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High cassava production and low dietary cyanide exposure in mid-west Nigeria

Published online by Cambridge University Press:  02 January 2007

Adeyinka Onabolu*
Affiliation:
International Institute of Tropical Agriculture (IITA), c/o L.W. Lambourn & Co., 26 Dingwall Road, Croydon CR9 3EE, UK Division of International Health, Department of Public Health Sciences, Karolinska Institute, SE-171 76 Stockholm, Sweden
Mpoko Bokanga
Affiliation:
International Institute of Tropical Agriculture (IITA), c/o L.W. Lambourn & Co., 26 Dingwall Road, Croydon CR9 3EE, UK
Thorkild Tylleskär
Affiliation:
Department of Medicine, Nutrition Unit, Uppsala University, Dag Hammarskjölds väg 21, SE-752 37 Uppsala, Sweden
Hans Rosling
Affiliation:
Division of International Health, Department of Public Health Sciences, Karolinska Institute, SE-171 76 Stockholm, Sweden
*
*Corresponding author: Email aonabolu@hotmail.com
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Abstract

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Objective:

To investigate if high cassava production levels indicate high consumption and high dietary cyanide exposure in three villages situated within the area of Nigeria with higher cassava production than predicted by a geographic model for cassava production in Africa.

Design:

Exploratory assessment of: cassava production and processing by qualitative research methods and quantification of residual cyanogens in products; cassava consumption by food frequency and weighed food records and dietary cyanide exposure by urinary thiocyanate and linamarin.

Setting:

Rural communities of Afuze, Ebue and Ofabo in mid-west Nigeria.

Subjects:

110 subjects from 42 households in three villages for food frequency interviews; 118 subjects in nine Ofabo households for weighed food records.

Results:

Cassava cultivation was reported to have increased in the preceding 20 years. It was consumed daily by 37 (88%) households, but its mean contribution to daily energy intake was only 13% (SD = 10). The range of residual cyanogens in cassava foods was 0 to 62 mg HCN equivalent/kg dry weight (dw). Ten samples (19%) had levels above the 10 mg HCN equivalent/kg dw FAO/WHO safety limit. Mean urinary thiocyanate and linamarin were 51 (SD = 35) and 20 (SD = 11) μmol/L, indicating low cyanogen intake and dietary cyanide exposure.

Conclusion:

High cassava production levels did not result in high consumption and high dietary cyanide exposure levels, therefore cassava production levels cannot be used to predict consumption or cyanide exposure levels in the study area. A large part of the production is explained by intensive sales.

Type
Research Article
Copyright
Copyright © CABI Publishing 2001

References

1Allem, A. The origin of Manihot esculenta Crantz (Euphorbiaceae). Gen. Res. Crop Evol. 1994; 41: 133–50.CrossRefGoogle Scholar
2Conn, ECyanogenic compounds. Annu. Rev. Plant Physiol. 1980; 31: 433–51.CrossRefGoogle Scholar
3Bokanga, M. The cyanogenic potential of cassava. In: Root Crops for Food Security in Africa, Fifth Triennial Symposium of the International Society for Tropical Root Crops—Africa Branch, Uganda, 1994, 1992. Ibadan, Nigeria: ISTRC-AB.Google Scholar
4Dufour, D. Effectiveness of cassava detoxification techniques used by indigenous peoples in NW Amazonia. Intersciencia. 1989; 14: 8691.Google Scholar
5Vasconcelos, A, Twiddy, D, Westby, A, Reilly, P. Detoxification of cassava during gari preparation. Int. J. Food Sci. Technol. 1990; 25: 198203.CrossRefGoogle Scholar
6Westby, A, Choo, B. Cyanogen reduction during lactic acid fermentation of cassava. Acta Hortic. 1994; 375: 209–15.CrossRefGoogle Scholar
7Onabolu, A, Bokanga, M, Rosling, H. Cassava processing in a Nigerian community affected by a neuropathy attributed to dietary cyanide exposure. Trop. Sci. 1999; 39: 129–35.Google Scholar
8Mlingi, N, Poulter, N, Rosling, H. An outbreak of acute intoxications from consumption of insufficiently processed cassava in Tanzania. Nutr. Res. 1992; 12: 677–87.CrossRefGoogle Scholar
9Brimer, L, Rosling, H. Microdiffusion method with solid state detection of cyanogenic glycosides from cassava in human urine. Food Chem. Toxicol. 1993; 31: 599603.CrossRefGoogle ScholarPubMed
10Carlsson, L, Mlingi, N, Juma, A, Ronquist, G, Rosling, H. Metabolic fate in humans of linamarin in cassava flour ingested as stiff porridge. Food Chem. Toxicol. 1999; 37: 307–12.CrossRefGoogle ScholarPubMed
11Schulz, V. Clinical pharmacokinetics of nitroprusside, cyanide, thiosulphate and thiocyanate. Clin. Pharmacokinetics 1984; 9: 239–51.CrossRefGoogle ScholarPubMed
12Rosling, HMeasuring effects in humans of dietary cyanide exposure from cassava. Acta Hortic. 1994; 375: 271–83.CrossRefGoogle Scholar
13Tylleskär, T, Banea, M, Bikangi, N, Cooke, R, Poulter, N, Rosling, H. Cassava cyanogens and konzo, an upper motoneuron disease found in Africa. Lancet 1992; 339: 208–11.CrossRefGoogle ScholarPubMed
14Akintonwa, A, Tunwashe, OL. Fatal cyanide poisoning from cassava-based meal. Hum. Exp. Toxicol. 1992; 11: 47–9.CrossRefGoogle ScholarPubMed
15Rosling, H, Tylleskar, T. Konzo. In: Shakir, R, Newman, P, Poser, C, eds. Tropical Neurology. London: Saunders, 1996; 353–64.Google Scholar
16Monekosso, GLClinical epidemiologic observations on an ataxic syndrome in Western Nigeria. Trop. Geogr. Med. 1964; 4: 316–23.Google Scholar
17Osuntokun, B, Monekosso, G, Wilson, J. Relationship of a degenerative tropical neuropathy to diet report of a field survey. Br. Med. J. 1969; 1: 547–50.CrossRefGoogle ScholarPubMed
18Delange, F, Ekpechi, L, Rosling, H. Cassava cyanogenesis and iodine deficiency disorders. Acta Hortic. 1994; 375: 289–93.CrossRefGoogle Scholar
19Carter, S, Jones, P. A model of the distribution of cassava in Africa. Appl. Geogr. 1993; 13: 353–71.CrossRefGoogle Scholar
20Tylleskär, T, Banea, M, Bikangi, N, Fresco, L, Persson, , Rosling, H. Epidemiological evidence from Zaire for a dietary aetiology of konzo, an upper motor neuron disease. Bull. World Health Org. 1991; 69: 581–90.Google ScholarPubMed
21Nweke, F. COSCA Project Description. Ibadan: International Institute of Tropical Agriculture, 1988.Google Scholar
22Carter, S, Jones, P. COSCA Site Selection Procedure. Ibadan: International Institute of Tropical Agriculture, 1988.Google Scholar
23Ugwu, B, Ajobo, O, Orkwor, G. In: Nweke, F, Lynam, J, Prudencio, C, eds. Status of Data on Cassava in Major Producing Countries of Africa: Cameroon, Cote d'Ivoire, Ghana, Nigeria, Tanzania, Uganda and Zaire. Vol. COSCA Working Paper No. 3. Ibadan: International Institute of Tropical Agriculture, 1989.Google Scholar
24Folayan, S. COSCA Village Level Survey Database. Ibadan: International Institute of Tropical Agriculture, 1993.Google Scholar
25Willet, W, Sampson, L, Stampfer, M. Reproducibility and validity of a semi-quantitative food frequency questionnaire. Am. J. Epidemiol. 1985; 122: 5165.CrossRefGoogle Scholar
26Bingham, SA, Gill, C, Welch, A, et al. Comparison of dietary assessment methods in nutritional epidemiology: weighed records v. 24 h recalls, food-frequency questionnaires and estimated-diet records. Br. J. Nutr. 1994; 72: 619–43.CrossRefGoogle ScholarPubMed
27Essers, A, Bosveld, M, Van der Grift, R, Voragen, A. Studies on the quantification of specific cyanogens in cassava products and introduction of a new chromogen. J. Sci. Food Agric. 1993; 63: 287–96.CrossRefGoogle Scholar
28Ikediobi, C, Onyia, G, Eluwah, G. A rapid and inexpensive enzymatic assay for total cyanide in cassava and cassava products. Agric. Biol. Chem. 1980; 44: 2803–9.Google Scholar
29Carlsson, L, Mlingi, N, Ronquist, G, Rosling, H. A specific and sensitive method for the determination of linamarin in urine. Nat. Toxins. 1995; 3: 378–82.CrossRefGoogle ScholarPubMed
30Lundquist, P, Kågedal, B, Nilsson, L. An improved method for the determination of thiocyanate in plasma and urine. Eur. J. Clin. Chem. Clin. Biochem. 1995; 33: 343–9.Google ScholarPubMed
31Lundquist, P, Mårtensson, J, Sörbo, B, Öhman, S. Turbidimetry of inorganic sulfate, ester sulfate, and total sulfur in urine. Clin. Chem. 1980; 26: 1178–81.CrossRefGoogle ScholarPubMed
32FAO/WHO. Codex standard for edible cassava flour—African Regional standard. Rome: FAO–WHO Food Standards Programme, 1992.Google Scholar
33Banea, M, Poulter, N, Rosling, H. Shortcuts in cassava processing and risk of dietary cyanide exposure in Zaire. Food Nutr. Bull. 1992; 14: 137–43.CrossRefGoogle Scholar
34Banea, M, Bikangi, N, Nahimana, G, Nunga, M, Tylleskar, T, Rosling, H. High prevalence of konzo associated with a food shortage crisis in the Bandundu region of Zaire. Ann. Soc. Belge Med. Trop. 1992; 72: 295309.Google ScholarPubMed
35Banea-Mayambu, JP, Tylleskar, T, Gitebo, N, Matadi, N, Gebre-Medhin, M, Rosling, H. Geographical and seasonal association between linamarin and cyanide exposure from cassava and the upper motor neurone disease konzo in former Zaire. Trop. Med. Int. Health. 1997; 2: 1143–51.CrossRefGoogle ScholarPubMed
36Banea-Mayambu, J, Bikangi, N, Tylleskär, T, Rosling, H. High cassava consumption without cyanide exposure in Kinshasa, in former Zaire. Ecol. Food Nutr. 1998; 37: 363–7.CrossRefGoogle Scholar
37Mlingi, N, Assey, V, Swai, A, McLarty, D, Karlén, H, Rosling, H. Determinants of cyanide exposure from cassava in a konzo-affected population in northern Tanzania. Int. J. Food Sci. Nutr. 1993; 44: 137–44.CrossRefGoogle Scholar
38Nweke, F. Cassava distribution in Africa. Ibadan: Collaborative Study on Cassava in Africa (COSCA), 1992.Google Scholar
39Cliff, J. Cassava safety in times of war and drought in Mozambique. Acta Hortic. 1994; 375: 373–8.CrossRefGoogle Scholar
40Banea, M. Cassava processing, dietary cyanide exposure and konzo in Zaire. Uppsala University, 1993.Google Scholar
41Mlingi, N, Abrahamsson, M, Yuen, J, Gebre-Medhin, M, Rosling, H. Low cyanide exposure from consumption of cassava in Dar Es Salaam, Tanzania. Nat. Toxins 1998; 6: 6772.3.0.CO;2-9>CrossRefGoogle ScholarPubMed
42Lundquist, P, Martensson, J, Sorbo, B. Ohman, S. Method for determining thiocyanate in serum and urine. Clin. Chem. 1979; 25: 678–81.CrossRefGoogle ScholarPubMed