The environmental stimuli, global civilization, technical advancements and lifestyle modifications have paved way for rising toxicants into the food industry, thus, making the food more unsafe for use. The only way to get oneself nourished appropriately is to stay aware of the routes of toxification.
2. Defining food safety & toxicology
Basic concepts of food safety and toxicology
Poison and toxins
Toxicity
Routes of toxicity
Dose response
Exposure
Translocation
Absorption & distribution
Excretion
Food toxicology
2
3. The term food safety describes all practices that
are used to keep our food safe. Food safety relies
on the joint efforts of everyone involved in our
food supply. All along the food chain, from
farmers and producers to retailers and caterers,
legislation and controls are in place to reduce
the risk of contamination, and personally we each
have a role to play as well.
(THE EUROPEAN FOOD INFORMATION
COUNCIL)
3
4. Food Safety refers to handling, preparing and storing
food in a way to best reduce the risk individuals
becoming sick from foodborne illnesses.
(AUSTRALIAN INSTITUTE OF FOOD SAFETY)
4
5. Access to sufficient amounts of safe and nutritious
food is key to sustaining life and promoting good
health.
Unsafe food containing harmful bacteria, viruses,
parasites or chemical substances, causes more than 200
diseases – ranging from diarrhoea to cancers.
An estimated 600 million – almost 1 in 10 people in
the world – fall ill after eating contaminated food and
420 000 die every year, resulting in the loss of 33
million healthy life years.
5
6. Children under 5 years of age carry 40% of the
foodborne disease burden, with 125 000 deaths every
year.
Diarrhoeal diseases are the most common illnesses
resulting from the consumption of contaminated food,
causing 550 million people to fall ill and 230 000
deaths every year.
Food safety, nutrition and food security are inextricably
linked. Unsafe food creates a vicious cycle of disease
and malnutrition, particularly affecting infants, young
children, elderly and the sick.
6
7. Foodborne diseases impede socioeconomic
development by straining health care systems, and
harming national economies, tourism and trade.
Food supply chains now cross multiple national
borders. Good collaboration between governments,
producers and consumers helps ensure food safety.
7
9. Food toxicology is concerned with assessing
the injurious effects on living systems of
chemicals present in foods. The chemical
agents can be man-made (e.g., pesticide
residues, food additives, contaminants
originating with processing machinery, or
packaging materials) or of natural origin
(e.g., microbial, animal or plant toxins).
They can, also be generated in the course of
preparing, processing, and preserving foods
(e.g., mutagens and carcinogens).
(University of California, food science and
technology)
9
10. •POISON is any solid, liquid or gas that
can interfere with life processes of cells
of organisms and can exert physiological
or psychological disorders.
•Some poisons can cause illness or
injury in very small amounts.
•Illness may occur very quickly after
exposure to a poison, or it may develop
over several years with long-term
exposure.
•Poisons are also referred to as
“TOXICANT”-any agent capable of
producing deleterious response in
biological system.
10
11. •A toxin is a poisonous substance produced
within living cells or organisms.
•Natural toxins are toxic compounds that
are naturally produced by living organisms.
These toxins are not harmful to the
organisms themselves but they may be toxic
to other creatures, including humans, when
eaten. These chemical compounds have
diverse structures and differ in biological
function and toxicity.
(WHO)
•For example, Venoms are toxins that are
injected by a bite (for example, from a
spider) or sting (for example, from a wasp)
to cause their effect.
11
12. Aquatic biotoxins such as algal toxins that can cause
diarrhea, vomiting, tingling, paralysis and other effects
in humans, other mammals or fish.
Cyanogenic glycosides are phytotoxins (toxic
chemicals produced by plants) which occur in at least
2000 plant species (used as food in some areas of the
world). n humans, the clinical signs of acute cyanide
intoxication can include: rapid respiration, drop in
blood pressure, dizziness, headache, stomach pains,
vomiting, diarrhoea, mental confusion, cyanosis with
twitching and convulsions followed by terminal coma.
12
13. Furocoumarins are present in many plants such
as parsnips (closely related to carrots and parsley),
celery roots, citrus plants (lemon, lime, grapefruit).
They can cause severe skin reactions under sunlight
(UVA exposure).
Lectins-Many types of beans contain toxins called
lectins, and kidney beans have the highest
concentrations – especially red kidney beans. As few as
4 or 5 raw beans can cause severe stomachache,
vomiting and diarrhoea.
Mycotoxins are naturally occurring toxic compounds
produced by certain types of moulds. Long term effects
on health of chronic mycotoxin exposure include the
induction of cancers and immune deficiency.
13
14. All solanacea plants, which include tomatoes,
potatoes, and eggplants, contain natural toxins called
solanines and chaconine. They can also cause bruising
on UV exposure.
Wild mushrooms may contain several toxins, such as
muscimol and muscarine, which can cause vomiting,
diarrhoea, confusion, visual disturbances, salivation,
and hallucinations.
14
15. Some natural toxins can be formed in food as defense
mechanisms of plants, through their infestation with toxin-
producing mould, or through ingestion by animals of toxin-
producing microorganisms.
Natural toxins can cause a variety of adverse health effects
and pose a serious health threat to both humans and
livestock. Some of these toxins are extremely potent.
Adverse health effects can be acute poisoning ranging from
allergic reactions to severe stomachache and diarrhoea, and
even death.
Long-term health consequences include effects on the
immune, reproductive or nervous systems, and also cancer.
15
16. not assume that if something is 'natural' it is
automatically safe;
throw away bruised, damaged or discolored food, and
in particular mouldy foods
throw away any food that does not smell or taste fresh,
or has an unusual taste; and
only eat mushrooms or other wild plants that have
definitively been identified as nonpoisonous.
16
17. TOXICITY…
Toxicity is the amount of a poison that under specific set
of conditions causes toxic effects or results in detrimental
biological changes.
17
18. Usually expressed as milligrams (mg) of toxicant/kg
body weight that will produce a defined biological
effect.
DOSAGE- the amount of toxicant per unit of body
weight is called dosage.
DOSE- the total amount of toxicant received by a
person is called dose.
LETHAL DOSE (LD)- the lowest dose that causes
death in living organism during period of observation
is called lethal dose.
e.g. 1% (LD1), 50% (LD50) or 100% (LD100).
18
19. There are 4 different routes
through which poisons or toxins
can make entry into the living
organisms:
1. INGESTION
2. INHALATION
3. DERMAL/TOPICAL
4. PARENTERAL
ADMINISTRATION
19
21. ADVERSE EFFECT OR RESPONSE:
Adverse effect or response of a toxin is any change from an
organism’s normal state that is irreversible atleast for a period of
time.
An adverse effect or response can be GRADED (producing
variations of damage) or it can be QUANTAL (all or none i.e.,
mortality or tumor development).
FACTORS AFFECTING THE ADVERSE RESPONSE:
Genetic variations
Gender
Age
Nutritional status
Overall health conditions
Shape, size & solubility of toxicant
Distribution and excretion of toxicant from the body
21
23. Any organism must be exposed to an agent before
there is a risk.
23
24. The amount of toxin entering into the body and its
frequency will determine the extent of toxicity.
Acute
toxicity will
result within
24 hrs if the
dose is high
enough.
Repeated
doses of toxin
over a period
of one month
will result in
subacute
toxicity.
When the
exposure
extends from
1-3 months,
it will result
in subchronic
toxicity.
Chronic
toxicity is
caused by
repeated
doses of toxin
over a period
of 3 months
or more.
24
25. Distribution or translocation of a toxicant is
via the bloodstream to reactive sites,
including storage depots. The liver receives
the portal circulation and is the organ most
commonly involved with intoxication (and
detoxification).
The primary objective of metabolism is to
make the chemical agents more water
soluble for easier excretion.
25
28. DISTRIBUTION is the process in which a chemical
agent translocates throughout the body.
The rate of distribution is usually rapid and is
determined by the blood flow and also, the chemical
characteristics of toxicant.
28
29. Routes of excretion of
toxicants:
1. Urinary excretion
(for water soluble
compounds)
2. Exhalation (for
volatile compounds)
3. Biliary excretion
(via faeces)
29