ÁREAS DE AFECTACIÓN

107 children, representing 31.1% of all children, had pica. The majority of them (48.6%) had BPb of 10- < 25 mcg/dl followed by 31.8%

with BPb of 25- < 40 mcg/dl and 8.4% with BPb of 40- < 70 mcg/dl. p value is less than 0.001. This is shown in Table 18.

3.20 Relation of blood lead levels to the degree of anaemia in all the children in the study

Out of 159 children who had no anaemia (44.8% of all children), only 1.3% of them had BPb of 40- < 70 mcg/dl.

Children with severe anaemia were 32, representing 9% of all children in the study. No one of them had BPb of less than 10 mcg/dl. Most of them (46.9%) had BPb of 25- < 40 mcg/dl followed by 34.4% with BPb of 40- < 70 mcg/dl. Using chi square, p value approaches zero. Entering the data of haemoglobin as a dependent

variable and blood lead level as an independent variable, a positive correlation in a regression table is obtained. The correlation coefficient for this relation is r = 0.6.

These findings are shown in Figure 6.

CHAPTER FOUR

DISCUSSION

In this study, many discrepancies in the demographic features were observed between the three groups.

All children in the first group who are street children were above the age of five years and many of them were in the adolescent stage with obvious signs of puberty. This is well expected because children less than five years are not supposed to live an independent life away from parents or caregivers. Another reason is

that any trend for living independent life is not existent in smaller children and is expected to face vigorous resistance from families and society.

In many parts of Sudan, unfavourable socioeconomic factors such as war, famine, unemployment, and dislocation due to floods and drought lead to family disruption and forced children to fend for themselves leading to phenomena of street children and childhood labour.

It is realized also in this study that the group of street children were almost all males with the exception of three females. Although most of the children living in streets are males, the number of girls is on the increase because of war and dislocation.

The tribal distribution of children in the study reflects what has been mentioned above about the political, economic, and social changes that prevailed recently on our country. The group of street children was mostly from the southern and western parts of Sudan, which are foci of civil war, tribal tensions, and poverty

leading therefore to dislocation. Bannga in his study of social and health profile among street children in Khartoum had observed this.(29) The control group has an even tribal distribution most probably because Elfitehab is one of the ancient areas of Omdurman city in which certain tribes had inhabited since a long time. The paucity of eastern Sudan tribes in the three groups may reflect the overall distribution of Sudan population where the East is the least populated region.

Immunization status of street children is a matter of concern as most of them were either not immunized at all or partially immunized. This is attributed to the unfavourable living conditions of this group and the social background from which they came. Evidently, this could be a source of community health problems and an obstacle to the national health policy that should be looked for and remedied promptly. The high rate of immunization in the control group reflects the positive efforts of Ministry of Health and international health

organizations and the high level of health awareness of this population but still the small gap should be sealed. Nutritional supplements and adequacy is another issue for concern in street children as half of them do not feed well qualitatively and quantitatively but strangely enough, most of them seem to be well nourished. This may be due to inaccurate information delivered to the study team seeking for sympathy.

Regarding residence, most street children were homeless but the minority who lived in homes and were labeled as street children pose a question of what sort of family background that enforced them to street life.

Constipation was noted to be highly frequent among street children and to a lesser degree among children residing industrial areas. This either could be due to lead poisoning, as constipation is an early feature, or could be attributed to certain dietary habits and the type of food consumed.

Habits that predispose to lead poisoning were noted with increased frequency among children in the

study. Pica was noted in the group of children residing in industrial areas to be the most conspicuous factor contributing to high blood lead levels apart from being in such an environment. This is consistent with a study done on the impact of lead-contaminated soil on public health in USA. In this study, Charles X demonstrated a strong relation between elevated blood lead in children and the habit of pica in areas already contaminated by lead.(30) A considerable number of children in industrial areas group had low blood lead level and it may be concluded that living in an industrial area is not a hazard unless other factors contribute as vehicles for accessing the already presumed available lead in the environment. The most prominent example here is pica. Children with pica in all groups in the study were generally noted to have mild to moderate elevation of blood lead level. This had been observed by Gutelius MF et al on their nutritional studies of children with pica.(21)

Gasoline sniffing as a habit attained by street children is very prevalent among this group and it is the

single most important factor that put them in the unsafe range of blood lead level. A study done on gasoline sniffing and lead toxicity in Navajo adolescents showed that most of those adolescents were hospitalized for presumed lead intoxication and a considerable number of them presented first with toxic encephalopathy. Sniffing gasoline in that study was associated with poor school performance and abnormal behaviour.(28)

It has been noted that gasoline snuffers were also glue snuffers. This is an added predisposition to lead toxicity as glue also contains lead, though in a small amount. The combination of gasoline and glue sniffing and alcohol drinking in street children may be the probable explanation for the high rate of neurological symptoms and signs observed among this group rather than lead toxicity. If we compare the neurological findings in the three study groups, there is an escalation in their frequency related to the increase in blood lead level. So although glue, gasoline, and alcohol affect the CNS directly but still lead can explain or contribute to

such findings as convulsions, abnormal behaviour, abnormal gait, hearing and vision problems, abnormal speech, and hyperreflexia. This consistent with many studies done on the CNS effects of lead toxicity.(71,75,77) It is realized in this study that other physical findings detected in the children in the study were incidental, concomitant, resultant, or causative in relation to the theme of the study.

Poor hygiene was noted frequently among street children as well as skin infections notably scabies which usually outbreaks in closed poor unhygienic communities. Respiratory signs were noted relatively frequent among street children and children residing industrial areas. This could be explained by many factors. First, the unhygienic poor environment of both groups predisposes to acute and chronic respiratory infections. Secondly, the habit of glue and gasoline sniffing besides cigarette smoking in street children may cause chronic bronchitis and chemical pneumonitis. Thirdly, industrial fumes in industrial areas may contribute to attacks of

cough and wheezing in the nearby population. I have been told by doctors and pharmacists working in the vicinity of Khartoum and Omdurman industrial areas that the most frequent complaints of children in these areas are ARI and asthma or wheezing attacks and the most frequently prescribed drugs are antibiotics and bronchodilators.

According to the classification of Ateig(107), anaemia was noted evidently in the three groups notably among street children. Moderate and severe anaemias were slightly higher in street children compared to the control group. Apart from the strong correlation of BPb level to the degree of anaemia, other confounding factors may be nutritional micronutrient deficiencies especially iron and folate deficiencies. Salma HM in 1997 detected anaemia in 66.4% of 1252 schoolchildren.(108) In contrast to that study anaemia was detected in 76.3% of street children, 57% of children in industrial areas, and 49.6% of the control group.

Broadly looking at the relation of BPb level to haemoglobin level in this study, a positive correlation could be extracted. The anaemia of lead toxicity seems to be microcytic hypochromic as the prevalence of this peripheral blood picture is high among street children and children of industrial areas. The two groups had the highest BPb levels. The normocytic normochromic component had also a considerable frequency. This is consistent with studies done on the anaemia of lead poisoning.(62,63)

Blood lead levels in the three groups showed clearly that all street children had the highest BPb levels with varying degrees of severity but most of them were in the upper limits. Children residing in industrial areas were mostly in the mild to moderate BPb levels with considerable numbers in both the safest and the highest range. Children of the control group were mostly in the safe levels. Two key questions should be posed here. First, why some children in the group of industrial areas had very low BPb levels? Second question why some

children in the control group had BPb levels of mild to moderate range? The first question has answered earlier in this discussion and it has been concluded that being in an industrial area in Sudan is not by itself a hazard for lead poisoning unless associated factors contribute. A proven example of such a factor in this study is the habit of pica specifically geophagia (earth eating). Other factors probably may be closeness to a lead industry factory, father’s job linked to lead industry, and buildings surrounding the area.

The second question is the most important in this study. In other terms from where does the lead come to children in the control group? This is a frequently asked question by environmental investigators and doctors in countries with high rates of lead pollution. One possibility is that, lead comes from the soil in children with pica and from air in places near heavy traffic. Sousan B in a recent study in the year 2001 investigated lead pollution and other particulate matter from automobile emission in Khartoum and concluded that

there is a rise in the lead in air in certain heavy traffic places in Khartoum.(109) Gheis GA have noted this earlier in 1984 in a similar study.(110) There is a concern from the environmental people of the recently introduced small motor vehicle called Raksha that it is a source of lead pollution due to technical problems in its engine. There are more than twenty thousand Rakshas in Khartoum State and evidently, they could be a dangerous source of air pollution.

In this study, a positive relation between age and blood lead levels was found. This simply could be explained by the accumulative effect of lead. The longer the child is exposed to lead the higher is the blood lead level. This is noted specifically in street children.

Prevalence of lead poisoning in this study using the minimum accepted blood lead levels internationally, which is 10mcg/dl, was as follows:

All street children had elevated blood lead levels. Most of them (66.9%) had moderate to high levels.

84% of children in industrial areas had unacceptable blood lead levels. The children with moderate to high BPb levels were 31%.

Children in the control group had 48.2% in the safe level, 40.9% in the safe but unacceptable level, and 10.9% in the mild to moderate range of BPb.

Among street children prevalence of unacceptable social habits including gasoline and glue sniffing, cigarette smoking, and drinking alcohol is high. They have low level of immunization.

Children of industrial areas were comparable in most features to the control group apart from increased blood lead levels.

Blood lead increase with increased age. The younger the child the lower is the lead level and vice versa.

Pica was noted to be a strong positive factor for determining blood lead levels especially in children residing in industrial areas.

High blood lead levels were positively associated with many CNS complaints and constipation, abnormal behaviour, hearing problems, disturbance of gait, convulsions, and hyperreflexia.

Anaemia is prevalent among the three study groups. Haemoglobin levels were inversely related with BPb. The higher the lead the lower is the haemoglobin. The peripheral blood findings tend to be of the microcytic hypochromic picture with increased BPb with a considerable proportion of normocytic normochromic picture.

RECOMMENDATIONS

1. Screening of children and families at risk in Khartoum state. 2. Health education about the deleterious effects of lead should be

offered to risk populations and occupations.

3. Children with unexplained refractory anaemias, unexplained afebrile seizures, behavioural changes, unexplained encephalopathy, and mental retardation should be screened for lead poisoning.

4. Children with pica should be supplemented with enough iron and calcium, as this will decrease the susceptibility for lead poisoning.

5. Environmental surveys should be done to determine the sources of lead pollution in the community and efforts done to minimize them

6. Chelating drugs should be provided to solve the problems of those who are in need of Chelation therapy.

7. Provision of laboratory facilities for lead investigations at hospital levels and better facilities at central laboratories.

8. Some dangerous industries involving lead should be placed away from residential areas and health and environmental surveillance offered for the workers and their families.

9. Unleaded gasoline should be used in motor vehicles, as this will decrease air pollution by lead. There is a global agreement and a recommendation by WHO for this issue that should be implemented in our country.

10. Efforts should be guided by governmental and non- governmental organizations towards projects of primary health care services, counseling, and health education among street children.

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