Mercury is a naturally occurring, but very toxic metal that can have detrimental effects upon humans and other forms of life (biota) if not properly managed. This section ‘sets the scene’ by providing an overview of the mercury and mercury pathways in the environment. It draws on a review of the international literature and consultation with New Zealand industry experts and other authorities, to provide a short summary of the types of mercury that are present in the environment, and the impacts that mercury can have upon biota.
An overview of mercury circulation at both the global and national scale is also provided. The global mercury circulation pathway is presented in graphical form, and the transport and transformation of mercury throughout the environment is generally described.
This section also summarises in graphical form mercury pathways within the New Zealand environment. It explains the special features of mercury circulation patterns within New Zealand, which have a notable volcanic and geothermal component. It then briefly places in context the issues presented by the relative contribution of mercury-containing lamps to New Zealand’s mercury flow, with further investigations and details on these matters to be presented in subsequent sections.