In 2015, Colombia became the last country in the world to suspend the fumigation of crops with glyphosate, after 15 years of use.

Colombia started fumigating crops with glyphosate again, the government announced Wednesday, after the technique was suspended in 2015 over health and environmental concerns.

The fumigations began on Jan. 2, said Defense Minister Luis Carlos Villegas at a press conference, adding the fumigation of the controversial Monsanto-produced herbicide was focused in the northern province of Catatumbo and the southeastern provinces of Nariño and Putumayo. Unlike previous fumigation, which was aerial, the new coca erradication plan consists of manual, land-based spraying.

Launched in 1994, the spraying program was long treated as sacrosanct by Colombian officials, who gladly accepted billions of dollars in funding from Washington to fumigate farmland throughout the countryside, often spraying all crops, leaving campesinos with no livelihood.

But after the World Health Organization warned in March 2015 that glyphosate was "probably carcinogenic," Santos' Cabinet suspended the air fumigations. Colombia became the last country in the world to suspend aerial fumigations of glyphosate, after 15 years of use.