A new study published in Science of the Total Environment reports heavy contamination around Lake Junín. The lake basin sits at 4,100 meters and is the source of the Mantaro River. Researchers tested more than 200 surface soil samples and measured 14 heavy metals, metalloids and trace elements.
The study found that 99 per cent of the area has "very high to ultra-high" ecological risk. It reports a "100 per cent carcinogenic risk" for adults, and says children are highly exposed to arsenic. In agricultural areas some toxins exceed ecological thresholds by more than 100 times.
Local pollution is linked to old abandoned mines, agriculture and urbanisation. About 50,000 people live in the area and water use from the basin reaches 1.3 million people downstream. The authors say more work is needed to measure the full impact, especially on children and pregnant women.
Difficult words
- contamination — the act of making something dirty or unsafe
- arsenic — a harmful chemical element
- lead — a heavy metal that is harmful to health
- cadmium — a toxic metal found in some polluted areas
- exposed — being in a place where something is dangerous
- health — the state of being free from illness
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- Why is contaminated water a problem for communities?
- How can people protect themselves from these toxins?
- What steps can be taken to clean up bodies of water like Junín Lake?
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