GLOBAL MERCURYASSESSMENT 2018
KEY FINDINGSUnited Nations Environment Programme

KEY FINDINGSThe Global Mercury Assessment 2018 is the fourth such assessment undertaken by The United Nations
Environment Programme (UN Environment), following earlier reports in 2002, 2008, and 2013. It is
the second assessment produced by UN Environment in collaboration with the Arctic Monitoring andAssessment Programme (AMAP). The assessment is supported by a technical background document, thechapters of which have been prepared by teams of experts and peer-reviewed for scientific quality. Thissummary document presents the main findings of the technical document in plain language. Recognizing
the relevance of the results of the Global Mercury Assessment 2018 for policy makers, this section
presents key findings of highest policy relevance.

KEY FINDING 1

Larry C. Price

A new global inventory of mercury
emissions to air from anthropogenic
sources in 2015 quantifies global
emissions from 17 key sectors at
about 2220 tonnes.
There are also smaller anthropogenic sources that it is not yet possible
to quantify in the detailed global inventory. Total emissions from these
additional sources are evaluated to total of the order of tens to hundredsof tonnes per year. They would therefore not significantly change the total
global emissions inventory but may be of local or regional significance.

SmerbyStudio/Shutterstock.com

KEY FINDING 2

Estimated global anthropogenic emissionsof mercury to the atmosphere for 2015 areapproximately 20% higher than they werein updated estimates for 2010.
Continuing action to reduce emissions has resulted in modest decreases
in emissions in North America and the European Union. Increased
economic activity, notably in Asia, and the use and disposal of mercuryadded products appears to have more than offset any efforts to reduce
mercury emissions.

KEY FINDING 3Emissions patterns in 2015 arevery similar to those in 2010.

Larry C. Price

The majority of the 2015 emissions occur in Asia (49%; primarily Eastand South-east Asia) followed by South America (18%) and Sub-SaharanAfrica (16%). Emissions associated with artisanal and small-scale gold
mining account for almost 38% of the global total and are the major
contributor to the emissions from South America and Sub-Saharan Africa.
In other regions, emissions associated with energy production andindustrial emissions predominate.

KEY FINDING 4

savva_25 / Shutterstock

Stationary combustion of fossil fuels andbiomass is responsible for about 24% of
the estimated global emissions, primarily
from coal burning (21%).
Main industrial sectors remain non-ferrous metal production (15% of theglobal inventory), cement production (11%) and ferrous metal production(2%). Emissions from waste that includes mercury-added products
comprise about 7% of the 2015 global inventory.

Global Mercury Assessment 2018

KEY FINDING 5

tanakornsar / ShutterstockHuman activities have increased total
atmospheric mercury concentrations
by about 450% above natural levels.
This increase includes the effects of mercury emitted from human sourcesin the past which is still circulating in the biosphere, known as legacy
mercury. Historical emissions up to the end of the 19th century, mainly fromgold, silver, and mercury (cinnabar) mining and refining in the Americas,
contributed more to the present-day anthropogenic mercury in soils andthe oceans than all 20th century industrial sources combined. The presenceof legacy mercury and the potential for climate change to influence its
remobilization complicates our ability to assess potential future changes.

KEY FINDING 6

Larry C. Price

Artisanal and small-scale gold mining
introduced about 1220 tonnes of mercury
into the terrestrial and freshwater
environments in 2015, but this amountcannot be reliably separated between
discharges to soils and releases to water.
Global releases of anthropogenic mercury from other sources to aquatic
environments totalled about 580 tonnes in 2015. The major sectors
contributing to these 580 tonnes are waste treatment (43%), ore mining
and processing (40%), and energy (17%).

KEY FINDING 7

The Stephen Low Company

Natural production of methylmercury inthe oceans and in some lakes is no longer
limited by the input of inorganic mercury.
Other factors such as climate change, biogeochemistry, and changes insoil processes are playing increasingly important roles in the mercury
cycle, affecting the distribution and chemical interactions of mercury inthe environment.

United Nations Environment Programme

Global Mercury Assessment 2018

KEY FINDING 8Reductions in mercury emissions
and resulting declines in atmosphericconcentrations may take time toshow up as reductions of mercury
concentrations in biota.

Pure Earth

For some time to come, methylmercury will continue to be produced
from the legacy mercury already present in soils, sediments, andaquatic systems.

KEY FINDING 9

Mercury loads in some aquatic foodwebs
are at levels of concern for ecological andhuman health.

Daniel Poleschook

Anthropogenic mercury emissions and releases, current and legacy,
are the major contributors to increased mercury levels and exposure.

KEY FINDING 10WILDLIFE GmbH / Alamy Stock PhotoAll people are exposed to someamount of mercury.
For many communities worldwide, dietary consumption of fish,shellfish, marine mammals, and other foods is arguably the mostimportant source of methylmercury exposure. Exposures toelemental and inorganic mercury mainly occur in occupationalsettings (including artisanal and small-scale gold mining) or via
contact with products containing mercury. There remains highconcern for vulnerable groups including various indigenous
populations with high dietary or occupational exposure to mercury.

The Global Mercury Assessment 2018 is based on improved information for estimating emissions and releases and improved understanding of themercury cycle in the environment. In addition, the 2018 report provides new information about mercury exposure in animals and humans. These
improvements are the result of mercury research and monitoring around the world. They provide a strong base of knowledge to support actions toreduce mercury emissions and releases and to reduce ecosystem and human exposure.
Further improvements in our understanding of mercury can further refine the ability to identify efficient actions to reduce mercury pollution andits effects. Such improvements include basic research on aspects of the mercury cycle as well as systematic monitoring methods to expand thegeographic coverage of measurements of mercury pollution. As a chemical element, mercury cannot be destroyed. Mercury removed from fuels
and raw materials in order to reduce emissions will result in mercury-contaminated waste, which in turn can be a source of releases. Mercury
removed from emissions and from releases must still be managed responsibly to avoid it becoming a waste management problem or a secondary
source. Understanding how mercury removed from current uses and sources is currently managed and how it can be safely managed and stored
in the future will help account for the full life-cycle of mercury that is mobilized through human activity, safeguarding the environment and humans
when it is removed.

Cover photograph: Andrew Sutton/Shutterstock.com
Design: Burnthebook.co.uk

United Nations Environment Programme
P.O. Box 30552 Nairobi, Kenya
Tel: ++254-(0)20-762 1234
Fax: ++254-(0)20-762 3927
E-mail: uneppub@unep.org
www.unep.org