How a leading Brazilian researcher with deep ties to Canada is helping rewrite his country’s rules to protect one of its most precious resources

WHEN THE LARGE DAM holding back iron ore tailings from the Samarco mine in the district of Bento Rodrigues in the state of Minas Gerais in southeastern Brazil ruptured on Nov. 5, 2015, the local devastation was immediate. Sixty-two million cubic metres of toxic metal waste and a wall of mud poured into the nearby Doce River, flooding a village and killing 19 people.

From there, the contaminated stew of tailings and mud flowed downstream, wreaking havoc as the worst environmental disaster in Brazil’s history. In two weeks, it reached the river’s estuary in the state of Espirito Santo, about 650 kilometres northeast of Rio de Janeiro, and began to enter the Atlantic Ocean.

Image above: Adalto Bianchini (second right) reporting on marine polluting in a presentation to the Chico Mendes Institute for Biodiversity Conservation in Brasilia

That’s when Adalto Bianchini got a call from the Chico Mendes Institute for the Conservation of Biodiversity, an independent agency linked to Brazil’s Ministry of Environment. A professor at the Institute of Biological Sciences at the Federal University of Rio Grande in the state of Rio Grande do Sul, Bianchini has emerged as the country’s pre-eminent aquatic toxicologist and water-monitoring expert. Notably, key aspects of his expertise and influence are the product of a just-completed, seven-and-a-half-year International Development Research Centre research project.

That work involved two related applications: developing state-of-the-art models to predict levels of toxic metals in Brazilian coastal waters, and identifying and monitoring appropriate biomarkers (cell-and-tissue-level biological reactions to environmental conditions) in aquatic species to determine when dangerous contamination thresholds are reached. Such tools can be used to devise management strategies to guide industrial development and safe water use — exactly the help the Chico Mendes Institute for the Conservation of Biodiversity asked Bianchini to bring to bear on the country’s now-polluted coast.


Bianchini monitored the water and found high levels of metal contamination in a key fishery. The government responded by closing the coastal and estuarine area of Espirito Santo state to all fishing until further monitoring by Bianchini’s research group determines it’s safe.

According to biologist Chris Wood, Bianchini’s Canadian IDRC research partner, such responsibility and recognition reflects a broader achievement. “What Adalto’s really done is build a foothold for a modern, scientific approach to water quality in Brazil,” says Wood, former Canada Research Chair in Environment and Health at McMaster University and now an adjunct professor in the department of zoology at University of British Columbia.

Mud flowing in the Doce River after the Samarco dam failure caused extensive damage in the marine zone where it enters the Atlantic Ocean

Mud flowing in the Doce River after the Samarco dam failure caused extensive damage in the marine zone where it enters the Atlantic Ocean

In most of the developed world, toxicity modelling and biomarker technologies are widely used to set water policy and pollution regulations. That’s not the case in Brazil, says Bianchini. “The regulatory approach here only takes into account the concentration of pollutants in the water. Often, this results in situations where we have mass fish mortality yet when we check the chemical measurements they are within the regulatory limits.”

This gap was the motivation for Bianchini’s IDRC research. “We wanted to develop biomarkers to show that it’s necessary to include the biological component in regulations,” he says.

HIS MODELLING WORK USED the biotic ligand model, a common tool in aquatic toxicology designed to examine metals in water to determine how likely they are to accumulate at lethal levels in fish and other organisms. “We did field trips collecting samples over several years at different locations in the southern part of Brazil, trying to select the best monitoring species,” says Bianchini, “and from those, we selected the best biomarkers to apply to contamination by pesticides, hydrocarbons, metals and personal care products — the new class of contaminants.”

Bianchini then began educating government officials on the findings. His goal: to see water-testing rules and planning and development guidelines rewritten based on his work.

The first to update its rules was the environmental secretariat in his local Rio Grande municipality. Bianchini hopes for broader uptake soon. “We did our final workshop in April with the 10 different municipalities that cover the three main water basins for southern Brazil, about 700 kilometres by 700 kilometres,” he says.

Bianchini says several large companies have also agreed to start testing his approach in their operations. One is the Rio Grande do Sul state water supply company, CORSAN. Another is Petrobras, the Brazilian multinational petroleum company.

Ultimately, however, he is in some ways proudest of the impact the IDRC-funded work has had on educating and training Brazilian students and building local capacity to take this science and its applications forward. “We now have a new generation more concerned about environmental preservation and care of aquatic systems,” he says. “And they’re more skilled as well.”

This article was originally published in September 2017 on the Charting Change website, published jointly by Canadian Geographic and Canada’s International Development Research Centre. Photos courtesy of Brazilian NR (top) and Marcelinho