Chemical risks for biodiversity
Contents
Which chemicals present risks for biodiversity?
Because current regulatory measures intended to test the effects of chemicals for biodiversity cannot appropriately address the complexity and dynamics of interactions between living systems, and with their abiotic environment.[1], this question has not been adequately addressed.
Chemicals can originate from millions of consumer, agricultural and industrial products and processes. In certain instances, the release of a chemical is accidental, while in others it is a side effect of other processes, or due to their intended form of use. Once in the environment, some chemicals can persist for long periods of time and/or be broken down into other chemicals with further risk properties.
Chemicals may also produce unforeseen health and environmental impacts when interacting with other natural or manufactured chemicals. For a variety of chemicals, “the dose makes the poison”. On the contrary, for many others, very low doses are enough for impacts to appear (e.g., disturbances to wildlife and ecosystems from low-level exposures to chemicals such as endocrine disruptors).
These and other physical and chemical transformations and the resulting human and environmental health impacts can go far beyond what existing regulations regarding the release of many chemicals (from zero emission safety provisions to standards of good practice) can adequately address. Emission patterns vary from point sources (where most data are available) to diffuse emissions from current and past activities: there are at least two million contaminated sites in the EU (European Commission, 2003).
Aquatic sediments can store certain chemicals and, with changing environmental conditions, release them either suddenly or over an extended period of time. Substances used in longlife products may be a major source of chemicals emissions both during their use and once they have been dumped in the environment (e.g. CFCs from isolation foam). In order to understand the (potential) effects of chemicals on living beings, risk assessments are based on laboratory studies, via testing organisms. Under the current risk estimation approaches in eco-toxicology, chemicals' effects are then estimated for groups like plants, invertebrates, fish, birds or mammals.
However, emerging properties at higher system levels inevitably escape assessments made at “micro” level. Consequently, there is a lack of knowledge of the effects of chemicals on systemic properties of biodiversity and on complex interactions among living beings. For example, it was shown that the effects of the combined presence of the herbicide atrazine and of high levels of nutrients, led to effects in frog populations due to changes in the ecosystem at large. Atrazine reduced phytoplankton growth, resulting in higher levels of nutrients and therefore higher levels of algae. These, in turn, fed a wider array of gastropods which are intermediate trematode hosts, which spread the infection to frogs. Standard procedures for chemical risk assessment could not possibly detect such a pollution–disease pathway, as long as species are studied in isolation, i.e. in the lab.
What is needed is an integrated impact monitoring. Unfortunately, environmental monitoring in Europe is “characterised by a plurality of monitoring networks operated under different administrative competences and environmental sectors. Only a small part of the collected data is evaluated in a cross-media and cross-sectoral perspective”[2]. Currently the available scientific knowledge is not structured and therefore it is hardly accessible. In effect, much of it is scattered in a large number of specialized journals.
REACH: Regulation on the Registration, Evaluation, and Authorization of Chemicals
The lack of systematic knowledge, as well as of understanding of chemical risks for biodiversity, has often been evoked in the political process that has led to REACH. This Regulation covers all chemicals produced or imported in volumes larger than 1 t/year and replaces over 40 existing Directives and Regulations. Guided by the precautionary principle, this Regulation has three overarching goals:
- Improving knowledge of the properties and uses of individual chemical substances,
- Increasing the speed and efficiency of the risk assessment process and
- Making producers and importers responsible for this process [3].
The link between chemicals and biodiversity is not obvious “at first sight” in REACH as it does not include a risk assessment for the “on-field biodiversity”. However, REACH assesses the risk of chemicals on living beings indirectly, through demanding that risk assessments be made in the laboratory, testing impacts on plants and animals, which are surrogates for the real biodiversity “out there” (based on the outcome of such risk assessments, the substances are authorised for marketing or not). Thus despite falling short of addressing the two problems mentioned above, i.e., diverse sensitivities and complex interactions, REACH is a major step forward towards a comprehensive testing system, as compared to the pre-REACH situation [4]. Nonetheless, there is still quite some room for improvement.
REACHing biodiversity protection
Weaknesses to be addressed within REACH
- The ecotoxicological data required cover the aquatic and terrestrial components of biodiversity, which could be at risk, only to a limited degree.
- There is no procedure for assessing the scientific quality of the data submitted for REACH.
- Once risky chemicals have been identified, encouraging substitution is one of the objectives of REACH, but it cannot easily be enforced. Substitution is not demanded if an overriding socio-economic need for the substance is proven.
Even if alternative, less risky substitutes exist, several of the higher risk substances must be allowed on the market if the producers demonstrate that they are able to control them adequately (for substances for which safety thresholds exist).
Furthermore, the ways in which REACH will be implemented can substantially influence the level and quality of data which will be provided by the industry
Weaknesses to be addressed beyond REACH
Adequately understanding the diverse reactions of organisms requires additional investment in public education and research in ecotoxicology to improve the knowledge base on components of biodiversity which are not dealt with in REACH, and provide additional knowledge on the target points addressed by REACH. Complexity problems require field monitoring systems for chemicals risks on biodiversity and the integration of existing monitoring schemes to enhance data comparability and boost monitoring systems’ efficiency. Except for periods of serious crises, the economic system which drives the present patterns of production in the chemical industry is not ready to change. As well, ideologies and lifestyles driving the patterns of chemicals uses are slow to modify. REACH implementation could become one tool to change their present state towards green innovation in chemistry and sustainable consumption in society.
Further reading
- Convention for Biological Diversity, 1992. Article 2: Use of terms. URL: http://www.cbd.int/convention/
- European Commission, 2003. Regulation of the European Parliament and of the Council concerning the Registration, Evaluation, Authorization and Restrictions of Chemicals (REACH), establishing a European Chemicals Agency and amending Directive 1999/45/EC and Regulation (EC) {on Persistent Organic Pollutants} - Extended Impact Assessment of the REACH proposals. Commission Staff Working Paper, COM(2003)644 final, Brussels, 33 pp.
- Rohr, J.R., Schotthoefer, A.M., Raffel, T.R., et al., 2008. Agrochemicals increase trematode infections in a declining amphibian species. Nature, 455: 1235-1240.
- Rudén, C. and Hansson, S.O., 2006. Improving REACH. Regulatory Toxicology and Pharmacology, 44:33-42.
Notes
- ^ “The variability among living organisms from all sources including, inter alia, terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part; this includes diversity within species, between species and of ecosystems” (Convention for Biological Diversity, 1992).
- ^Doyle, U. and Heiss, C., 2009. Bewertung von diffusen Stoffeinträgenim Rahmen der nationalen Biodiversitätsstrategie. Umweltwissenschaftliche Schadstoff Forschung, published online August 27th, 2009. DOI 10.1007/s12302-009-0081-1.
- ^Singhofen, A., 2005. REACH — how far will the new chemical legislation REACH to protect human health and the environment from hazardous chemicals? A comparison of the positions of the European Parliament and Council. Environmental Law Network International 2, 17–21.
- ^Maxim, L. et Spangenberg, J., 2009. Driving forces of chemical risks for the European biodiversity. Ecological Economics, 69(1): 43 – 54. (Chemical risks for biodiversity) Glossary
