Report from the Sub-comittee on the environment and health

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effect that can be expected per year or <strong>the</strong> safety margin between <strong>the</strong> actual level
and <strong>the</strong> level at which it begins to become possible to observe <strong>the</strong> effects (Danish
Government 1998). The individual pesticide, which has a margin of more than 1000,
is thus less dangerous than any of <strong>the</strong> metals lead, cadmium and mercury, which
have a low margin of 2-10. Question marks indicate that <strong>the</strong>re is too little
knowledge on which to base an assessment.
Cause of effect Human risk or safety margin
Natural toxic substances
Aflatoxins 500
Trichotecenes Margin>1000
Fumonisines Margin>1000
Algal toxins ?
Toxic constituents in food plants Estimated > 20 cases of poisoning per
million per year
Toxic constituents in edible fungi ?
Toxic constituents in health-food plants ?
Chemicals in food
Additives Margin>100
Aromatics ?
Pesticides Margin>1000
Veterinary drugs Margin>100
Lead, cadmium, mercury Margin 2 - 10
Nickel ?
O<strong>the</strong>r metals, boron, platinum, arsenic ?
Nitrate Margin < 10 (*)
Dioxins Margin 5 -10
PCBs Margin 5 -10
Persistent chlorinated pesticides Margin 10 -500
O<strong>the</strong>r persistent organic environmental
contaminants
?
O<strong>the</strong>r organic environmental contaminants ?
Migration <strong>from</strong> packaging, phthalates and
bisphenol A
?
PAH 20-60 extra deaths <strong>from</strong> cancer per
million per year
Nitrosamines 0.04-0.4 extra deaths <strong>from</strong> cancer per
million per year
(*): Nitrate can be converted into nitrite, which can cause acute poisoning in infants
and can contribute to <strong>the</strong> formation of carcinogenic nitrosamines. It is not possible to
set a margin.
7.3 Natural substances
All plants contain varying concentrations of toxic substances to protect
<strong>the</strong>mselves against attack by viruses, microorganisms and herbivores,
particularly insects. However, through evolution, <strong>the</strong> different species of
microorganisms and animals have specialised in living <strong>from</strong> plants that
are o<strong>the</strong>rwise poisonous to o<strong>the</strong>r organisms. Common examples of such
poisonous plants are deadly nightshade, spring groundsel and cow
parsnip. The last two of <strong>the</strong>se are imported, non-indigenous species that
are not regulated by natural enemies that tolerate <strong>the</strong> plants’ constituents.
Humans eat only a few plant species – normally less than 100. Although
some crop plants contain substances that have a toxic effect on certain
o<strong>the</strong>r groups of organisms, most of <strong>the</strong>m have very little toxic effect on