• Title/Summary/Keyword: Toxicodynamic

Search Result 3, Processing Time 0.017 seconds

Toxicokinetic and Toxicodynamic Models for Ecological Risk Assessment (생태위해성 평가를 위한 독성동태학 및 독성역학 모델)

  • Lee, Jong-Hyeon
    • Environmental Analysis Health and Toxicology
    • /
    • v.24 no.2
    • /
    • pp.79-93
    • /
    • 2009
  • 오염물질에 대한 생태위해성평가(ecological risk assessment)를 위해서는 노출평가(exposure assessment)와 함께 생물영향에 대한 평가(effect assessment)를 수행해야 한다. 노출평가의 경우는 지화학적 과정에 대한 이해를 바탕으로 환경농도를 예측하기 위한 화학평형모델이나 다매체환경거동모델 등 다양한 평가 및 예측모델을 활용해 왔다. 이와 달리 생물영향평가는 실험실 조건에서 제한된 독성자료를 대상으로 외부노출농도에 기반한 농도-반응관계를 통계적 방법을 통해서 추정하는 '경험적 모델(empirical model)'에 주로 의존해 왔다. 최근에 와서 생체 내 잔류량을 기반으로 농도-시간-반응관계를 기술하고 예측하는 독성동태학 및 독성역학 모델(toxicokinetic-toxicodynamic model)과 같은 독성작용에 기반한 모델(processbased model)들이 개발되어 활용되고 있다. 본 논문에서는 여러 종류의 독성동태학 및 독성역학 모델을 소개하고, 이를 통계적 추론에 기반한 전통적인 독성학 모델과 비교하였다. 서로 다른 종류의 독성동태학 및 독성역학 모델로부터 도출된 노출농도-시간 -반응관계식을 비교하고, 동일 독성기작을 보이는 오염물질 그룹 내에서 미측정 오염물질의 독성을 예측할 수 있게 해주는 구조-활성관계(Quantitative Structure-Activity Relationship, QSAR) 모델을 여러 독성동태 및 독성역학모델로부터 유도하였다. 마지막으로 독성동태학 및 독성역학 파라미터를 추정하기 위한 실험계획을 제안하였고, 앞으로 독성동태학 및 독성역학 모델을 생태계 위해성평가에 활용하기 위해서 해결해야 될 연구과제를 검토하였다.

Pharmalogical Effects and Toxicity of Licorice (감초의 효능과 독성)

  • 박영철;이선동;이인선
    • Toxicological Research
    • /
    • v.18 no.3
    • /
    • pp.301-309
    • /
    • 2002
  • Licorice has been wed in clinical medicine for thousands of years. However it is only in recent times that we have been able to employ scientific methods to prove its efficacy and to give us a better understanding of its mechanism of action. One of important mechanisms for its efficacy is related to mineralocorticoid activity increased by glycyrrhizic acid, the active ingredient in licorice. Also the main undesirable side-effects of Licorice relate to is mineralocorticoid activity resulting in a state of apparent mineralocorticoid excess (AME). These therapeutic and undesirable effects are explained by the inhibition of 11-$\beta$-hydroxysteroid dehydrogenase (11-$\beta$-HSD) activity. Recently, the reduction of serum testosterone in men by licorice was reported which would have important health implications in the context of fertility and sexual dysfunction. Here, health implication of licorice were reviewed In term of its pharmacodynamic and toxicodynamic mechanism.

Binary Mixture Toxicity of AROCLOR 1248, Oleic Acid, and Elemental Sulfur to Vibrio fischeri Luminescence

  • Kalciene, Virginija;Dabkeviciene, Daiva;Cetkauskaite, Anolda
    • Journal of Environmental Science International
    • /
    • v.24 no.11
    • /
    • pp.1541-1546
    • /
    • 2015
  • The objective of this research was to evaluate the toxicity of the industial xenobiotic Aroclor 1248 (A) and natural origin substances~elemental sulfur (S80) and oleic acid (OA) and their binary mixtures to V. fischeri bioluminescence during the prolonged exposure time (up to 60 min). The bioluminescence quenching test was used to determine the toxic effects. Full factorial experiment design and multiple regression analysis and the comparison of binary mixture effect with the sum of effects of individual chemicals were used for the evaluation of combined effects of toxicants. The analysis of general trend of mixture toxicity to bioluminescence showed that mixture toxic effects were reversible up to 60 min. Data analysis revealed different joint effects, which were depended on mixture composition. S80 enhanced toxic effect of A and acted additively with synergistic interaction. Hydrophobic OA in mixture with A acted antagonistically and in mixture with sulfur caused an additive effect with antagonistic component of interaction. It was concluded that low concentrations of natural toxic substances present in environmental samples as mixtures of chemicals can define the toxicodynamic character of industrial xenobiotics.