Abstract

Copper has been in use by mankind for eight to nine thousand years but it was very recently only that it acquired its reputation for being toxic for human health and the environment. This happened after individuals attempted to commit suicide with copper sulfate in the 19th century. In 1912, a disorder of the human nervous system associated with liver cirrhosis and excess copper was described by S.A.K. WILSON and it was later shown to be due to a defective recessive gene responsible for excretion through the bile. Copper toxicity in animals also began to be studied systematically in the first half of the 20th century. It was not until the end of the 1980's, nevertheless, that copper was included - for the first time at global level - in a list of toxic substances. This occurred in the Basel Convention for Transboundary Movements of Hazardous Wastes. And then came an avalanche. In 1991, the U.S. Environmental Protection Agency, USEPA, created the lead and copper rule which regulated copper in drinking water due to its potential gastrointestinal effects. That same year, the World Health Organization, WHO, decided to include copper in its list of chemicals of health significance in drinking water, due to its potential chronic liver effects. The copper industry, even though it took two years - until the guideline value of the WHO was published in 1993 - in realizing this momentous change, understood that this was a turning point in the long history of the metal. It was necessary to solve these issues but it was clear that in order to have capacity to negotiate with any of these organizations, it was necessary to have sound scientific knowledge. And since the industry did not have it, it was not even able to sit at the same table with these regulatory agencies. Fifteen years after these events, much progress has been made in the understanding of these issues, but we are still far from being able to answer all the questions, and I would say, even the most relevant questions. Some of the original concepts posed by the WHO and the Basel Convention were proved to be wrong but new issues emerged with the progress of science. Indeed, the scientific challenge is far greater at present than it was 15 years ago due to the complexity of the science involved, and also the regulatory pressure at present is not based only in the developed world as it was then. This paper discusses the main changes occurred in this brief time period regarding the health and environmental regulatory status of copper and the main trends understood at present, as well as its potential impacts on copper markets.