It was an unprecedented event that covered major cities as Buenos Aires and Rosario in smoke, affecting the health of millions of people.

[1][2] Intentional fires started in April 2008, following the purpose of burning grasslands to adapt the De la Plata Basin wetlands land for a livestock grazing use.

[2] The cloud of smoke that followed the fires caused the worst air pollution in Argentinean history, reaching even Montevideo, Uruguay and forcing airport and highway closures.

[3] A significant increase in ocular symptoms and bulbar conjunctival hyperemia, as well as tear film instability was also proven.

The fires were located in the Paraná Delta islands, part of the Río de la Plata Basin, which ranges from the Entre Ríos to Buenos Aires provinces in Argentina, comprising over 380,000 ha.