This document summarizes several naturally occurring chemicals in foods that can cause foodborne illnesses. It describes the symptoms caused by ciguatoxins from contaminated tropical fish, scombrotoxin from fish stored at improper temperatures, shellfish toxins from algae-contaminated shellfish, and mycotoxins produced by certain molds. It provides examples of foods that contain chemicals like amygdalin, ipomeamarone, furocoumarins, glycoalkaloids, lectins, trypsin, oxalic acid, cucurbitacins, cyanogenic glycosides, and goitrogens, and symptoms of ingesting these chemicals. Prevention methods focus on proper storage, cooking, and

1. Foodborne Illnesses Caused by
Naturally Occurring Chemicals

2. Food Allergens
Cause the immune system to overreact
• Symptoms: Hives, swelling of the lips,
tongue and mouth, difficulty in breathing,
vomitting, diarrhea and cramps.
• Common Food Allergens:
• Milk, soy, egg, fish, wheat protein,
shellfish, peanuts, chicken

3. Ciguatoxins
• Symptoms:
• intoxication caused by nausea, vomiting,
eating contaminated diarrhea, dizziness,
tropical reef fish. shortness of breath
• The toxin is found in • Common Foods
algae and then eaten by
reef fish, which is eaten Barracuda, mackerel,
by big fish such as snapper, triggerfish
barracuda, mahi mahi ,
bonito, jack fish, • Prevention : Toxin
snapper, in which the is not destroyed by
toxin is accumulated in cooking. Purchase sea
the flesh of these fishes. foods from
Reputable
supplier

4. Scombrotoxin
• called ‘histamine” poisoning, caused by
eating food high in a chemical compound
called “histamine” which produced by
certain bacteria.
• Leaving fish at room temperature usually
result in histamine production.

5. Scombrotoxin
• Symptoms : dizziness, burning
sensation, facial rash, shortness of Breath,
peppery taste in the mouth.
• Common Foods : tuna, anchovies, blue
fish, mackerel, amberjack, Dark meat fishes.
• Prevention : Purchase food from
reputable supplier, Store “fresh” sea food at
Temperature between 32⁰F (0⁰C)-39⁰F
• Do not accept seafood that is suspected
being thawed and Refrozen or temperature
abused.

6. Shellfish Toxin
• toxins are produced by certain algae called “
dinoflagellates” when eaten by certain
shellfish such as mussles, clams, oysters,
Scallop accumulate in their internal organs
and become
Toxic to humans.
• Common Foods : Mussel, clams, oysters,
scallop
• Prevention : Purchase shellfish from
reputable supplier

7. Mycotoxins
• Fungi are molds, yeast and mushrooms,
some of which are Causing food borne
illnesses. Molds and yeast can withstand
more
• extreme condition than bacteria
• Many mycotoxin have been shown to
cause cancer.
• “aflatoxin” is produced by certain mold

8. Amygdalin
• (kernel) of apricots and peaches, that
can turn into hydrogen cyanide in the
stomach causing discomfort and
illness.

9. Ipomeamarone
• found in “kumara”, member of the
sweet potato, results to injury,
insect attack. That can result to
bitter taste.

10. Furocoumarins
• found in “parsnips” that can cause
stomach ache, also cause a painful skin
reaction.

11. Glycoalkaloids
• found in all potatoes (particularly potato
sprouts, green potatoes. That can result to
abdominal pain, vomiting, diarrhea,
convulsion, hallucination, paralysis, and
occasionally death.

12. Lectins
• found in beans (kidney, lima, peas). Raw
kidney beans usually are toxic. (Do not cook
beans at low temperature, soak beans for at
least 5 hrs.)

13. Trypsin
• found in raw soybeans. It cause
depressed growth of rats, chicks)

14. Oxalic acid
• found in “rhubarb”, cause muscle
twitching, cramps, decreased breathing,
vomiting, pain, headache, convulsions and
coma.

15. Cucurbitacins
• found in wild zucchini that can cause
vomiting, stomach cramps, diarrhea and
collapse. (Do not eat zucchini that have a
strong unpleasant smell or bitter taste)

16. Cyanogenic Glycosides
• found in cassava and bamboo shoots (raw
or unprocessed cassava).
• To avoid exposure to toxin, should be
prepared before eating, cook cassava
thoroughly

17. Goitrogen
• found in cabbage, broccoli, cauliflower,
canola, that can result to goiter. (they are
lost by cooking)