Annex A. Selected examples of the integration of the PP into national and international law

Switzerland: Section 74, Paragraph 2 of the Federal Constitution: In principle, all the formulations of the concept of precaution in environmental protection are based on the notion that indeterminable risks are to be avoided. Section 1, Paragraph 2 of the Environmental Protection Act (EPA) [Umweltschutzgesetz, USG]: “Precaution as defined implies that any effects likely to be harmful or noxious are to be limited early on.” This formulation comprises the obligation to limit effects below the threshold of harmfulness and the obligation to limit effects for which no threshold of harmfulness can be ascertained by scientific means. Section 148a of the Agricultural Act [Landwirtschaftsgesetz]: revised as part of the 2007 Agricultural Policy, it defines the precautionary principle in accord with those of the EU (WHO, 2003[1]).

Greece: The PP is indirectly integrated in national law. Article 24 of the Greek Constitution: the state government takes “preventive or repressive measures” to ensure and support sustainability and protect the environment. In addition, Article 15 of the Basic Act on Biodiversity Conservation: the state should implement measures to “avoid any risk that threatens the structure of the ecosystems and prevents or reduces any environmental” damage" (Koehler, L., Giovos, I., & Lowther, J., 2022[2]).

Sweden: Chapter 2, Section 3 of the Environmental Code (1998): it adheres to the strong version of the principle and includes two important aspects: the requirement to take measures to prevent harm applies already when there is a scientifically established risk thereof; and, in order to avoid the requirements, the operator must show that there is no risk ( (Michanek, 2007[3]); (Michanek, 2012[4]) (Pettersson, 2016[5]).

In some EU countries such as Belgium or the Netherlands, the courts recognise the precautionary principle provided that it has been included in a normative text. In Belgium, the principle was first introduced in Belgian legislation in a decree of the Flemish Region of 5 April 1995, while on a federal level it was reiterated in the Federal law of 30 January 1999, aimed at protecting the marine environment in the maritime areas under Belgian jurisdiction (Article 4). In the latter, the principle is directly binding on all users of the marine environment, both public and private (Nicolas De Sadeleer, 2000[6]).

Italy: The Environment Code includes many explicit references to the PP. Article 3 enumerates it as one of the general principles of environment law, and Article 301 is called "the conversion of the precautionary principle”. The first paragraph stipulates that, in the presence of dangers (potential or confirmed), a high protection level must be guaranteed, even in the absence of scientific certainties on the risk existence. The following paragraphs delimitate the application of the principle (in compliance with the European Commission Communication on 2 February 2000), especially stipulating that the application of the principle refers to the risk that may be identified after a preliminary objective scientific assessment. The principle is also invoked in certain normative technical deeds, such as: the Law no. 36/2001 (about the protection against the exposure to electric, magnetic and electromagnetic fields), the Legislative Decree of the Government no. 224/2003 (on the deliberated dissemination of the genetically modified organisms in the environment), and the Legislative Decree of the Government no. 257/2006 (on the protection of workers from the risks related to exposure to asbestos at work) (Fainisi, Florin; Ilie, Marian; Artene, Diana Anca, 2012[7]).

In other countries such as Spain, the principle was not raised to the rank of constitutional principle and the courts based their decisions on the precautionary principle only if the provisions under consideration derived from European legislation. The first domain covered through legislation was environmental protection with Law no. 11/2001 (on the creation of the Spanish Agency for food security), and later Law no. 9/2003 (establishing the legal regime around the limited use and commercialisation of genetically modified organisms; it stipulates that the principles on which the law is based are those existing in the European and international area). The autonomous communities of Spain also have the legal capacity to introduce the principle in their legislation (e.g., the Catalan law on the food security, and the law on public health in the Valencia region) (Fainisi, Florin; Ilie, Marian; Artene, Diana Anca, 2012[7]).

The 1990 Ministerial Declaration of the Third International Conference on the Protection of the North Sea stated that the contracting governments “will continue to apply the precautionary principle, that is to take action to avoid potentially damaging impacts of substances that are persistent, toxic and liable to bioaccumulate even where there is no scientific evidence to prove a causal link between emissions and effects”.

The PP achieved global recognition in 1992 when it was included in Article 15 of the Rio Declaration resulting from the UN Conference on Environment and Development. The provision makes the precautionary approach a guiding principle for the management of forests: “In order to protect the environment, the precautionary approach shall be widely applied by States according to their capabilities. Where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation”. By this definition, the precautionary principle is the duty of a state and scientific uncertainty should not be used to avoid adopting precautionary measures that could prevent environmental degradation.

At EU level, the PP was enshrined in the Maastricht Treaty in 1992 and it is now included in Article 191 of the Treaty on the Functioning of the European Union. However, the PP is not defined in the Treaty. It states: “Union policy on the environment shall aim at a high level of protection taking into account the diversity of situations in the various regions of the Union. It shall be based on the precautionary principle and on the principles that preventive action should be taken, that environmental damage should as a priority be rectified at source and that the polluter should pay.” Hence, through the Maastricht Treaty, the precautionary principle has acquired constitutional status. The PP was formally articulated by the European Commission’s Communication on the Precautionary Principle (see Box 2.2), which was subsequently endorsed by the Council of Ministers (Nice Resolution). The Communication states that: “The precautionary principle applies where scientific evidence is insufficient, inconclusive or uncertain and preliminary scientific evaluation indicates that there are reasonable grounds for concern that the potentially dangerous effects on the environment, human, animal or plant health may be inconsistent with the high level of protection chosen by the EU”.1

Another well-known definition of the PP was formulated with the Wingspread Statement. In 1998, at the Wingspread Conference on the Precautionary Principle, the PP was defined as follows: “When an activity raises threats of harm to human health or the environment, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically”. This definition also involved a reversal of the burden of proof.


[7] Fainisi, Florin; Ilie, Marian; Artene, Diana Anca (2012), The Insertion of The Precautionary Principle in The Environment Protection as A Legal Norm in The European Union Countries, pp. 489–508,

[2] Koehler, L., Giovos, I., & Lowther, J. (2022), “The application of precaution in elasmobranch conservation and management in the Mediterranean Sea”, Marine Policy, 135, 104830.,

[8] Lofstedt, R. (2004), The Swing of the Regulatory Pendulum in Europe: From Precautionary Principle to (Regulatory) Impact analysis.

[4] Michanek, G. (2012), Den svenska miljörätten (3rd ed.), Iustus förlag.

[3] Michanek, G. (2007), Implementing the precautionary principle: approaches from the Nordic countries, EU and USA, Earthscan / James & James.

[6] Nicolas De Sadeleer (2000), The Enforcement of the Precautionary Principle by German, French and Belgian Courts.

[5] Pettersson, M. (2016), “The role of the precautionary principle and property rights in the governance of natural resources in Sweden”, Nordic Environmental Law Journal,,%2010%20maj%20Pettersson,Goytia.pdf.

[1] WHO (2003), The Precautionary Principle in Switzerland and Internationally,


← 1. Lofstedt reports that in the period 1994 to 1999, the term “precautionary principle” was referred to in 27 European Parliament resolutions (Lofstedt, 2004[8]).

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