Abstract:
Soil, water and food supply composition data have been combined to primarily estimate micronutrient
intakes and subsequent risk of deficiencies in each of the regions studied by generating new data to
supplement and update existing food balance sheets. These data capture environmental influences,
such as soil chemistry and the drinking water sources to provide spatially resolved crop and drinking
water composition data, where combined information is currently limited, to better inform intervention
strategies to target micronutrient deficiencies. Approximately 1500 crop samples were analysed,
representing 86 food items across 50 sites in Tanzania in 2013 and >230 sites in Western Kenya between
2014 and 2018. Samples were analysed by ICP-MS for 58 elements, with this paper focussing on calcium
(ca), copper (cu), iron (fe), magnesium (Mg), selenium (Se), iodine (i), zinc (Zn) and molybdenum (Mo).
in general, micronutrient supply from food groups was higher from Kilimanjaro,tanzania than counties
in Western Kenya, albeit from a smaller sample. for both countries leafy vegetable and vegetable
food groups consistently contained higher median micronutrient concentrations compared to other
plant based food groups. Overall, calculated deficiency rates were <1% for Cu and Mo and close to or
>90% for Ca, Zn and I in both countries. For Mg, a slightly lower risk of deficiency was calculated for
Tanzania at 0 to 1% across simplified soil classifications and for female/males, compared to 3 to 20% for
Kenya. A significant difference was observed for Se, where a 3 to 28% risk of deficiency was calculated
for Tanzania compared to 93 to 100% in Kenya. Overall, 11 soil predictor variables, including pH and
organic matter accounted for a small proportion of the variance in the elemental concentration of
food. Tanzanian drinking water presented several opportunities for delivering greater than 10% of the
estimated average requirement (EAR) for micronutrients. For example, 1 to 56% of the EAR for I and up
to 10% for Se or 37% for Zn could be contributed via drinking water