1. By Dr. Muawia Eltayeb Ahmed Pr. Zein Karrar
BLOOD LEAD LEVELS AND LEAD TOXICITY IN HIGH-RISK GROUPS OF SUDANESE CHILDREN By
Dr. Muawia Eltayeb Ahmed
Pr. Zein Karrar

2. INTRODUCTION
Lead is the commonest of the heavy metals: 13mg/Kg of the earth’s crust
Extremely toxic___ not natural constituent of the human body
Popular in industry
Sources: found naturally in soil, water, and air
Most abundant contaminating sources are: paints and gasoline

3. Industries: car batteries solder alloys and cable sheathings
Pigments and colours
Rust inhibitors
Ammunition
Plastic stabilizers
Glazes in cookware
Insecticides, pesticides, and rodenticides
Plumbing fittings and lead pipes in water systems

4. Some folk medicines and cosmetics e.g. Alkohl
Toys, curtain weights, and clothing accessories ingested by children with pica
Placental transfer and breast milk in mothers with high lead burden

5. ROUTES OF EXPOSURE
Inhalation: motor vehicle exhaust and gasoline sniffing practiced by street children in Sudan and some adolescent ins many parts of the world
Ingestion: from water transmitted in lead pipes, food canned or cooked in lead glazed cookware, or children with pica
Direct contact: traditional medications for skin or eyes__ pellets retained in the body

6. POPULATIONS AT RISK Preschool-age children
Nutritional deficiencies of iron and calcium
Children with habits like pica and gasoline sniffing
2-3 years
Children whose parents’ occupation involve lead
Close residence to industrial areas

7. EPIDEMIOLOGY AAP statement in 1987:
(Lead levels > 25mcg/dl are unacceptable for children)
Impairment of cognitive function occurs at levels > 10mcg/dl
In Western hemisphere decline due to elimination and screening
In Sudan only environmental studies

8. CLINCAL PICTURE Nonspecific Recurrent symptomatic episodes
Irritability, anorexia, decreased play activity
Lead colic: sporadic vomiting, intermittent abdominal pain, constipation, loss of developmental skills, anaemia
Encephalopathy: persistent vomiting, ataxia, impaired consciousness, coma, seizures

9. CLINICAL PICTURE
Subtle effects: neurobehavioural and cognitive performance
IQ deficits, behavioural disorders, hearing defects, slowed growth
For every 10mcg/dl increase in BPb there is a decrease of 4-7 points in mean IQ
Children with high BPb are 7 times more likely not to graduate from school, 6 times more likely to have reading difficulties

10. CLINICAL PICTURE Renal: chronic nephropathy, Fanconi syndrome
Impaired vit D and calcium metabolism
Neuro-psychiatric disturbances
Preterm delivery, LBW
Lead poisoning should be suspected in: mental retardation, behavioural changes, recurrent abdominal pain, unexplained refractory anaemias, persistent vomiting, uncontrolled seizures

11. LABORATORY DIAGNOSIS Blood lead level Microcytic anaemia
Basophilic stippling of erythrocytes
 erythrocyte protoporphyrin
 urinary coproporphyrin
Lead lines on radiology
Radiopaque flecks on abdominal radiograph

12. BPb and recommended treatment
Environ intervention
Aggressive environ intervention
Chelation therapy
Medical emergency and aggressive therapy
< 25mcg/dl
25- 45mcg/dl
mcg/dl
> 70mcg/dl

13. JUSTIFICATION No study in Sudan
Recent trend of urbanization and industrialization besides discovery of petroleum→ an era of environmental health problems
The need for workers on the health and environment field to increase awareness of the clinical and environmental impact of lead poisoning

14. OBJECTIVES The purpose of this study is to:
determine blood lead levels and prevalence of lead poisoning in two high-risk groups: street children and children residing in industrial areas
compare the findings to a non-risk control group
assess the clinical and other laboratory findings and correlation to BPb

15. OBJECTIVES
4. Relate the findings to demographic variables, family background, abnormal habits, nutritional state, and common childhood illnesses

16. MATERIAL AND METHODS
Cross-sectional community-based comparative study April to July 2001
Study populations and areas:
Study group 1: street children from their gathering places in many parts of Khartoum
Study group 2: children in industrial areas of Khartoum North, Omdurman, and Khartoum
Control group: children from Elfitehab and Salha village south of Omdurman

17. 355 children were studied:118 for group 1, 100 for group 2, and 137 for the control group
Cluster sampling was used for houses or gathering places and simple random sampling for the study units
A structured questionnaire was used to record clinical findings
Investigations: BPb level, Hb, peripheral blood picture

18. Consent
Official authorities permission
Counseling and advice
Inclusion
Exclusion
Data analysis

19. RESULTS Street children were almost all males (3 females out of 118)
111 street children (94.1%) sniff gasoline and 96 (81.4%) sniff glue
40 children (40%) residing in industrial areas had pica or a history of pica, while 52 children of the control group (38.2%) had this habit

20. RESULTS Blood lead levels
BPb mcg/dl
Group 1
Group 2
Control
No. %
< 10 16 66
48.2
10-<25 39
33.1 53 56
40.9
25-<40
44.9 23 15
10.9
40-<70 26 22 8
>70
Total
118
100
137

21. RESULTS BPb in mcg/dl Age groups in years <1 1-<5 5-<10
10-<15
>15
No. %
<10 13
76.5 26
29.9 27
21.3 15
14.6 1
4.8
10-<25 4
23.5 50
57.5 55
43.3 34 33 5
23.8
25-<40 9
10.3 38 35
42.9
40-<70 2
2.3 7
5.5 19
18.4 6
28.6
total 17 87
24.5
127
35.8
103 29 21
5.9

22. Relation of BPb to age groups

23. Relation of BPb to bowel habits
mcg/dl
Normal
Diarrhoea
Constipation
No. %
<10 70
32.7 10
31.3 2
1.9
10-<25
105
49.1 11
34.4 29
27.6
25-<40 34
15.9 8 25 48
45.7
40-<70 5
2.3 3
9.4 26
24.8
Total
214 61 32
9.1
29.9

24. Relation of BPb to convulsions
Mcg/dl
Convulsions
No convulsions
no. %
No.
<10 82
23.8
10-<25 2
18.2
146
42.4
25-<40 4
36.4 87
25.3
40-<70 5
45.5 29
8.4
Total 11
3.1
344
96.6

25. Relation of BPb to pica BPb mcg/dl Children with pica No pica No. %
<10 12
11.2 68
28.7
10-<25 52
48.6 89
37.6
25-<40 34
31.8 55
23.2
40-<70 9
8.4 25
10.5
Total
107
31.1
237
68.9

26. Relation of BPb to behaviour
mcg/dl
Abnormal behaviour
Normal behaviour
No. %
<10 82
27.2
10-<25 6
11.1
142
47.2
25-<40 23
42.6 68
22.6
40-<70 25
46.3 9 3
Total 54
15.2
301
84.8

27. Relation of BPb to the degree of anemia

28. CONCLUSION
Prevalence of lead poisoning using the minimum accepted level is as follows:
All street children are lead poisoned- 66.9% had moderate to high levels
84% of children in industrial areas had levels >10mcg/dl, 31% had moderate to high levels
48.2% of the control group had safe levels, 40.9% in the safe but unacceptable level,

29. CONCLUSION and 10.9% had mild to moderate levels
BPb increases with age
Pica is a strong positive determining factor for BPb level
 BPb levels were positively associated with many CNS complaints, constipation, abnormal behaviour, and convulsions

30. CONCLUSION Anaemia is prevalent in the three groups
Haemoglobin levels were inversely related to BPb
Peripheral blood picture findings tend to be microcytic hypochromic with increased lead with a considerable proportion of normocytic normochromic picture

31. RECOMMENDATIONS Screening of children and families at risk
Health education offered to risk populations and occupations
Screening offered for children with refractory anaemias, difficult to control seizures, behavioural changes, unexplained encephalopathy, and mental retardation
Children with pica supplemented with iron and calcium

32. RECOMMENDATIONS Environmental surveys
Industrial facilities should be placed away from residential areas
Use of unleaded gasoline
Provision of better lab facilities and drugs

33. THANKS
DR. MEA IDRIS