LIMPIO, Paraguay — The Cerro Lagoon in the Paraguayan city of Limpio is sharply divided into two parts: one purple, one blue. One part emits a foul odor, the other doesn’t.
The lagoon was split by construction of a roadway to carry trucks to and from local factories. Several months ago, residents began noticing that the water on one side of the roadway was changing color, they went to local environmental authorities who took water samples.
A technician at the National University Multidisciplinary Lab said Wednesday that the color of the water is due to the presence of heavy metals like chromium, commonly used in tanning animal skins to produce leather.