Transpiration effect on the uptake and distribution of bromacil, nitrobenzene, and phenol in soybean plants

Journal Article · · J. Environ. Qual.; (United States)

OSTI ID:5588797

McFarlane, J C; Pfleeger, T; Fletcher, J

The influence of transpiration rate on the uptake and translocation of two industrial waste compounds, phenol and nitrobenzene, and one pesticide, 5-bromo-3-sec-butyl-6-methyluracil (bromacil), was examined. Carbon-14 moieties of each compound were provided separately in hydroponic solution to mature soybean plants maintained under three humidity conditions. The uptake of each compound was determined by monitoring the removal of /sup 14/C from the hydroponic solution. The extent to which /sup 14/C was adsorbed to roots and translocated to plant shoots and leaves was examined by assaying root and shoot parts for /sup 14/C. Bromacil was taken up slower than the other chemicals, had the most /sup 14/C translocated to the shoot, and the amount translocated to the shoot responded directly to the rate of transpiration. In contrast, both phenol and nitrobenzene were rapidly lost from solution and bound to the roots. Less than 1.5% of the /sup 14/C from phenol or nitrobenzene was translocated to the plant shoots. Increased transpiration rates had little influence on root binding of /sup 14/C; however, increasing transpiration rate from low to medium was associated with an increased uptake of nitrobenzene. The three chemicals studied have similar Log K/sub ow/ values, but their interactions with soybean were not the same. Thus, despite the usefulness of the octanol/water partitioning coefficient in predicting the fate of organic chemicals in animals and in correlating with root binding and plant uptake for many pesticides, log K/sub ow/ may not be equally useful in describing uptake and binding of nonpesticide chemicals in plants.

• Research Organization: Environmental Protection Agency, Corvallis, OR
• OSTI ID: 5588797
• Journal Information: J. Environ. Qual.; (United States), Journal Name: J. Environ. Qual.; (United States) Vol. 16:4; ISSN JEVQA
• Country of Publication: United States
• Language: English

Related Subjects

550501 -- Metabolism-- Tracer Techniques
560300* -- Chemicals Metabolism & Toxicology
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AROMATICS
AZINES
BACTERIA
CARBON 14 COMPOUNDS
COMPARATIVE EVALUATIONS
GLYCINE HISPIDA
HETEROCYCLIC COMPOUNDS
HYDROXY COMPOUNDS
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
LEGUMINOSAE
MICROORGANISMS
NITRO COMPOUNDS
NITROBENZENE
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PHENOL
PHENOLS
PLANTS
PYRIMIDINES
RHIZOBIUM
TRACER TECHNIQUES
TRANSPIRATION
UPTAKE
URACILS