The global roots of pre-1900 legacy mercury

Abstract

During the nineteenth century, a major change took place in the trade, production, and use of mercury that altered its nearly exclusive link to silver refining in the Hispanic New World. We track the global expansion of mercury markets in chronological detail from 1511 to 1900 using historical archives on production and trade, a detailed country-by-country accounting of the pool of anthropogenic mercury from which legacy mercury was ultimately generated. The nature and profile of pre-1900 legacy mercury extends beyond silver refining, mercury production, and gold extraction, and includes alternate sources (vermilion, felt, mercury fulminate) and new regions that were not major silver or gold producers (China, India, United Kingdom, France, among others), that accounted for approximately 50% of total mercury consumed in the nineteenth century. The nature of the pre-1900 mercury market requires a quantitative distinction between legacy mercury and historic anthropogenic mercury production and use, since the chemistry of its end-uses determines the pathways and timelines for its incorporation into the global biogeochemical cycle. We thus introduce the concept of a mercury source pool to account for total historic anthropogenic mercury within and outside this cycle. Together with a critical review of previous assumptions used to reconstruct the historical use and loss of mercury, a much lower level of emissions of pre-1900 legacy mercury is proposed. A coordinated effort across disciplines is needed, to complete a historically accurate scenario that can guide the multilateral policies adopted under the United Nations Minamata Convention to control mercury in the environment.

Keywords: Minamata convention; biogeochemical mercury cycle; global mercury trade; mercury emissions; mercury releases.

Fig. 1.

The historic Hg SP encompasses Hg PL, and the Hg market, both datasets available from archival documentary sources, together with losses in transit or storage. Legacy Hg is less than or equal to Hg SP, subject to the fraction of Chemically Sequestered Hg (CS Hg) that remains stable over time.

Fig. 2.

Global Hg production, markets, estimated PL, and unaccounted-for Hg, in Gg, 1551 to 1810. For tabulated data and sources, see SI Appendix, Table S1.

Fig. 3.

Hg SP derived from main Hg markets, PL by hemisphere, and unaccounted production, in Gg, 1551 to 1810. For tabulated data, see SI Appendix, Table S1.

Fig. 4.

Global Hg production, markets, estimated PL, and unaccounted-for Hg, in Gg, 1811 to 1900. For tabulated data and sources, see SI Appendix, Tables S4–S11.

Fig. 5.

Hg market and production loss (PL) by selected countries, and HgSP excluding unaccounted-for Hg (Hg SP*) by hemisphere. For tabulated data and sources, see SI Appendix, Tables S4–S11.

Fig. 6.

The HgSP excluding unaccounted-for Hg (Hg SP*) of selected countries, from 1811 to 1900, from where legacy Hg was generated. For tabulated data and sources, see SI Appendix, Tables S4–S11.

Fig. 7.

Fraction of Ag produced in the United States by smelting, 1875 to 1900. Derived from data from ref. (54) and ref. (55).

Fig. 8.

Gold production in Australasia vs Hg imports, 1851 to 1860 (56, 57) and SI Appendix, Table S11.