El estudio de los sedimentos de lagos andinos situados a gran altitud, ha revelado por vez primera que la contaminación por mercurio empezó mucho antes de la revolución industrial.Según el estudiante de doctorado Colin Cooke, de la Universidad de Alberta y cuyas investigaciones son financiadas por National Geographic, "la idea de que la contaminación por mercurio empezó antes de la revolución industrial era una antigua hipótesis, que nunca había sido comprobada".
Cooke y su equipo recogieron columnas de sedimentos de lagos a gran altura localizados cerca de Huancavelica (Perú) que es el mayor depósito de mercurio del nuevo mundo. Midiendo la cantidad de mercurio en las columnas a lo largo del tiempo, pudieron reconstruir la historia de la minería del mercurio y de la contaminación en la región.
Según Cooke, "hemos encontrado que la minería, y las emisiones de polvo aparecen ya en en el 1.400 AC... Sorprendetemente, la minería comenzó antes de la apaición de sociedades complejas o muy estratificadas. Esto es un cambio sobre las opiniones actuales, que sugieren que la minería solo emepzó después de la aparición de estas sociedades"
The study of ancient lake sediment from high altitude lakes in the Andes has revealed for the first time that mercury pollution occurred long before the start of the Industrial Revolution."The idea that mercury pollution was happening before the industrial revolution has long been hypothesised on the basis of historical records, but never proven," said Colin Cooke, PhD student at the University of Alberta, and whose research was funded by the National Geographic Society.
Cooke and his team recovered sediment cores from high elevation lakes located around Huancavelica (Peru), which is the New World's largest mercury deposit. By measuring the amount of mercury preserved in the cores back through time, they were able to reconstruct the history of mercury mining and pollution in the region.
"We found that mercury mining, smelting and emissions go back as far as 1400 BC," said Cooke. "More surprisingly, mining appears to have began before the rise of any complex or highly stratified society. This represents a departure from current thinking, which suggests mining only arose after these societies emerged"
Tomado de/ Taken from Science Daily
Más información/More information National Geographic
Resumen de la publicación científica/ Abstract of the paper
Over three millennia of mercury pollution in the Peruvian Andes
Colin A. Cooke, Prentiss H. Balcom, Harald Biester and Alexander P. Wolfe
Proceedings of the National Academy of Sciences, 2009; DOI: 10.1073/pnas.0900517106
Abstract
We present unambiguous records of preindustrial atmospheric mercury (Hg) pollution, derived from lake-sediment cores collected near Huancavelica, Peru, the largest Hg deposit in the New World. Intensive Hg mining first began ca. 1400 BC, predating the emergence of complex Andean societies, and signifying that the region served as a locus for early Hg extraction. The earliest mining targeted cinnabar (HgS) for the production of vermillion. Pre-Colonial Hg burdens peak ca. 500 BC and ca. 1450 AD, corresponding to the heights of the Chavín and Inca states, respectively. During the Inca, Colonial, and industrial intervals, Hg pollution became regional, as evidenced by a third lake record ≈225 km distant from Huancavelica. Measurements of sediment-Hg speciation reveal that cinnabar dust was initially the dominant Hg species deposited, and significant increases in deposition were limited to the local environment. After conquest by the Inca (ca. 1450 AD), smelting was adopted at the mine and Hg pollution became more widely circulated, with the deposition of matrix-bound phases of Hg predominating over cinnabar dust. Our results demonstrate the existence of a major Hg mining industry at Huancavelica spanning the past 3,500 years, and place recent Hg enrichment in the Andes in a broader historical context.
