A comprehensive presentation on Food Toxicants to facilitate easy-learning for medical , dental , pharmacology and biotechnology students.

1. Dr. Rohini C Sane
Food Toxicants

2. Food toxins and Additives
• Naturally occurring harmful compounds :
• Pesticides and packaging materials :are to food material
through inadvertent contamination.
• Additives/ compounds added to food : as preservatives or to
add colour ,favour or texture. some of additives may be harmful.
• Consumption of fresh and unprocessed foods are advised in
order to minimise the intake of natural toxins and additives.
Naturally occurring harmful compound source of food
Neurotoxins shellfishs,mushrooms
Goiterogens plants from cabbage family
inhibitors of collagen formation some bean compounds

3. Naturally occurring food Toxicants
Naturally occurring
toxicants in foods
Food source Toxic effects
Beta- oxaylaminoalanine
(BOAA)
consumption large
quantities Lathyrus
sativus (kesary dal) or
other lathyrus species
Lathyrism(crippling disease
accompanied by paralysis of leg
muscles/lower limps, painful
joints)
Hypoglycin A and
Hypoglycin B
(unusual amino acids)
partially cooked Ackee
fruit (to be consumed
only after 20 minutes
boiling)
vomiting, drowsiness ,
Hypoglycaemia leading to
convulsions,coma and death
Goitrogen(1,5- vinyl -2-thio-
oxazolidone)
Cabbage and turnip goitre
Goitrogen
(thioglycosides)
Rapseed, mustard goitre
Goitrogen
(polyphenolic glycosides)
red skin of groundnuts
and almonds
goitre
Biogenic amines :Serotonin,
histamine, epinephrine,
tyramine
intake of plantains(green ,
ripe) in large quantity
endomyocardial fibrosis( due to
inactivation mono-amino
oxidase),hypertension
Sanguinarine from
Argemone seeds
Rap seeds getting mixed
with seeds of Argemone
grow as weeds during
harvest
epidemic dropsy in human

4. Toxic effects of some metals as food contaminants
Metals/chemicals source for food
contamination
Toxic effects
Arsenic
(Arsenic oxide)
food sprayed by lead
arsenate(rat poison)
chills ,cramps ,paralysis
Barium
(Barium carbonate)
food contaminated with
rat poison
muscular twitching , convulsions
Cadmium
Fruit juices and soft
drinks
excessive salivation, liver and
kidney damage , prostrate cancer
Cobalt beer cardiac failure
Lead some processed foods paralysis ,soft tissue damage
e.g. kidney ,brain ,liver
Mercury seed grains treated with
Mercury fungicides
paralysis ,soft tissue damage
e.g.kidney ,brain ,liver
Tin canned foods colic ,vomiting
Zinc food stored in galvanised
ironware
Dizziness, vomiting
Copper
Acidic food in contact
tamished copper ware
vomiting ,diarrhoea ,
abdominal pain

5. Toxic effects of some Chemicals as food contaminants
chemical source for food contamination Toxic effects
Pesticides
(e.g.DDT,Malathion,
BHC)
all types of food contaminated
with pesticides
damage to liver ,kidney,
brain, nerves leading to
death
Antibiotics
meat from animals fed with
antibiotics
drug resistance ,
hardening of arteries ,heart
disease
Diethyl stilbestrol
present in meat of stilbestrol
fed animals and birds
Carcinogenesis,leukemia

6. Micro-organisms as Food Toxicants
Harmful micro-organisms contaminate :
1.the raw food such as meat, fish, milk purchased from the
market.
2.are destroyed during cooking or processing but some of the
micro-organisms survive due to insufficient heat.
3.especially infect food grains and oil seeds when stored in
humid atmosphere causing serious illness.
Parasitic infections: the contaminated foods transmit some
parasitic diseases e.g. amoebiasis, ascariasis, and hookworm
when vegetables grown on sewage water and are consumed in
raw conditions.

7. Pathogenic bacterial micro-organisms as food toxicants
Pathogenic
organism
mode of contamination of
food
Toxic effects
Salomonella
infection transmitted mainly
by processed animal foods
vomiting, diarrhoea , rise of
body temperature
Staphylococci
exotoxins produced by
organism in precooked
animal foods
vomiting, diarrhoea ,
abdominal pain
Streptococci
sore throat producing
organisms
vomiting, diarrhoea ,
abdominal pain
Shigella
Flies are carriers of bacteria .
When cooked food are kept
exposed and get
contaminated. Raw milk to
which contaminated water
added.
Bacillary dysentery, loose
motions with mucus and
blood ,abdominal pain,

8. Type of Fungus
source of food
contamination
toxic effects
Aspergillus flavus
cotton seeds , cereals,
moist ground nuts,
soyabean ,maize
aflatoxins develop cancer,
cirrhosis ,
Penicillium
islandicum
Rice on storage
yellow discolouration of rice,
toxic symptoms in human
beings
Claviceps purpurea
(Ergot)
toxic alkaloids produced
a fungus causing
contamination Rye and
millet during cultivation
nausea ,vomiting,diarrhoea,
giddiness,severe burning
sensation in extremities,
painful cramps in limbs,
gangrene in finger and
toes,depression,convulsions ,
weakness
Fusarium and
Cladosporium
fungus infects millets
when left unharvested in
field during winter
acute enteritis , nausea ,
vomiting ,leukopenia,anaemia,a
granulocytosis,petechial
hemorrhages,necrotic ulcers of
skin
Fungal micro-organisms as food Toxicants

9. Thank You