The document discusses the relationship between dose and response for chemicals. It defines dose as the amount of a chemical administered, usually expressed per unit of body weight. The absorbed dose may be less than the administered dose due to incomplete transport across membranes. Response refers to the biological change or effect caused by a chemical. The severity of response depends on factors like the concentration of chemical at the tissue site, absorption and distribution rates, excretion and detoxification abilities, and an individual's tolerance and health state. A dose-response relationship demonstrates how the amount of a chemical influences the proportion of a population exhibiting an effect.

1. Dose Response Relationship
Dr. Asmita Daspute .
Assistant Professor,
Dept. of Environmental Science,
Sbes College Of Science Aurangabad.(Ms)

3. Dose
 Dose: Amount of chemical administered usually express per unit Body
weight.
 If the dose is administered into the stomach or applied on the skin or into
respiratory tract,
 Transport across the membranes may be incomplete and the absorbed
dose will not the be identical with the dose adminisered
 Estimation of Dose can be made from
 Measurement of environmental and Food concentration
 Food intake
 Inhalation rate
 Appropriate deposition and retention factors

4. Dose
 The Dose in the organ and Tissues of interest may be estimated-
 Administered Dose or Intake
 Measurement of the concentration in tissues and organ samples
 Measurement of the concentration in excreta or exhaled air.

5. Responce
 Response and effect are often used interchangeably to denote the biological change either
in individual or in a population.
 Effect – is biological change
 Response – proportion of a population that demonstrates a defined effect. Or
 Incidence rate of effect .
 e,.g.- LD50 value may be described as the dose expected to cause a 50% response in a
population tested for lethal effect of a chemical

7. Response to chemicals
 Concentration at the site of respective tissue
 Rate of absorption
 Distribution
 Excretion and
 Detoxification of a chemicals
 Tolerance and hypersensitivity to a chemical
 Genetic factors
 State of health