Die Nahrung 30 (1986) 5, 565-567

University of Valencia, Faculty of Pharmacy. Department of Food Chemistry, Toxicology and Analytical Chemistry, Valencia. Spain

Cobalt content of foods and diets in a Spanish population

(Short communication)

R. BARBERA and R. FARE&

Introduction

The WHO Expert Committee on Food Contaminants has pointed out the need of determining the content of foods in trace elements in order to ascertain their contribution to the total intake of oligoelements through the diet. Since the contents in trace elements depend on the environmental features, it is necessary to carry out systematic determinations of trace elements in foods of local origin in order to know the exposure level of population.

This work intends to study the cobalt contribution-through the diet. The element intake is calculated from the cobalt content in raw foods after elimination of the non-eatable moiety by flame atomic absorotion spec- troscopy, after formation of a chelate with ammonium pyrrolidine dithiocarbamate (APDC) and extraction with 4-methyl-2-pentanone (MIBK) according to a procedure developed and verified in a previous paper [I] .

Materials and methods

The dietary intake by the population is determined by to ways: a) From the National Food Survey Tables [2]; b) From a dietary survey performed according to the market basket method for a 7 days period.

The number of surveys has been 400 corresponding to a population of 865 people. The distribution ac- cording to age is the following: 5 years - 5; 6 to 10 - 7 ; 11 to 15 -- 12; 16 to 20 - 80; 21 to 30 - 525; 31 to 40 - 19; 41 to 50 - 89; 51 to 60 - 98; 61 to 70 - 21; older than 70 - 9.

The values for the dietary intake estimated from the National Food Survey Tables and from the market basket method are summarized in Table I . Foods were classified into 10 groups. namely: 1 - Cereals; 2 - Meat and poultry; 3 - Fish; 4 -- Oils and fats; 5 - Eggs; 6 - Fruits; 7 - Vegetables; 8 - Potatoes; 9 -- Milk and dairy products; 10 - Drinks. The average value of cobalt content is determined for each food group. These average values together with the intakcs estimated for every food group allow to calculate the total cobalt intake. The percentage of food wasted during processing is also determined so that it is possible to know the net intake of both food and hobalt. The cobalt contribution by different food groups, as well as the total intake are summarized in Table 1.

Discussion

The National Food Survey Tdbles and the dietary surveys provide very similar estimations of the dietary intake. However it must be pointed out that, according to the dietary surveys, milk and dairy products are among the foods of higher intake, whereas the National Food Survey Tables show, on the other hand, a lower intake of cereals and fruits balanced by the corresponding increase in the intake of vegetables and potatoes.

This data allow to determine the cobalt contribution by each dietary food group. The higher cobalt percen- tages are contributed by meat, cereals and poultry. this being determined by both the value of the intake for this food group and its cobalt content. Although the intake of milk and dairy products is high, the foods contribute a low percentage of total cobalt due to the low content in this element.

566 Die Nahrung 30 (1986) 5

Table 1 Cobalt content and population dietary intake _____ __ __ Food groups Average conc Dietary intake (g person and day)

of c o IMM A B

Total Net Total Net

I. Cereals 2. Meat and poultry 3. Fish 4. Oils and fats 5 . Eggs 6. Fruits 7. Vegetables 8. Potatoes 9. Milk and dairy PI

10. Drinks 1 I . Drinking water

0.026 0.021 0.02 1 0.015 0.010 0.010 0.01 1 0.019

mducts 0.004 0.007

. 0.004

207 207 213 178

57 41 52 52 41 42

284 213 415 348 266 226 361 361 133 133

243 185 54 47 47

278 279 94

315 86

1000

243 I54 45 47 42

209 234

80 315 86

1000

total

Cobalt net daily intake "1

A B

5.38 6.32 3.74 3.25 0.99 0.95 0.78 0.70 0.42 0.42 2.13 2.08 3.83 2.58 4.29 1.52 1.44 1.26 0.93 0.60

4.00

25.02 23.68 ~ __

A - Data from National Food Survey Tables; B - Data from dietary survey In the calculation of the net dietary intake the waste percentages for each have been calculated: meat and poultry 16.5",. fish 17.1 n i , eggs lO.Oo/o, fruits 25.0%, vegetables 16.1 %,and potatoes 15.0%. Theseare aver- age values of the percentages of waste food for the different foods included in the same group.

The cobalt average intakes estimated for Spanish people in this paper (about 25 pg/person and day) are among the low values. similar to those estimated for adults in Japan (19 pg/person and day) [3] and for young people in the USSR (31 pg/person and day) [4] and they exceed the values obtained for Italien population (15, 10, 8.3, 13 .5 , 6.2 pgiperson and day) [5]. The value found is lower than the estimated one in Canada (45-55 pg/person and day) [6] and Hungary (100 pgiperson and day) [7].

Conclusions

The total intake value can be highly modified as a function of the diet composition, this one being deter- mined by several factors, such as dietary habits, economical and food availability, seasonal changes, fashions.

A value for the recommended cobalt intake has not been established, its requirements being related to those of vitamin B , 2 . which have been fixed by the WHO in 2 pg/person and day. The cobalt contribution by the diet exceeds the value corresponding to this amount of vitamin. For the mpment, it is not possible to establish a recommended daily cobalt intake until the role of this element in the organism is not totally knoh 11. though the usual diet does not seem to cause deficiencies.

References

[I] BARBERA, R . , R . FAR^ and R. MONTORO, J. Assoc. Off. Anal. Chem. 68 (1985) 511-513. [2] Balance Alimentario. Anuario de Estadistica Agraria. Ministcrio de Agricultura. Secretaria General

[3] YAMAGATA. N.. N. KURIOKA and T. SCHIMIZU, J . Raduat. Res. (Tokyo) 4 (1963) 8-15, [4] NODYA, P. I . . Gig. Sanit. 37 (1972) 108-109.

Tecnica. Espafia ( 1982).

Wissenxhaftlicher Kurzbericht 567

[5] Rossi, L. C., G . F. CLEMENE and G. P. SANTARONI, Rev. Environ. Health 3 (1978) 19-41. [6] KIRKPATRICK, D. C., and D. E. COFFIN, J . Inst. Can. Sci. Technol. Aliment 7 (1974) 56-58, [7] LINDNEK-SZOTYORI, K., and A. GERGELY, Nahrung 24 (1980) 829-837.

REYFS BARBERA and Dra. ROSAURA FAR&, University of Valencia, Faculty of Pharmacy, Department of Food Chemistry, Toxicology and Analytical Chemistry. Avda. Blasco Ibanez, 13. 46010 Valencia. Spain

Received September 23, 1985 Revised manuscript received November 27, 1985