Mercury

So, this is slightly unrelated to photography, but interesting nonetheless. We took the boat ride back to Puerto Maldonado yesterday and were able to observe the Madre de Dios River from a different perspective. Since our initial journey upriver I have learned a lot about some of the threats to the Amazonian region. When I was little I always remember hearing and reading about "saving the rainforest" and as I've grown older the threats of deforestation and global warming have become one of my main academic interests. However, until this trip I was not aware of one of the main threats to the forest and its inhabitants. Alluvial gold mining is actually causing some of the worst and little known destruction to the rivers and forests. Gold is currently washed down from the uplands and it accumulates as dust in the river beds. Intensive mining has been affecting the region for more than 20 years. The first threat to the river is the dredging of sediment and the second, and main threat, is the mercury used in the mining. The miners use mercury because it adheres to gold. They mix the mercury in barrels with their bare feet by stomping on the sediment and mercury mixture and the gold clumps up with the mercury. After this process they burn the mercury off because mercury vaporizes much more quickly than gold. So, mercury enters the river when they pour the sediment back into the river and when the mercury is burned off. Mercury causes severe neurological and other health affects in humans as you may know from the care that your parent's take with mercury themometers - a small spill can start a panic in an American household.

Mercury is a huge problem because it bioaccumulates in the food chain - so the mercury in the water gets into the fish and actually stays in their muscle tissue. Then other animals eat the fish and they also ingest the mercury. A researcher at the station was actually studying the affects of mercury in raptors and is finding high concentrations of mercury in the blood and feather tissues of raptors, even those species that do not feed on fish or other animals from the river. In other words, mercury is climbing the food chain. This is very similar to the problem of DDT a few decades ago and if you do not know about that issue, be sure to pick up a copy of Silent Spring by Rachel Carson.

So what do we do about this issue? Well, there are a lot of factors that need to be taken into account. For one, gold mining is very profitable - miners are thought to make up to $1,000 per month and a good salary in Peru is about $400 per month. Another problem is that other "greener" technologies are very expensive and there is little political pressure or regulation of current practices. For now some conservation groups are working to convince miners to try other technologies, but a lot of bridges have been burned by groups going in and telling miners that they are "wrong." Work on this issue is certainly needed and hopefully someone will take up the cause with an open mind and an understanding of the complex issues surrounding gold mining in the Amazonian basin.

- Gabby