1. SERUM PCDD, PCDF AND PCB LEVELS IN SHELEKHOV FIREFIGHTERS Shelepchikov A.A. 1, Chernyak Y.I. 2, Grassman J.A. 3, Brodsky E.S. 1 V.G. Jilnikov 1, E. Ya. Mir-Kadirova 1 1 Institute of Ecology and Evolution of Russian Academy of Sciences, 33, Leninskiy pr., Moscow, 119071, Russia 2 Institute of Occupational Health and Human Ecology, East- Siberian Scientific Center of Human Ecology, Siberian Branch of the Russian Academy of Medical Sciences, P.O. Box 1170, Angarsk, 665827, Russia; 3 Brooklyn College- CUNY, 2900 Bedford Avenue, Brooklyn, NY 11210-2889, USA

2. SERUM PCDD, PCDF AND PCB LEVELS IN SHELEKHOV FIREFIGHTERS Shelepchikov A.A., Chernyak Y.I., Grassman J.A., Brodsky E.S. V.G. Jilnikov, E. Ya. Mir-Kadirova The “Irkutskcable” factory in the city of Shelekhov (Russia, Siberia) manufactures a wide range of plastic coated cable. The fire began on December, 24th, 1992 and proceeded for three days. An area of 16280 m 2 was destroyed along with more than 1000 tons of plastics including PVC. Total PCDD/Fs formation was estimated as 22 -57 g I-TEQ. Five special fire divisions from Irkutsk and Angarsk participated, Firefighters avoided using respirators and many of them subsequently developed a complex of neurological syndromes. 534 firefighters and 230 teaching officers and students from Firefighters School were involved, occupational diseases have been registered for 106 persons; the number of the died is not disclosed. “We attempted to cool the big heated unit in the cellar. We were standing waist-deep in an oily mixture when we were hit by the steam, we dived into this swill” - Grigory Gladkih, after 26 hours of working at the fire “In such extreme conditions we did not reflect on safety. Coming home, firemen felt unusually weak and dizzy. Their skin became covered by blisters. Years later we have learned that we were poisoned even though at first physicians assured us that it was a typical reaction due to our occupational exposure” - fireman Boris Karagulov.

3. SERUM PCDD, PCDF AND PCB LEVELS IN SHELEKHOV FIREFIGHTERS Shelepchikov A.A., Chernyak Y.I., Grassman J.A., Brodsky E.S. V.G. Jilnikov, E. Ya. Mir-Kadirova Four groups of 10 men each were formed: men who never worked as firefighters (Controls); firefighters who developed the Shelekhov Syndrome Complex soon after their participation at the fire (Shelekhov SC); firefighters who participated in the Shelekhov fire but did not develop the syndromes (Shelekhov non-SC); firefighters who did not participate in the 1992 Shelekhov fire (Firefighter controls). All samples were analyzed by GC -HRMS. WHO-TEQ DF serum level of Shelekhov firefighters is comparable with the indices typical for Firefighter controls. Although the means value for groups were not statistically different, the individual firefighter TEQs tend to be higher than the median of the non-firefighter controls. Serum (left) and body burden (right) PCDD and PCDF levels

4. SERUM PCDD, PCDF AND PCB LEVELS IN SHELEKHOV FIREFIGHTERS Shelepchikov A.A., Chernyak Y.I., Grassman J.A., Brodsky E.S. V.G. Jilnikov, E. Ya. Mir-Kadirova Body burden PCDD, PCDF and PCB levels, ng/body 1,2,3,4,6,7,8-HpCDF vs PCB-169 (pg/g lipid)

5. SERUM PCDD, PCDF AND PCB LEVELS IN SHELEKHOV FIREFIGHTERS Shelepchikov A.A., Chernyak Y.I., Grassman J.A., Brodsky E.S. V.G. Jilnikov, E. Ya. Mir-Kadirova The level of dioxin-like compounds was proportional to the number of years employed as a firefighter. Change of WHO-TEQ 05 PCDD/F concentration with age Serum WHO-TEQ 05 D/F by years working as a firefighter (top) – by years after cessation of work as firefighter (bottom). After cessation of work, the concentrations of these compounds show small increases consistent with those seen with aging. The body burden levels for the firefighters tends to exceed the levels of the 10 men from Control group.

6. SERUM PCDD, PCDF AND PCB LEVELS IN SHELEKHOV FIREFIGHTERS Shelepchikov A.A., Chernyak Y.I., Grassman J.A., Brodsky E.S. V.G. Jilnikov, E. Ya. Mir-Kadirova Slides 1, 3 and 6 contain original photos from the Shelehov fire This and others our posters are available at www.dioxin.ru/posters We are grateful to all people participating in the given research; and for financial support from Russian Foundation for Basic Research (RFBR) and U.S. Civilian Research & Development Foundation (CRDF) The study shows: -C-Current WHO-TEQ DF serum level for highly exposed firefighters is comparable with the indices typical for others working firefighters. -B-By comparison with the value for white non-Latin Americans, only the participants in the control group is similar. Levels of dioxin-like compounds among the firefighters are higher due to the contribution of non-dioxin-like PCBs -t-the PCB contribution exceeds 50% of the WHO-TEQ 98 and 40% - WHO- TEQ 05. -P-PCB-169 as well as 1,2,3,4,6,7,8-HpCDF can be considered reliable markers of exposure to combustion products exposure. -C-Concentration of PCB-169 in most of the former and working firefighters exceeds 90 percentile for the control group and higher levels remain after they stop working as firefighters.