Geochemical, ecological, and health risk assessment of potentially toxic elements (PTEs) in the surrounding soil of a cement plant

doi:10.21203/rs.3.rs-3585362/v1

Cement plants are the major anthropogenic sources of potentially toxic elements (PTEs), which are generated from the processing of raw materials and combustion of fossil fuels. This study determined the PTE concentration and assessed the geochemical, ecological, and health risks associated with the activities in the Ashaka cement plant, Bajoga, Nigeria. Soil samples were collected between 2019 and 2020, and analyzed by ICP-OES for 20 PTEs. The data obtained were statistically evaluated for descriptive and inferential statistics. The mean concentrations of PTEs were in the declined order of Al > Fe > Mn > Zn > Ti > Ba > Sr > Pb > Cu > V > Cr > Ni > As > Sc > Mo > Hg > Cd > Se > Sb > Co. Multivariate analysis revealed that the main sources of PTEs might be related to anthropogenic activities from cement plant. The geochemical load index (GLI) values obtained range from unpolluted to moderate. The ecological risk ranged from 4.74 × 10^− 3 to 8.00 × 10⁰, and the overall risk index indicated low contamination for the investigated elements. The hazard index (HI) was < 1, suggesting non-probable non-carcinogenic effects. However, children were more susceptible to risk than adults, and the cancer risk (CR) values of Cd for children and adults were higher than the threshold level of 1.0 × 10^− 4, which suggests probable development of cancer risk for residents.

Cement plant

Geochemical

Ecological risk

Health risk

Potential toxic elements

Environmental pollution with potentially toxic elements (PTEs) has since received global attention due to rapid urbanization and industrialization worldwide [1]. PTE contamination of the environment obstructs human health and natural ecosystem functions [2]. The significant concern of PTEs is their wide sources, non-biodegradability, bioaccumulation, and toxicity [3]. The incidence of PTEs in the environment could be from natural or anthropogenic (man-made) sources such as mining, fossil fuel combustion, and cement production [1]. It has been reported that cement plants are the major anthropogenic sources of PTEs, especially Hg, Pb, Ni, As, Cd, and Zn, because of raw materials processing and fossil fuel combustion [4, 5]. The deposition of PTEs occurs at different distances around the cement plant in ambient air and is then deposited on the ground as dry or wet precipitation, which leads to deterioration of soil quality [6].

Soil is a substance obtained from the Earth’s surface and is considered the ultimate sink of anthropogenic PTEs released into the environment through various sources [7]. Soils are generally considered as carriers of most PTEs released during anthropogenic activities [8]. Contamination of soil with PTEs is a worldwide environmental concern and continues to increase due to massive increases in industrialization, urbanization, human population, and consumption patterns [9, 10]. Soil deterioration by PTE can cause lasting problems in the biogeochemical cycle and may influence soil natural function, leading to changes in soil fauna [11], agricultural soils, and food crops [12].

Studies have revealed that PTEs are potentially toxic to plants and animals when water and soils polluted with them are used for crop growth [13, 14]. Consumption crops grown in contaminated soil reach humans through the food chain, and these PTEs are likely to bioaccumulate, resulting in health disorders in the human system [15]. Exposure to PTEs is associated with health implications to the human system, such as liver failure, nervous disorders, kidney disease, and neurotoxicity, either by ingestion or inhalation [16, 17]. Furthermore, there is a need for effective monitoring of PTE sources, and distribution to reduce environmental damages, checkmate pollution, and public health as a result of anthropogenic activities [12].

Moreover, studies of PTE concentrations and risk assessment on soils have been reported in Nigeria [12, 18–21]. However, limited or no study have been reported on geochemical, and risk assessments of the PTE study area. Hence, this studies determined PTE concentration, and assessed geochemical, ecological, non-carcinogenic, and carcinogenic risks related to the activities in the Ashaka cement plant, Bajoga, Nigeria, with the view of providing information on the impact of the cement plant activities on geochemical, ecological, non-carcinogenic, and carcinogenic risks.

2.1 Study area

The study area is Ashaka cement plant located in Ashaka town, 9 km north of Bajoga, Gombe State, Nigeria. The map of the area is shown in Fig. 1, located between longitudes 11^o 28' 30”E and 11^o 29^’ 30”E and latitudes 10^o55'30”N and 11^o56’30”N, and The climate is tropical with two distinct seasons (dry and wet). In the dry season between November-February is harmattan, and the hot period between March-April is of the dry season with temperature ranging from 31.1 to 42.1 ^oC. The maximum rainfall ranges from 800 mmto 900 mm (August-September) and a minimum of 250 mm to 350 mm (May-June), with relative humidity ranging from 60–80% [22].

2.2 Sample collection and preparation

A systematic sampling technique was used for sample collection with little modification [23]. The surrounding soil of a cement plant was collected at depths ranging from 0–15 cm (topsoil). Four subsamples within each sampling point were mixed to form a composite sample. A total of ninety three soil samples were collected. Approximately 50 g of soil samples were transferred into polyethylene bags, and subsequently transported to the laboratory and air-dried at room temperature for two weeks [24]. Before the determination of PTEs, substantial impurities were detached from the air-dried soil samples, pulverized using a mortar and pestle, and sieved viaa U.S. No. 10 (2 mm) mesh. Approximately 0.5 g of the soil was transferred into a Teflon cup, and a binary combination of 3.75 mL of HCl and 1.25 mL of HNO₃ was added as previously reported [25]. The resulting solutions were then analyzed for PTE concentration using inductively coupled plasma optical emission spectrometry (ICP-OES, Agilent 720-ES).

2.3 Quality assurance

The precision of the analytical procedure was determined by a recovery study. The recovery study was conducted by determining the PTE concentration in triplicate in spiked and un-spiked samples. The ICP-OES (Agilent 720-ES) was first calibrated using a multi-element standard solution (QCSTD-27). The percentage of mean recovery of the PTEs ranged from 98–104%, and the limits of detection for Al, As, Ba, Cd, Co, Cr, Cu, Fe, Hg Mn, Mo, Ni, Pb, Sb, Sc, Se, Sr, Ti, V and Zn were 0.013, 0.003, 0.004, 0.0001, 0.001, 0.0004, 0.0008, 0.01, 0.005, 0.0006, 0.0001, 0.005, 0.001, 0.0001, 0.0001, 0.003, 0.003, 0.003, 0.009 and 0.0003 µg/L, respectively.

2.4 Data analysis

The data obtained were statistically evaluated (simple descriptive and inferential) using SPSS software version 25. The generated data were used to estimate the potential ecological and health risks.

2.5 Geochemical load index (GLI)

The geochemical load index (GLI) was used to evaluate soil pollution by potentially toxic elements, as reported by other relative studies [12, 26, 27].

GLI = Log₂ [$\frac{{\text{C}}_{\text{i}}}{\text{G}\text{B}\text{V} \times 1.5 }$] (1)

Where C_i₌ measured elements (mg.kg^− 1), GBV₌ geóchemical backgróund vąlue of element, 1.5 ₌ control vąlues attributed to lithogenic variątion in the soil. The evaluation parameters of the geochemical analysis are presented in Table S1 (in the supplementary information).

2.6 Ecological risk assessment

Ecological risk was used to evaluate the overall soil pollution the expression proposed by Hakanson, [28].

C_f =$\frac{{\text{C}}_{\text{i}}}{{\text{C}}_{\text{o}}}$ (2)

$${\text{E}}_{\text{r}}^{\text{i}} = {\text{T}}_{\text{r}}\frac{{\text{C}}_{\text{i}}}{{\text{C}}_{\text{o}}}$$

3

R_i = $\sum {\text{E}}_{\text{r}}^{\text{i}}$ (4)

Where Ci ₌ measured elements, C_o ₌background value of elements, T_r ₌ toxic response factor,${\text{E}}_{\text{r}}^{\text{i}}$₌ potential ecological risk factor, and R_i₌ summation of ${\text{E}}_{\text{r}}^{\text{i}}$. The T_r and C_o values are shown in Table S2.

2.7 Health risk assessment

The PTEs measured in soil samples were used to evaluate health risk using the United States Environmental Protection Agency (USEPA) model and other previous studies [12, 24, 29]. Exposure through the three pathways was used.

ADD_inh=$\frac{\text{C} \times \text{I}\text{n}\text{h}\text{R} \times \text{E}\text{F} \times \text{E}\text{D} }{\text{P}\text{E}\text{P} \times \text{B}\text{W}\times \text{A}\text{T}}$ (5)

ADD_ing =$\frac{\text{C} \times \text{I}\text{n}\text{g}\text{R} \times \text{E}\text{F} \times \text{E}\text{D} \times \text{C}\text{F}}{\text{B}\text{W} \times \text{A}\text{T}}$ (6)

ADD_derm = $\frac{\text{C} \times \text{S}\text{L} \times \text{S}\text{A} \times \text{A}\text{B}\text{S} \times \text{E}\text{F} \times \text{E}\text{D} \times \text{C}\text{F}}{\text{B}\text{W} \times \text{A}\text{T}}$ (7)

The non-carcinogenic effect of PTEs using the hazard quotient (HQ) in soil samples using the expression below USEPA, [30].

HQ = $\frac{\text{A}\text{D}\text{D}}{\text{R}\text{f}\text{D}}$ (8)

The hazard index (HI) represents the summation of HQ multiple routes [31]. When HQ or HI > 1, the greater is the probability of non-carcinogenic adverse health effects to occur [30].

HI =$\sum _{\text{n}}^{\text{i}}{\text{H}\text{Q}}_{\text{i}}$ (9)

Cancer risk (CR) was evaluated using the expression below [30].

CR = ADD × CSF (10)

Where ADD ₌ average daily exposure dose of PTEs, RfD ₌ reference dose and CSF₌ cancer slope factor. The evaluation parameters for the exposure assessment are listed in Table S3.

3.1 Concentrations of PTE occurrence in soils

Table 1 presents the mean concentrations of PTEs in the soil surrounding the cement plant. The obtained data for each sampling point are presented in Table S4. The mean PTE concentrations were 398.44 ± 10.26, 0.15 ± 0.15, 1.89 ± 1.76, 0.07 ± 0.27, 0.001 ± 0.001, 0.39 ± 0.33, 0.64 ± 0.83, 219.73 ± 10.54, 0.08 ± 0.14, 6.23 ± 6.80, 0.11 ± 0.33, 0.26 ± 0.25, 0.68 ± 0.70, 0.01 ± 0.01, 0.12 ± 0.15, 0.03 ± 0.07, 1.63 ± 1.31, 1.97 ± 1.59, 0.44 ± 0.46 and 4.50 ± 4.18 mg·kg^− 1, for Al, As, Ba, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Sb, Sc, Se, Sr, Ti, V, and Zn, respectively. The PTE mean concentrations were in decline order of Al > Fe > Mn > Zn > Ti > Ba > Sr > Pb > Cu > V > Cr > Ni > As > Sc > Mo > Hg > Cd > Se > Sb > Co.

Table 1

Descriptive statistics of potentially toxic elements (mg·kg^− 1) in soil samples
Elements	Mean	SD	Median	Min	Max	Range	Skewness	Kurtosis
Al	398.44	10.26	391.28	223.99	612.77	388.78	0.50	0.59
As	0.15	0.15	0.14	0.00	0.66	0.66	2.08	6.52
Ba	1.89	1.76	1.28	0.28	7.80	7.51	2.08	6.02
Cd	0.07	0.27	0.00	0.00	1.21	1.21	4.22	18.21
Co	0.00	0.00	0.00	0.00	0.00	0.00	2.41	5.34
Cr	0.39	0.33	0.35	0.02	1.22	1.19	1.41	2.08
Cu	0.64	0.83	0.33	0.12	3.25	3.13	2.49	5.68
Fe	219.73	10.54	207.70	112.16	550.68	438.52	2.12	5.56
Hg	0.08	0.14	0.05	0.02	0.69	0.67	4.32	19.02
Mn	6.23	6.80	3.25	1.90	25.20	23.30	2.20	3.96
Mo	0.11	0.33	0.01	0.00	1.49	1.49	4.16	17.81
Ni	0.26	0.25	0.17	0.01	1.10	1.09	2.22	6.52
Pb	0.68	0.70	0.39	0.01	2.45	2.44	1.43	1.15
Sb	0.01	0.01	0.00	0.00	0.03	0.03	1.09	−0.61
Sc	0.12	0.15	0.05	0.02	0.58	0.55	1.86	3.13
Se	0.03	0.07	0.00	0.00	0.21	0.21	2.23	3.58
Sr	1.63	1.31	1.04	0.37	4.31	3.95	1.14	−0.22
Ti	1.97	1.59	1.85	0.24	6.64	6.40	1.47	2.82
V	0.44	0.46	0.23	0.00	1.76	1.76	1.42	2.10
Zn	4.50	4.18	2.90	0.54	15.60	15.06	1.37	1.27
Descriptive statistics were carried out by SPSS software

The most abundant measured PTEs were Al and Fe, whereas the other PTEs showed a minor distribution. From the observed skewness data, the biggest asymmetry was for Hg and Cd, followed by Cu, Co, Se, Ni, Mn, As and Ba. However, compared with the background values of the world average for soil, the mean concentrations of the investigated PTEs were lower than the world average elemental values [32]. The PTE concentrations observed in this study are lower than those reported outside Nigeria [29, 33–35] and in Nigeria [19–21, 36], but in comparable with those at Karst, Brazil [37], Odajana, Nigeria [28], and Canakale-Ezine, Turkey [39] presented in (Table 2), which indicate that cement production activities had less influence in the study areas. Moreover, it has been reported that an estimation of adverse health effects associated with PTEs, based on concentrations is not sufficient and must be followed with other estimated indices [16].

Table 2

Comparison of mean concentrations (mg·kg^-1) of potentially toxic elements in the soil samples and other studies
Site	Al	As	Ba	Cd	Co	Cr	Cu	Fe	Hg	Mn	Mo	Ni	Pb	Sb	Sc	Se	Sr	Ti	V	Zn	References
Ashaka, Bajoga	398.44	0.15	1.89	0.07	0.001	0.39	0.64	219.73	0.08	6.23	0.11	0.26	0.68	0.01	0.12	0.03	1.63	1.97	0.44	4.50	Present study
Ibese, Nigeria	−	−	−	0.76	−	11.91	−	−	−	−	−	1.82	1.41	−	−	−	−	−	−	2.06	Olatunde et al. (2020)
Konongo, Ghana	−	−	−	1.04	−	4.78	8.95	−	−	−	−	−	18.4	−	−	−	−	−	−	9.30	Awuah et al. (2022)
Douroud, Iran	0.247	−	−	−	−	115.77	80.47	−	−	−	−	139.07	56.27	−	−	−	−	−	−	135.73	Jafari et al. (2021)
Sokoto, Ngeria	−	−	−	0.04	−	−	0.55	−	−	−	−	−	0.38	−	−	−	−	−	−	3.55	Yahaya et al. (2021)
Karst, Brazil	−	−	−	0.06	5.22	35.53	10.87	−	−	490.76	−	4.77	21.04	−	−	−	−	−	−	27.02	Silva et al. (2021)
Canakale−ezine, Turkey	−	−	−	−	1.18	50.92	31.21	16007.	−	499.68	−	41.17	−	−	−	−	−	−	−	50.91	Parlak et al. (2023)
Obajana, Nigeria	−	−	−	0.96	ND	6.43	13.43		−	−	−	ND	−	−	−	−	−	−	−	−	Omolara et al. (2023)
Rabigh, Saudi Arabia	−	−	−	−	−	0.199	0.033	−	−	−	−	0.041	0.470	−	−	−	−	−	−	0.054	El−Sherbiny et al. (2019)
Ewekoro, Nigeria	−	−	−	−	−	62.52	9.18	16348.	−	341.13	−	−	50.00	−	−	−	−	−	−	82.76	Agbede et al. (2022)

3.2 Multivariate analysis

3.2.1 Correlation analysis

The results of CA for PTEs of the soil samples (p < 0.01 and p < 0.05) are presented in Table 2. The correlation shows that pair elements have a positive correlations (r > 0.5) with Cu-Al, Fe-As, Mn-Al, Mn-Ba, Ni-Al, Ni-Cd, Ni-Cr, Ni-Cu, Se-Mo, Sr-Al, Sr-Ba, Sr-Mn, Sr-Ni, Ti-Ba, V-Al, V-Ba, V-Mn, V-Sr, Zn-Cd, Zn-Cu, and Zn-Ni at p < 0.01 and Cd-Al, Cr-Cd, Cu-Al, Cu-Cr at p < 0.05. The strong correlation showed that some PTE pairs at (p < 0.01 and p < 0.05) signify their concurrent discharge from a similar source. The Sc shows non-interaction with other PTEs, this indicated Sc perhaps not originated from cement plant activities.

3.2.2 Principal Components Analysis

PCA was conducted to identify the source of PTE at the sampling points [12]. Table 3 presents the results of the PCA and four components demonstrating 64% cumulative total variance (TV) of the diverse PTEs in the samples. Al, Ba, Mn, Sr, Ti, and V with a TV of 20% correlated with the first component. This might be due to anthropogenic sources. Cd, Co, Cr, Cu, Ni, and Zn with a TV of 19% correlated with the second component. The combination of Cd, Ni, and Cu are known to be from crude oil sources and transportation [40]. This could be due to emissions of automobile exhaust and machines used. The third component correlated with As, Sn, and Mo with a TV of 13%, and As, Fe, Hg, Mo, Sb, and Se with a total variance of 13% (Fig. 2), which indicated that the third and fourth components were contributed through paedogenic and lithogenic origin. These observations concur with the correlation result that predicted Sc may not be from cement plant activities.

Table 3

Correlation analysis for the potentially toxic elements in the soil samples
Elements	Al	As	Ba	Cd	Co	Cr	Cu	Fe	Hg	Mn	Mo	Ni	Pb	Sb	Sc	Se	Sr	Ti	V	Zn
Al	1
As	0.247	1
Ba	0.377	−0.209	1
Cd	.520*	0.06	0.078	1
Co	−0.018	0.042	0.142	−0.112	1
Cr	0.339	0.205	0.281	.557*	0.425	1
Cu	.547*	0.09	0.065	.736**	−0.106	.546*	1
Fe	0.373	.741**	−0.276	0.409	−0.125	0.183	0.285	1
Hg	0.036	0.029	−0.146	−0.02	0.088	−0.072	−0.08	0.178	1
Mn	.652**	0.028	.690**	0.28	−0.196	−0.005	0.303	0.111	−0.064	1
Mo	0.234	−0.224	0.084	0.149	−0.117	0.251	0.163	0.081	−0.079	−0.035	1
Ni	.652**	0.212	0.317	.804**	0.059	.754**	.692**	0.396	−0.028	0.358	0.373	1
Pb	0.271	−0.005	0.293	0.183	0.005	0.373	0.176	−0.13	−0.154	−0.06	0.004	0.386	1
Sb	0.026	−0.121	−0.011	−0.121	0.356	0.359	−0.189	−0.098	−0.158	−0.296	0.406	0.132	0.173	1
Sc	−0.214	−.486*	0.005	−0.108	0.392	−0.122	−0.219	−0.304	−0.242	−0.194	0.131	−0.136	−0.062	0.206	1
Se	0.042	0.039	0.104	−0.111	0.391	0.433	−0.06	0.015	0.207	−0.244	.562**	0.325	0.184	.627**	−0.094	1
Sr	.582**	0.252	.584**	0.317	−0.221	0.19	0.277	0.43	−0.003	.758**	0.302	.570**	−0.031	−0.141	−0.152	0.081	1
Ti	0.172	−0.417	.846**	0.27	0.156	0.335	0.105	−0.351	−0.037	0.425	0.148	0.343	0.264	−0.126	0.207	0.038	0.423	1
V	.728**	0.11	.604**	0.288	−0.085	−0.009	0.272	0.148	−0.112	.895**	−0.136	0.359	0.173	−0.316	−0.06	−0.335	.609**	0.344	1
Zn	0.113	0.142	−0.021	.624**	−0.23	.497*	.563**	0.087	−0.124	−0.104	0.137	.592**	0.43	−0.106	−0.283	0.054	0.056	0.204	−0.109	1
*. Correlation is significant at the 0.05 level (2−tailed).
**. Correlation is significant at the 0.01 level (2−tailed).

3.2.3. Cluster analysis

Cluster analysis grouped PTEs that were likely from similar sources [41]. The PTEs are grouped into two clusters in Fig. 3, where Mn, V, Al, Sr, Ba, and Ti are in one group, while Cd, Ni, Cr, Zn, Pb, Sb, Se, Mo, Co, Sc, and Hg are in the second group. The cluster analysis showed that Mn, V, Al, Sr, Ba, and Ti, which have a related source, and are not inclined by Cd, Ni, Cr, Zn, Pb, Sb, Se, Mo, Co, Sc and Hg, but the presence of Zn, Cd, Cr, Pb, Ni is influenced by Sb, Se, Mo, Co, Sc, and Hg, signifying that they are from a similar source. These observations concur with the PCA result, which showed that Al, Ba, Mn, Sr, Ti, and V may be from the same sources. Thus, the PTEs in groups one and two of the cluster are probably from anthropogenic or paedogenic sources [24].

3.3 Geochemical load index

Table 4 presents the geochemical load index (GLI) of the soil samples. The results of GLI show that the samples ranged from unpolluted to moderate for the investigated PTEs. The GLI values of the PTEs were in the following trend of Cd > Hg > Sb > Se > Al > Zn > Mo > Pb > Cu > As > Sc > Mn > Sr > Cr > Ni > V > Ba > Ti > Co. The GLI result in this study was consistent with values reported in previous studies [29, 42], but lower than values reported by [33, 35, 37, 28].

Table 4

Principal component analysis of potentially toxic elements in the soil samples
Elements	Component
Elements	1	2	3	4
Al	.388	.708	.278	.100
As	.044	.095	.911	−.054
Ba	−.032	.784	−.425	.114
Cd	.932	.198	.005	.058
Co	.952	−.062	−.039	.161
Cr	.651	.078	.075	.355
Cu	.843	.167	.096	−.117
Fe	.338	.164	.790	.037
Hg	−.023	−.059	.073	.885
Mn	.074	.939	−.025	−.183
Mo	.298	.083	−.182	.796
Ni	.810	.396	.130	.285
Pb	.232	.063	.755	.101
Sb	−.078	−.170	.015	.778
Sc	−.047	−.105	−.499	.044
Se	.032	−.034	.046	.896
Sr	.220	.834	.127	.193
Ti	.218	.505	−.686	.025
V	.084	.889	.059	−.301
Zn	.747	−.184	−.020	−.014
Eigen values	4.096	3.749	2.533	2.501
% of Variance	20.478	18.746	12.667	12.504
Cumulative %	20.478	39.224	51.891	64.395
Strong correlation is shown in bold font

Table 4

Geochemical load index and potentially ecological risk indices of the soil samples
Elements	Geochemical load index			Ecological risk
Elements	GLI	Pollution level		${\text{E}}_{r}^{i}$	Class
Al	9.99 × 10⁻⁰³	unpolluted to moderate		−	−
As	2.32 × 10⁻⁰³	unpolluted to moderate		1.15 × 10⁻⁰¹	Low
Ba	6.54 × 10⁻⁰⁴	unpolluted to moderate		6.52 × 10⁻⁰³	Low
Cd	4.68 × 10⁻⁰²	unpolluted to moderate		6.99 × 10⁰⁰	Low
Co	1.06 × 10⁻⁰⁵	unpolluted to moderate		2.66 × 10⁻⁰⁴	Low
Cr	8.70 × 10⁻⁰⁴	unpolluted to moderate		8.66 × 10⁻⁰³	Low
Cu	2.85 × 10⁻⁰³	unpolluted to moderate		7.11 × 10⁻⁰²	Low
Fe	9.34 × 10⁻⁰⁴	unpolluted to moderate		−	−
Hg	4.01 × 10⁻⁰²	unpolluted to moderate		8.00 × 10⁰⁰	Low
Mn	1.47 × 10⁻⁰³	unpolluted to moderate		7.33 × 10⁻⁰³	Low
Mo	8.49 × 10⁻⁰³	unpolluted to moderate		6.35 × 10⁻⁰¹	Low
Ni	7.67 × 10⁻⁰⁴	unpolluted to moderate		1.91 × 10⁻⁰²	Low
Pb	6.82 × 10⁻⁰³	unpolluted to moderate		1.70 × 10⁻⁰¹	Low
Sb	1.34 × 10⁻⁰²	unpolluted to moderate		6.67 × 10⁻⁰²	Low
Sc	1.85 × 10⁻⁰³	unpolluted to moderate		−	−
Se	1.00 × 10⁻⁰²	unpolluted to moderate		−	−
Sr	1.09 × 10⁻⁰³	unpolluted to moderate		−	−
Ti	8.59 × 10⁻⁰⁵	unpolluted to moderate		4.28 × 10⁻⁰⁴	Low
V	6.79 × 10⁻⁰⁴	unpolluted to moderate		1.93 × 10⁻⁰²	Low
Zn	9.51 × 10⁻⁰³	unpolluted to moderate		4.74 × 10⁻⁰³	Low
			RI	16.15	Low

Table 5

Non-carcinogenic hazard quotient (HQ) and hazard index (HI) of potentially toxic elements in soil samples
Elements	Age group	Exposure pathways
Elements	Age group	Ingestion (HQ)	Inhalation (HQ)	Dermal (HQ)
Al	Children	5.31 × 10⁻⁰²	1.95 × 10⁻⁰⁷	−
Al	Adults	6.64 × 10⁻⁰³	9.77 × 10⁻⁰⁸	−
As	Children	6.67 × 10⁻⁰²	2.45 × 10⁻⁰⁷	5.37 × 10⁻⁰⁴
As	Adults	8.33 × 10⁻⁰⁸	1.22 × 10⁻⁰⁷	1.14 × 10⁻⁰⁴
Ba	Children	3.60 × 10⁻⁰³	6.48 × 10⁻⁰⁶	2.00 × 10⁻⁰⁴
Ba	Adults	4.50 × 10⁻⁰⁴	3.24 × 10⁻⁰⁶	3.59 × 10⁻⁰⁵
Cd	Children	9.33 × 10⁻⁰²	3.43 × 10⁻⁰⁷	3.08 × 10⁻⁰³
Cd	Adults	1.17 × 10⁻⁰²	1.72 × 10⁻⁰⁷	6.53 × 10⁻⁰⁴
Co	Children	6.65 × 10⁻⁰⁶	8.58 × 10⁻⁰⁸	2.75 × 10⁻⁰⁸
Co	Adults	8.35 × 10⁻⁰⁷	4.29 × 10⁻⁰⁸	5.83 × 10⁻⁰⁹
Cr	Children	1.73 × 10⁻⁰²	6.68 × 10⁻⁰⁶	2.87 × 10⁻⁰³
Cr	Adults	2.17 × 10⁻⁰³	3.34 × 10⁻⁰⁶	6.08 × 10⁻⁰⁴
Cu	Children	2.13 × 10⁻⁰³	7.81 × 10⁻⁰⁹	2.76 × 10⁻⁰⁵
Cu	Adults	2.68 × 10⁻⁰⁴	3.91 × 10⁻⁰⁹	5.86 × 10⁻⁰⁶
Fe	Children	4.19 × 10⁻⁰²	−	1.30 × 10⁻⁰⁴
Fe	Adults	5.24 × 10⁻⁰⁵	−	2.93 × 10⁻⁰⁵
Hg	Children	3.57 × 10⁻⁰³	1.31 × 10⁻⁰⁷	1.68 × 10⁻⁰³
Hg	Adults	4.43 × 10⁻⁰³	6.53 × 10⁻⁰⁸	3.60 × 10⁻⁰⁴
Mn	Children	1.81 × 10⁻⁰²	2.18 × 10⁻⁰⁴	1.15 × 10⁻⁰³
Mn	Adults	2.26 × 10⁻⁰³	1.11 × 10⁻⁰⁴	2.44 × 10⁻⁰⁴
Mo	Children	2.94 × 10⁻⁰³	−	9.68 × 10⁻⁰⁶
Mo	Adults	3.66 × 10⁻⁰⁴	−	2.06 × 10⁻⁰⁶
Ni	Children	1.74 × 10⁻⁰³	6.17 × 10⁻⁰⁹	2.11 × 10⁻⁰⁵
Ni	Adults	2.17 × 10⁻⁰⁴	3.09 × 10⁻⁰⁹	4.50 × 10⁻⁰⁶
Pb	Children	2.59 × 10⁻⁰²	9.46 × 10⁻⁰⁸	4.74 × 10⁻⁰⁴
Pb	Adults	3.23 × 10⁻⁰³	4.74 × 10⁻⁰⁸	1.21 × 10⁻⁰
Sb	Children	3.33 × 10⁻⁰³	8.17 × 10⁻⁰⁸	6.85 × 10⁻⁰⁵
Sb	Adults	4.18 × 10⁻⁰⁴	4.08 × 10⁻⁰⁸	1.56 × 10⁻⁰⁵
Se	Children	8.00 × 10⁻⁰⁴	7.35 × 10⁻¹⁰	−
Se	Adults	1.00 × 10⁻⁰⁴	3.68 × 10⁻¹⁰	−
Sr	Children	3.57 × 10⁻⁰⁴	−	−
Sr	Adults	4.53 × 10⁻⁰⁵	−	−
Zn	Children	2.03 × 10⁻⁰³	7.37 × 10⁻⁰⁹	3.30 × 10⁻⁰²
Zn	Adults	2.50 × 10⁻⁰⁴	3.67 × 10⁻⁰⁹	7.00 × 10⁻⁰³
HI	Children	3.37 × 10⁻⁰¹	2.32 × 10⁻⁰⁴	4.32 × 10⁻⁰²
HI	Adults	4.21 × 10⁻⁰²	1.18 × 10⁻⁰⁴	9.19 × 10⁻⁰³

Table 6

Carcinogenic risk of potentially toxic elements in soil samples
Elements	Age group	Exposure pathways
Elements	Age group	Ingestion (CR)	Inhalation (CR)	Dermal (CR)
As	Children	4.29 × 10⁻⁰⁷	2.71 × 10⁻¹³	2.55 × 10⁻⁰⁷
As	Adults	5.36 × 10⁻⁰⁸	5.59 × 10⁻¹⁴	2.25 × 10⁻⁰⁷
Cr	Children	3.71 × 10⁻⁰⁸	6.89 × 10⁻¹⁰	6.62 × 10⁻⁰⁷
Cr	Adults	4.64 × 10⁻⁰⁹	1.43 × 10⁻¹⁰	5.85 × 10⁻⁰⁷
Cd	Children	3.55 × 10⁻⁰²	1.55 × 10⁻¹¹	−
Cd	Adults	4.45 × 10⁻⁰³	3.86 × 10⁻¹¹	−
Ni	Children	8.42 × 10⁻⁰⁷	9.15 × 10⁻¹²	8.82 × 10⁻⁰⁷
Ni	Adults	1.05 × 10⁻⁰⁷	4.59 × 10⁻¹²	7.80 × 10⁻⁰⁷
Pb	Children	1.12 × 10⁻¹⁰	1.20 × 10⁻¹²	7.27 × 10⁻⁰⁵
Pb	Adults	1.39 × 10⁻¹¹	5.96 × 10⁻¹²	2.89 × 10⁻⁰⁵

3.4 Ecological risk assessments

The results of the ecological risk assessment are presented in Table 4. The distribution of potential ecological risk (${\text{E}}_{\text{r}}^{\text{i}}$) decreasing in the order Hg > Cd > Mo > Pb > As > Cu > Sb > V > Ni > Cr > Mn > Ba > Zn > Ti > Co. The values of ${\text{E}}_{\text{r}}^{\text{i}}$of PTES were below 40, indicating low${ \text{E}}_{\text{r}}^{\text{i}}$ [7]. The results obtained in this study are comparable with values reported in a previous study that ${\text{E}}_{\text{r}}^{\text{i}}$below 40 in soil at Rampal, Bangladesh [43]. However, the values of${ \text{E}}_{\text{r}}^{\text{i}}$ obtained in the present study were lower than those reported in a similar study for Pb, Cd and Pb from Bese, Nigeria [18], and in western Saudi Arabia [33], respectively. The overall ecological risk of the investigated PTEs was below 150, indicating low ecological risk. The results show that Hg contributed 49.54% to the overall ecological risk.

3.4 Health risk assessment

The ADD values of PTEs in soil samples for non-carcinogenic and carcinogenic risk are presented in Tables S5 and S6, respectively. The ADD exposure pathway of the PTEs was greater for ingestion, followed by dermal and inhalation (Table S5). The trend in the ADD values of the investigated PTEs is comparable with similar previous studies [29, 35].

The HQ values are in the subsequent trend Cd > As > Al > Fe Pb > Cr > Mn > Ba > Hg > Sb > Mo > Cu Zn > Ni > Se > Sr > Co, Zn > Cd > Cr > Hg > Mn > As > Pb > Ba > Fe > Sb > Cu > Mn > Mo > Co and Mn > Cr > Ba > Cd > As > Al > Hg > Pb > Co > Sb > Cu > Zn > Ni > Se for ingestion, dermal, and inhalation, respectively, for both children and adults. The estimated HQs are in descending order of ingestion > dermal > inhalation. The greater value ingestion may pose a substantial risk compared with the dermal and inhalation pathways. A higher value of the ingestion pathway has been reported through soil exposure compared with dermal and inhalation [44–49].

The estimated HI values for the investigated PTEs were (6.65 × 10^− 6 to 9.33 × 10^− 2) in children and (8.35 × 10^− 7 to 1.17 × 10^− 2) in adults through ingestion, (7.35 × 10^− 10 to 2.18 × 10^− 4) in children and (3.68 × 10^− 10 to 1.11 × 10^− 4) in adults through inhalation, and (2.75 × 10^− 8 to 3.30 × 10^− 2) and adult (5.83 × 10^− 9 to 7.00 × 10^− 3) children through the dermal pathway. In general, the estimated values obtained were higher for children than for adults, implying the vulnerability of children to PTEs in the soil samples. However, the HI values obtained for ingestion, inhalation, and dermal pathways were less than one (< 1), which signifies that there is negligible or no non-carcinogenic adverse effect likely to occur. Correspondingly, the previous study by Jafari et al. [29] reported that HI < 1 in the soil around the Douroud cement factory, in Iran.

The estimated carcinogenic risk (CR) of PTEs in soil samples is presented in Table 9. The estimated all the investigated PTEs are in children (1.12 × 10^− 10 to 3.55 × 10^− 2) and adults (1.39 × 10^− 11 to 4.45 × 10^− 3) through ingestion, children (2.71 × 10^− 13 to 6.89 × 10^− 10) and adult (5.59 × 10^− 14 to 1.43 × 10^− 10) through inhalation, and children (2.55 × 10^− 7 to 7.27 × 10^− 5) and adult (2.25 × 10^− 7 to 2.89 × 10^− 5) through dermal pathway. The CR of Cd for the ingestion pathway exceeded the permissible limit of (1 × 10^− 6 to 1 × 10^− 4) signifying probable cancer development. Taiwo et al. [49] reported that Cd contributes 82–86% of the total carcinogenic effect. It has been reported that Cd causes persistent toxicity and acute adverse health effects on the kidney, liver, vascular, and immune systems [50]. The higher CR for ingestion obtained in this study is similar to trends reported in similar studies [29, 35, 39].

The assessment of PTEs in the surrounding soil of the cement plant was evaluated using the geochemical load index, ecological and health risk indices. The concentrations of the investigated PTES were lower than the background values. The relative abundance declined in the order of Al > Fe > Mn > Zn > Ti > Ba > Sr > Pb > Cu > V > Cr > Ni > As > Sc > Mo > Hg > Cd > Se > Sb > Co. The geochemical load index revealed that the investigated samples ranged from unpolluted to moderate with PTEs. Ecological risk categorized the investigated soil under the low ecological risk class, with Hg contributing 49.5% to the overall ecological risk. The health risks of ADDs and HQs revealed similar trends for ingestion, dermal, and inhalation pathways for both children and adults. The values of HI for ingestion, inhalation, and dermal pathways obtained are less than one (< 1), which signifies negligible or no non-carcinogenic adverse effects likely to occur. The CR for the ingestion exposure pathway exceeded the permissible limit (1 × 10^− 4) for both children and adults, and Cd was the major contributor to carcinogenic effects, which suggests possible cancer development in residents.

Author Contribution

All authors contributed equally to the design and conception of the study. Mohammad Bashir Sulaiman performed material preparation, data collection, and analysis under supervision of Chukwuma OB Okoye and Jonnie N Asegbeloyin. Mohammad Bashir Sulaiman wrote the first draft of the manuscript; all authors reviewed the manuscript and approved the final manuscript.

The availability of data

The data supporting the findings of this study are available from the corresponding author at reasonable request.

Competing Interest

The authors declare that there are no conflicts of interest.

Liu X, Ouyang W, Shu Y, Tian Y, Feng Y, Zhang T, Chen W. Incorporating bioaccessibility into health risk assessment of heavy metals in particulate matter originated from different sources of atmospheric pollution. Environ Poll. 2019;254:113113. https://doi.org/10.1016/j.envpol.2019.113113.
Zhang L, Yang Z, Peng M, Cheng X. Contamination Levels and the Ecological and Human Health Risks Potentially Toxic Elements (PTEs) in Soil of Baoshan Area, Southwest China. App Sci. 2022;12(3):1693. https://doi.org/10.3390/app12031693.
Yu R, Yuan X, Zhao Y, Hu G, Tu X. Heavy metal pollution in intertidal sediments from Quanzhou Bay, China. J Environ Sci. 2008;20(6):664-669. https://doi.org/10.1016/S1001-0742(08)62110-5.
Gupta RK, Majumdar D, Trivedi JV, Bhanarkar AD. Particulate matter and elemental emissions from a cement kiln. Fuel Proc Techno. 2012;104:343-351. https://doi.org/10.1016/j.fuproc.2012.06.007.
Yang Z, Tang S, Zhang Z, Liu C, Ge X. Characterization of PM₁₀ surrounding a cement plant with integrated facilities for co-processing of hazardous wastes. J Clean Prod. 2018. https://doi.org/10.1016/j.jclepro.2018.03.178.
Liuyi Z, Min G, Jian C, Fumo Y, Huanbo W, Chuan F, Yimin H. Wet Deposition of Trace Metals at a Typical Urban Site in Southwestern China: Fluxes, Sources and Contributions to Aquatic Environments. Sustainability. 2018;10:69. https://doi.org/10.3390/su10010069.
Sulaiman MB, Santuraki AH, Isa KA, Oluwasola OH. Geo-accumulation and Contamination Status of Heavy Metals in Selected MSW Dumpsites Soil in Gombe, Nigeria. Bim J Sci Technol. 2018;2(2):31-41.
Banat KM, Howari FM, Al-Hamada AA. Heavy Metals in Urban Soils of Central Jordan: Should We Worry about Their Environmental Risks? Environ Res. 2005;97:258-273. https://doi.org/10.1016/j.envres.2004.07.002.
Chaw W, Xiao-Chen Z, Li M, Per-fang, Zhi- Young G. Pb, Cu, Zn, and Ni in Vegetables in Relation to Extractable Fractions in Soil, in Sub Urban Areas of Nanjing, China. Poll J Environ Stud. 2007;16(2):199-207.
Shahid M, Bakhat HF, Shah GM, et al. Recent trends in environmental sustainability. Environ Sci Pollut Res. 2023;30:99198-99201. https://doi.org/10.1007/s11356-023-29348-1.
Joshua OO, Liziwe LM, Nomsa GB. Trace Metals in Soil and Plants around a Cement Factory in Pretoria, South Africa. Poll J Environ Stud. 2015;24(5):2087-2093. https://doi.org/10.15244/pjoes/43497.
Oluwasola HO, Olufemi Oluoye, Sulaiman MB, Odewole AO, Abugu OH, Akpomie KD, David MK, Fagorite VI, Maigari AU. Geochemical and health risk assessment of heavy metals concentration in soils around Oke-Ere mining area in Kogi State, Nigeria. Int J Environ Anal Chem. 2021. https://doi.org/10.1080/03067319.2020.1862817.
Uwah EI, Ndahi NP, Ogugbuaja VO. Study of the Levels of Some Agricultural Pollutants in Soils, and Water Leaf (Talinum triangulare) Obtained in Maiduguri, Nigeria. J App Sci Environ Sanit. 2009;4(2):71-78.
Yebpella GG, Magomya AM, Udiba UU, Gandu I, Amana SM, Ugboaja VC, Umana NI. Assessment of Cd, Cu, Mn, and Zn Levels in Soil, Water and Vegetables Grown in Irrigated Farms Along River Kubani, Zaria, Nigeria. J App Environ Bio Sci. 2011;1(5):84-89.
Gupta SK, Ansari FA, Nasr M, Chabukdhara M, Bux, F. Multivariate analysis and health risk assessment of heavy metal contents in foodstuffs of Durban, South Africa. Environ Monit Asess. 2018;190:3. https://doi.org/10.1007/s10661-018-6546-1.
Dashtizadeh M, Kamani H, Ashrafi SD, Panahi AH, Mahvi AH, Balarak D, Hoseini M, Ansari H, Bazrafshan E, Parsafar F. Human health risk assessment of trace elements in drinking tap water in Zahedan city, Iran. J Environ Health Sci Engineer. 2019;17:1163-116. https://doi.org/10.1007/s40201-019-00430-6.
Rafiee A, Delgado-Saborit JM, Sly PD, Quemerais B, Hashemi F, Akbari S, Hoseini M. Environmental chronic exposure to metals and effects on attention and executive function in the general population. Sci Tot Environ. 2020;705. https://doi.org/10.1016/j.scitotenv.2019.135911.
Olatunde KA, Sosanya PA, Bada BS, Ojekunle ZO, Abdussalaam SA. Distribution and ecological risk assessment of heavy metals in soils around a major cement factory, Ibese, Nigeria. Sci Afr. 2019;9:e00496. https://doi.org/10.1016/j.sciaf.2020.e00496.
Sulaiman MB, Santuraki AH, Auwal MA, Ezenobi UV, Gimba MA, Akinlotan OO. Concentrations and health risk assessment of heavy metals in medicinal herbs from Northern Nigeria. French-Ukra J. Chem. 2022;9(1): 9-20. https://doi.org/10.17721/fujcV10I2P9-21.
Agbede OT, Taiwo AM, Adeofun CO, Adetunji MT, Azeez JO, Arowolo TA. Assessing the pollution effect of cement dust emission on the soil quality around Ewekoro cement factory, southwestern Nigeria. Environ Foren. 2022. https://doi.org/10.1080/15275922.2022.2125120.
Yahaya T, Umar A, Abubakar M, Abdulazeez A, Musa B, Ibrahim YY, Jibrin AH. Heavy Metals in the Soil Around a Cement Company in Sokoto, Northwestern Nigeria Pose Health Risks. Indust Dom Was Manage. 2023;3(1):17-26. https://doi.org/10.53623/idwm.v3i1.183.
Sulaiman MB, Okoye COB, Asegbeloyin JN Ihedioha JN. Chemical characteristics and health risk assessment of potential toxic elements in atmospheric PM₁₀ around Ashaka cement factory, Gombe, Nigeria. French-Ukra J Chem. 2021;9(1):72-82. https://doi.org/10.17721/fujcV9I2P72-82.
Xie XJ, Cheng HX (2001) Global Geochemical Mapping and its Implementation in the Asia-Pacific Region. Appl Geochem. 16:1309-1321. https://doi.org/10.1016/s0883-2927(01)00051-8.
Obayomi OO, Sulaiman MB, Oluwasola, HO, Ali SB, Akpomie KG, Odewole OA, David MK. Ecological Risk Assessment of Potentially Toxic Elements in the Bottom Sediments of a Stream in Oke-Ere, Kogi State, North Central Nigeria. Int J Environ Sci Techno. 2023. doi.org/10.1007/s13762-023-04851-7.
Nguyen TH, Hoang HNT, Bien NQ, Tuyen LH, Kim KW. Contamination of heavy metals in paddy soils in the vicinity of Nui Phao multi-metal mine, North Vietnam. Environ Geochem Health. 2020. https://doi.org/10.1007/s10653-020-00611-5.
Birke M, Rauch U. Geochemical investigation of the urban area of Berlin. Federal Institute of Geosciences and Natural Resources, Branch Office Berlin. 1994;30.
Grzebisz W, Cieśla L, Komisarek J Potarzycki J. Geochemical Assessment of Heavy Metals Pollution of Urban Soils. Poll J Environ Stud. 2002;11:5. https://doi.org/10.1007/s10653-016-9841-1
Hakanson L. An ecological risk index for Aquatic pollution control. A Sedimentological Approach. Water Res. 1980;14:975-1101. http://doi.org/10.1016/0043-1354(80)90143-8.
Jafari A, Ghaderpoori M, Kamarehi B, Abdipour H. Soil pollution evaluation and health risk assessment of heavy metals around Douroud cement factory, Iran. Environ Earth Sci. 2019;78:250. https://doi.org/10.1007/s12665-019-8220-5.
USEPA, Supplemental Guidance for Developing Soil Screening Levels for Superfunda. Sites. OSWER 9355.424. Office of Solid Waste and Emergency Response. 2001.
USEPA, Risk Assessment Guidance for Superfund Volume I: Human Health Evaluation Manual (Part F, Supplemental Guidance for Inhalation Risk Assessment). Office of Superfund Remediation and Technology Innovation, Washington, D.C. 2009.
Turekian KK, Wedepohl KH. Distribution of the elements in some major units of the Earth's crust. Bull Geol Soc Amer. 1961;72(2):175-192. https://doi.org/10.1130/0016-7606.
El-Sherbiny MM, Ismail AI, EL-Hefnawy ME. A preliminary assessment of potential ecological risk and soil contamination by heavy metals around a cement factory, western Saudi Arabia. Open Chem. 2019;17:671-684. https://doi.org/10.1515/chem-2019-0059.
Awuah PB, Adjaottor AA, Gikunoo E, Atthur EK, Agymang FO, Baah DS. Dust deposition and associated heavy metal contaminaton in the neighborhood of a cement production plant at Konongo, Ghana. J Chem. 2022. https://doi.org/10.1155/ 2022/6370679.
Das D, Hasan M, Howladar MF. Topsoil heavy metals status and potential risk assessment around the cement factories in Chhatak, Bangladesh. Environ Dev Sustain. 2023;25:5337-5362. https://doi.org/10.1007/s10668-022-02269-8.
Okoro HK, Orimolade BO, Adebayo GB, Akande BA, Ximba BJ, Ngila JC. An Assessment of Heavy Metals Contents in the Soil around a Cement Factory in Ewekoro, Nigeria Using Pollution Indices. Poll J Environ Stud. 2017;26(1):221-228. https://doi.org/10.15244/pjoes/62389.
Silva TAC, Paula, MJ, Silva WS, Lacorte GA. Deposition of Potentially Toxic Metals in the Soil from Surrounding Cement Plants in a Karst Area of Southeastern Brazil. Conservation. 2021;1:137-150. https://doi.org/10.3390/conservation1030012.
Omolara V, Akpambang E, Ebuzeme GC, Akinola JO. Heavy metal contamination of topsoil around a cement factory-A case study of Obajana Cement Plc. Enviro Poll Bioavai. 2022;34:(1):12-20. https://doi.org/10.1080/26395940.2021.2024090.
Parlak, M, Everest T, Tunçay T. Spatial distribution of heavy metals in soils around cement factory and health risk assessment: a case study of Canakkale-Ezine (NW Turkey). Environ Geochem Health. 2023;45:5163-5179. https://doi.org/10.1007/s10653-023-01578-9.
Ajeel MA, Ajeel AA, Nejres AM, Salih RA. Assessment of Heavy Metals and Related Impacts on Antioxidants and Physiological Parameters in Oil Refinery Workers in Iraq. J health poll. 2021;11(31):210907. https://doi.org/10.5696/2156-9614-11.31.210907.
Prakash MM and Dagaonkar A. Application of cluster analysis of physic-chemical parameters of Munji sugar atlab, Dhar (Madhya Pradesh, India). Recent Res Sci Technol. 2011;3(1):41-50.
Amiri H, Daneshvar E, Azadi S, Azadi S. Contamination level and risk assessment of heavy metals in the topsoil around cement factory: A case study. Environ Eng Res. 2022;27(5):210313. https://doi.org/10.4491/eer.2021.313.
Parvez MS, Nawshin S, Sultana S, Hossain MS, Khan MHR, Habib A, Nijhum ZT, Khan R. Evaluation of Heavy Metal Contamination in Soil Samples around Rampal, Bangladesh. ACS Omega. 2023; 8(18):15990-15999. https://doi.org/10.1021/acsomega.2c07681.
Vanden Berg R. Human exposure to soil contamination: a qualitative and quantitative analysis towards proposals for human toxicological intervention values. RIVM Report no. 725201011. Bilthoven, The Netherlands: National Institute of Public Health and Environmental Protection (RIVM). 1995.
Ma J, Singhirunnusorn W. Distribution and health risk assessment of heavy metals in surface dusts of Maha Sarakham municipality. Procedia-Soc Behav Sci. 2012;50:280–293.https://doi.org/10.1016/j.sbspro.2012.08.034.
Du YR, Gao B, Zhou HD, Ju XX, Hao H, Yin S. Health risk assessment of heavy metals in road dusts in urban parks of Beijing, China. Procedia Environ Sci. 2013;18:299-309. https://doi.org/10.1016/j.proenv.2013.04.039.
Olujimi OO, Oputu O, Fatoki O, Opatoyinbo OE, Aroyewun OA, Baruani J. Heavy Metals Speciation and human health risk assessment at an illegal gold mining site in Igun, Osun State, Nigeria. J Health Pollut. 2015;5(8):19-32. https://doi.org/10.5696/i2156-9614-5-8.19.
Taiwo AM, Awomeso JA, Taiwo OT. Assessment of health risks associated with road dusts in major traffic hotspots in Abeokuta metropolis, Ogun state, southwestern Nigeria. Stoch Environ Res Risk Assess. 2017;31:431-447. https://doi.org/10.1007/s00477-016-1302-y.
Taiwa AM, Oladotun OR, Gbadebo, Alegbeleye. Pollution, Ecological and Health Risk Assessment of Heavy Metals Remediated Soils by Compost Fortified with Natural Coagulants. Chem Afr. 2022;6:1579-1593. https://doi.org/10.1007/s42250-022-00564-5.
Jurowski K, Kro´sniak M. The Toxicological Assessment of Content and Exposure of Heavy Metals (Pb and Cd) in Traditional Herbal Medicinal Products with Marshmallow Root (Althaea officinalis L., radix) from Polish Pharmacies. Toxics. 2022;10:188. https://doi.org/10.3390/toxics10040188.

No competing interests reported.

SupplementaryMaterial.docx

Geochemical, ecological, and health risk assessment of potentially toxic elements (PTEs) in the surrounding soil of a cement plant

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Abstract

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1 Introduction

2 Materials and Methods