Kenyan agronomists and coffee marketing agents have raised the red flag over the use of a weed killer suspected to cause cancer.
The two parties say 2,4-D and Bayer’s Roundup, which are used to eliminate weeds in coffee, tea and sugarcane among other crops, are harmful to human health.
“The country risks losing international market for some of its cash crops due to continued use of such herbicides like 2,4-D and Roundup believed to cause life threatening diseases like cancer,” cautioned Kamau Kuria, Managing Director, Coffee Management Services Mills.
Countries such as the US, Germany, Japan and Switzerland, he said, have warned against importation of crops in which such banned herbicides have been used to control weeds.
“It is vital for farmers to use herbicides approved by the pesticides control board and where necessary take soil samples to the Kenya Plant and health Inspectorate services to determine whether it has been contaminated by the herbicides,” said Mr Kuria.
According to World Health Organisation (WHO), the widely used 2,4-D – a key ingredient in a new herbicide developed by the Dow company – “possibly” causes cancer in humans.
The classification of the weed killer, 2,4-dichlorophenoxyacetic acid, was made by the WHO’s International Agency for Research on Cancer (IARC).
The IARC said it reviewed the latest scientific literature and decided to classify 2,4-D as “possibly carcinogenic to humans”, a step below the more definitive “probably carcinogenic” category but two steps above the “probably not carcinogenic” category.
IARC’s findings on 2,4-D have been awaited by environmental and consumer groups that are lobbying US regulators to tightly restrict the use of 2,4-D.
IARC said it decided on the “possibly” classification because there was “inadequate evidence in humans and limited evidence in experimental animals” of ties between 2,4-D and cancer.
It said that epidemiological studies provided “strong evidence that 2,4-D induces oxidative stress … and moderate evidence that 2,4-D causes immunosuppression”.
Mr Kuria, who made the remarks during field day for coffee farmers at CMS Mills in Eldoret, asked Kenyan farmers to avoid the chemical.
“Some of these herbicides remains in the soil for long period and requires a lot of rainfall to be washed away or filter causing some health risks,” he said.
A team from Japan Coffee Association (JCA), he said, visited Kenya recently on a fact-finding mission to ascertain if farmers were still using banned herbicides.
Some agronomists confirmed that some of the herbicides, including 2,4-D and Roundup, are harmful to human health and farmers should exercise extra caution when handling them.
“Farmers need to be extra cautious when handling the chemicals and if possible stop using them altogether,” said David Koskei, an agronomist in Eldoret.
The United States Environment Protection Agency (EPA) has however given Roundup weed killer a clean bill of health saying it does not cause cancer, a ruling that has been disputed by environmental advocates including the National Resources Defence Council (NRDC).
The agency said its findings were consistent with those of ‘many countries and other federal agencies.
Many farmers in the North Rift region maintain that Roundup is safe weed killer despite ruling by a US court that it causes skin or blood cancer.
They argue that the herbicide was effective for weed control and they have never experienced any health effects for the many years they have been applying before planting their crops.
“I have no idea that the herbicide is hazardous to human health. A small quantity of the chemical is enough to wipe out weeds making it more cost effective as compared to other chemicals,” said James Too from Chepkumia, Nandi County.
He uses the chemical to kill weeds in his tea and maize plantation and apply the herbicide once a month on the crops.
Like other farmers in the region, he has never heard about the US court ruling.
The sentiments are shared Agronomist George Otieno of Agri-Tech firm who argues that the herbicide has no health effects so long as one observes the specified instructions when using it.
“The herbicide has been in the market for decades and I have never heard of anyone who has developed respiratory, skin or any other health problem as a result of use of this chemical,” said Mr Otieno.
He however admits that some livestock have died after feeding on silage or grass sprayed with Roundup.
“I have witnessed situations where some farmers have lost their livestock after feeding on grass contaminated with Roundup. But that is as a result of negligence and farmers need to protect areas sprayed with the chemical,” said Mr Otieno.