The Valley of Death
In the early 1980s, the industrial city of Cubatão was known as the "Valley of Death". Its location, located between the Serra do Mar coastal mountains and the Atlantic Ocean, created a natural trap for airborne pollutants. The city housed a massive industrial complex, including one of Brazil's largest petroleum refineries, a steel plant, and numerous chemical and fertilizer factories.
These industries released more than 1,000 tons of toxic chemicals into the air every day. Pollutants included sulfur dioxide, ammonia, benzene, and heavy metals. The air was so corrosive it damaged metal structures. Acid rain stripped the vegetation from the slopes of the Serra do Mar, leading to landslides on the bare earth. The local infant mortality rate was one of the highest in Brazil, with a significant number of children born with anencephaly, a fatal condition of being born without parts of the brain and skull. One shantytown, Vila Parisi, was known for clusters of birth defects and respiratory disease.
A catastrophic event on February 25, 1984, brought the crisis to a head. A leaking Petrobras pipeline spilled approximately 700,000 liters (185,000 gallons) of gasoline into the mangrove swamp under the Vila Socó shantytown. The resulting fire incinerated a large part of the community. The official death toll was 93, but unofficial estimates are much higher.
The Cleanup and Recovery
In response to the growing crisis and public pressure, the São Paulo state environmental agency, CETESB, launched the Cubatão Pollution Control Program in 1983. The project, financed partly by the World Bank, aimed to bring 320 major pollution sources under control. Industries were required to install filters and wastewater treatment systems to curb their emissions.
The results were swift and measurable. By 1988, ammonia releases had been reduced by 97%, particulate emissions by 92%, and sulfur dioxide by 84%. In total, 98% of industrial pollutants were brought under control. The total cost of the cleanup efforts eventually exceeded $1.2 billion.
With the reduction in pollution, the local ecosystem began to show signs of recovery. Reforestation projects replanted native trees on the scarred hillsides. After a 20-year absence, fish returned to the local rivers, which were dredged to remove contaminated sediment. The United Nations, which had once singled out Cubatão as a example of industrial pollution, later called it an example of environmental recovery. The city's air and water quality improved, demonstrating that even severely degraded environments can be restored with concerted effort and investment.