All Flashcards
What are the steps in LD50/LC50 testing?
Animal testing, dose/concentration exposure, observation, and calculation.
What are the general steps of an LD50 test?
Animal testing, dose/concentration exposure, observation, calculation.
What does a low LD50 value indicate?
A lower LD50 value means a substance is more toxic.
What is the purpose of studying LD50s?
To compare toxicity, assess risk, guide regulation, and identify hazards.
Why is it important to consider the route of exposure when interpreting LD50 values?
Toxicity can vary significantly depending on whether a substance is ingested, inhaled, or absorbed through the skin.
What are the limitations of using LD50 values alone to assess risk?
LD50 values only measure acute toxicity and don't predict long-term effects or the effects of chemical mixtures.
Why is animal data not directly applied to humans?
Significant differences exist in how different species respond to chemicals.
What is the primary use of LD50/LC50 values?
To determine acute toxicity.
Why is the history of LD50 important?
J.W. Trevan's work provided a standardized way to measure and compare chemical toxicity.
What is the significance of NOAEL?
It represents the highest dose of a substance that does not cause any observable adverse effects.
What is the use of the ED50 value?
It represents the dose at which 50% of the population shows a specific effect, whether good or bad.
What is the relationship between LD50 and toxicity?
The lower the LD50, the more toxic the substance.