was found to be 240 mg/L. The effects of phosphorus, nitrogen, and Cr(6+), which are able to be discharged along with KHP, were also confirmed using tests. At 240 mg/L KHP, toxicity increased as phosphorus, nitrogen, and Cr(6+) increased. In addition, tests were performed to confirm the half maximal effective concentration of KHP. Through 10 test repetitions, the average ecotoxicity value was found to be 0.3, the average half maximal effective concentration was 327.75 mg/L, and the coefficient of variation (%) was 3.16%; because the latter value is lower than 25%, which is what is generally suggested for the water pollution standard method, the reproducibility of the tests is sufficient to replace the existing standard reference toxicity test that uses potassium dichromate. In addition, the half maximum effective concentration of potassium hydrogen phthalate is approximately 218 times more than that of potassium dichromate; therefore, toxicity is relatively low. In conclusion, KHP is a feasible alternative to the highly toxic potassium dichromate for performing the standard reference toxicity test.