Human aflatoxin exposure in Kenya, 2007: a cross-sectional study

Abstract

Aflatoxins contaminate approximately 25% of agricultural products worldwide. They can cause liver failure and liver cancer. Kenya has experienced multiple aflatoxicosis outbreaks in recent years, often resulting in fatalities. However, the full extent of aflatoxin exposure in Kenya has been unknown. Our objective was to quantify aflatoxin exposure across Kenya. We analysed aflatoxin levels in serum specimens from the 2007 Kenya AIDS Indicator Survey – a nationally representative, cross-sectional serosurvey. KAIS collected 15,853 blood specimens. Of the 3180 human immunodeficiency virus-negative specimens with ≥1 mL sera, we randomly selected 600 specimens stratified by province and sex. We analysed serum specimens for aflatoxin albumin adducts by using isotope dilution MS/MS to quantify aflatoxin B1-lysine, and normalised with serum albumin. Aflatoxin concentrations were then compared by demographic, socioeconomic and geographic characteristics. We detected serum aflatoxin B1-lysine in 78% of serum specimens (range = <LOD-211 pg/mg albumin, median = 1.78 pg/mg albumin). Aflatoxin exposure did not vary by sex, age group, marital status, religion or socioeconomic characteristics. Aflatoxin exposure varied by province (p < 0.05); it was highest in Eastern (median = 7.87 pg/mg albumin) and Coast (median = 3.70 pg/mg albumin) provinces and lowest in Nyanza (median = <LOD) and Rift Valley (median = 0.70 pg/mg albumin) provinces. Our findings suggest that aflatoxin exposure is a public health problem throughout Kenya, and it could be substantially impacting human health. Wide-scale, evidence-based interventions are urgently needed to decrease exposure and subsequent health effects.

Longitudinal evaluation of aflatoxin exposure in two cohorts in south-western Uganda

“…If taking their proposed 4.6 conversion, the AFB-Lys adduct level in our study using GPC study samples is similar to that of Asiki et al (2014). The averaged adduct level is actually higher than the levels found in children from Kikelelwa, Tanzania (0.78 pg mg −1 albumin after conversion by division of 4.6) (Shirima et al 2013;Yard et al 2013). However, the adduct level is still lower than averaged levels found from neighbouring countries, such as Kenya and Tanzania, and West African countries, such as Ghana, Gambia, Benin and Togo (Gong et al 2002(Gong et al , 2012Ofori-Adjei 2012;Shirima et al 2013).…”

“…Compared with other African countries, the averaged AFB-Lys level found in this study was among those lower levels reported. Yard et al (2013) suggested that the estimated AFB-Lys adduct values from the ELISA method is typically 4.6 times higher than that from the HPLC-fluorescence measurement. If taking their proposed 4.6 conversion, the AFB-Lys adduct level in our study using GPC study samples is similar to that of Asiki et al (2014).…”

“…Human exposure to AF and its linkage to adverse health effects in various human populations have been well studied in some West African countries (Williams et al 2004(Williams et al , 2010, as well as in Kenya (AzzizBaumgartner et al 2005;Lewis et al 2005;Yard et al 2013), a neighbouring country to Uganda. However, no human exposure studies have ever been assessed in Uganda with the exception of an earlier pilot investigation in small numbers of children and a recent pilot study (Wild et al 1990;Asiki et al 2014), although a link between AF and hepatoma was suggested decades ago in Uganda (Alpert et al 1968(Alpert et al , 1971Serck-Hanssen 1970).…”

Aflatoxinas en Alimentos Y Exposición Dietaria Como Factor De Riesgo Para El Carcinoma Hepatocelular

“…Debido a la alta prevalencia de casos de aflatoxicosis documentados en el país, en el 2013 se cuantificó la exposición de aflatoxinas a través de un estudio serológico y epidemiológico transversal. Se detectaron aductos de AFB1 en el 78% de las muestras de suero y se concluyó que la exposición a aflatoxinas es un problema de salud pública en Kenia, el cual puede generar impacto en la salud humana (70).…”

Biomarker der internen Exposition gegenüber toxikologisch relevanten Kontaminanten in Lebensmitteln

“…In einer Querschnittstudie mit 600 Probanden in Kenia wurde AFB1-Lys in 78 % aller Blutproben mit Werten zwischen 0,02 (Detektionslimit) und 9,52 ng AFB1-Lys/ml detektiert. Im Gegensatz dazu zeigten nur 1,3 % aller Blutproben von 2104 US-Einwohnern messbare Konzentrationen von AFB1-Lys zwischen 0,02 und 0,2 ng AFB1-Lys/ml [19]. Durch Bestimmung der Lysinaddukte mittels ELISA oder LC-MS/MS wurden Zusammenhänge zwischen der Aufnahme von AFB1 und dem Auftreten von Tumoren in der Leber [20] und der Gallenblase [21] sowie einem verminderten Wachstum von Kindern gezeigt [22].…”