Factors affecting uptake of lead by plants

Thesis/Dissertation · Mon Jan 01 04:00:00 EST 1973

OSTI ID:6001980

Arvik, J H

Studies of the factors affecting the uptake of lead by plants were performed using important agricultural crops as test organisms and exposing them to particles containing lead species found in automobile exhaust. Lead solutions were added to soils and the subsequent ability of plants to absorb lead from the soils was studied. For soils of three texture classes, addition of lead solutions to the surface until soil moisture saturation occurred resulted in stratification, with more than 95% of the lead remaining in the top cm. No added lead was found below the 3rd cm in any of the soils. Plant uptake of lead in a sandy loam decreased as lead residence time in the soil increased up to approximately 48 hr. Virtually all of the lead added to plants as aerosols could be removed by chloroform rinse or mild acid washes, suggesting that the lead remained as a topical coating on the foliage. No significant amount of lead could be found in roots, fruit, or new growth of the shoots following exposure to lead aerosols. Cuticles of plant foliage and fruit were studied to determine the ability of these structures and their waxes to prevent movement of lead into the leaf. Only extremely small amounts of lead could penetrate the cuticle, even after extended exposure. Removal of the waxes permitted increased penetration of some cuticles, and penetration seemed more related to species of plant than to weight of cuticle. Absorption of lead by plant roots was studied in the presence of varied pH, low temperature, and metabolic inhibitors. Optimum uptake of the metal occurred at pH 4.5-5.5, with reduced uptake at more acid or neutral conditions. Low temperatures reduced uptake by less than 40%; this loss could be attributed to viscosity differences in the solution and the plant material. Metabolic inhibitors did not inhibit uptake of lead by plant roots. 52 references, 11 tables.

• OSTI ID: 6001980
• Country of Publication: United States
• Language: English

Related Subjects

500200 -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
510200 -- Environment
Terrestrial-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
560303* -- Chemicals Metabolism & Toxicology-- Plants-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ABSORPTION
AEROSOLS
AIR POLLUTION
AUTOMOBILES
COLLOIDS
COMPARATIVE EVALUATIONS
DATA
DEPOSITION
DISPERSIONS
ELEMENTS
ENVIRONMENTAL TRANSPORT
EXHAUST GASES
EXPERIMENTAL DATA
FLUIDS
FOLIAR UPTAKE
GASEOUS WASTES
GASES
INFORMATION
LEAD
MASS TRANSFER
METALS
NUMERICAL DATA
PH VALUE
PLANTS
POLLUTION
ROOT ABSORPTION
SOILS
SOLS
UPTAKE
URBAN AREAS
VEHICLES
WASTES