SAFETY
ALERT
65
JUL 2017 FOOD FOCUSTHAILAND
HistamineToxicityand Its Impact onExports
Aseverecasedocumented in2007 inSamutPrakarnprovince,
28patientswho consumed fried fermented tuna containinghigher
level of histamine than 400 ppm had symptoms include nausea,
vomiting, numbness of hands and feet.Another incident occurred
in 2012, "Spain" banned canned tuna fromThailand notifying that
the products exporting toEUwere not met theEnfaco standards.
TheSpanishConfederationofCannedFoodhassubmitteda letter
to theSpanish government demanding the ban on importing tuna
fromThailand temporarily.Byciting thatmany importersof canned
tuna fromThailanddidnot follow theEU foodhygiene regulations.
As a result of this incident, many countries are now focusing on
histamine content as an indication of the quality of each seafood
and fishery product.
Samples of the Presence and Content of Histamine
Determined by Fish Species andRegulations of the Country
Concerned
1. Tuna, Scombridae, mackerel, cupeiformes, and saba
• Australia, NewZealand and Israel are restricted a limit of
not more than200ppm.
• Canada,EU, andother countriesallowcountsof notmore
than100 ppm.
• TheUnitedStates allows a detecting level at amaximum
of 50 ppm.
2. For Japan, tuna, salmon,mackerel andherringareallowed
todetect not more than 100 ppm.
3. Dried anchovy and dried tuna are limited to not more than
200 ppm inall countries
4. Fishsaucecanbedetectednotmore than500ppm inevery
country except Canadawhere limited to nomore than 200 ppm.
5. For all countries, saltedmackerel can detect nomore than
200ppm.
6. In all countries, steamed Scombridae can be detected not
more than 100ppm.
HeavyMetalsFound inTuna
The two main sources of heavy metals contamination in aquatic
animals are found in thenatureandanthropogenic. Heavymetals
areanaturalcomponentof theerosionand theEarth’scrustwashed
withheavymetals. Ingeneral,naturewouldachieveanequilibrium
among itsconstituent elements.Theheavymetalswhichoccurred
from human actions are derived from the use of heavymetals to
exploit the industry and release unwanted waste into the
environment, such as mining, as well as a disposal of waste
from the community, petrochemical industry, together with the
chemicalsused inagriculturalareas,activitiesseriesofmetals,and
others.
Some Specific Heavy Metals Commonly Found
inTuna
1.Mercury (Hg):
Mercury-containingsewage releasing into the
sea causes accumulation of mercury in aquatic animals. Larger
fish such as tuna aremore likely to containmercury than smaller
fish.Consumingof tunaandmercury-containingaquaticorganisms,
themercury canbe promptly harmful to thehealth.
Theaquaticanimalscanget themercurydirectlybyexchanging
of gas in the respiration process and indirectly through the food
chain of living things. So, fast-moving and hunter fish that need
References
highoxygenwillhavehigh levelsofmercury
in their tissues. These types of fish
includesailfish,sharksand tuna,etc.
However, the transmission of
mercury through the food chain
is the main route of mercury
accumulated into the fish.
Mercury contaminated in
food ishighlystable. Itcannot
be dissolved by cooking or
heat processing. Having
foods contaminated with
mercurycancausesymptoms
includingoral mucosa, swollen
gums and gingivitis, very bad
tooth pain, rocking teeth and
eventually falling off. It also affects
the digestive system.
2. Arsenic (As):
is a semi-metal
element that canbemost commonly found in
nature, such as soil, rocks, water sources, volcanic
eruptions, or coal burning, as well as from the use of fertilizers
and herbicides or insecticides. Arsenic is also used as a raw
material in the industryproducingbatteries,electricaldevices,alloys
and auto parts. The use of these heavy metals in some industrial
may lead to the release of wastewater or agricultural processes
discharge the waste contaminated with arsenic in pesticides or
manure fertilizers. When it rains, arsenic may be washed into
theenvironment, suchassoil, rivers, theseaor theocean, etc. The
aquatic animals living in such water resources accumulates
arsenic into the body. Consumers then get such substance into
their bodies when consuming those contaminated aquatic
animals.
Arsenic has been foundnaturally in twodifferent types: organic
arsenic and inorganic arsenic. The toxicity of a particular arsenic
compounddependson types, amount anddurationof the ingestion.
Inorganicarsenic is consideredmore toxic thanorganic formand is
known as a human carcinogen. However, a lower intake of arsenic
can be excreted from the body through the urine in a few days
followingexposure. But, if thesearsenic compounds accumulate in
thehumanbody for prolongedperiods in concentration sufficient, it
may cause poisoning.
As above mentioned of the incidents caused by heavy metal
poisoning, it cannot bedenied that nowadays, bothgovernment and
privateagencies locallyandabroadhavepaidmuchattention to the
hazardousof thesematters.Manycountrieshaveestablished rules
and regulationsgoverningfishingproceduresall theway to thequality
inspectionsof importedproducts.Thestandardsofwhich thoroughly
control productionprocesses toaccomplish thesafetyof consumers
andbe in linewith the requirementsof theproductsexported toother
countries.
