The Use of Chemicals in Agriculture
minimum application of chemicals is indispensable for the protection
of plants and animals in high return-oriented agriculture. In the
European Union, more than 200,000 tons are deployed in the area of
plant protection products each year. With an annual consumption of
23,000 tons, of which 80% is used in crop production, Germany is the
fourth highest consumer of plant production products after France,
Spain and Italy. Considered in terms of the area of application,
herbicides (agents for control of undesired plants and grasses)
account for a good half of the total consumption. This is followed
by fungicides (chemicals to kill fungus and spores) and
insecticides. The volume used has fallen slightly in the Federal
Republic in recent years and has reached the level of the early
1990s. The reason for this is not a lower level of cultivation
intensity however, but primarily due to the replacement of older
products with chemicals that are effective at lower dosages.
However, the use of plant protection products also holds the potential of serious hazards for humans and the environment. Alongside the question of occupational safety for farmers, this primarily involves active agents entering the food chain and the water cycle. Of special significance here are chemicals that disturb the hormone system of organisms. These “endocrine disruptors” can, for example, damage the reproductive capacity of fish and consequently endanger entire populations in the long term. Further, current research findings confirm the suspicion that there is a relationship between the increased occurrence of such chemicals in the environment and the observed decline in male fertility in industrialised countries.
of today’s approved plant protection products have hormonal effects
is often a matter of dispute. The so-called
Weybridge definition provides a scientifically recognised
characterisation of the hormonal effect of a chemical. However,
there are still no standardised, generally accepted ecotoxicological
test procedures for the establishment of hormonal effects. A
comprehensive risk assessment also faces inherent difficulties.
Organisms are exposed to a whole cocktail of chemicals in their
environments. According to the current state of knowledge, it is
considered probable that negative effects – such as disturbance of
the hormone system – are cumulative here. This can cause the
occurrence of damage in organisms even where the individual
chemicals occur in concentrations that are considered harmless on
their own. It remains unclear how such mixture effects can be
adequately taken into consideration in the assessment of risks –
including those associated with plant protection products.
Risk Minimisation: The Limits of Legal Solutions
In Europe, measures to limit possible risks from the use of agrochemicals are primarily legally based. The foundation is provided by the European Council Plant Protection Products Directive 91/414/EEC of 15th July, 1991. Appendix I provides a list of the active substances for plant protection products that have been approved for the European market – currently over 300 different chemical compounds. The Plant Protection Products Directive is currently undergoing comprehensive review within the context of the 6th Environment Action Program of the European Union. A central consideration here is a general prohibition of the application of substances with hormonal effects. However, as the current debate in the EU shows, the criteria for the classification of substances as hormonally active are the subject of strong dispute.
This is compounded by an essential conflict of objectives: In some plant protection products – the fourth generation insecticides – the targeted influence on the hormone system of harmful insects is part of the product’s function. The extent to which these hormone-influencing insect growth regulators should be prohibited must be considered critically. As well as possible undesired damage to beneficial organisms and other non-targeted organisms, they also possess advantages when compared with conventional agents (reduction of the quantity required, increased occupational safety).
societal interest in the use of more effective agrochemicals for
safeguarding the high agricultural return levels and the demand for
precautionary health and environmental protection create a situation
in which the purely legal approach to the problem quickly confronts
its limits. Due to the partly uncertain scientific basis, an
evaluation of the higher legal interest in the case of doubt is
always dependent on the needs, interests and values of the different
stakeholders. Rigid bodies of rules cannot adequately resolve this
constantly changing, conflict laden situation. Although legal
instruments will remain indispensable, the question that is posed
is: What strategies exist for managing hormonally active
agrochemicals that can fully realise the entire spectrum of handling
options beyond state intervention? This question is addressed within
the context of the start2 research project.
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