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REPORT
7
Monitoring of EDC in the East-Asian hydrosphere: Report from The Philippines
Evangeline C. Santiago Head, Research and Analytical Service Laboratory,
Natural Sciences Research Institute, University of Philippines, Philippines
Monitoring of specific EDCs namely: alpha, beta, gamma and delta BHCs,
aldrin, dieldrin, endrin, p,p-DDE, p,p'-DDD and p,p'-DDT plus heptachlor
was done on surface riverine and bay waters in four provinces along
the western coast of the Philippines following the analysis protocol
of UNU for the project. The sampling sites were selected based on
some information that these sites would have probable contamination
due to known past applications of the EDCs in these areas.
Since the NSRI laboratory is interested in studies of the Philippines
environment, the research team took advantage of the sampling activities
of the project as opportunities to obtain bottom water samples, and
sediments in addition to the surface water samples prescribed by UNU
as study samples. NSRI plans to investigate the EDCs and the toxic
trace metals Arsenic, Mercury, Cadmium, Lead, Chromium VI and Copper
in all the collected samples if resources can be found for the analysis.
For each of the four provinces, three river sites and three coastal
sites sampled for water and sediments. Three grab samples for the
surface water, two for bottom water and three for sediments were obtained
for each site. Two sampling periods were observed, one in August to
September,1999 and the other in January, 2000.
This report covers only results for the EDCs in surface water samples.
Selected Ion Mode (SIM) Gas Chromatography/Mass Spectrometry (GC/MS)
analysis of the 72 samples collected during the first sampling resulted
zero detection of all the EDCs analyzed. Alpha-BHC was detected in
significant amounts (15-21 ng/L) in three of the 72 samples collected
in the second sampling period; one showed 7 ng/L of aldrin. However,
since the EDCs did not show in all the three grab samples collected
for each site, the results need verification.
Perhaps, because our laboratory is quite inexperienced in the GC/MS
analysis, and we got to learn the analysis on the job for this project
under a tight time pressure, much refinement is needed in our GC/MS
methods. But the first monitoring project on the EDCs gave us a good
experience in sampling out in the field, processing samples for recovery
of trace organics in the laboratory as well as a good opportunity
to learn the analysis of EDCs by SIM GC/MS. For us, this collective
experience is the biggest reward for our participation in the network
for the first year of the UNU-EDC Monitoring project.
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