Biological Evidence 2018, Vol.8, No.2, 6-20
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vegetables. Most of the seasonings contain plant materials as a major ingredient. Most common food seasonings
and culinary condiments are used for cooking of meats (animal flesh), rice of various kinds (jollof, stew) and
soups. Rice is one of the major sources of staple food in the world. While most families in developing country like
Nigeria obtain their animal protein from chicken, beef and goat meats in addition to fish especially in urban areas.
Since most of the seasonings contain plants materials from pepper, carrot, nutmeg, onions, garlic, black pepper,
parsley, mustard, sesame etc. as major ingredients, they contain several minerals such as calcium, potassium,
magnesium and sodium (cations), trace metals (iron, copper, chromium, zinc, manganese etc which are essential
metals and lead, arsenic, mercury and cadmium which are also non essential metals). Different parts of the plants
including leaves, fruit, flower, root, stem-back etc. are used for seasonings preparation depending on the producer
and type of plant.
Typically, plants have the tendency to bioaccumulate toxicant such as heavy metals from their environment,
thereby causing toxicity to the biota on exposure above recommended concentration (Aigberua et al., 2017). Izah
and Srivastav (2015) reported that humans are exposed to heavy metals through ingestion from food and drinking
water, dermal contact, inhalation and parenteral route. Among the various routes, Ihedioha et al. (2014), Seiyaboh
et al. (2018), Kigigha et al. (2018) opined that food is the most common non-occupational heavy metals exposure.
Some heavy metals play vital roles in human health. The roles of these heavy metals (essential ones) and their
roles, pathology and deficiency have been widely reported by authors (Palacios, 2006; Nnorom et al., 2007;
Muhammad et al., 2011; 2014; Iwegbue et al., 2013a; 2015a; Ihedioha et al., 2014; Prashanth et al., 2015;
Asomugha et al., 2016; Izah et al., 2016b; 2017a,b; Izah and Aigberu, 2017). Several studies have been conducted
with regard to trace metals in food substances and their associated health effects in Nigeria. Some of the food
resources mostly focused on includes livers and kidneys of cattle (Iwegbue, 2008; Seiyaboh et al., 2018), spices
(Iwegbue et al., 2011; Gaya and Ikechukwu 2016; Asomugha et al., 2016; Izah and Aigberua, 2017), chocolates
and candies (Iwegbue, 2011a; Ochu et al., 2012), honey (Iwegbue et al., 2015b), canned fish (Iwebue, 2015),
biscuits (Iwegbue, 2012), canned sardines (Iwegbue et al., 2009), milk (Iwegbue et al., 2013b), canned tomato
paste (Iwegbue et al., 2012), wines (Iwegbue, 2014), canned beef (Iwegbue, 2011b), chicken meat and gizzard and
turkey (Iwegbue et al., 2008a), canned fruit drinks (Iwegbue et al., 2008b), snail (Iwegbue et al., 2008c), gari
(Kigigha et al., 2018). But to the best of our knowledge information on health effects of packaged seasonings and
culinary condiment used in Nigeria is scanty in literature. Hence, this study aimed at [i] assessing the level of
trace metals in selected brands of seasonings and culinary condiment used in Nigeria, [ii] determining the dietary
intake and target hazard quotients from the consumption of the seasonings.
1 Materials and Methods
1.1 Sample collection
A total of 13 brands of edible food seasonings and culinary condiments were purchased from retail outlets within
Oil mill market, Port Harcourt, Rivers State, Nigeria. 3-4 samples of the same brands with different production
date were purchased. Details such as ingredients/compositions, country of production and packaging of the 13
brands of seasonings is presented in Table 1.
1.2 Reagents
Hydrochloric acid (HCl) 37 % (v/v) (Sigma-Aldrich, Steinheim, Germany), Nitric acid (HNO
3
) 69 % (v/v) Analar
(BDH, Poole, United Kingdom), working standards of Mn, Zn, Cd, Cu, Pb, Ni, Co and Cr were prepared by
diluting concentrated stock solutions of 1,000 mg/L (AccuNoHaz, New Haven, CT, USA) with 10% HNO
3.
1.3 Sample preparation
The seasonings and culinary condiments were cut open from their polyethylene sachets. The ones in powdery and
tiny leafy forms were grounded to powder. Then the seasonings samples were transferred into petri dishes with a
stainless steel spoon spatula before being oven-dried in a Memmert U27 type drying oven at 70°C for 24 hours
(Aigberua and Tarawou, 2017). Then after, 5 g dry weight of each sample was transferred into silica crucibles and
dry-ashed in an Oceanic SX-2 type muffle furnace at a temperature of 450°C until the samples were greyish-ash.
