272 EFFECTS OF CHEMICALS
In Japan in 1968 about 1800 people developed a malady
similar to chloracne after ingesting rice oil contaminated
with a chlorinated biphenyl. Known as Yusho or Rice Oil
Disease, the rice oil used in cooking had been contaminated
by a PCB which had leaked from a faulty heat exchanger.
In 1978 an outbreak similar to Yusho Disease occurred in
Taiwan and is known as the Yu-Cheng Incident. The cause
was the same, a faulty heat exchanger.
The last group, synthetic chemicals, includes pesticides
and fertilizers used in agriculture, food additives, compounds
containing heavy metals, plasticizers, fuel additives, house-
hold chemicals, industrial chemicals, therapeutic and pro-
phylactic drugs, and drugs of abuse. Food additives may be
intentional or accidental. Anti-oxidants and dyes are added
routinely to many foods. However, almost any of the afore-
mentioned may be accidentally introduced into food, often
with most unpleasant results. There is much controversy
concerning synthetic agriculture chemicals. Advantages and
disadvantages are numerous and no definite decision has
been reached concerning continued use of many substances.
NTA (Nitrilotriacetic Acid) as a substitute for phosphates in
detergents, is another excellent example of conflicting use.
The problem is far from restricted to simple direct physi-
ological effects.
Food additives may be classified as to function. They
find use as coloring material, flavor enhancers, shelf life
extenders, and in protection of food nutritional value. While
valuable, color additives are not always essential. However,
many of the foods now enjoyed by modern western society
would not be possible, in their present form, without food
additives.
It is estimated by the World Health Organization that
about one fifth of the food produced in the world is lost by
spoilage. Preservation, or retardation of spoilage, can be
accomplished by addition of chemical preservatives, or by
physical means such as freezing, drying, souring, ferment-
ing, curing or ionizing radiation. There is some concern
that irradiation of food may have adverse effects and leave
unwanted residues. Little is known about possible chemical
chain reactions.
Food additives have been classified by Kermode into
five broad groups:1) Flavors
2) Colors
3) Preservatives
4) Texture agents
5) MiscellaneousIn Table 1 are displayed food additives declared by the
United States Food and Drug Administration to be “gener-
ally recognized as safe.” Not included in Table 1 is a large
group of natural flavors and oils. To be on the list an additive
must have been in use before 1958 and meet specifications
for safety. Materials introduced after 1958 must be tested
individually in order to quality for inclusion of the FDA list.
Examples of materials formerly listed but now removed are
cyclamate sweetners and saccharin. A ban on cyclamatesordered by the US government after tests revealed devel-
opment of bladder cancer in laboratory rats fed on a diet
containing cyclamates. Further testing, after the ban, found
cancer development in the same test species at dosage rates
one sixth as large as those which brought about the ban.TABLE 1
Additives listed by the U.S. Food and Drug Administration as
“generally recognized as safe.” (Courtesy, Scientific American )
ANTICAKING AGENTS
Aluminum calcium silicate
Calcium silicate
Magnesium silicate
Sodium aluminosilicate
Sodium calcium aluminosilicate
Tricalcium silicate
CHEMICAL PRESERVATIVES
Ascorbic acid
Ascorbyl palmitate
Benzoic acid
Butylated hydroxyanisole
Butylated hydroxytoluene
Calcium ascorbate
Calcium propionate
Calcium sorbate
Caprylic acid
Dilauryl thiodipropionate
Erythorbic acid
Gum guaiac
Methylparaben
Potassium bisulfite
Potassium metabisulfite
Potassium sorbate
Propionic acid
Propyl gallate
Propylparaben
Sodium ascorbate
Sodium benzoate
Sodium bisulfite
Sodium metabisulfite
Sodium proponate
Sodium sorbate
Sodium sulfite
Sorbic acid
Stannous chloride
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