Background: Geophagy, a form of pica, is the deliberate consumption of soil and is relatively common across
Sub-Saharan Africa. In Tanzania, pregnant women commonly eat soil sticks sold in the market (pemba), soil from
walls of houses, termite mounds, and ground soil (kichuguu). The present study examined geophagy practices of
pregnant women in a gold mining area of Geita District in northwestern Tanzania, and also examined the potential
for exposure to chemical elements by testing soil samples.
Method: We conducted a cross sectional study using a convenience sample of 340 pregnant women, ranging in
age from 15–49 years, who attended six government antenatal clinics in the Geita District, Tanzania. Structured
interviews were conducted in June-August, 2012, to understand geophagy practices. In addition, soil samples taken
from sources identified by pregnant women practicing geophagy were analysed for mineral element content.
Results: Geophagy was reported by 155 (45.6%) pregnant women with 85 (54.8%) initiating the practice in the first
trimester. A total of 101 (65%) pregnant women reported eating soil 2 to 3 times per day while 20 (13%) ate soil
more than 3 times per day. Of 155 pregnant women 107 (69%) bought pemba from local shops, while 48 (31%)
consumed ground soil kichuguu. The estimated mean quantity of soil consumed from pemba was 62.5 grams/day.
Arsenic, chromium, copper, iron, manganese, nickel and zinc levels were found in both pemba and kichuguu
samples. Cadmium and mercury were found only in the kichuguu samples. Based on daily intake estimates, arsenic,
copper and manganese for kichuguu and copper and manganese for pemba samples exceed the oral Minimum Risk
Levels designated by the U.S. Agency for Toxic Substance and Disease Registry.
Conclusion: Almost 50% of participants practiced geophagy in Geita District consistent with other reports from
Africa. Both pemba and kichuguu contained chemical elements at varying concentration, mostly above MRLs. As
such, pregnant women who eat soil in Geita District are exposed to potentially high levels of chemical elements,
depending upon frequency of consumption, daily amount consumed and the source location of soil eaten.