NUCLEAR AND ISOTOPIC TECHNIQUES APPLIED TO NUTRITIONAL AND ENVIRONMENTAL PROJECTS SUPPORTED BY THE INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA) IN AFRICA

Mirinda-da-Cruz B*¹, Mokhtar N², Iyengar GV³ and B Smodis⁴

ABSTRACT

Nuclear and isotopes methods have been used in industrialized countries to enhance the sensitivity of nutrition and environmental monitoring techniques. The isotope techniques used in nutrition research are: (i) deuterium dilution to measure total body water (TBW) and body composition for evaluating nutritional status, to assess nutrient needs in dietary interventions and to perform impact analysis;(ii) deuterium elimination to measure breast milk intake to evaluate growth impact of weaning food interventions;(iii) double labelled water to measure energy expenditure for assessing the amount of dietary energy required and to identify whether an intervention changed the energy requirements;(iv) vitamin A studies using deuterium retinol or ¹³C-carotenoids for measuring total body vitamin A reserves;(v) ¹³C-amino acids and ¹⁵N labelling to measure the amount and rate of protein turnover in the body to find out the most efficient conversion of food to growth or maintenance of body protein stores; and (vi) the use of isotopic labels iron, zinc, calcium, magnesium, copper and selenium for nutrition monitoring. In conclusion, stable isotopes are invaluable since there is virtually no health risk involved when used correctly.

African countries are still struggling with many forms of malnutrition. The lack of efficacy and effectiveness of nutrition interventions is one of the factors that hamper the progress in eliminating malnutrition in Africa.

It is recognized that both supplementation and food fortification are effective means to correct nutritional deficiency of micronutrients particularly Fe depending upon the field conditions faced. Although significant progress seems to have been made to identify useful fortificants, the final outcome is dependent upon the type of supplement or fortificant used and the interactions between the nutrients involved as well as cost-effectiveness including the potential to reach large number of people. Nuclear and related isotopic techniques have been demonstrated as a unique tool to measure micronutrient bioavailability.

Applications of isotope techniques in nutritional sciences are progressing rapidly. The International Atomic Energy Agency (IAEA) has a mandate to promote the safe, secure and peaceful development of nuclear technologies. The use of isotopes or nuclear related techniques to evaluate human nutritional status and the nutritional quality of the foods is at the core of IAEA’s program in the human health area.
The objective of this review is to highlight the role of nuclear and isotopic techniques supported by IAEA to address several nutrition & environmental related projects in Africa.

French

Resumé
Les méthodes isotopiques et nucléaires ont été employées dans les pays industrialisés pour augmenter la sensibilité des techniques de mesure en nutrition et de contrôle de l'environnement.
Il existe plusieurs techniques isotopiques utilisées dans la recherche en nutrition comme: (i) la technique de dilution de deutérium pour mesurer l'eau totale de corps et la composition corporelle pour évaluer le statut nutritionnel etles besoins en éléments nutritifs dans des interventions diététiques aussi, pour faire l'analyse d'impact des stratégies nutritionnelles. (ii) la technique d’élimination de deutérium pour mesurer la quantité de lait maternel lors d’évaluation d'impact de startegienutritionnelle sur la croissance du bébé;(iii) la technique d’eau doublement marquée pour mesurer la dépense énergétique afin d’évaluer la quantité d'énergie nécessaire dans différentes conditions et sur différentes populations;(iv) la technique de mesure de la teneur corporelle en vitamine A en utilisant le rétinol marque au deuterium ou le ¹³C-retinyl palmitate;(v) Les acides aminés marqués au ¹³C et au ¹⁵N pour mesurer la quantité de protéine dans le corps ; et (vi) l'utilisation des isotopes stables de fer, zinc, calcium, magnésium, cuivre et sélénium pour les études de biodisponibilité et la surveillance nutritionnel.
Les isotopes stables sont de valeur inestimable puisqu'il n'y a pratiquement aucun risque sanitaire impliqué s’ils sont utilisés correctement.
Les pays africains luttent toujours contre plusieurs de formes de malnutrition. Le manque d'efficacité et d’impact des interventions en nutrition est l'un des facteurs qui entravent le progrès dans l’élimination de la malnutrition en Afrique.
Il est reconnu maintenant que la supplémentation et la fortification alimentaire sont des moyens efficaces pour corriger l'insuffisance en micronutriments en particulier en fer. Bien que beaucoup de progrès semble avoir été accompli dans ce domaine, les résultats dépendent du type de suppléments ou de fortifiants utilisés et de la biodisponibilité des nutriments impliqués. Les techniques isotopiques nucléaires ont été désignées comme outil de choix pour les études de disponibilité des micronutrients.
L'agence internationale de l'énergie atomique (l'AIEA) favorise l’utilisation de la technologies nucléaires a des fins de paix et de développement. L'utilisation des isotopiques et nucléaires pour combattre la malnutrition est incluse dans le programme de la santé humaine de l'IAEA.
L'objectif de cette revue est de décrire l’utilisation des techniques nucléaires et isotopiques dans les études nutritionnelles et de souligner les activités de l’AIEA dans ce domaine en Afrique.

INTRODUCTION

Global nutrition problems (hunger, malnutrition, intrauterine growth retardation, mineral deficiencies, obesity, cancer and osteoporosis among others) are responsible for millions of deaths in developing and developed countries. According to the United Nations sub-Committee on Nutrition [1], the international community has the following global challenges at the beginning of this millennium: 170 million children <5 years are malnourished, 1.5 billion people are affected by iron deficiency anaemia, 740 million people suffer from goitre, 230 million children are afflicted with subclinical vitamin A deficiency. The worst conditions continue to be, largely, in Africa. One out of every three people in sub-Sahara Africa is undernourished.

The major nutrition problems facing Africa include protein energy malnutrition and deficiencies of key micronutrients such as iron, iodine, and vitamin A; diet-related non-communicable diseases, and HIV/AIDS. In addition, three hundred million Africans, nearly half the region's population, still live in extreme poverty. The spread of HIV/AIDS threatens to wipe out important gains in life expectancy. The prevalence of underweight preschool children in both Western and Eastern Africa was about 36% in 2000, countries from this region are experiencing a rise in underweight (30% in 1990) [1]. Estimates show that over 85 million people living in Africa are iodine deficient, 80% of women, infants and young children suffer from anemia and vitamin A is a public health problem in 64 African countries [2]. The 2002 World Health Report [3] confirms that at least 30% of all “disease burden” measured in disability-adjusted life years (DALYs) occurring in sub-Saharan Africa, is due to underweight, HIV/AIDS, micronutrient deficiencies and water sanitation.

Preventing malnutrition in many of the African countries can save thirty percent of infant and child deaths and twenty percent of maternal mortality. Moreover, seventy percent of all illnesses related to common infections can be prevented through improved nutrition alone. Indeed, investments in nutritional programs have been shown to be an effective way to improve child survival, poverty alleviation and sustainable development. In Africa, progress has been made in reducing the absolute number of hungry people. However, meeting the UN Millennium Development Goals by 2015 of reducing hunger by half raises difficult challenges in many African countries [4].

Nutrition problems are inevitably linked with elevated environmental pollution. Many harmful substances including toxic heavy elements are released, due to anthropogenic activities such as agriculture and industry, into the air, water and soil. Afterwards they can be easily taken up by biosphere thus contaminating food consumed by humans. Once accumulated in the body they may cause serious deleterious effects on human health. Therefore, studies for identifying critical pollutants in contaminated and the role of toxic elements in human populations areas are needed.

In seeking solutions to these problems, increasing farm productivity, supplementation targeted to high-risk groups combined or not with program of food fortification and dietary diversification strategies are the main intervention used to tackle micronutrient malnutrition in developing countries. However, early impact evaluations of these interventions indicate a low rate of progress in micronutrient malnutrition control among African nations [5].

Many types of constraints have interfered with the success of nutrition and /or environmental interventions in Africa; the most important are political, socio-economic and technical.

The objective of this review is to highlight from IAEA’s perspective “the role of nuclear and isotopic techniques in evaluating and monitoring nutrition and environmental interventions in Africa and to address some technical issues.

NUCLEAR AND ISOTOPIC TECHNIQUES IN HUMAN NUTRITION AND RELATED ENVIRONMENTAL STUDIES

Applications of isotope techniques in nutritional sciences are progressing very rapidly in key areas of nutrition and health: assessment of nutritional status, nutrient requirements, and micronutrient malnutrition; detection of infections; analysis of foods; and air pollution measurements.

The International Atomic Energy Agency (IAEA's) main objective is to promote the safe, secure and peaceful development of nuclear technologies. The use of isotopes or nuclear related techniques to evaluate human nutritional status and the nutritional quality of the foods is within the IAEA’s program in the human health area [6]. The IAEA’s activities in nutritional evaluation include use of isotope technique for assessment of human body composition, nutrient intake, and vitamin and mineral availability in developing countries [7].

Mainly the focus of isotopic techniques is on measurements of breast-milk intake, energy expenditure, micro/macronutrient status/bioavailability and body composition. The stable isotope techniques, although still costly, can be used effectively by food industry for developing nutrient-fortified food products, by governmental and international institutions for designing food fortification programs and public health authorities for establishing reliable dietary recommendations for intake of inorganic nutrients [8].

There are two forms of isotopic tracers: radioactive and stable. Radioactive isotopes can be detected via their radiation. They have many important applications, such as measurements of body composition, uptake and bioavailability of micronutrients and urea breath test to examine bacterial colonization by Helicobacter pylori. However, the risk of radiation related health effects has overtime dampened the use of radiotracers in human subjects. Stable isotopes on the other hand are invaluable since there is virtually no health risk involved in their use. They are, therefore, preferred for work in humans, especially in infants and pregnant women. Many naturally occurring elements exist as a mixture of two or more stable non-radioactive isotopic forms. There are heavy stable isotopes (eg ⁵⁴Fe, ⁵⁶Fe, ⁵⁷Fe, ⁵⁸Fe, ⁶⁴Zn, ⁶⁶Zn, ⁶⁸Zn, ⁷⁰Zn) and light stable isotopes (eg ¹H, ²H, ¹³C, ¹²C, ¹⁵N, ¹⁴N, ¹⁶O, ¹⁷O, ¹⁸O) [9].The main advantages and disadvantages of these two forms of isotopic tracers are summarized in the Table 1 from references [10,11,12,13].

The stable isotopes can be administered either orally (water, food, etc) or intravenously. Depending on the rate of absorption of the administered compound, the stable isotopes will be incorporated into metabolic products, such as body water, urea or CO₂. These can be sampled in saliva, milk, breath, urine, and stool. The ratio of minor to major isotopes can then be determined by isotope ratio mass spectroscopy, infrared absorption or emission spectroscopy [9]. Nuclear techniques used in all stages of human life are summarized in Table 2.

CONTRIBUTION FROM IAEA TO NUTRITION AND RELATED ENVIRONMENTAL STUDIES

The International Atomic Energy Agency (IAEA) is contributing to alleviation malnutrition through strengthening the application of isotopic and nuclear related techniques in human nutrition [7,9,14] by offering technical solutions to improve monitoring techniques and identifying effective strategies in nutrition intervention programs. There are several programs within the IAEA, like Coordinated Research Projects (CRP), Thematic Co-ordinated Research Projects (TCRP), and Technical Cooperation Projects (TCP).

A Coordinated Research Project (CRP) is a mechanism to which group of countries are brought together to work on a well-defined research topic, and the mean duration of a CRP is 3 years. A modest annual funding to developing countries is made available by the IAEA mainly for sample collection, analysis, and supplies. Collaboration between scientists from developing and industrialized countries is stimulated and exchanges of information are encouraged through participation in research coordination meetings (RCMs).

Recently, a new type of CRP has been introduced that is dedicated for supporting PhD students. Thematic Co-ordinated Research Projects or Capacity Building CRP (T-CRP) is a new program increasing the scope of a normal CRP for capacity building in developing countries. Pairs of countries (developed and developing countries) are stimulated to work together. T-CRP is promoting a postgraduate training in the country of origin with a possibility of training in developed country. It will have a longer duration up to 4-5 years.

TCPs (Technical cooperation projects) are substantially large national projects contributing to socioeconomic development of a given Member State. They are programmed for 2-4 years, and if on a regional basis, they are called regional projects with multiple participating countries. The TC Projects in Nutrition should have a strong Government support of National Nutrition Programs. The main objective is transfer of mature nuclear and related techniques for a specific problem at the same time building up scientific and technical capacity in the country. The implementation strategy for TC projects has to consider several criteria for approval. There has to be a nutrition intervention or health-related problem in need of evaluation. There must be direct links between TC counterparts and the public health stakeholders that can absorb the recommendations resulting from the project and use them to modify interventions if needed. One of the advantages of nuclear techniques over conventional methodology of evaluation is the response time in the impact evaluation and the number of subjects required. With this, the use of nuclear techniques can increase the efficiency of the evaluation of such programs. In nutrition interventions a multidisciplinary approach is required; a partnership with public and/or private sectors is important for a successful evaluation of the program. IAEA supports infrastructure (equipment and supplies), workshops, subcontracts, experts, fellowships and scientific visits.

Some examples of human nutrition and related environmental studies within the IAEA Nutrition Program [9] based on stable isotopes methodology are:

1. Estimation of total energy expenditure to determine the caloric expenditure of people in their normal environment. It is accurate and can be applied under field conditions. After administration of a simple dose of doubly labeled water, ²H₂¹⁸O, both isotopes equilibrate with total body water and are eliminated differentially in body fluids over a period of days. Deuterium (²H) leaves the body as water and ¹⁸O leaves it as water and CO². Thus, the difference the rate of loss of the two isotopes (¹⁸O and ²H) is used to calculate CO₂ production of the subject, which in turn is used to calculate energy expenditure.

This isotopic technology is very accurate and thus the FAO/WHO/UNU expert committee convened during 2001 to establish new energy recommendations is using the results of investigations on energy expenditure of young children in Cuba. Prior to this project no data existed from Latin America to provide a scientific basis to formulate food programs suited to the local conditions. Moreover, the data from the Cuba study indicates that the existing values overestimate energy needs in children below 7 years old [15]. This could be a good opportunity for African countries to follow the Latin America experience and start setting up their own energy recommendations.

2. Lean Body Mass (Body Composition)
A trace dose of water labeled with ²H or ¹⁸O is administered and allowed to equilibrate for 4-6 hours. Isotope enrichment in urine or saliva samples is measured to calculate body water volume. Total body water is used to quantify fat-free mass. Body composition is calculated from measured body water and the hydration coefficient of fat-free mass. The amount of fat (adipose) tissue is calculated as the difference between total body weight and fat-free mass (lean body mass). An increasing problem with obesity exists in countries considered to be in “nutrition transition”. As a result from the project in Chile, it was recognised that it is necessary to reduce of the energy intake of children in order to prevent obesity [16]. On the other hand, lean body mass can be considered a valuable indicator to monitor body wasting in HIV/AIDS patient, which shows a decrease in lean body mass and an increase in energy expenditure and protein catabolism when compared to HIV negative subjects. In the recently launched IAEA Regional Africa Project involving 9 countries, isotopes will be used to assess the efficiency of food-based approaches to improve nutritional status of people living with HIV/AIDS (PLWHA). The pilot study will start in Uganda and Senegal.

3. Breast Milk Intake
The mother is given a dose of ²H- or ¹⁸O-labeled water, which mixes with the body water pool and is transferred to the baby via the breast milk. By collecting samples of the mother’s saliva or milk and the baby’s saliva or urine, the breast milk intake of the baby can be calculated. For example, the IAEA gave technical support to a community nutrition program in Senegal. The results indicated that breast milk output was not influenced by supplementation. In contrast, the lactose, total protein and zinc contents of milk increased significantly in supplemented mothers [17]. The Agency’s counterpart in Ghana has used the same technique to assess the impact of food supplement on nutritional status of lactating mothers and their infants. Results have shown that babies’ growth from supplemented mothers was significantly higher than those from non-supplemented mothers. The Ghana government will use the results to strengthen its ongoing food supplementation program.

4.Trace Element Bioavailability
The uptake and metabolism of labeled micronutrients can be traced in-vivo. In fact, stable isotopes techniques provide the most reliable way of measuring the uptake and bioavailability of trace elements in humans. As a result of the IAEA’s activities in Chile the government modified its policy for pre-school children nutrition intervention programs (coverage of ~1.3 million). The study had shown that anaemia was reduced from 28.8% to less than 8.8% within a year after using foods fortified in iron and zinc in a sample of 300 children [9]. This techniques can be used to determine the effectiveness of fortification and supplementation programs in several developing countries and could be useful to assess the success of new programs in Africa (see table 3).

5.Analysis of Foods
Neutron Activation Analysis (NAA) is very effective technique due to its exceptional sensitivity for several trace elements. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) also offers multi-element determinations. The application of NAA-related methods is particularly attractive for developing countries since many research reactors are available to provide the needed neutron source. In Libya, for example, under an IAEA project this nuclear method is used to determine food nutritional values and dietary intake of minor and trace elements [9].

6.Osteoporosis
Low energy x-rays are passed through the bones to measure the mineral (calcium) content of the bones using DEXA (Dual Energy X-ray Absorptiometry). The precision of DEXA is very high and the data can be standardised for age, weight, height and ethnic status.
A recent CRP has examined global variations in bone mineral density of young adults in nine countries. A total of 6207 subjects were recruited. Approximately 12-20% of the global variation in bone mineral density is due to anthropometric differences and the country of origin accounts for 4-10%. Significant differences were found in bone mass that, if persisting into old age, may contribute to 2-3 fold difference in fracture risk [18].

7. Detection of Infection

The ¹³C-urea breath test is used to detect Helicobacter pylori infection in humans. Breath is collected for a base value before a ¹³C-labeled urea is administered. The enzyme urease of H. pylori breaks down the urea into ammonium and labeled bicarbonate. The latter compound will be metabolised by the person into carbon dioxide and expired. After 20-30 minutes a second breath sample is collected and measured for the label.
A CRP on H. pylori infection in children revealed infection rates of 86% in Senegal and 87% in Benin. In Indonesia, 58-67% of malnourished children tested positive for H. pylori, while 33% of the well-nourished children were infected [9].

IAEA-SUPPORTED NUTRITION AND RELATED ENVIRONMENTAL STUDIES IN AFRICA

Resources spent by IAEA :
African investigators have not been very active as participants of the IAEA projects in Nutrition and Health-Related Environmental Studies. The total amount of contributions to the African continent (Not all 54 countries, including 48 in Sub-Saharan Africa and 6 in North Africa are members of IAEA) by the Nutritional and Health-Related Environmental Studies Section at IAEA in the last 15-20 years is in the order of US$ 400,000.00 for CRPs and US$ 2,000,000.00 for TCs projects. Please refer to Tables 4, 5 and 6.

Some examples of African participation in running CRPs:
A CRP on “application of nuclear techniques in the prevention of degenerative diseases (obesity, non-insulin dependent diabetes and coronary heart diseases) in ageing” has only one country from Africa: Nigeria. A one year follow-up of lean cohort (BMI 21-22 kg>m²) in Nigeria has shown: (i) increase in body weight and BMI (ii) increased body fat (iii) increased prevalence of obesity and (iv) increased level of fasting insulin and insulin-glucose ratio. The conclusions are that the population is yet to reach the BMI threshold above which worsening of glycaemia status accompanies the increases in weight gain. [19,20]

Benin and Senegal are participants in the CRP on “the use of isotopes techniques to examine the significance of Helicobacter pylori infection and malnutrition”. The prevalence of this infection in children was measured successfully by the ¹³C urea breath test. Measuring anthropometric growth and decrease of infection will be assessed by further investigations using antibiotics and probiotics donated from Belgium.

Kenya and Morocco are participants in a recently launched CRP on “application of isotopic and nuclear techniques in the study of nutrition-pollution interactions and their impact on the nutritional status of human subjects in developing country populations”. The objective of the research study in Kenya will be to assess the effect of pollutants eg lead and cadmium on nutritional status of pregnant women and new-born babies in polluted areas, and the objective of the research study of Morocco will be to evaluate the degree of pollution of ground water in industrial areas and its effect on nutritional status in school children [21]

Ghana is participating in a new T-CRP on “isotopic and complementary tools for the study of micronutrient status and interaction in developing country populations exposed to multiple nutritional deficiencies” in collaboration with WHO to investigate “Evaluation of vitamin A pool in post partum women supplemented with vitamin A, using carbon isotopes”.

Kenya and South Africa participated in the CRP on workplace air pollution monitoring aimed at linking results of chemical analyses with pulmonary and other diseases found in exposed workers. The participants were analysing airborne particulate matter at workplaces and biological materials such as hair, nails, urine and blood, to assess biological exposure.

Ghana has been participating in the CRP on “Validation of plants as biomonitors of trace element atmospheric pollution”. In the study, the levels of toxic element pollution as obtained by analyses of local lichen species are being assessed in gold-mining and other industrial areas situated in the moist evergreen and semi-deciduous forests in Ghana.

Within the framework of a CRP on “Health impacts of mercury cycling in contaminated environments”, the Tanzanian participant is investigating exposure levels to mercury in the Lake Victoria gold fields. The recovery of gold in the area involves the use of mercury amalgamation because it is easy, cheap, and does not require sophisticated tools. The gold-mercury amalgam is placed in a firing pot or retort and fired to evaporate mercury and leave behind gold. In this way, highly toxic mercury enters the environment and potentially contaminates food.

Recently a new CRP on the “Use of nuclear and related analytical techniques in studying human exposure to toxic elements consumed through foodstuffs contaminated by industrial activities” has been started. It aims at determining the extent to which toxic element levels in food are affected by surrounding industrial activities and to assess potential human exposure from the consumption of such foodstuffs. Two African countries participate in this collaborative research: Ghana and Nigeria

Selected Technical Cooperation Projects-TCPs in Africa:
The most successful TCP in Africa is on “Isotope aided evaluation of community program” in Senegal. The TCP in Senegal provided the local authorities with irrefutable scientific evidence that is needed to assess its community nutrition program. The isotopic methods are being used to measure how much breast milk the baby is taking, the nutrients that are being transferred and the body composition of both mother and baby. It can indicate the best time during pregnancy at which to provide supplement to the baby that is being weaned, and the value of weaning foods to be added to their diets.

The project in Senegal was aimed to evaluate the food supplementary program (Community Nutrition Program (CNP) launched by the Senegalese Government in order to protect the most vulnerable groups (women and children) in poor urban areas of Senegal. The study has shown, using isotopic and related techniques, that the supplemented food has significantly influenced the quality of the breast-milk (increased concentrations of lactose, protein and Zn). As a consequence, growth of the babies at 3 months was significantly above normal. The results also suggest probable improved levels of fat-soluble vitamins, particularly vitamin A.

These results have been presented to the National Commission for Combating Malnutrition of the Senegalese Government and have been used to refine the forthcoming Senegalese Nutrition Program (PRS). The PRS is a major national nutrition initiative planned for a period of 10 years (2002-2012), resulted from the impact of the CNP.

The TCP on “Breast milk trace-element composition and infant growth” in Ghana is completed. The objective was to evaluate a nationwide food supplementation program (SFP) targeting lactating women and their infants using isotope and related techniques. The project was implemented in collaboration with the Nutrition Unit, Ministry of Health, headed by the National Coordinator of the National Supplementary Feeding & Education Program (NSFEP). The results from this project is being used for an overall review of the national nutrition intervention.

The TCP on “Food analysis and routine monitoring of aerosols and drinking water sources” in Libya is aimed at establishing a national capability for the determination of food nutritional values and dietary intake of minor and trace elements, and for routine monitoring of aerosols and drinking water sources.

The objective of the TCP project on “The effect of air and water pollution on public health” is to increase the country’s capability for monitoring and control of air and water pollution levels with the aim to prevent cancer and respiratory diseases in Madagascar.

In Nigeria the TCP project on “Trace element methods for studies: Workplace monitoring” is being implemented. The counterparts are strengthening the national capability for monitoring occupational exposure of workers to selected air pollutants and assessing the health hazards associated with various levels of exposure.
Some projects ended before its implementation due to external factors like the TC “Evaluation of supplementary infant feeding practices in Ethiopia” which had failed because of lack of government support to start the program and the TC “Use of isotopes in investigating micronutrient deficiencies” in Sierra Leone which had failed because of the country’s war.

FUTURE INITIATIVES

Africa is facing several challenges to overcome the need for eliminating malnutrition, especially in women and children. One-way of doing it is by introduction of multiple or single supplementation/fortification programs of a potential nutrient or diet interactions in the target population. Several African countries do have such programs but the challenge is their evaluation, sustainability and effectiveness. Nuclear and isotopic techniques are valuable tools in helping to meet the nutritional challenges. It seems there is a lack of awareness of the IAEA activity in Nutrition by the African governments. Hence it is recommended that the IAEA avenue be utilised effectively.

There are several future opportunities for the African countries to strengthen capacity building and participating in future IAEA CRPs. Some examples foreseen CRPs (2003-2004): 1. CRP on nutritional and other factors contributing to IUGR (intra-uterine growth restriction); 2. CRP on increasing obesity in developing countries and its implication on public health; 3. CRP on Calcium metabolism in osteoporosis in the elderly; 4. Regional project on HIV/AIDS and nutrition using body composition measurements; and 5. CRP on assessing exposure to toxic elements using the placenta as a biomarker.

Similarly, for the next TC cycle 2005-2006, the time is ripe for the African Countries to submit new projects through their Atomic Energy Authorities to be submitted to the Agency by the end of this year 2003.

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All authors are affiliated with the International Atomic Energy Agency - IAEA, A-1400 Vienna, Austria.
*¹Corresponding author, Nutrition Technical Officer, Email: B.Miranda-da-Cruz@iaea.org
²Nutrition Technical Officer, Email: N.Mokhtar@iaea.org
³Head Nutritional and Health-Related Environmental Studies Section, Email: G.V.Iyengar@iaea.org
⁴Environment Technical Officer, Email: B.Smodis@iaea.org