Unreliable researcher? The credibility of Dr. Shinsuke Tanabe (centre left, wearing glasses) has been called into question by Cambodia's Ministry of Environment.

The Cambodian Ministry of Environment (MOE) is challenging recently released Japanese

research results that concluded Phnom Penh's Stung Meanchay dump was highly contaminated

with dioxin and heavy metals.

Heng Nareth, Director of the MOE's Pollution Control Department, told the Post on

Jan 30 that the toxicological methodology of Dr. Shinsuke Tanabe of Japan's Ehime

University's Center for Marine Environmental Studies was flawed and produced results

completely opposite to those of an MOE study.

Tanabe released the results of a two-year study of soil and human tissue samples

taken from the dump in Dec 2000, indicating potentially lethal levels of dioxin and

heavy metals such as arsenic, mercury and cadmium.

However Nareth says that Tanabe ignored the testing protocol necessary for reliable

and accurate measurement of dioxin in the environment and in human tissue, making

his test results highly suspect.

"[Tanabe] didn't do a proper toxicological study, which would take intensive

testing over a two to three year period," Nareth said. "Tanabe visited

Cambodia two or three times over two years [to take samples at the dump], but accurate

and reliable dioxin testing requires testing several times within each year [of a

test period]."

Nareth says that Tanabe's test results were also compromised by a lack of thorough

background checks of the dump residents from whom he took hair, fingernail and breast

milk samples.

"He should have studied the background of the study's participants," Nareth

said. "Some people [who gave samples] could have been there only a day or a

week."

According to Nareth, the quality of Tanabe's research is thrown into even more doubt

by the results of a rival MOE-sponsored study undertaken by the Ebara Corporation,

a division of Mitsubishi.

While Tanabe's research uncovered what he described as "dangerously high"

levels of heavy metals at the dump, the results of the Ebara Corporation study, conducted

in October, 2000, indicated precisely the opposite.

"The amount of heavy metals in the soil are not considered as pollutants based

on...Japanese regulations on compost," the Ebara Corporation report states.

Tanabe declined to respond to Post e-mail enquiries regarding the MOE objections

to his research.