Report from the Sub-comittee on the environment and health

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6.2.7 Conclusions
There is insufficient epidemiological evidence to ei<strong>the</strong>r prove or disprove
a relationship between health effects and long-term low-dose exposure to
pesticides. There are several reasons why <strong>the</strong>re are considerable
difficulties in gaining more certain knowledge about <strong>the</strong> effect of
pesticides on human health. The epidemiological studies concerning <strong>the</strong>
effects on humans of exposure to pesticides are characterised by
imprecise measures for both exposure and effect, a relatively short
follow-up period and lack of control of confounding factors. Due to
limited group sizes, data are often collected in large groups, which
fur<strong>the</strong>r reduces <strong>the</strong> sensitivity. Owing to low exposure contrast and many
confounding factors, <strong>the</strong>re are often problems in proving any effects.
The following specific conclusions can be drawn:
• For a relationship to be demonstrated epidemiologically, better
measures are needed for both exposure and effect. The development
of biomarkers may be a step in this direction.
• It is important to constantly update <strong>the</strong> test methods for animal tests
based on scientific development on <strong>the</strong> basis of experience in humans.
• The review of <strong>the</strong> pesticide intake <strong>from</strong> food products and drinking
water shows that <strong>the</strong> main sources of <strong>the</strong> population’s exposure is <strong>the</strong>
intake <strong>from</strong> berries, fruit and vegetables and, to some extent, cereals
and cereal products, while <strong>the</strong> intake <strong>from</strong> drinking water, animal
food products and fish is of no significance to <strong>the</strong> total exposure.
• The total average load <strong>from</strong> food products is estimated to be approx.
200 microgrammes pesticide per day, more than half of which comes
<strong>from</strong> just a few types of food products, namely citrus fruit, potatoes
and apples. Around 60% come <strong>from</strong> imported products and 40% <strong>from</strong>
Danish products. There are big variations in <strong>the</strong> calculated numerical
values, and, in practice, <strong>the</strong> total intake is believed to range between a
very low intake and about 600 microgrammes per day. Since most of
<strong>the</strong> pesticide residues in citrus fruits are in <strong>the</strong> peel, which is not
eaten, <strong>the</strong> actual daily intake of pesticides is less than 200
microgrammes per day. In <strong>the</strong> last-mentioned scenario, <strong>the</strong> intake via
Danish products would be greater than 50% of <strong>the</strong> total intake.
• In treated crops it is assumed that <strong>the</strong>re is generally some residual
content of pesticides that decreases <strong>the</strong> longer <strong>the</strong> time that elapses
between spraying and harvesting. This is, however, a factor that is
particularly important if <strong>the</strong> pesticide is applied on crops or parts of
plants that are edible at <strong>the</strong> time of harvest, i.e. after <strong>the</strong> end of
flowering, seeding and similar. However, in farming practice, <strong>the</strong>re
are a number of o<strong>the</strong>r factors that influence <strong>the</strong> pesticide content of
<strong>the</strong> crop. This applies not only to <strong>the</strong> plant’s development stage at <strong>the</strong>
time of treatment but also to <strong>the</strong> concentration used, <strong>the</strong> method of
application, etc. However, failure to detect residues does not mean
that <strong>the</strong> crop is free of pesticides, but ra<strong>the</strong>r that <strong>the</strong> content is below
<strong>the</strong> analytical detection level.