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soil SAMPLES from north Vietnam Mountain As A Key to Clue OCDD PheNOmEna

soil SAMPLES from north Vietnam Mountain As A Key to Clue OCDD PheNOmEna. Andrey Shelepchikov , Efim Brodsky, Olga Vasina Institute of Ecology and Evolution, Russian Academy of Sciences, Moscow,Russia ; Russian-Vietnamese Tropical Center, Hanoi, Vietnam.

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soil SAMPLES from north Vietnam Mountain As A Key to Clue OCDD PheNOmEna

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  1. soil SAMPLES from north Vietnam Mountain As A Key to Clue OCDD PheNOmEna AndreyShelepchikov, Efim Brodsky, Olga Vasina Institute of Ecology and Evolution, Russian Academy of Sciences, Moscow,Russia; Russian-Vietnamese Tropical Center, Hanoi, Vietnam

  2. Location – north Vietnam, Lao Cai province, Sa Pa district, national park Hoang Lien

  3. PCDD/Fs and PCP concentration in soil samples Fact Supposition The OCDD hot-spot-flattopof a hill(~100 м2, abovesealevel~ 2120 m); mostlikelyoriginalpollutionwasdotted. The neighbortop(~500 m on a straightline)isnot polluted Historical contamination or atmospheric deposition accumulation are less probable The source of pollution has been brought by the human Forest's fire could not be a course of contamination Forest fire was not long ago. Only trace amount of PCDFs were found Plastic bag could contain some chemicals. The fragments the plastic bag for loose goods have been found on the hot-spot PCP salt and it’s water soluble impurities could be eluted by rains. OCDD could not be formed in technological processes without PCDFs If we accept that OCDD pollution is caused by PCP, we should allow that stability of OCDD is much higher than other PCDD/Fs or OCDD could form in-situ in soil. Neither chlorinated compounds has not been found in samples on OCDD concentration level PCP level in the hot-spot is low, but higher than in other soil samples

  4. The samples were analyzed by HRGC/HRMS (НР 6890 Plus / Finnigan MAT 95XP with an upgraded cooling system) using SGE BPX-5 column. PCDD/Fswere analyzed by typical procedure. Full-scan experiments were run at different scan rate and m/z interval, in order to obtain the most detail mass-spectrum. Mass measuring precision was controlled by 13C6-PCP, D8-DDD and native OCDD ions; in most full-scan runs, it was ± 0,02amu. We analyze organic (toluene:acetone) and basic extracts from soil samples without any clean-up or after passing through the micro column with sulfuric acid on silica gel. TIC chromatogram and OCDD mass-spectrum of soil sample from OCDD hot-spot (m/z 180-520, 2s/d, R=8000). unidentified unidentified

  5. Identification criteria: • Exact m/z • Characteristic EI mass fragmentation pattern with presence at least five isotope ion clusters corresponding loss of neutral particles СН3, (СН3+СО) and Cl • Rupture of Ar-O-Ar bond at biphenyl ethers • True isotopic ratio for 4-5 main ions in molecular and fragmental clusters

  6. We assume We identified Tens injections Hundreds MID windows Thousand mass spectra Much more in plans Not all are conceived Now ...... ? This and others our posters are available at www.dioxin.ru/posters Any ideas are welcome at dioxin@mail.ru

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