9b

Environ Geochem Health (2007) 29:163–167 DOI 10.1007/s10653-006-9068-7

ORIGINAL PAPER

The Sagamu cement factory, SW Nigeria: Is the dust generated a potential health hazard? Akinlolu F. Abimbola Æ Olusegun O. Kehinde-Phillips Æ Akinade S. Olatunji

Published online: 26 January 2007 Ó Springer Science+Business Media B.V. 2007

Abstract The aim of this study was to assess the heavy metal content of the dust generated by the Sagamu cement factory and its attendant health hazards on the immediate environment, especially on the inhabitants of the area. A total of 25 samples were collected and analyzed using inductively coupled plasma-optical emission spectrometry. Records of medical ailments associated with heavy metal toxicity were also compiled from the Obafemi Awolowo Teaching Hospital situated in the town.The results for some of the selected heavy metals showed the following pattern: limestone: Cd (n.d.-1.7 ppm), Pb (42–48 ppm), Cu (3.0–11 ppm), Zn (7.0–53 ppm) and Ni (3.0–8.0 ppm); shale: Cd (0.3–1.1 ppm), Pb (17–22 ppm), Cu (2.0–11 ppm), Zn (17–147 ppm) and Ni (3.0–18 ppm); dusts: Cd (0.5–0.7 ppm), Pb (32–52 ppm), Cu (2–16 ppm), Zn (5–152 ppm) and Ni (2–17 ppm); soils: Cd (0.5–1.1 ppm), Pb (28–49 ppm), Cu (22–35 ppm), Zn (43–69 ppm) and Ni (13.0–17 ppm). High levels of heavy metals were found in the rocks and soils. We propose that the high levels of metals in the dust and soil were acquired from the raw A. F. Abimbola (&) Department of Geology, University of Ibadan, Ibadan, Nigeria e-mail: [email protected] O. O. Kehinde-Phillips
A. S. Olatunji Department of Earth Sciences, Olabisi Onabanjo University, Ago-Iwoye, Nigeria

materials used by the cement factory and from active industrial discharge from this same factory. Medical records and the current health situation of the local residents in the study area reveal that there have been increases in the prevalence of diseases linked to heavy metal toxicity in the environment, especially those related to dust generation. Keywords Cement factory
Dust
Heavy metals
Medical reports
Sagamu

Introduction During the past two decades the study of the links between the geochemistry of earth materials and human and animal health has received much attention (Nriagu, 1981; Bowie & Thornton, 1985; Thornton, 1986, 1988; Lag, 1989; Fergusson, 1990; Appleton, Fuge, & McCall, 1996; Fordyce et al., 1999). Heavy metals are the main source of trace element toxicity in the environment because most organisms are not adapted to dealing with them when they occur locally at concentrations higher than the normal levels that can be tolerated in the alimentary canal during the ingestion of food and water and inhalation of dusts (Sharma & Sharma, 1997). According to Xiu (1996), only ten elements can be considered to be essential to the proper functioning of the human body. A dietary

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deficiency of any of these elements poses health problems, while an excess of other elements may lead to toxicity and associated health problems. The quest for industrialization and job creation in developing countries has led to massive efforts to attract heavy industries with high pollution potential. This recalls Krauskpof’s (1967) assertion that the deposition of aerosol particles from urban and industrial air pollution in most industrialized countries is a major source of enhanced metal concentrations in the soils and foliage of urban areas. Nigeria is a country abundantly rich in limestone deposits. For the past 30 years these deposits have been exploited for making cement. The cement works on which this study is based is located about 80 km north of Lagos (Fig. 1) and is owned by a local subsidiary of the Lafarge Group. It generates large quantities of dust in its Fig. 1 Location of Sagamu Cement Factory, near Lagos, Nigeria

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operations, and this dust settles on the soil, vegetation, crops and roofs of houses inhabited by workers and residents of the area. The aim of this preliminary study was to ascertain the heavy metal composition of the dusts generated by the Sagamu Cement Factory and to assess the attendant environmental and health effects, especially those on the inhabitants of the area.

Study area The Sagamu Works of the West African Cement Company (a local subsidiary of the Lafarge Group) started operations at its present location about 25 years ago. The Sagamu area falls within the eastern Dahomey Basin of southwestern Nigeria. The

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global average values. The concentrations of Cd, Pb and Zn in all four sample types (limestone, shale, soil and dusts) were generally higher than their global means, while those of Cu and Ni (with the exception of the limestone samples) were not (Table 1). These results show elevated values for selected heavy metals in the rock samples exposed at Sagamu. It is assumed that the heavy metals found in the rocks are released into the environment as dusts generated during cement production. This would explain the enhanced concentration of heavy metals in the dust samples (Table 1 and Fig. 2). Soils from around the cement factory were also analyzed for these heavy metals in order to determine the fate of the dust. The values for these heavy metals in the soil samples (Tables 1 and 2, Fig. 2) are higher than those obtained from crustal rocks, as reported by Rose, Hawkes, & Webb (1979). This is especially so for Cd and Pb. The source of these metals in the soil samples may be linked to the settling of the dusts rich in heavy metals derived from cement production, especially Pb and Zn. The evaluation of the metal ratio of the soil to the crustal average revealed that the trace element content of the soil surrounding the cement factory has been enhanced in Cd, Pb, Cu, Zn and Ni from the dust derived from the cement works. To ascertain the degree to which these metals have impacted on the health of the inhabitants of the study area, we obtained the medical reports from the Obafemi Awolowo Teaching Hospital for those diseases commonly associated with the effects of these heavy metals. The medical records

rocks are Late Cretaceous to Early Tertiary in age (Jones & Hockey, 1964; Adegoke, 1969; Agagu, 1985), the sedimentary units within the basin having been grouped into the Abeokuta Group, Imo Group, Oshoshun Formation, Ilaro Formation and the Coastal Plain Sands and Tertiary Alluvium (Adegoke & Omatsola, 1981; Agagu, 1985). The raw materials for the cement operations are mined from the Imo Group, which is divided into the limestone-dominated Ewekoro Formation and the shale-dominated Akinbo Formation. Materials and methods In this study, seven limestone samples, two shale samples, five soil samples and ten dust samples were collected in the vicinity of the cement works and analyzed for their heavy metal content using inductive coupled plasma-optical emission spectroscopy (ICP-OES) at the Activation Laboratories Limited, Ontario Canada. Medical reports for the most recent 5-year period (2000–2004) were also obtained from the Obafemi Awolowo Teaching Hospital located in the town. The medical reports were used to compare the incidence of reported diseases and ailments in the study area with the dust generated from the cement works. Results and discussions The results of the heavy metal analyses of the various sample types were compared with their Table 1 Summary of analyses Sample

Limestonea Shalea Dust Soilb a

Cd

Pb

Zn

Cu

Ni

This study

Global average

This study

Global average

This study

Global average

This study

Global average

This study

Global average

n.d–0.8c 0.3–1.1 0.5–0.7 0.5–1.1

0.028 0.3

42–49 17–22 32–52 28–49

5.7 20

7–53 17–147 5–152 43–69

20 90

3–10 n.d-11 2–16 11–35

5.5 50

3–14 3–14 2–17 13–48

7 68

0.2

14

75

50

80

Krauskpof (1967)

b

Rose et al. (1979)

c

n.d., Below detection limit. All values are in ppm

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liver diseases and cancer cases, with reported cases of respiratory/lung diseases and heart diseases doubling between 2000 and 2004 (Fig. 3) and those of cancer trebling. The inferred link between the cement factory and the increased incidence of these diseases is supported by the fact that the Transfer Factor (the ratio of the content of an element in dust to its average concentration in the dominant rock used for cement production, i.e. limestone) is >1 for Pb.

90 80

LIME STONE SHALE DUST SOIL

60 50

40 30 20

Conclusion

10

The numbers of reported cases of lung, heart, skin, kidney/liver ailments and cancer in the area around the Sagamu Cement Works are striking. However, there is no conclusive evidence to link the increase in the number of reported cases to the heavy metal content of the dusts produced by the factory. However, the positive correlation between the two is unlikely to be coincidental. Future studies should include the collection and analysis of blood and tissue samples from both inhabitants and livestock within the study area with the aim of demonstrating causal links.

0 Cd

Cu

Ni

Pb

Zn

HEAVY METALS

Fig. 2 Average abundance of heavy metals in analyzed samples from the Sagamu area

for the period 2000–2004 show that there has been a steady increase in reported cases of respiratory/ lung diseases, heart diseases, skin diseases, kidney/ Table 2 Concentration of heavy metals in the samples of geo-material collected in the study area Sample description

Limestone Limestone Limestone Limestone Limestone Limestone Limestone Shale Shale Dust Dust Dust Dust Dust Dust Dust Dust Dust Dust Soil Soil Soil Soil Soil a

Heavy metals (ppm) Cd

Cu

Ni

Pb

Zn

n.da n.d 0.7 0.7 n.d n.d 0.8 1.1 0.3 0.5 0.8 0.9 1.2 0.9 0.7 0.6 1.2 1.2 1.0 0.6 0.9 1.1 0.5 0.5

7 3 10 7 6 9 10 n.d 11 3 4 6 2 9 15 14 16 13 10 35 24 22 22 27

3 6 6 9 14 8 8 14 48 3 5 8 10 14 12 17 12 11 10 15 17 14 13 15

49 45 49 49 45 42 48 17 22 32 35 40 45 47 52 51 48 49 47 29 43 34 28 49

7 13 23 26 53 29 24 17 147 42 55 64 83 156 30 42 32 35 43 45 69 67 43 58

n.d., Below detection limit

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45 Respiratory Diseases

40

Heart Diseases Skin Diseases

35

Kidney/Liver Diseases Cancer Diseases

Number of Occurrence.

AVERAGE COMPOSITION

70

30 25 20 15 10 5 0 2000

2001

2002

2003

2004

Year

Fig. 3 Prevalence of diseases in the Sagamu area, Nigeria commonly associated with the effects of heavy metals as mined from local medical records

Environ Geochem Health (2007) 29:163–167

References Adegoke, O. S. (1969). Eocene stratigraphy of southwestern Nigeria. Mineral Memoir, 69, 23–46. Adegoke, O. S., & Omatsola, M. E. (1981). Tectonic evolution and Cretaceous stratigraphy of the Dahomey Basin. Journal Mining and Geology, 8(1), 130–136. Agagu, O. K. (1985). A geological guide to bituminous sediments of southwestern Nigeria.Unpublished report of Department of Geology, Ibadan: University of Ibadan, 16. Appleton, J. D., Fuge, R., & McCall, G. J. H. (1996). Environmental geochemistry and health with special reference to developing countries. Geological Society Special Publication No.113, 37 pp. Bowie, S. H. U., & Thornton, I. (1985). Environmental geochemistry and health. Lancaster: D Reidel Publishing Company, 140. Fergusson, J. E. (1990). The heavy elements. Chemistry, environmental impacts and health effects. Oxford: Pergamon Press, 614. Fordyce, F. M., Plant, J., Smith, B., Appleton, D., Johnson, S. P., & Williams, L. (1999). Environmental geochemistry and health - Global Perspectives. In: Proceedings of ICSU-IGU workshop on setting an agenda on health and the environment. (pp. 1–13) Health and Environmental Resources, Mona, Jamaica (Nov. 12–14, 1999).

167 Jones, H. A., & Hockey, R. O. (1964). The geology of part of southwestern Nigeria. Geological Survey of Nigeria Bulletin, 13, 56–77. Krauskpof, K. B. (1967). Introduction to Geochemistry. New York: McGraw-Hill, 721. Lag, J. (1989). Excess and deficiency of trace elements in relation to human and animal health in arctic and subarctic regions. Norwegian Academy of Science Letters, 3–15. Nriagu, J. O. (1981). Cadmium in the Environment. Part II: Health Effects. New York: Wiley, 584. Rose, A. W., Hawkes, E. H., & Webb, J. S. (1979). Geochemistry in mineral Exploration. (2nd ed.) London: Academic Press, 657. Sharma, R. K., & Sharma, U. (1997). Physiological perspectives of Copper. Report of Department of Zoology, India: Kunishetra University, 698–713. Thornton, I. (1986). Geochemistry and health. In: Proceedings of the 1st symposium on geochemistry and health. Northwood: Science Reviews Ltd, 1–3. Thornton, I. (1988). Geochemistry and health. In: Proceedings of the 2nd symposium on geochemistry and health. Northwood: Science Reviews Ltd, 1–2. Xiu, Y. M. (1996). Trace elements in health and diseases. Biomedical and Environmental Sciences. Department of Trace Element Nutrition. Chinese Academy of Preventive Medicine, China: Beijing, 130–136.

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