What is a toxicological endpoint, the type of toxicological endpoint, its importance and the importance of the data generated from it.

1. Toxicology Endpoints
Teke Efeti Mary SC19P013
Zih Felicitas Enam SC19P274
Arreyetta Bawak Augustine SC19P008
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2. Learning objectives
Define Toxicology Endpoints
Some predictions of Toxicological Endpoints
Types of Toxicological Endpoints:
- Acute Endpoints
- Chronic Endpoints
How toxicological Endpoints are carried out:
- In Vitro Endpoints
- In Vivo Endpoints
Use of Toxicological Endpoint Data
Importance of Toxicology Endpoints
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3. Toxicological Endpoint
Toxicology endpoint is the result of a study
conducted to determine how dangerous a
substance is (Alt, 2017).
The Data collected from such studies are used
to report the relative toxicities of compounds
to various regulatory agencies and
environmental compliance groups (Alt, 2017).
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4. Predictions of Toxicological
Endpoints
Toxicology endpoints can be used to
predict:
- Mortality
- Behavior
- Reproductive status
- Physiological and biochemical changes
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(Alt, 2017).

5. Types of Toxicological Endpoints
Toxicology endpoints could be divided
into two:
- ACUTE TOXICITY ENDPOINTS
- CHRONIC TOXICITY ENDPOINTS
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(Alt, 2017).

6. ACUTE TOXICITY ENDPOINTS
This requires that test materials be given to
animals for a short period of time (about a
week), usually as a single exposure (HSE,
2017).
There are three acute toxicity endpoints:
- ACUTE LETHAL TOXICITY
- ACUTE DERMAL IRRITATION/
CORROSION
- ACUTE OCULAR IRRITATION
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7. ACUTE TOXICITY ENDPOINTS
ACUTE LETHAL TOXICITY
The goals of acute lethal toxicity testing include the
following:
- Determine susceptible population and species.
- Identify target organs or systems.
- Define the degree of hazard that may result after exposure to
a test substance.
- Provide information to clinicians that will enable them
predict, diagnose and/or provide treatments for acute
exposures.
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(Alt, 2017).

8. ACUTE TOXICITY ENDPOINTS
ACUTE DERMAL CORROSION AND IRRITATION
The goal of dermal corrosion is to check or determine the
effect of the substance after exposure to the skin (for
example bleaching creams) (Alt, 2017).
ACUTE OCULAR TESTING
The goal is to assess the risk when materials enter the eyes
especially for individuals who might become exposed
when accidental entry occurs through spraying, splashing
(for example, women who use cosmetics) (Alt, 2017).
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9. ACUTE TOXICITY ENDPOINTS
 With acute studies, a common endpoint is
an LD50 (lethal dose) which is the dose
of a compound required to kill half the
organisms in the study (Alt, 2017).
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10. CHRONIC TOXICITY ENDPOINT
It is longer in duration (more than a week)
and include endpoints such as reproduction,
long-term survival and growth (Alt, 2017).
Chronic studies are valuable because they
examine the effects of extremely low
concentration of compounds that may persist
in the environment for long periods of time (
for example DDT( Dichlorodiphenyl
trichloroethane))(W.H.O, 1979).
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11. Ways by which toxicological
endpoint could be carried out
Toxicology endpoints can be done in two
ways:
-In vitro Endpoints
-In vivo Endpoint
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(HSE, 2O17).

12. In vitro Endpoints
Scientist conduct in vitro studies in test
vessels. Endpoints of in vitro studies may
include changes in reproductive status or
hormone levels (HSE, 2O17).
In vitro studies are advantageous and often
considered more ethical, because they do not
use living animals but only living cells in
culture (HSE, 2O17).
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13. In vivo Endpoints
 It is conducted within living organisms.
 The advantage of in vivo studies is that
researchers can examine the effects of the
compound on the entire organism (HSE,
2O17).
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14. Toxic Endpoint Data uses
Toxicity endpoints are used to establish
toxicity thresholds, which are levels of a
compound below which adverse effects
are not seen (HSE, 2O17).
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15. Importance of Toxicological
Endpoints
To help companies that access compounds, to
assess how hazardous a compound is, before
release into the environment ( for example
pesticides).
Regulatory agencies ( for example
Environmental Protein Agency) require these
tests, to keep these materials at environmental
levels . That is, low enough to be considered
safe for plants and animals (HSE, 2O17).
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16. References
UK Health and Safety Executive:
Toxicological Endpoints Database.
AltTox: Alternative Toxicity Endpoints and
Tests.
World Health Organization. DDT and its
derivatives. Environmental Health Criteria.
Geneva, Switzerland, 1979; Vol. 9.
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