Rising cases of cervical cancer in Kenya have been linked to consumption of food, especially maize, that is contaminated with aflatoxin.
A study carried out among women at Moi Teaching and Referral Hospital (MTRH) in Eldoret suggests consumption of aflatoxin in food increases the risk of cervical cancer.
The rate of aflatoxin contaminated food, especially in maize and milk, has been on the increase in Kenya and so have been cases of cervical cancer.
Cervical cancer, the second most common cancer in women after breast cancer, is the leading cause of cancer-related deaths in the country.
The cancer caused by Human Papilloma Virus (HPV) and transmitted through sex killed 5,250 women last year and if not checked it is estimated it will take away 6,000 lives by 2025.
The new study published last Thursday in the journal Open Forum Infectious Diseases, found women with high aflatoxin concentrations in their blood were also likely to have cancer causing HPV strains.
Cervical cancer is caused by various types of HPV and while found in many women only in a minority does it lead to cancer.
This fact prompted the investigators from MRTH, Indiana University, US, Moi, Eldoret, Maseno universities and Johns Hopkins University, US, to search for possible triggers.
One suspect trigger, the investigators suggest, was aflatoxin for its known role in the development of liver cancer and suppression of human immunity.
The researchers recruited 86 women from 285 attending a cervical cancer screening programme at MTRH in 2015 and 2016.
The recruited women aged 18 to 45 who were living within 30km of Eldoret town, were followed for up to four years.
The researchers collected cervical swabs for HPV testing at Kenya Medical Research Institute. Also collected were blood samples for aflatoxin testing at Johns Hopkins University in the US.
Forty nine or 57 per cent of the women tested positive for aflatoxin, a group that was also detected with cancer causing HPV types.
The study by among others Jianjun Zhang of Indiana University and Omenge Orang’o of Moi University says women detected with aflatoxin in their blood also had cancer causing HPV strains.
“Aflatoxin plasma concentrations were associated with an increased risk of cancer causing HPV detection, …. which may increase the cancer risk,” said the study.
Now the researchers want more studies carried out to determine the actual mechanism, how the aflatoxin could be working with HPV to increase the risk of cervical cancer.
“Further studies are needed to determine if aflatoxin interacts with HPV in a synergistic manner to increase the risk of cervical cancer.”
The investigators suggest consumption of food highly contaminated with aflatoxins, especially maize may be the source of exposure among women.
“More than four billion people are exposed to aflatoxins in their foods, mainly maize and ground nuts and mainly in Sub Saharan Africa,” says the study.
A recent extensive survey by the Nairobi-based International Livestock Research Institute (ILRI) confirmed high levels of aflatoxin contamination in Kenyan’s popular staples including maize, milk and sorghum.
In a raft of 12 studies, the scientists had confirmed excessive presence of aflatoxin in milk and maize, sorghum and millet flours as well as in animal feeds.
In Nairobi aflatoxin was detected in all milk and sorghum samples and 95 per cent of the maize.
Of these, 63 per cent of the milk samples, 16 per cent of maize and one per cent of sorghum exceeded allowable levels by the European Union
The researcher had had also collected milk and livestock feed concentrates from 285 dairy farmers in Kwale, Isiolo, Tharaka-Nithi, Kisii and Bungoma counties and analyzed them for aflatoxin.
They found between 50 per cent and 90 per cent of cattle feed contaminated with aflatoxins way above levels allowable by the World Health Organisation.
About 83 per cent of the feeds from retailers and 28.6 per cent to 100 per cent of the feeds from manufacturers exceeded the WHO limit.
To avoid a catastrophe, the researchers advocated regulators adopt zero tolerance of aflatoxin contaminated food and feeds in the market.
“Farmers, traders and households must be educated on the dangers and how to reduce aflatoxin contamination especially in wet seasons,” the researchers said.