Kortei et al. BMC Pregnancy and Childbirth          (2020) 20:160 
https://doi.org/10.1186/s12884-020-02857-4
RESEARCH ARTICLE Open Access
Potential health risk assessment of toxic
metals contamination in clay eaten as pica
(geophagia) among pregnant women of Ho
in the Volta Region of Ghana
Nii Korley Kortei1* , Alice Koryo-Dabrah1, Papa Toah Akonor2,3 , Nana Yaw Barimah Manaphraim4,
Matilda Ayim-Akonor5 , Nathaniel Owusu Boadi6 , Edward Ken Essuman1 and Clement Tettey7
Abstract
Introduction: Geophagia although pleasurable and somewhat a necessity among pregnant women, also comes
along with its own attendant problems such as exposure to potentially hazardous substances like bacteria, fungi,
helminthes and ova, radioactive materials, and toxic elemental minerals in the soil depending on the geographical
location.
Methodology: This study evaluated the potential health risk involved during the exposure of pregnant women to
toxic elemental minerals via the consumption of clay as pica (geophagia). Elemental mineral analysis was carried
out using Buck Scientific 210VGP Flame Atomic Absorption Spectrophotometer (Buck Scientific, Inc. East Norwalk,
USA). Risk assessment methods were also used to ascertain the various risks factors and the overall risk level.
Results: Concentrations of the macro elements investigated were 1.38 ± 1.5, 2.40 ± 1.5, 7.74 ± 1.5, 4.01 ± 1.0, 13.24 ±
2.2 and 13.76 ± 2.1 mg/Kg for iron (Fe), copper (Cu), zinc (Zn), potassium (K), magnesium (Mg) and sodium (Na)
respectively. While that for the micro elements were 1.63 ± 0.03 μg/Kg, 4.72 ± 0.8, 0.53 ± 0.02 and 1.85 ± 0.3 mg/kg
respectively for arsenic (As), manganese (Mn), lead (Pb) and nickel (Ni). Estimated Daily Intake (EDI), Hazard Quotient
(HQ), Target Hazard Quotient (THQ) and Total Target Hazard Quotient (TTHQ) values ranged 0.611–5.44 (mg/kg Bw/
day), 6.26 × 10− 4 – 106.5, 0.067–10.34 and 15 respectively.
Conclusion: There is the likelihood of posing adverse health problems when clay samples obtained from Anfoega
which is sited in the Volta region of Ghana is consumed due to the fact that the HQ’s of these elemental minerals
were > 1 which points to high content of Manganese (Mn) and Nickel (Ni). It is also likely to cause adverse health
problems in an individual’s life time since THQ for Arsenic, Lead and Nickel were above 1. Ultimately, the
cumulative effect of these toxicants were exceedingly great (≤ 15) which implied a high level of unsafety
associated with this clay. Per the results from this study, it is not safe for pregnant women to consume clay as pica
since these toxic elements may cause detrimental effects on the foetus of the unborn child.
Keywords: Pica, Geophagy, Clay, Volta region, Pregnant women, Risk assessment, Ghana
* Correspondence: nkkortei@uhas.edu.gh
1Department of Nutrition and Dietetics, School of Allied Health Sciences,
University of Health and Allied Sciences, PMB 31, Ho, Ghana
Full list of author information is available at the end of the article
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Kortei et al. BMC Pregnancy and Childbirth          (2020) 20:160 Page 2 of 7
Background use of kaolin (a form of clay) to treat diarrhoea and im-
Pica is universally described as the obstinate ingesting of prove upon bioactivities [11]. A similar phenomenom
substances that provide no nutrients and is aptly catego- was demonstrated by Ngole et al. [17] in their study of
rized as a syndrome associated with eating [1, 2]. WHO the physicochemical properties of geophagic clayey soils
[3] highlighted that this captures a wide range of exces- from South Africa and Swaziland. The presence of iron
sive and insistent consumption of both nutritional and oxide in clay and the water retention capacity of clay
non-nutritional objects without the intention of deriving was also found to alleviate anemia and diarrhea
nutritional benefits but rather some satisfaction or pleas- respectively.
ure. Accordingly, pica may include eating of dust, earth, Geophagia has taken another twist in Ghana where
soil or clay (geophagia), corn or laundry starch (amylo- there has been reports of craving for geophagical soils
phagia) likewise ice or freezer frost (pagophagia), and a which are commercially mined or excavated from known
host of other materials as elaborated by [2]. (and usually uncontaminated) sources at depth, rather
Geissler et al. [4] reiterated that geophagy or geopha- than from the surface. Likewise, a penchant to eat ter-
gia is utterly applicable to the eating of soil which is mite mounds owing to its peculiar aroma and other at-
most common. Its practiced daily amongst healthy tributes as pica by pregnant women.
school going children in Kenya: it is not stigmatized and Although clay or soil consumption in Ghana has gone
continues well into their period of adolescence. Geoph- on for a very long time, perusal of pertinent literature
agy is mostly practiced by adult pregnant women and reveals scanty publications on the levels of heavy metals
sometimes young women. By implication, geophagy is and the risks assessments likewise how it impacts on
probably much more prevalent in the tropics than previ- consumers and its health implication to affect policy for-
ously estimated. Archival records shown by [5] suggests mulation. Some studies done by previous researchers
that women of the Ewe tribe in Ghana, for instance, can such as Macheka et al., 2016 [18], Meel, 2012 [19], Men-
consume an average quantities of 30 g of clay per day. In sah et al., [2] and Nkansah et al., [20] have pointed to
Uganda, according to reports by Kilbride and Kilbride varied health problems associated with its consumption.
[6] as well as Ziegler [7] also suggest that women have a The objective of this study was therefore to assess the
penchant for the peculiar taste and flavor of clay ob- potential health risk associated with clay prepared for
tained from mounds of termite, ant hills or walls of the consumption as pica from Anfoega by pregnant women
hut, of which they will often cook over the fire for its in the Volta Region of Ghana as well as people from im-
improvement before consumed. An inadvertent and mediate neighboring countries Togo, Benin, Burkina
common form of geophagy occurs when individuals Faso etc. who may consume it.
enjoy inhaling dust arising from the soil prior to rainfall
or drizzle [5]. Methods
Clay consumption is a common practice especially Study area, location
among women and is often linked with pregnancy, fam- The Kaolin samples were purchased from Anfoega in
ine, idleness and insufficiency [8, 9]. In Ghana, it is esti- the Volta Region. Anfoega is positioned in North Dayi
mated that about 28% of women of reproductive age district of the Kpando Municipality of the Volta Region,
who practice geophagy, consume a daily average of 70 g Ghana. It has geographical coordinates of 6° 53′ 0“
of clay [10]. Apparently, eating of clay and or soil as a North, 0° 18’ 0” East and its original name (with dia-
habit was observed to be less frequent in boys than in critics) is Anfoega Akukome.
girls. Furthermore, soil eating in boys is reported to de-
crease with age [11]. Geophagia has been shown to be Sampling of kaolin
prevalent among females in the teenage bracket and that Anfoega in the Volta region of Ghana was where baked
by intensifying the education of these females, geophagia kaolin samples were obtained from. It’s a location where
and its consequences can be minimized significantly majority of the kaolin ore is mined and processed
[12]. (moulded and baked) for distribution and sale to mar-
Harmful heavy metals such as arsenic, lead, mercury kets in and around Ghana (especially Togo and Benin)
and cadmium have been confirmed to have a strong cor- for consumption. They were packaged in plastic con-
relation with human health according to some research tainers and kept in low freezing temperatures (ice chest)
works [9, 13]. In the same light, other researchers linked at 4 °C and transported under aseptic conditions to the
geophagy to potential bacterial, fungal and parasitic in- laboratory.
fections [14, 15] while there could also be a potential ex-
posure to radioisotopes [16] in the soil via geophagia. Sample preparation for mineral analysis
Notwithstanding, some beneficial microbiological health The clay ore specimens were ground with mortar and
effects associated with geophagia in humans include the pestle into powder and sieved using a 0.1 mm mesh.
Kortei et al. BMC Pregnancy and Childbirth          (2020) 20:160 Page 3 of 7
About 100ml of distilled water was added to 100 g of the heavy metals. To evaluate the risk of heavy metals
the weighed specimen. The specimen was then placed from clay consumption at the extreme, we made the fol-
on a shaker at 125 rpm for 12 h and then allowed to set- lowing assumptions in this research: the ingested dose
tle. The samples were filtered using a whatman 40 filter was equal to the absorbed pollutant dose [20]; cooking
paper. The supernatant was then used for the analysis. (baking) has no effect on the pollutants [26]; the average
adult body weight of Ghanaians was 60 kg [27]; Average
Determination of mineral elements in clay daily consumption of clay in Ghana is 70 g clay per day
The dry ashing method was used for atomic absorption [10]. Therefore, the EDI of heavy metals for adults was
spectrophotometer (AAS) analysis as described by calculated as follows:
AOAC [21]. One percent (1%) nitric acid was used to
wash all glass wares followed by demineralised water. C xC cons
Three millilitres (3 ml) each of the clay supernatants EDI ¼ ð1Þ
Bw
were weighed into platinum crucibles. The crucible and
the test portion were placed in a Muffle furnace at a
temperature of 550 °C for 8 h. The crucible with ash was where C is the concentration of heavy metals in clay
put in a desiccator to cool. Five millilitres (5 ml) of nitric sample (mg/kg wet weight), C cons is the average daily
acid of mass fraction not less than 65%, having a density consumption of clay in the local area (70 g/day Bw) [10],
of approximately ρ (HNO3) = 1400 mgml
− 1 was added, and Bw represents the female body weight (60 kg) [27].
ensuring that all the ash came in contact with the acid Table 1 shows the international guidelines and exposure
and the resultant solution heated on hot plate until the parameters used for the risk estimations.
ash was dissolved. Ten millilitres (10 ml) of 0.1 mol l− 1
nitric acid was added and filtered into 50ml volumetric Determination of target Hazard quotient (THQ)
flask. The resultant solution was topped up to the mark Target hazard quotients (THQ) were developed by the
with 0.1 mol l− 1 nitric acid. Blank solution was treated United States Environmental Protection Agency for the
the same way as the sample. Absorbance values at ap- estimation of potential health risks associated with long
propriate wavelengths of the interested metal in the term exposure to chemical pollutants. THQ is a ratio be-
sample solution were read using the Buck Scientific tween the measured concentration and the oral refer-
210VGP Flame AAS (Buck Scientific, Inc. East Norwalk, ence dose, weighed by the length and frequency of
USA). Cathode lamps used were copper (Cu) (wave- exposure, amount ingested and body weight. THQ value
length 324.8 nm, lamp current 1.5 mA), iron (Fe) (wave- is a dimensionless index of risk associated with long
length 248.3 nm, lamp current 7.0 mA), manganese (Mn) term exposure, amount ingested and body weight.
(wavelength 279.5 nm, lamp current 3.0 mA), lead (Pb) The THQ, the ratio of the exposure dose to the refer-
(wavelength 217.0 nm, lamp current 3.0 mA) and zinc ence dose (RfD), represents the risk of non-carcinogenic
(Zn) (wavelength 213.9 nm, lamp current 2.0 mA). Air/ effects. If it is less than 1, exposure level is less than the
acetylene gas was used for all the analyses. Calibration RfD. This indicates the daily exposure at this level is un-
curves made up of a minimum of three standards were likely to cause adverse effects during a person’s lifetime,
used to detect the metal contents of the samples. and vice versa.
The dose calculations were performed using standard
Human health risk assessment of heavy metals in clay assumptions from the integrated USEPA risk analysis
In the risk assessment involved with the consumption of
contaminated clay samples pose to humans, several Table 1 Exposure parameters used for the health risk
health risk estimation methods have been proposed and estimations via consumption of clay [27] (US EPA)
used by some researchers [22–24]. One method is the Parameter Unit Child Adult
Estimated Daily Intake (EDI), which helps to identify the Body Weight (BW) Kg 15 75
quantity of pollutant consumed daily [25]. The EDI of
Exposure Days/ years 365 365
potentially toxic elements (PTE) relies on the concentra-
tions of PTE in the clay and the daily clay consumption. Frequency (EF)
In addition, human body weight has an important influ- Exposure Years 6 30
ence on the tolerance to contaminants [25]. Duration
Ingestion Rate (IRclay) mg/day 200 100
Tolerable daily intake and estimated daily intake Average Time (AT) Days/years
The estimated daily intake (EDI) depends on the metal
For carcinogenic 365 × 70 366 × 70
concentration, food consumption, and body weight.
Table 3 shows the Permitted Daily Intake (PMTDI) of For non-carcinogenic 365x ED 365x ED
Kortei et al. BMC Pregnancy and Childbirth          (2020) 20:160 Page 4 of 7
[26]. The model for estimating THQ was determined by
the following equation [26]: Total THQ ðTTHQÞ ¼ THQ ðtoxicant 1Þ
þ THQ ðtoxicant 2Þ
¼ EFr x EDtot x FIR x C
þ THQ ðtoxicant nÞ ð4Þ
THQ x10−3 ð2Þ
RfDo x Bw x ATn
where EFr is the exposure frequency (350 days/year); Statistical analysis
EDtot is the exposure duration (30 years); FIR is the clay Results obtained was analyzed using IBM SPSS statistics
ingestion rate (g/day), and 10− 3 is the unit conversion version 22.0. Elemental minerals concentrations were
factor; C is the heavy metal concentration in clay (mg/kg obtained from duplicates and presented as mean con-
wet weight); RfDo is the oral RfD (mg/kg-day); Bw is the centration and standard deviations.
average adult body weight (60 kg); and ATn is the aver-
age exposure time for non-carcinogens (365 days/year × Results
number of exposure years, assuming 30 years). Results of the different concentrations of minerals both
micro and macro elements are presented in Tables 2
Non-carcinogenic effect and 3. Concentrations of the macro elements investi-
gated were 1.38 ± 1.5, 2.40 ± 1.5, 7.74 ± 1.5, 4.01 ± 1.0,
HQ ¼ EDI ð3Þ 13.24 ± 2.2 and 13.76 ± 2.1 mg/Kg for Fe, Cu, Zn, K, Mg
RfD and Na respectively. While that for the micro elements
were 1.63 ± 0.03 μg/Kg, 4.72 ± 0.8, 0.53 ± 0.02 and 1.85 ±
where HQ is the hazard quotient and RfD is the refer- 0.3 mg/kg respectively for As, Mn, Pb and Ni.
ence dose (mg kg− 1 day− 1). HQ values of < 1 signify un-
likely adverse health effects, while HQ values > 1 Reference doses for the various elemental minerals
indicate a likely adverse health effect. were of range 3.0 × 10− 4 – 0.14 mg kg− 1 day− 1 as used
in this study (Table 4) Estimated Daily Intakes of toxic
Carcinogenic risk assessment metals in clay samples of this study recorded range
Carcinogenic risk assessment estimates the probability values of 0.611–5.44 (mg/kg Bw/day).
of an individual developing cancer over a lifetime due to Hazard Quotient which is expressed as a quotient of
exposure to the potential carcinogen is presented in the Estimated Daily Intake (EDI) to the Reference Dose
Table 1. (RfD) were also of range 6.26 × 10− 4 – 106.5.
In this assessment, a caner slope factor was used to Values of the THQ and TTHQ (Total Target Hazard
convert the EDI of the heavy metals over a lifetime ex- Quotient) ranged 0.067–10.34 and 15 respectively.
posure to risk of an individual developing cancer [28]. Cancer risk analysis yielded a range of values of
X 0.052–19.38. Arsenic and Nickel potentially posed can-
Risk ¼ n; I ¼ 1 EDI x CSF cer risk to clay consumers (Table 5).
CSF ¼ Cancer Slope Factor Discussion
Exposures to chemicals during early life stages can result
in adverse effects during the stage when exposure oc-
Total target Hazard quotient curred or may not manifest themselves until later stages.
In this study, the total THQ was expressed as the arith- Depending on the dose of the chemical and the suscepti-
metic sum of the individual metal THQ values according bility during that life stage to the mode of action of the
to the method of [26]: chemical, effects can range in severity from functional
Table 2 Concentrations of essential macro and trace elements in clay samples
Mineral Element Concentration (mg/Kg) Recommended Dietary Intake (RDI), WHO [28]
(Mean ± SD)
Iron 1.38 ± 1.5 18 mg
Copper 2.40 ± 1.5 0.9 mg
Zinc 7.74 ± 1.5 11 mg
Potassium 4.01 ± 1.0 3100–3500 mg
Magnesium 13.24 ± 2.2 280–350mg
Sodium 13.76 ± 2.1 500–2400mg
Kortei et al. BMC Pregnancy and Childbirth          (2020) 20:160 Page 5 of 7
Table 3 Mean concentrations of toxic trace elements in clay Table 5 Calculated Estimated Daily Intake, Hazard Quotient,
sample Target Hazard Quotients and Cancer Risks of the Heavy metals
Mineral element Mean Concentration WHO/FAO PMTDI PMTDI for 60 in clay samples
(Mean ± SD) (μg/Kg BW/day) Heavy Metal Sample EDI HQ THQ Cancer
Arsenic 1.63 ± 0.03 μg/Kg 3.0 180 (mg/kg Bw/day) Risk
Manganese 4.72 ± 0.8 mg/Kg 4.9 mg/Kg 294 Arsenic Clay 1.88 6.26 × 10
−4 2.62 2.82
Lead 0.53 ± 0.02 mg/Kg 3.0 180 Copper Clay 2.767 0.069 0.067 N/A
Lead Clay 0.611 1.75 × 10− 3Nickel 1.85 ± 0.3 mg/Kg 5.0 300 1.69 0.052
Manganese Clay 5.44 38.86 0.377 N/A
Nickel Clay 2.13 106.5 10.34 19.38
deficits to growth restriction to malformations to ultim-
N/A Not available
ate mortality [31, 32]. Total Target Harzard Quotient (Clay) = 2.62 + 0.067 + 1.69 + 0.377 + 10.34=15
There has been an increased risks of a range of antag-
onistic neuro-cognitive developmental effects and in- multiple organs in the body are targeted by Lead due to
creased neonatal and postnatal mortality, spontaneous systemic toxicity as emphasized by Mahurpawar [33].
abortion, suggest: low weight at birth, increased number Manganese and Nickel levels were also below the set
of still births [32]. limits. In Tanzania, ranges of 2.3–128 and 2.9–1400mg/
Al-Rmalli et al. [9] suggested that an uncertain con- Kg for Nickel and Manganese respectively were reported
sumption of 50.0 g of soil taken from an arsenic contam- by Nyanza et al. [34]. Conversely, [30] did not detect any
inated area per day is equivalent to 0.370 mg of Arsenic Manganese in the clay samples from Ghana. Essentially,
ingestion. From our results, the levels of Arsenic ob- for bone formation and carbohydrate metabolism, Man-
tained was below the mean exposure level of 3.0 μg/Kg ganese is an essential nutrient involved.
BW/day set by the Joint FAO/WHO Expert Committee The estimated safe and adequate intake for copper is
on Food Additives [29]. Tayie et al. [10] reported 0.0 1.5–3.0 mg/day. Excessive ingestion of Copper could
(nil) mg/Kg of Arsenic in clay samples in Accra were lead to severe mucosal irritation and corrosion; capillary,
found to be lower than results obtained in this study. hepatic and renal damages; and gastrointestinal and
However, Nkansah et al. [27] reported a range of 218– neural disturbances [35]. Copper toxicity seldom occurs
271 ppm from clay samples obtained from different parts but may occur and its consequences may be severe. In-
of Kumasi Metropolis. Furthermore, Doe et al. [30] also takes of supplements exceeding 3 mg copper/day for a
reported Arsenic levels of range 2.7–22.74 μg/g in nine protracted period of time may be a cause for concern
(9) samples of clay samples collected from both Greater [36]. Results obtained in this study was observed to be
Accra and Kumasi of Ghana. Gastric symptoms such as far below and so contradicted that reported by Nyanza
stomach upset, nausea, vomiting, obstruction in the cir- et al. [34] of range 3.9–169mg/Kg for geophagic soils in
culatory as well as nervous systems and ultimately death Tanzania.
according to Mahurpawah [33], can be a consequence of
intakes of large quantities of Arsenic. Health risk assessment
Lead concentrations were observed to be below the Bonglaisin et al. [37] highlighted that the possibility and
mean exposure levels and was in contrast with findings the danger of lead or heavy metals getting into human
of range of values 549–622.92 μg/Kg reported by Nkan- food chain through eating contaminated clay (by birds,
sah et al. [27]. In line with our results, Tayie et al. [10] animals etc.,) should be dreaded. In children for ex-
reported 2.36 ± 0.08 mg/100 g. Lead consumption can re- ample, such an exposure would lead to adversarial health
sult in adverse health effects such as the dysfunction of consequences on the developing brain, which may result
some vital organs such as kidneys, liver and heart. Also, in long-term cerebral deficits as evidenced in records.
Results obtained in this research is in agreement with
published findings of [38] in a related study to investi-
Table 4 Reference doses (RFD) mg kg− 1 day− 1 for heavy metals gate the health risks posed to pregnant women and chil-
used in this study dren who practice geophagia in Nigeria and found in
Heavy metals Reference Doses Cancer slope factor References their study high Arsenic, Lead and Cadmium to be in
Arsenic 3.0 × 10−4 1.50 [27, 29] excess above tolerable limits which yielded hazard quo-
Copper 4.0 × 10− 2 N/A [29] tient and Target Harzard Quotient values of > 1 made
Lead 3.5 × 10− 3 8.5 × 10− 3 [27] clay consumption as pica unsafe and likely to cause ad-
verse effects.
Manganese 0.14 N/A [29]
Clay samples obtained from Kumasi, Ghana as worked
Nickel 0.02 9.10 × 10− 1 [29, 30] on by Nkansah et al. [27] recorded Hazard index values
Kortei et al. BMC Pregnancy and Childbirth          (2020) 20:160 Page 6 of 7
of range 0.064. Arsenic was identified as the most haz- obnoxious. Apparently, it is inevitable that geophagy
ardous element. A cancer risk assessment confirmed this practice will persist despite urbanization and civilization,
as a calculated value of 2.2 × 10− 5 was reached. Although we therefore support finding ways of reducing heavy
the hazard index (HI) was below the prescribed unity metal pollutants in geophagic clays through suitable re-
(1), their cumulative effect was of concern. It could be mediation technology that could minimize the effects of
estimated that the overall non-carcinogenic risk assess- toxic metals on the human system.
ment on the health of consumers within the Kumasi Collection of specimen (soils) used in our study com-
Metropolis pointed to more risk via the ingestion route plied with guidelines outlined by the Research and Ethics
(HI = 0.064). Committee of the University of Health and Allied Sci-
In another related study by Kamunda et al. [39] in ences, Ho, Ghana.
South Africa on toxic elements in soils of a Gold mining
basin, they reported HQ values of 2.13 suggestive of Abbreviations
non-carcinogenic effects noteworthy to the adult popula- EDI: Estimated Daily Intake; HQ: Hazard Quotient; THQ: Target Hazard
tion. Nonetheless, a much greater value of 43.80 was re- Quotient; TTHQ: Total Target Hazard Quotient; PMTDI: Permitted Maximum
Tolerable Daily Intake; WHO: World Health Organization; FAO: Food and
corded for children oral exposure which posed severe Agriculture Organization; USEPA: United States Environmental Protection
non-carcinogenic risk effects to children living in the Agency; RDI: Recommended Dietary Intake; SPSS: Statistical Package for
mining area. Again, their carcinogenic risks (1.7 × 10− 4) Social Sciences
have been found to be to be greater than acceptable
values. Acknowledgements
We acknowledge and sincerely extend our heartfelt appreciation to Mr.
From China, Liu et al. [40] reported a potential health Sowah and all the laboratory technicians of Department of Biochemistry
risk linked with Arsenic and Chromium exposure for laboratory, University of Ghana for carrying out the elemental mineral
residents while risk assessment results which suggested analysis.
that there were carcinogenic risks of Arsenic and Chro-
mium via corresponding exposure pathways which Authors’ contributions
exceeded the safety limit of 10− 6 (the acceptable level of NKK, AK-D, PTA and NYBM designed the study, NKK, EKE and NYBM carried
out the experiment, data collection and analysis and wrote the first version
carcinogenic risk for humans). Cancer causing risk of of the manuscript. NOB, AK-D, PTA, CT and MA-A contributed to interpret-
heavy metals is the summation effect of the individual ation of data and critically revised the manuscript. All authors read and ap-
metals contributing to the cancer risk. Results of this proved the final manuscript.
study indicated that the sum of cancer risks of the indi-
vidual metals for the examined toxic metals could pose Funding
This work received no funding other than salary support from respective
cancer risk effect to both children and adults through employers.
the consumption of examined clay samples contami-
nated with Lead, Arsenic and Nickel from the Anfoega
Availability of data and materials
clay mining site. The datasets used and/or analysed during the current study available from
the corresponding author on reasonable request.
Conclusions
Essential nutrients such as Potassium, Iron, Calcium and Ethics approval and consent to participate
Zinc; and toxic metals such as Arsenic, Lead and Mer- Research did not involve human subjects.
cury were detected in white clay soils mainly from
Anfoega, Volta Region and sold for consumption in al- Consent for publication
most all markets within the region and beyond. The Not applicable.
presence of these metals in the clay could be largely due
to natural occurrence and a less likely influence of hu- Competing interests
The authors declare that they have no competing interests.
man activities such as handling and or the baking
process. The estimated levels of heavy metals contained Author details
1
in 70 g of the geophagic clay consumed by inhabitants in Department of Nutrition and Dietetics, School of Allied Health Sciences,
University of Health and Allied Sciences, PMB 31, Ho, Ghana. 2Department of
the Ho municipality and beyond were found to be high Food Processing and Engineering, CSIR- Food Research Institute, P.O. Box
compared to the Permitted Maximum Tolerable Daily M20, Accra, Ghana. 3Department of Nutrition and Food Science, School of
Intake (PMTDI) prescribed by (WHO/FAO). There is a Biological Sciences, College of Basic and Applied Sciences, University of
Ghana, P.O. Box LG 25, Accra, Ghana. 4Department of Medical Laboratory
possibility of bioaccumulation after the consumption of Sciences, School of Allied Health Sciences, University of Health and Allied
these clays by adult pregnant women especially over a Sciences, PMB 31, Ho, Ghana. 5Animal Health and Food Safety Division, CSIR-
long period of time which poses a potential health men- Animal Research Institute, P.O. Box AH20, Achimota, Ghana.
6Department of
Chemistry, Kwame Nkrumah University of Science and Technology, Kumasi,
ace. Human consumption of these clay materials which Ghana. 7Department of Biomedical Sciences, School of Basic and Biomedical
contain high levels of toxic metals render them Sciences, University of Health and Allied Sciences, PMB 31, Ho, Ghana.
Kortei et al. BMC Pregnancy and Childbirth          (2020) 20:160 Page 7 of 7
Received: 22 October 2019 Accepted: 5 March 2020 25. Vrhovnik P, Arrebola JP, Serafimovski T, Dolenec T, Šmuc NR, Dolenec M,
Mutch E. Potentially toxic contamination of sediments, water and two
animal species in Lake Kalimanci, FYR Macedonia: relevance to human
health. Environ Pollut. 2013;180:92–100.
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