NURSING ANM AND GNM

NURSING EXAM QUESTIONS

TOXICOLOGY

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
Amount of a toxic material per unit of body weight of test animals that kills half the test population in a certain time
A
risk assessment
B
risk management
C
LD50
D
LD60
Explanation: 

Detailed explanation-1: -LD50 is the amount of a material, given all at once, which causes the death of 50% (one half) of a group of test animals. The LD50 is one way to measure the short-term poisoning potential (acute toxicity) of a material. Toxicologists can use many kinds of animals but most often testing is done with rats and mice.

Detailed explanation-2: -The median lethal dose (or LD50) is defined as the dose of a test substance that is lethal for 50% of the animals in a dose group. LD50 values have been used to compare relative acute hazards of industrial chemicals, especially when no other toxicology data are available for the chemicals.

Detailed explanation-3: -There is an inverse relationship between product toxicity and LD50 value. Products with lower LD50 values are more hazardous and pose a greater risk than products with higher LD50 values (Figure 1). For example, product A with an LD50 = 400 mg/kg is more toxic than product B with an LD50 = 600 mg/kg.

Detailed explanation-4: -An LD50 or 50% Lethal Dose value is the amount of a solid or liquid material that it takes to kill 50% of test animals (for example, mice or rats) in one dose. It is also called the median lethal dose. This is closely related to the LDLo value which is the lowest dosage reported to have killed animals or humans.

There is 1 question to complete.