Who does not have a mobile, a tablet and even an electric car? Who does not complain when their electronic devices start to charge worse and decrease the durability of their batteries? How often do we change our electronic devices? But who knows how and where the materials needed to make these batteries come from? Who knows what happens to the devices we throw away?
The electronic devices that we all have are a complex mix of hundreds of materials. Among which are heavy metals such as lead, mercury or cadmium. To give you an idea, a mobile phone has between 500 and 1,000 different compounds. In addition, it should be known that obtaining these materials puts the health of the workers who extract the metals in the mines and manufacture the products at risk. And at the end of their useful life, if these materials are not properly treated, the dangerous substances they contain can pollute the environment and affect people’s health.
The vicious circle of electronic devices
Most of the metals needed for the production of electronic devices are mined in developing countries, such as Africa. Once obtained, they are bought by large Asian companies to produce the components of electronic devices. Eventually, the smartphones, tablets and electric cars produced will be sold all over the world. Although most consumers will live in developed countries, such as North America and Europe.
But this is not all. When our electronic devices are obsolete and their batteries do not last long enough, the heavy metal journey that began in the African mines ends with the sending our electronic waste back to the African continent.
Rich countries will pay poor countries to take care of their garbage, which is an important part of their economy. But causing a great environmental problem, since recycling in these areas is not sufficiently developed.
The case of the Ghana landfill
As an example, in Ghana, a West African country, there is one of the largest e-waste landfills in the world, and receives mainly European electronic waste. In this landfill, technological waste accumulates to be subsequently burned.
These wastes can begin to decompose, producing gases that go into the atmosphere and liquids that will penetrate the ground. Its burning will also emit dangerous gases that pass into the atmosphere. Previous studies have already shown that Ghana’s e-waste landfill causes a major soil contamination and the atmosphere by heavy metals. However, local populations are unaware of the environmental problems that these electronic waste produce, breathing these gases and consuming the natural resources of the surroundings. There is no prior sanitary control.
Pollution returns to Europe
The return of European electronic waste to African countries closes a circle that is a clear example of current global politics: the first world extracts what it needs and returns what it no longer wants.
The enormous environmental cost of the metals needed to meet the growing need for electrical and electronic devices in developed countries is being paid by waste producing and receiving countries in Africa. Meanwhile, European states benefit from new gadgets and green carbon-free transport thanks to electric cars that have African minerals in their batteries. But perhaps that circle is not perfect and this pollution is reaching European citizens. Seafood could be a possible vector of heavy metal contamination between Africa and Europe.
Heavy metals produced in mining areas and in e-waste dumps reach coastal waters through rivers and streams and accumulate in marine sediments. From there, they will enter the food chain through plankton. Then they will pass to the fish that consume that plankton, finally ending up in the large predators. The accumulation of these polluting metals will depend on the species, depending on their trophic level, their life history and their feeding habits.
Tunas with high levels of heavy metals
An example of a highly predatory fish that accumulates heavy metals is tuna. This fish is not advisable for children and pregnant women due to its high mercury content. The presence of metals in these fish depends on the species, sex and the area in which it develops.
Fish caught in African waters enters world trade and can be sold anywhere, appearing on the European market. The sustainable fisheries partnership agreements Union vessels allow Union vessels to catch tuna while migrating along African waters. Therefore, if African heavy metal pollution reaches tuna in the open ocean through river plumes and the food chain, Europe could be consuming the heavy metal pollution through ingesting marine species caught in African waters. .
What would we obtain if we analyzed tunas from different fishing areas and marketed in Spain? Would the metals extracted in African mines, present in electronic waste, be concentrated in tunas from African waters?
The answer is yes. The results of a study we recently published show higher concentrations of all the metals analyzed in tunas caught in African waters, especially mercury and lead.
Furthermore, the concentrations of metals in tunas are related to the concentrations found in the waters where they were caught, showing that the fish are incorporating the metals present in the environment in which they live.
What can we do?
Now that we know that the ocean gives us back everything we send it, and that it may be damaging our health, what can we do?
These are some examples of courses of action:
- Study in depth how metal pollution passes from rivers and land to the sea.
- Study in depth how these metals accumulate in the marine food chain.
- Study the risk of ingesting heavy metals through the consumption of seafood contaminated with metals from mining and electronic waste.
- Educate in a responsible consumption of electronic devices, making known the origin and treatment of derived waste.
- Work towards the improvement in the treatment of electronic waste in the producing and importing countries.