Investigation of organic xenobiotic transfers, partitioning and processing in air-soil-plant systems using a microcosm apparatus. Part I: Microcosm development

A microcosm system was developed to investigate transfers of organic xenobiotics in air-soil-plant systems. This was validated using C-14 labelled 1,2-dichlorobenzene (DCB) as a model compound. Trapping efficiency was 106 +/- 3 % for volatile compounds and 93.0 +/- 2.2 % for carbon dioxide in a blank microcosm arrangement. Recovery of 1,2-dichlorobenzene spiked to grassed and unplanted soils was > 90 % after 1 week. The predominant DCB loss process was volatilisation with no evidence for mineralisation over 1 week and 20 - 30 % of the added spike remained in soil. Although there was no evidence for root uptake and translocation of added label, foliar uptake of soil volatilised compound was detected. The microcosm showed good potential for study of C-14 labelled and unlabelled organic xenobiotic transfers in air-soil-plant systems with single plants and also intact planted cores. (C) 1999 Elsevier Science Ltd. All rights reserved.