• 한국물환경학회지
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• 제25권1호
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• pp.90-95
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• 2009

This study investigates the oxidative degradation of N-nitrosodimethylamine (NDMA), a probable human carcinogen, by advanced oxidation process (i.e., UV process). The experiments were performed with various pH, initial concentration, UV intensity, and addition of $H_2O_2$ or $TiO_2$ on UV process. The results showed that the direct UV photolysis was the most effective treatment method. The lower pH, intial concentration and higher intensity of UV stimulated higher NDMA removal. However, addition of oxidant ($H_2O_2$, $TiO_2$) slows down photochemical treatment of NDMA since the oxidant can filter out the UV light and block it to reach the NDMA molecules. Dimethylamine (DMA) and nitrite were found to be a major byproduct from NDMA oxidation. To evaluate the chronic toxicity effects of UV-treated NDMA on the growth of microalgae, "Skeletonema costatum", was studied as long term experiments. Results demonstrated that after the 13 days exposure the chronic toxicity was decreased about 15% with application of UV process on NDMA degradation.

• 대한약침학회지
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• 제11권4호
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• pp.25-37
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• 2008

Purpose The purpose of this study was to investigate sub-chronic toxicity of scolopendrid pharmacopuncture in mouse and method of increasing output of scolopendrid pharmacopuncture. Methods In order to prove the clinical safety of scolopendrid pharmacopuncture during 90 days, We have observed the physical reaction(side effect) and clinical pathology test after scolopendrid pharmacopuncture treatment and investigated method of increasing Output of scolopendrid pharmacopuncture for 90%, 80%, 70% ethanol. Results In subchronic toxicity test, there was no significant sign in clinical sign, opthalmological values, body weights, hematological values and urinalysis values. And we could see that food consumptions and water consumptions increased significantly, albumin, triglycerides, GPT in blood chemical values and Liver, Testis(right) in organ weights changed significantly in some groups, compared with those in the S1 group. But these changes were observed within the scope of physiology. So there was no sign of toxication in subchronic toxicity test, and we can tell that NOAEL(No Observed Adverse Effect Level) is above 0.286mg/kg/day. And 70% ethanol solution of scolopendrid was yielded the most amount of substance. Conclusions This study demonstrates that scolopendrid pharmacopuncture is to treatment of safety for a long time and we can obtain much amount from 70% ethanol solution of scolopendrid.

• Ecology and Resilient Infrastructure
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• 제8권4호
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• pp.281-289
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• 2021

상업에서 사용되는 일회용 컵은 환경으로 유입되어 파편화되어 미세플라스틱 (MP)이 될 수 있다. 또한 MP는 수생 생물에게 섭식 될 수 있으며, 다양한 부작용을 미칠 수 있다. 본 연구는 일회용 컵에서 유래된 MP 조각이 물벼룩에게 미치는 급성 및 만성 독성을 평가했다. MP 조각은 33.18 ±7.76 ㎛ 크기의 PET (Polyethylene terephthalate) MP 조각으로 확인되었으며, 3종류의 첨가제 (1- Propanone. 1-phenyl-3-[2-(phenylmethoxy)phenyl]-, p-Xylene and ethylbenzene)가 함유되어 있는 것을 확인하였다. 48시간 급성 독성은 최고 농도의 PET MP (200 mg L^-1)에 노출된 물벼룩에서 20%의 유영저해 및 사망을 발견하였다. 21일 만성 독성은 5 mg L-1의 PET MP 조각에 노출된 D. magna에서 대조군과 비교하여 줄어든 생존율 (31%)과 번식 (52%)을 보여주었다. 더욱이 PET MP는 태어난 개체의 발달 이상을 (3.5%) 대조군 (0.3%)과 비교하여 유의하게 (p < 0.05) 증가시켰다. 이러한 결과는 MP 조각의 섭취에 의한 장 막힘과 더 긴 체류 시간 때문일 수 있다. 본 연구의 결과는 일회용 컵 (PET 폴리머)이 작은 크기의 MP 조각으로 단편화되면 수생 생물에 심각한 생태학적 위험을 제기할 수 있음을 시사하고 있다. 또한 MP 독성 및 첨가제에 대한 근본적인 독성 메커니즘을 확인하기 위해 추가 연구가 수행되어야 한다.

• 한국환경성돌연변이발암원학회:학술대회논문집
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• 한국환경성돌연변이발암원학회 2002년도 Molecular and Cellular Response to Toxic Substances
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• pp.148-148
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• 2002

• 한국독성학회:학술대회논문집
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• 한국독성학회 2002년도 Molecular and Cellular Response to Toxic Substances
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• pp.42-58
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• 2002

Acute Cd exposure produces hepatotoxicity, whereas chronic Cd exposure produces nephrotoxicity, hematotoxicity, immunotoxicity and bone damage. Previous experiments suggest that the low-molecular-weight, metal-binding protein metallothionein (MT) in liver protects against liver injury, but is responsible for the kidney injury observed after chronic Cd exposure.(omitted)

• 한국환경보건학회지
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• 제49권5호
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• pp.237-246
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• 2023

Background: Arsenic is a metalloid of public health significance due to its unique material properties and toxicity and the widespread pollution in the environment. Arsenic exists as inorganic arsenic and organic arsenic with distinct chemical properties. Its toxicity varies depending on the properties. Objectives: Although the carcinogenicity of arsenic has been identified, the various diseases that occur after acute and chronic exposure to arsenic are not yet clearly known. Methods: Research on the effects of chronic exposure to arsenic on human health was searched and the results were summarized. Results: It has been found that cancer occurs due to exposure to high concentrations of arsenic in areas with elevated exposure to arsenic, but research results have recently been presented on health effects caused by chronic exposure to low concentrations of arsenic. Cancers have also been identified to be related to inorganic arsenic, including skin cancer, lung cancer, and bladder cancer. Significant relationships with neurological diseases, cardiovascular diseases, and diabetes mellitus have been suggested as well. Conclusions: Our results suggest that it is necessary to evaluate the health impact on residents around abandoned metal mines and industrial complexes in South Korea.

• 한국환경과학회지
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• 제16권4호
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• pp.425-432
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• 2007

The water flea has been used as a test organism of toxicity test for surface water. Toxicity test with water flea is categorized into two parts. One is acute toxicity test with observing immobility and mortality and the other is chronic toxicity test determined by survival and reproduction of water flea. Heartbeat measurement of water flea was designed as a short-term toxicity test in this study. Direct measurement of heartbeat under microscope by aid of video camera gives and early diagnosis of mortality in short time. Therefore, the effects of measuring illumination, measuring time, and non-feeding during the test on heartbeat of water flea was evaluated to establish a new test approach. Test organisms used in this study are Daphnia magna, a well standardizes toxicity test organism, and Simocephalus mixtus, a newly refined organism $IC_{50}$ values of these test organism by heartbeat measurement were compared and discussed. It was found that toxicity test by heartbeat measurement was a reproducible, easy and simple method accomplished in a few hours.

• 농약과학회지
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• 제8권4호
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• pp.309-318
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• 2004

우리나라에서 널리 사용되고 있는 벼재배용 살충제인 carbosulfan과 phenthoate의 담수어에 미치는 급 만성적 영향을 알아보고자 송사리(Oryzias latipes, Medaka)에 대한 급성독성시험(Acute Toxicity Test)과 생육초기 독성시험(Early-life Stage Toxicity Test)을 실시하였다. 급성독성시험 결과 carbosulfan과 phenthoate의 송사리에 대한 96시간 $LC_{50}$은 0.102, 0.167 mg/L로 비슷한 감수성을 보였다. 생육초기 독성시험 결과 carbosulfan의 경우 부화율은 80%이상, 부화기간은 $9\sim10$일로 나타나 처리구간 유의성이 없었다. 처리농도 0.042 mg/L이상에서는 부화후 생존율이 통계적으로 유의한(p<0.05) 차이를 보였으며, 척추가 휘어지는 형태적으로 비정상적인 결과가 관찰되었다. 시험 종료후 생존한 송사리의 전장 및 체중 변화는 농도 상관성을 보였으며, 특히 0.017 mg/L이상에서는 대조구에 비해 유의한(p<0.05) 감소를 나타내었다. 따라서 이런 결과를 근거로 한 무영향농도(NOEC), 최저영향농도(LOEC), 그리고 최대허용농도(MATC)는 각각 0.0067, 0.017, 0.011 mg/L으로 산출하였다. phenthoate 처리구의 부화율과 부화기간은 처리 농도간 유의성이 없었으나, 부화후 생존율은 처리농도 0.076 mg/L 이상에서 유의한(p<0.05) 차이를 보였다. 또한 처리농도 0.076 mg/L 이상에서는 척추기형과 유영이상을 보이는 이상어가 나타났다. 그러나 시험 종료후 송사리 전장 및 체중의 변화는 통계적인 유의한 차이가 없었으며, 농도 상관성도 보이지 않았다. 따라서 이런 결과를 종합하여 NOEC, LOEC, 그리고 MATC는 각각 0.011, 0.029, 0.018 mg/L으로 결정되었다.

• The Korean Journal of Pain
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• 제18권2호
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• pp.133-137
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• 2005

Background: Cannabinoids have shown antinociceptive action. The aims of this study were to examine the effect of chronic infusion of a cannabinoids receptors agonist (WIN 55,212-2) for thermal nociception at the spinal level, and to also observe the development of toxicity. Methods: Male Sprague-Dawley rats were implanted with lumbar intrathecal catheters with the nociceptive response (withdrawal response latency) determined by exposing the plantar surface of the hindpaw to radiant heat. Initially, the effect of intrathecal WIN 55,212-2 was evaluated followed by the change in the effect at 1, 2, 3 and 4 weeks after repeated infusion. Finally, the histopathological findings were assessed 1 and 4 weeks following the infusion of WIN 55,212-2. Results: Intrathecal WIN 55,212-2 was found to produce a limited antinociception during the thermal test. %MPE of WIN 55,212-2 at 1, 2, 3, and 4 weeks after infusion was not different from each other. No abnormal pathological findings were observed following a chronic intrathecal infusion of WIN 55,212-2. Conclusions: WIN 55,212-2, a cannabinoids receptors agonist, may be useful in the management of thermal nociception, without changing the effectiveness or causing the toxicity following a chronic infusion at the spinal level.

• 한국수산과학회지
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• 제31권1호
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• pp.95-103
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• 1998

연안 및 천해에 서식하는 반부유성 갑각류인 곤쟁이, Neomysis awatschensis를 대상으로 수온별 PCB의 시험농도에 따른 생물검정, 성장, 호흡 및 질소배설 등을 측정하여 PCB의 영향으로 인한 생리적 변화를 알아보았다. 곤쟁이에 미치는 PCB의 96시간 후의 반수치사 농도 (96 hr.-$LC_50$)는 $10^{\circ}C$에서 28.7492ppb, $20^{\circ}C$에서는 10.6742 ppb였다. PCB의 만성농도에서 약 60일간 노출시킨 후 생존율은 $10^{\circ}C$의 경우, 0.5ppb에서 $85\%$, 1.0ppb에서 $80\%$ 였으며, 1.5ppb와 2.0ppb에서는 $75\%$를 나타내었으며, $20^{\circ}C$의 경우는 0.5ppb에서 $85\%$, 1.0ppb와 1.5ppb에서 $75\%$, 그리고 2.0ppb에서는 $65.0\%$를 나타내었다. PCB의 각 만성농도에 노출시킨 곤쟁이의 평균체장성장율은 $10^{\circ}C$의 경우 대조구의 경우 0.039mm10ay, PCB농도 2.0ppb에서는 0.036mm/day를 였으며, $20^{\circ}C$에서는 대조구에서 0.072mm/day, 2.0ppb에서 0.039mm/day를 나타내었다. PCB는 탈피간체장증가율에는 뚜렷한 영향을 미치지 않았으나 탈피기간에는 개체의 크기와 수온에 따라 영향을 나타내었다. 수온별 PCB의 각 실험농도에 노출시킨 곤쟁이의 호흡 및 질소배설량의 변화는 PCB 실험농도의 고수온구에서 높게 나타났다. 또한 섭이 및 동화효율은 $10^{\circ}C$와 $20^{\circ}C$에서 PCB농도의 증가에 따라 감소하는 경향을 나타내었다.