Scientists have linked the exceptionally high rates of throat cancer in the county to the local soils.

Their study has confirmed that residents with high levels of selenium, a nutrient found in soil, also have high prevalence of throat cancer.

But this, the scientists say, is the opposite of what has been found elsewhere with people having low levels of selenium normally at highest risk of throat cancer.

“We found a positive association between higher serum selenium concentration and prevalence of throat cancer, an association contrary to our original hypothesis,” say the scientists who call for more investigations.

The study which involved 294 adults recruited within a 5km radius of the Tenwek Mission Hospital, at Bomet Township, Kaganaiti, Koiwa and Mogogosiek, was published on Friday (8th December) in the journal BMC Cancer.

This is one of several global efforts to understand the cause for high rates of throat cancer in Bomet and surrounding areas.

It involved researchers from Tenwek Mission Hospital in Bomet,  the US National Cancer Institute, University of Missouri, US and Mayo Clinic, US.

Kenya belongs to the African Esophageal Cancer Corridor (ESCC) which has the highest incidence of throat cancer in the world.

The corridor includes Malawi, Kenya, Uganda, Tanzania and parts of South Africa while other areas with high throat cancer incidence are China and Iran.

Various reports now indicate Kenya to have the highest rates of throat cancer in the world with Bomet and Eldoret increasingly seen as a significant hotspot.

Unlike elsewhere, throat cancer in the Rift Valley has also been seen to affect younger people and both genders in equal numbers.

Aflatoxins in food, traditional grain alcohol and mursik, the traditional fermented milk of the Kalenjin, have been blamed for the high rates of throat cancer in the region.

But researchers say this does not tell the whole story hence the new study on selenium.

Several studies in China, Finland and elsewhere had found people with low levels of selenium to be at high risk of cancer suggesting if they increased intake they may be protected against cancers. [www.rocketscience.co.ke]