The severity of the effects depends on factors such as the type of element, dose, age, duration and route of exposure. In the case of the Caquetá River, the cause of the exposure is the consumption of fish contaminated by the excessive use of mercury to separate the sand from the gold in mining activities.
When the mercury has been used, it is dumped into water, where it is transformed into methylmercury (an organic and neurotoxic form of mercury) and absorbed by fish that are then consumed as part of the diet of populations who live by the riverbed.
What are the effects of exposure to high levels of mercury?
Although almost all fish have a small level of mercury, when the concentration level exceeds the recommended maximum limits (more than 0.5 μg/gr according to the World Health Organisation and the European Commission) it can have serious health effects. Especially for very vulnerable groups such as pregnant women, growing children and subsistence fishers.
Two of the recommendations to reduce the levels of exposure to mercury are, in the case of breastfeeding mothers, to instead not breastfeed their children, and in the case of the rest of the community, to reduce their consumption of fish.
These two measures, while they may be effective in preventing health impacts, must be temporary while definitive measures are taken to stop the causes of the problem. Communities have the right to maintain their cultural practices and diet based on traditional fishing, and both mothers and children have the right to have breastfeeding fully guaranteed.
How is the use of mercury regulated in Colombia?
Mercury is used as raw material in several industrial processes; therefore, its importation and commercialization is permitted under control guidelines established in Resolution 130 of 2017. This regulation also created a register for authorized importers and traders.
However, a study published by the Gaia Amazonas Foundation in 2018 revealed that a large proportion of the mercury that enters the country legally ends up being used in illegal mining activities. For example, in 2017, of the 118.8 tons of mercury legally imported, at least 50% was diverted for this purpose.
In this context, the implementation of the Minamata Convention, ratified by Colombia on August 26th, is especially important. The objective of this international treaty is to definitively eliminate the use of mercury in all manufacturing sectors. The goal set by the national government is that by 2023 the use of mercury in Colombia will be completely suspended.
What is the protective appeal for?
The appeal has become a powerful tool to protect the rights of indigenous communities and to apply innovative concepts such as the recognition of rights to nature. An important case that combines both objectives is the recent ruling that declared the Colombian Amazon as a rights-holding area.Print