Report from the Sub-comittee on the environment and health

Definition of
proportionality
Heavy metals
136
addition, a coformulant must be declared on <strong>the</strong> label if it occurs in a
concentration of 0.2% or more in <strong>the</strong> case of very toxic and toxic
substances and 5% or more in <strong>the</strong> case of harmful or caustic substances.
7.2 Proportionality: <strong>the</strong> chemical impact in agriculture
Here, proportionality should be understood to mean a proportional
assessment of <strong>the</strong> harmful effects of pesticides on <strong>the</strong> environment and
health compared with o<strong>the</strong>r chemicals used in agriculture or
unintentionally added to <strong>the</strong> cultivated soil. It lies outside <strong>the</strong> scope of
<strong>the</strong> sub-committee’s mandate to examine <strong>the</strong> use of chemicals in o<strong>the</strong>r
sectors of society and to compare <strong>the</strong>se environmental impacts with <strong>the</strong>
environmental impact resulting <strong>from</strong> <strong>the</strong> chemicals used in agriculture. In
addition, <strong>the</strong> pesticides have been assessed against naturally occurring
toxins, and <strong>the</strong> use of naturally occurring substances as pesticides has
also been assessed. The assessment thus covers:
• chemical substances in agriculture
• chemical substances in food products
In <strong>the</strong> assessment, <strong>the</strong> sub-committee has assessed <strong>the</strong> current size of <strong>the</strong>
environmental load and its development, toge<strong>the</strong>r with its regulation, and
– lastly – <strong>the</strong> size of <strong>the</strong> load in relation to <strong>the</strong> occurrence and effects of
<strong>the</strong> pesticides.
7.2.1 Chemical substances in agriculture
Like <strong>the</strong> rest of society, conventional farmers are dependent on chemical
substances. The extensive use of fertilisers leads to loss of nitrogen and
phosphorus to <strong>the</strong> aquatic environment and loss of ammonia to
uncultivated land and forests. The use of chemical products has become
more widespread in <strong>the</strong> agricultural sectors in step with <strong>the</strong> increasing
demands concerning productivity. Such aids as fertiliser, ground chalk
and pesticides are used in <strong>the</strong> production of crops, wood pulp,
ornamental greenery, etc. Various waste products are used as fertilisers,
some of which can contain xenobiotic substances. Pharmaceuticals,
growth promoters and disinfectants are used in animal husbandry.
Finally, pollutants are transported in <strong>the</strong> air. They derive, e.g., <strong>from</strong> <strong>the</strong>
combustion of oil, coal, straw and waste, and traffic. The herbicidal
substance DNOC can be formed <strong>from</strong> air-pollution components during
atmospheric, chemical reactions, see section 4.5. Ozone is formed in a
complicated interaction between oxygen, combustion products and <strong>the</strong>
sunlight. Ozone can cause considerable damage to crops (Fenger 1995).
Cultivated land receives heavy metals <strong>from</strong> fertilisers, ground chalk,
sludge and o<strong>the</strong>r waste products and <strong>from</strong> manure. It also receives heavy
metals <strong>from</strong> <strong>the</strong> atmosphere. Both in Denmark and internationally,
pollution with heavy metals – particularly cadmium, lead and mercury –
has been considerably reduced. There are thus strict requirements
concerning <strong>the</strong> content of heavy metals in fertilisers, chalk, sludge and
o<strong>the</strong>r waste products. Cadmium is particularly problematical because
both manmade and natural dispersal of cadmium is diffuse and because
most cadmium compounds are relatively mobile in <strong>the</strong> environment.
Cadmium is absorbed by plants parallel with phosphorus and thus makes