María Ribeiro da Silva, 64, spent a hot afternoon hawking a new contraption to acquaintances and friends who passed by her small grocery store on the outskirts of São Paulo, Brazil's largest city and home to more than 12 million people.
Everyone who passed by received the same invitation from her: "Come, come and see my stove. It's beautiful. I made it."
Each guest received the same explanation: "I built a real wood fire oven, with a chimney and everything. No more smoke, no more heat."
It had been almost 50 years since Ribeiro da Silva cooked with firewood. Since she arrived in São Paulo in 1974, fleeing drought, hunger and poverty in the impoverished northeast region of Brazil, she has only cooked with gas.
"I spent my childhood using firewood. We didn't have gas. We didn't have the money to have a real stove. But since I arrived in Sao Paulo … wood was in the past," she told VOA.
But with the Brazilian economy worsening, and the devastating effects of the COVID-19 pandemic on the poorest parts of the population, firewood has become the only option for millions of families like Ribeiro da Silvas'.
It was a slow and gradual process for Ribeiro da Silva. First, firewood was only used in extreme cases when the gas ran out and there was not enough money to replace it. But when she lost her job as a cleaner at a company in downtown São Paulo six months ago, firewood became the primary fuel to cook food.
"Now, I only use the gas stove for simple things like making coffee or heating the food I cooked on firewood. I don't have any more money to buy gas. The price is too high. It's impossible," she said.
Skyrocketing fuel prices
According to data from the Brazilian Institute of Geography and Statistics, at least 25% of the Brazilian population is using wood as their primary cooking source.
This was before the onset of the COVID-19 pandemic.
"Due to the pandemic, the Brazilian Statistical Institute stopped carrying out quarterly in-person surveys, so we don't have data for 2020 and 2021," said Adriana Gioda, a professor in the department of chemistry at Pontifical Catholic University of Rio de Janeiro and a leading researcher on firewood consumption by Brazilian families.
"But since 2016, when the federal government cut subsidies for residential gas and tied the fuel price policy to the international prices, there has been a steady growth in the use of firewood to make food," she told VOA.
Fuel prices have been rising steadily over the past five years but have skyrocketed since President Jair Bolsonaro took office in 2019. He promised not to interfere with the country's state oil company and allow fuel prices to follow the international market.
This year alone, the price of residential gas rose by an average of 35%. Liquefied petroleum gas is the primary fuel for food production in Brazil, and its cost is linked directly to the price of the oil barrels.
'Back in time'
"In the interior of Brazil, in rural and more isolated areas, using firewood is a tradition. But what impressed us most is that the use of wood is advancing precisely in the most urban areas, in large Brazilian cities, such as Rio de Janeiro and São Paulo," Gioda said.
And it is rising in areas such as Jardim Marajoara, a poor neighborhood of migrants from the northeast region of Brazil on Sao Paulo's outskirts, where Ribeiro da Silva lives. It is in these regions that the poorest and those most affected by the economic crisis are concentrated.
Juarez Viana, a bus driver who also lost his job during the pandemic, has turned to firewood to cook. He, like Ribeiro da Silva, lives in a suburb of São Paulo that is sprawling into the last green areas of the city. Once a week, he crosses the street and enters a small forest to fetch wood.
"It's hard work, and it seems like I've gone back in time," said Viana, who is also a migrant from the Brazilian northeast. At 49, he remembers cooking with wood as a child. "But it's worth it. We do not have more money to buy gas. The price is out of control. I've never seen anything like this."
"We are going back in time, going back at least half a century," said pulmonologist Elie Fiss, a research director at Hospital Alemão Oswaldo Cruz. "Since the 1960s, we no longer saw respiratory problems related to the use of firewood for cooking. But with so many people going back to the firewood, this is a problem that will soon return to hospitals."