Regulating the regulations and harmonizing the disharmonized: Challenges and issues of regulatory environmental hazard and risk assessments of chemicals
Thesis or dissertation
University of Exeter
Reason for embargo
This thesis contains a number of papers that are currently subject to copyright restrictions and therefore the thesis is embargoed to comply with copyright law
The focus of this thesis is the regulatory aspects of environmental hazard and risk assessment of chemicals, with a particular emphasis on whether current regulatory requirements are sufficient for assessing the risks chemicals pose to the environment. Since the way that chemicals are currently regulated on a global, regional or national level is complex and challenging, it is not surprising that there are faults with the current system. Legislations and regulations, such as the European regulation on Registration, Evaluation, Authorisation and restrictions of Chemicals (REACH), specifically indicates that unnecessary testing should be avoided wherever possible. However, this has not been the case for all hazard evaluations and some substances may have been assessed unnecessarily, or incorrectly resulting in significant underestimation of the potential effects to the environment. The aim of this research was to identify the major pitfalls and flaws with how environmental risk assessments are being performed, and to find a more harmonious approach to properly ensure that chemicals are regulated more appropriately. Within this thesis, there are examples of ecotoxicity studies for substances that should have little or minimal environmental consequences but which have been required for regulatory reasons. Such an example highlighted in this thesis is the artificial sweetener sucralose or silica fume. Conversely, other substances which are likely to have severe adverse environmental impacts could have been authorised for use inappropriately without the additional research that was carried out. Examples of potentially harmful chemicals not being regulated sufficiently, detailed in this thesis, include benzoylurea pesticides, used in aquaculture, and novel antifoulant substances such as thiophenones used in industrial processes. The papers in this thesis indicate that there is a large disparity between how some substances are being regulated. In order to improve the current situation and to aid environmental risk assessors and regulatory authorities, integrated strategies have been proposed incorporating all available data to collectively inform on for example the bioaccumulative properties of a substance. In addition, recommendations for improving the risk assessment processes are discussed with the aim of better regulating chemicals and harmonizing future environmental risk assessments.
PhD by Publication in Biological Sciences