What factors contribute to the effect an environmental toxin has on the human body?

There are several factors that can contribute to the effect an environmental toxin has on the human body. They are:

- Form and innate chemical activity

- Dosage, especially dose-time relationship

- Exposure route

- Species

- Life stage, such as infant, young adult, or elderly adult

- Gender

- Ability to be absorbed

- Metabolism

- Distribution within the body

- Excretion

- Health of the individual, including organ function and pregnancy, which involves physiological changes that could influence toxicity

- Nutritional status

- Presence of other chemicals

- Circadian rhythms (the time of day a drug or other substance is administered)