TOXICOLOGY BY Sir Kings
TOXICOLOGY 1
INTRODUCTION
During the past decades industrialization and agricultural development, paralleled with increased
health care have changed life in various ways. Average life expectancy rose, due to better control
of epidemics and infectious diseases. However, increased industrialization and agricultural
development were the chief cause of pollution that had profound influences on our lives. Man,
the other animals, & the plants in the modern world are increasingly being exposed to chemicals
of an enormous variety. Nearly everyone is at risk of toxic exposures to hazardous substances in
the ambient environment. In recent years, awareness of the problem of human & animal
exposure to potentially toxic chemicals in our environment has grown. So toxicology has a very
important role to play in modern society & consequently it is now growing rapidly as a new
subject.
Toxicology addresses a variety of questions. For example, in agriculture, toxicology determines
the possible health effects from exposure to pesticides or herbicides, or the effect of animal feed
additives, such as growth factors, on people. Toxicology is also used in laboratory experiments
on animals to establish dose-response relationships. Toxicology also deals with the way
chemicals and waste products affect the health of an individual.
What is toxicology?
The word toxicology is derived from two Greek words; toxikon, meaning poisonous substance
into which arrow heads were dipped and logos, meaning study.
Toxicology is the qualitative and quantitative study of the adverse or toxic effect of chemicals
and other anthropogenic materials or xenobiotics on organisms. It also deals with food and
cosmetics for public consumption both in alive or dead victims. It is the science of poison & its
scope has been enlarging. It is one of the multidisciplinary fields of science.
DEFINITION OF TERMS
• What is Toxicity? describes the degree to which a substance is poisonous or can cause
injury. It depends on a variety of factors: dose, duration and route of exposure. Toxicity
can also be defined as the ability of a chemical agent to cause injury. It is a qualitative
term which depends on the amount of chemical absorbed, severity of the exposure, dose
Copy right reserved @2023 Page 1
, TOXICOLOGY BY Sir Kings
& others. It can be acute (toxic event which occurs soon after acute or limited exposure),
or chronic (apply to an event which occurs many weeks, months or years after exposure).
• What is Toxic? This term relates to poisonous or deadly effects on the body by
inhalation (breathing), ingestion (eating), or absorption, or by direct contact with a
chemical.
• Toxicology - the study of poisons (the adverse effect of drugs/chemicals)
• Toxicologist - one who studies poisons, ie, the adverse effect of drugs/chemicals.
• Risk - the probability that an event will occur. Risk can also be defined as the expected
frequency of the occurrence of an undesirable effect arising from exposure to a chemical
or physical agent.
• Toxic substance - poisons
• Poison - any chemical substance which can cause harm
• Drug overdose - taking a harmful amount of a drug
• Toxin- a poison of natural origin. Toxin is usually used when talking about toxic
substances produced naturally. A toxin is any poisonous substance of microbial (bacteria
or other tiny plants or animals), vegetables, or synthetic origin that reacts with specific
cellular components to kill cells, alter growth or development, or kill the organism.
• Poison (Toxicant) - a chemical that may harm or kill an organism
• Hazard – is the likelihood that injury will occur in a given situation or setting: the
conditions of use and exposure are primary considerations.
• Acute exposure is a single exposure – or multiple exposures occurring over 1 or 2 days.
• Chronic exposure is multiple exposures continuing over a longer period of time.
• What is a Toxicant? A toxicant is any chemical that can injure or kill humans, animals,
or plants; a poison. The term “toxicant” is used when talking about toxic substances that
are produced by or are a by-product of human-made activities. For example, dioxin (2,3-
7,8-tetrachlorodibenzop-dioxin {TCDD}), produced as a by-product of certain
chlorinated chemicals, is a toxicant. On the other hand, arsenic, a toxic metal, may occur
as a natural of groundwater or may contaminate groundwater as a by-product of industrial
Copy right reserved @2023 Page 2
TOXICOLOGY 1
INTRODUCTION
During the past decades industrialization and agricultural development, paralleled with increased
health care have changed life in various ways. Average life expectancy rose, due to better control
of epidemics and infectious diseases. However, increased industrialization and agricultural
development were the chief cause of pollution that had profound influences on our lives. Man,
the other animals, & the plants in the modern world are increasingly being exposed to chemicals
of an enormous variety. Nearly everyone is at risk of toxic exposures to hazardous substances in
the ambient environment. In recent years, awareness of the problem of human & animal
exposure to potentially toxic chemicals in our environment has grown. So toxicology has a very
important role to play in modern society & consequently it is now growing rapidly as a new
subject.
Toxicology addresses a variety of questions. For example, in agriculture, toxicology determines
the possible health effects from exposure to pesticides or herbicides, or the effect of animal feed
additives, such as growth factors, on people. Toxicology is also used in laboratory experiments
on animals to establish dose-response relationships. Toxicology also deals with the way
chemicals and waste products affect the health of an individual.
What is toxicology?
The word toxicology is derived from two Greek words; toxikon, meaning poisonous substance
into which arrow heads were dipped and logos, meaning study.
Toxicology is the qualitative and quantitative study of the adverse or toxic effect of chemicals
and other anthropogenic materials or xenobiotics on organisms. It also deals with food and
cosmetics for public consumption both in alive or dead victims. It is the science of poison & its
scope has been enlarging. It is one of the multidisciplinary fields of science.
DEFINITION OF TERMS
• What is Toxicity? describes the degree to which a substance is poisonous or can cause
injury. It depends on a variety of factors: dose, duration and route of exposure. Toxicity
can also be defined as the ability of a chemical agent to cause injury. It is a qualitative
term which depends on the amount of chemical absorbed, severity of the exposure, dose
Copy right reserved @2023 Page 1
, TOXICOLOGY BY Sir Kings
& others. It can be acute (toxic event which occurs soon after acute or limited exposure),
or chronic (apply to an event which occurs many weeks, months or years after exposure).
• What is Toxic? This term relates to poisonous or deadly effects on the body by
inhalation (breathing), ingestion (eating), or absorption, or by direct contact with a
chemical.
• Toxicology - the study of poisons (the adverse effect of drugs/chemicals)
• Toxicologist - one who studies poisons, ie, the adverse effect of drugs/chemicals.
• Risk - the probability that an event will occur. Risk can also be defined as the expected
frequency of the occurrence of an undesirable effect arising from exposure to a chemical
or physical agent.
• Toxic substance - poisons
• Poison - any chemical substance which can cause harm
• Drug overdose - taking a harmful amount of a drug
• Toxin- a poison of natural origin. Toxin is usually used when talking about toxic
substances produced naturally. A toxin is any poisonous substance of microbial (bacteria
or other tiny plants or animals), vegetables, or synthetic origin that reacts with specific
cellular components to kill cells, alter growth or development, or kill the organism.
• Poison (Toxicant) - a chemical that may harm or kill an organism
• Hazard – is the likelihood that injury will occur in a given situation or setting: the
conditions of use and exposure are primary considerations.
• Acute exposure is a single exposure – or multiple exposures occurring over 1 or 2 days.
• Chronic exposure is multiple exposures continuing over a longer period of time.
• What is a Toxicant? A toxicant is any chemical that can injure or kill humans, animals,
or plants; a poison. The term “toxicant” is used when talking about toxic substances that
are produced by or are a by-product of human-made activities. For example, dioxin (2,3-
7,8-tetrachlorodibenzop-dioxin {TCDD}), produced as a by-product of certain
chlorinated chemicals, is a toxicant. On the other hand, arsenic, a toxic metal, may occur
as a natural of groundwater or may contaminate groundwater as a by-product of industrial
Copy right reserved @2023 Page 2
