engleski

Organochlorine pesticides and PCB congeners in suspended particulate matter collected in Zagreb

Semivolatile persistent organochlorine (OC) compounds were determined in samples of atmospheric particles PM10 collected daily during the year 2002 at one location in the northern, residential part of Zagreb. The compounds analysed were hexachlorobenzene (HCB), alpha-, beta-, and gamma-hexachlorocyclohexane (alpha-HCH, beta-HCH and gamma-HCH), 4, 4'-DDT, 4, 4'-DDE, 4, 4'-DDD and 20 polychlorinated biphenyl (PCB) congeners, including six indicator congeners (PCB-28, PCB-52, PCB-101, PCB-138, PCB-153, and PCB-180) and fourteen other toxicologically significant congeners (PCB-60, PCB-74, PCB-77, PCB-105, PCB-114, PCB-118, PCB-123, PCB-126, PCB-156, PCB-157, PCB-167, PCB-169, PCB-170 and PCB-189). Twenty-four-hour samples of PM10 particle fractions were collected on two glass microfibre filters from approximately 100 m^3 of ambient air per filter at the average air flow rate of 70 L/min. Fourteen filters with particle samples collected during seven consecutive days were combined for chemical analysis. OC compounds associated with particles were accumulated by ultrasonic extraction with 1:1 acetone:n-hexane mixture. The extracts were purified with sulphuric acid and analysed by high resolution gas chromatography with electron capture detection. The most frequently detected particle bound compounds in air were HCH isomers (gamma-HCH in 100 %, alpha-HCH in 96 % and beta-HCH in 88 % of samples), DDT type compounds (4, 4'-DDE in 87 %, 4, 4'-DDT in 79 % and 4, 4'-DDD in 38 % of samples) and HCB (in 85 % of samples). The median concentrations in air of different OC pesticides sorbed in PM10 ranged from 0 to 6 pg/m^3. The most frequently detected PCB congeners were PCB-28 (in 65 % of samples), PCB-60 (in 63 % of samples), PCB-101 (in 58 % of samples) and PCB-180 (in 56 % of samples). The highest mass concentration was determined for PCB-28: 101 pg/m^3. The decreasing trend in mass concentrations of particle bound beta-HCH and total PCBs with increasing air temperature was mostly related to the lower particle mass concentrations at higher temperatures.

Organochlorine pesticides; polychlorinated biphenyls; suspended particulate matter; PM10

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