Brazil Can Cut Wheat Carbon Footprint by 38%, Study Finds

A groundbreaking study by Embrapa has shown that wheat produced in Brazil emits less carbon than the global average — and that emissions could be cut even further. Conducted in Southeast Paraná, the research revealed that adopting existing sustainable practices and technologies could reduce greenhouse gas emissions from wheat production by up to 38%.

Published in the Journal of Cleaner Production, the study is the first in South America to estimate the carbon footprint of wheat from farm to flour, and the first globally in a subtropical region. Brazil’s wheat production averaged 0.50 kg of CO₂ equivalent per kilogram — lower than the global average of 0.59 kg.

Researchers analyzed data from 61 farms during the 2023/2024 season and tracked the entire milling process in a local facility. The assessment included inputs like fertilizers and pesticides, as well as post-harvest stages such as transport, drying, and flour production, according to a press release.

The study identified nitrogen fertilizers as the largest contributor to wheat’s carbon footprint, with urea being the main culprit. Urea application leads to significant nitrous oxide (N₂O) emissions — accounting for up to 40% of the greenhouse gases linked to wheat production. Despite its popularity due to low cost, urea’s environmental impact is high.

Researchers found that replacing urea with calcium ammonium nitrate (CAN) could reduce carbon emissions by 4%, helping lower the crop’s overall environmental footprint. This switch could also ease soil acidification, another major environmental concern in wheat farming.

“When urea is not fully absorbed by plants or is leached as nitrate, reactions occur that release hydronium ions, increasing soil acidity. On the other hand, CAN-based fertilizers help neutralize this effect due to their calcium content,” explains Embrapa Meio Ambiente (SP) researcher Marília Folegatti.

Folegatti notes that reducing reliance on synthetic fertilizers will require a broader adoption of alternative technologies, including biofertilizers, biopesticides, slow-release fertilizers, and nanofertilizers. She also highlights ongoing research into producing green urea and ammonium nitrate using renewable energy sources.

Maria Cléa Brito de Figueiredo, a researcher at Embrapa Agroindústria Tropical (CE), adds that nitrogen fertilizers are also the main source of greenhouse gas emissions in other crops studied by Embrapa, such as tropical fruits — including mango, melon, and green coconut — when analyzing both carbon and water footprints.

“In addition, the production of synthetic fertilizers generates heavy metals that contribute to soil contamination, which can affect food quality, human health and ecosystems,” warns the scientist.

The study also highlights that using higher-yield wheat cultivars can lower environmental impacts by producing more with fewer resources like land and water. Additionally, it emphasizes the need to consider other environmental factors, including biodiversity and soil health. Future research that incorporates these elements could provide a more complete picture of wheat production sustainability in tropical and subtropical regions.

Globally, the carbon footprint of wheat production ranges from 0.35 to 0.62 kg of CO₂ per kilogram of grain, depending on regional climate conditions and farming practices. The global average is estimated at 0.59 kg CO₂ per kilogram.

Brazil stands out positively in this landscape, with an average footprint of 0.50 kg CO₂ per kilogram of wheat—lower than figures reported for China (0.55), Italy (0.58), and India (0.62).

“We can still evolve. The study indicates that, with a set of adjustments, our numbers can bring us closer to references such as Australia and Germany, which have indicators close to 0.35”, evaluates Álvaro Dossa, analyst at Embrapa Trigo (RS). According to the article, in the scenarios studied, using technologies already available, the carbon footprint of Brazilian wheat can be reduced by 38%.

Globally, carbon footprint data for wheat production varies by continent, with average estimates of 0.24 kg CO₂/kg in Africa, 0.68 in Asia, 0.33 in Europe, 0.42 in North America, and 0.29 in Oceania—though wheat production there is still limited. The Embrapa study is the first to provide carbon footprint estimates for wheat in South America.

Beyond carbon emissions, the research also assessed the environmental impacts of wheat and wheat flour production on water use, soil acidification, marine and freshwater eutrophication, and toxicity — both human and ecological.

“Wheat production in Brazil has superior impacts in categories such as soil acidification and terrestrial ecotoxic toxicity, due to fertilizer and pesticide emissions. However, the results of the study suggest that, with the use of more efficient cultivars and sustainable practices, Brazilian production can consolidate among the most sustainable in the world,” says Marília Folegatti.

In other environmental categories, Brazil’s wheat production shows advantages over other countries. The use of rainfed cultivation helps significantly reduce water consumption during grain growth, lessening the impact on water bodies. However, the production of NPK fertilizers (nitrogen, phosphorus, and potassium) still contributes to water use.

Tags: Brazil, Production, wheat, fertilizers, greenhouse gas, carbon, emissions