DAMPAK KESEHATAN PENCEMARAN UDARA

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					The Effect of Calcium-Supplementation on Reducing
     Blood-Lead Levels Among School Children
               in Bandung, Indonesia




                      Budi Haryanto
           DEPARTMENT OF ENVIRONMENTAL HEALTH
                 UNIVERSITY OF INDONESIA
DAILY TRAFFIC
          BACKGROUND
Plumbum (Pb) is generally still being
  used as a gasoline additive to increase
  octane in Indonesia up to 2006
Effects of Pb on human include brain
  damage, nerve system, kidney, bone
  marrows, and other organic system of
  children
Several studies on BLLs in Indonesia
  indicated that high risk of health on
  the target group of the studies
          BACKGROUND
Calcium has effect on the Pb absorption
 in human body and able to provide
 protection against Pb exposures
There is a scientific need of proving the
 effect of Calcium supplementation
 among children able to protect Pb
 absorption from environment and to
 make decision makers aware on the
 reduction of Pb in environment control
Lead Free Gasoline Worldwide
            2004




                         Lead Free
                         Leaded
              OBJECTIVE
To identify the effects of calcium
  supplementation on reducing blood lead
  levels of school children in Bandung,
  Indonesia:
  to examine daily calcium supplementation
  for three months could reduce blood lead
  levels larger among those children who
  consumed 500 mg vs. 250 mg
  to determine factors that contributed to the
  reduction in blood lead with calcium
  consumption
          STUDY DESIGN
A randomized community trial design among
  elementary schools children in Bandung,
  Indonesia between August 2005 and
  December 2006.
A total of 400 school-children 3rd and 4th
  graders (9 and 11 years old) were
  enrolled from 40 schools, randomized to
  one of three intervention groups (500 mg
  Ca/day; 250 mg Ca/day; no supplement)
  and followed for three months between
  June and December 2006
        STUDY DESIGN
336 students from 35 schools
 completed the intervention phase of
 the study. Of those, 298 participants
 had complete data on blood lead
 levels before and after the
 intervention and are included in the
 analyses
                     STUDY DESIGN
The description of each group and its intervention is shown in the following contexts:

       O1      X1     O2      (N=103)
       O3      X2     O4      (N=93)
       O5             O6      (N=102)


O1 = Pre-BLLs of Elementary School Children
X1 = Intervention Ca supplement of 500 mg/day for 3 months
O2 = BLLs of Elementary school children after consuming Ca supplement of 500 mg/day
O3 = Pre-BLLs of Elementary School Children
X2 = Intervention Ca supplement of 250 mg/day for 3 months
O4 = BLLs of Elementary School children after consuming Ca supplement of 250 mg/day
O5 = Pre-BLLs of Elementary School children
O6 = BLLs of Elementary School children after 3 months
Mayor of Bandung City
 and Wife, May 2005
Minister of Environment
       May 2005
INTERVIEW
ANTHROPOMETRIC
LEADCARE
 COMPARISON CHILDREN BLLs
STUDIES IN JAKARTA 2001 & 2005
                  2001            2005
               CDC-USAEP    UI-JICA-USAEP

BLLs average    8,6 μg/dl      4,2 μg/dl


% BLLs >= 10     35 %           1,3 %
μg/dl
                        Association between Pb-air and Pb-blood in
                               Jakarta-Serpong 2004-2005

                 0.14                                                          10
                                                                    Pb-Air
                                                                               9
                 0.12                                               Pb-blood
                                                                               8
                 0.10                                                          7
Pb-air (ug/m3)




                                                                                    Pb-blood
                                                                               6




                                                                                     (ug/dl)
                 0.08
                                                                               5
                 0.06
                                                                               4

                 0.04                                                          3

                                                                               2
                 0.02
                                                                               1
                 0.00                                                          0
                          EMC     Trisakti      HI      Lbk Bulus    Kr Jati

                                             Location
                                                 Intervention Group (%)
                 Characteristics          Without Ca      250 mg      500 mg     p*
Characteristic   of participants          (n = 102)      (n = 93)    (n = 103)
                 Sex
demographic       Male                        42.3          36.9       49.3      0.04
                  Female                      57.7          63.1       50.7
                 Transport to school
                  Walk                        70.8          44.6       51.0      0.43
                  Bike                         0.0           0.0       11.0
                  Motorbike                   11.5          34.7       14.0
                  Car/public transport        17.7          20.7       24.0
                 Distance to school
                  < 200 m                     26.0          11.9       19.8      0.01
                  200 – 500 m                 38.5          31.7       29.7
                  501 – 1000 m                20.8          25.7       16.8
                  > 1 km                      14.7          30.7       33.7
                 Duration to school
                  < 5 minute                  28.1           9.8       24.8      0.06
                  5 – 15 minute               44.8          73.5       48.5
                  16 – 30 minute              18.8          13.7       18.8
                 > 30 minute                  8.3            3.0        7.9
                 Home location
                  Main road                    8.6          12.7        8.1      0.90
                  Cluster housing             17.2          22.6       36.4
                  Kampong/Slum area           74.2          64.7       55.5
                 Nutritional status
                  Over                         2,0           0.0        0.0      0.03
                  Normal                      72,7          88.0       91.7
                  Under                       25,3          12.0        8.3
                 Hemoglobin
                  <12 g/dl                    4.62           2.86       5.38     0.75
                  ≥12 g/dl                   95.38          97.14      94.62

                    * p value of ordered logit regression
 Difference in blood lead levels
  before and after intervention
                              Blood Lead Levels (µg/dl)
                       Before Intervention† After Intervention
Intervention           Mean (SD) Range Mean (SD) Range                       p-value*
Group

500 mg Ca              14.1 (8.1) 1.5-56.1     7.1 (2.7) 2.6-15.0            <0.0001

250 mg Ca              14.8 (7.5) 3.3-38.2     8.7 (4.5) 0.0-38.2            <0.0001

Without Ca             13.7 (7.5) 2.2-60.0    12.1 (6.8) 3.6-42.8            0.02


*p-value from the paired t-test for difference before and after intervention calculated for
each group separately
† There was no statistically significant difference in BLLs between the three groups
before the Ca supplement intervention (p>0.05)
Average distribution of BLLs
before and after interventions
             16

             14
                          p-value=0.50
             12

             10
Pb (ug/dl)




             8
                          p-value=<0.01
             6

             4

                                               Before
             2
                                               After
             0
                  No_Ca          Ca 250   Ca 500
  Proportion of blood lead levels ≥10 µg/dl
and percent reduction, by intervention group
                                        Intervention Group
                                  Without Ca 250 mg        500 mg    p-value
                                  (N=102)      (N=93)      (N=103)

    Proportion of BLL
    ≥10 µg/dl
       Before Intervention        62.3%       66.4%       68.5%       0.295
       After Intervention         52.9%       33.3%       17.5%       0.001


    Percent Reduction
    in Blood Lead                 15.1%       49.8%       74.5%      <0.001
    [(before-after)/before]*100
Final model of multivariate GEE* (N=298)
                                    Reduction of BLLs
                                  Coefficient     p

       Constant                     14.94       0.00
       Intervention Group
         Without Ca                  1.00       0.04
         250 mg Ca                  -2.36       0.01
         500 mg Ca                  -2.47
       Nutritional Status
         Good/Normal                 1.00       0.17
         Low                         1.17
       Time of trip to school
         < 5 minutes                 1.00       0.24
         5-15 minutes                1.28       0.48
         16-30 minutes              -0.29       0.64
         > 30 minutes               -0.63               * GEE model accounting
       Phase of data collection                         for repeated measures
                                                        and also clustering by
         Before intervention         1.00       0.00
                                                        school
         After intervention         -4.97
            CONCLUSION
Daily intake of Ca supplement for 3 months reduced
BLLs of children.
Intake of Ca supplement of 500 mg/day for 3
months reduced more BLLs than intake of Ca
supplement of 250 mg/day. The more intake of Ca
supplement, the more reduction of BLLs in children.
Nutritional status and duration of trip from/ to
school contribute in reducing BLLs of elementary
school children in Bandung along with Ca
supplement of 250 mg/day or 500 mg/day.
It is estimated that intake of Ca supplement of 250
mg/day for three months reduce 41.2% BLLs, and
intake of Ca supplement of 500 mg/day reduced
about 49.6% BLLs.
       RECOMMENDATION
Development of a program for consumption
 of food rich of Ca equals to 250 mg/day or
 500 mg/day, as a routine intervention to
 address difficulties in finding Ca
 supplement which children like, such as
 milk, milk products, fishes, small shrimps,
 small dry fishes, tofu, etc., is needed to be
 generated soon in Indonesia. This
 program will be effective when involving
 head of schools and school’s parent
 committee.