&EPA
United States
Environmental Protection
Agency
Office of Chemical Safety
and Pollution Prevention
(7101)
EPA712-C-002
January 2012
Ecological Effects
Test Guidelines
OCSPP 850.4800:
Plant Uptake and
Translocation Test
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NOTICE
This guideline is one of a series of test guidelines established by the United States
Environmental Protection Agency's Office of Chemical Safety and Pollution Prevention
(OCSPP) for use in testing pesticides and chemical substances to develop data for
submission to the Agency under the Toxic Substances Control Act (TSCA) (15 U.S.C. 2601,
et seq.), the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) (7 U.S.C. 136, et
seq.), and section 408 of the Federal Food, Drug and Cosmetic (FFDCA) (21 U.S.C. 346a).
Prior to April 22, 2010, OCSPP was known as the Office of Prevention, Pesticides and Toxic
Substances (OPPTS). To distinguish these guidelines from guidelines issued by other
organizations, the numbering convention adopted in 1994 specifically included OPPTS as
part of the guideline's number. Any test guidelines developed after April 22, 2010 will use
the new acronym (OCSPP) in their title.
The OCSPP harmonized test guidelines serve as a compendium of accepted scientific
methodologies and protocols that are intended to provide data to inform regulatory decisions
under TSCA, FIFRA, and/or FFDCA. This document provides guidance for conducting the
test, and is also used by EPA, the public, and the companies that are subject to data
submission requirements under TSCA, FIFRA, and/or the FFDCA. As a guidance
document, these guidelines are not binding on either EPA or any outside parties, and the
EPA may depart from the guidelines where circumstances warrant and without prior notice.
At places in this guidance, the Agency uses the word "should." In this guidance, the use of
"should" with regard to an action means that the action is recommended rather than
mandatory. The procedures contained in this guideline are strongly recommended for
generating the data that are the subject of the guideline, but EPA recognizes that departures
may be appropriate in specific situations. You may propose alternatives to the
recommendations described in these guidelines, and the Agency will assess them for
appropriateness on a case-by-case basis.
For additional information about these test guidelines and to access these guidelines
electronically, please go to http://www.epa.qov/ocspp and select "Test Methods &
Guidelines" on the left side navigation menu. You may also access the guidelines in
http://www.regulations.gov grouped by Series under Docket ID #s: EPA-HQ-OPPT-2009-
0150 through EPA-HQ-OPPT-2009-0159, and EPA-HQ-OPPT-2009-0576.
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OCSPP 850.4800: Plant uptake and translocation test.
(a) Scope—
(1) Applicability. This guideline is intended to be used to help develop data to submit to
EPA under the Toxic Substances Control Act (TSCA) (15 U.S.C. 2601, et seq.), the
Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) (7 U.S.C. 136, et seq.), and
the Federal Food, Drug, and Cosmetic Act (FFDCA) (21 U.S.C. 346a).
(2) Background. The source material used in developing this harmonized OCSPP test
guideline is the OPPT guideline under 40 CFR 797.2850 Plant Uptake and Translocation
Test.
(b) Purpose. This guideline is intended for use in developing data on the uptake and
translocation, by terrestrial plants, of chemical substances and mixtures ("test chemicals" or "test
substances") subject to environmental effects test regulations. This guideline describes tests
using commercially important terrestrial plants to develop data on the quantity of test substances
incorporated in plant tissues and the potential for entry into food chains with resultant indirect
human and/or wildlife exposure. The test design is a composite of prior plant experiments in
which the uptake of heavy metals, pesticides, or organic chemicals has been investigated (see
paragraphs (j)(2) to (j)(12) of this guideline). Test substances of concern may be transported to
various sites as gases or dust, solubilized in preparation or in irrigation water, or may be
encountered in soils. It is well known that plants readily take up, translocate, accumulate, and
metabolize chemicals that are non-essential for plant growth and development. Such uptake and
incorporation often represents the first step in the transport of these substances within terrestrial
food webs. The uptake and translocation test addresses this concern of entry into food webs.
This test is not concerned with toxicity to plants; it deals with hazard to animals and the potential
for indirect human exposure. The Environmental Protection Agency will use data from this test
to assess the hazard or risks a test substance may present in the terrestrial environment. This
guideline should be used in conjunction with the OCSPP 850.4000 guideline, Background and
special considerations for conducting ecological effects tests with terrestrial and aquatic plants,
cyanobacteria, and terrestrial soil core microcosms.
(c) Definitions. The definitions in the OCSPP 850.4000 guideline apply to this test guideline.
In addition, the following more specific definitions also apply:
Mass balance refers to a quantitative accounting of the distributions of test substance in
plant components, support media, and test solutions. For gas fumigation with the test
substance, it also refers to a quantitative determination of uptake as the difference
between the quantity of gas entering an exposure chamber, the quantity leaving the
chamber, and the quantity adsorbed to the chamber walls.
Translocation is the transference or transport of chemical from the site of uptake to other
plant components.
Uptake refers to a process by which substances are transferred into a terrestrial plant.
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(d) General considerations—
(1) Summary of the test. In preparation for the test, seeds are planted in potting
containers (or in cotton or glass-wool plugs supported in hydroponic solution) and, after
germination, seedlings are thinned, by pinching the stem at the support surface to 1 to 3
plants per pot, depending on the species, and discarding the pinched off seedlings.
Potting mixtures of sand, glass beads or soil are subirrigated with nutrient solution. The
test substance is applied to the plants via nutrient solution or adsorbed to the support
media to produce a root exposure scenario; or applied to the plants by either spraying or
dusting the foliage or exposing the plants to gas in a fumigation chamber to produce a
foliar exposure scenario. An alternative root exposure scenario involves application of
the test substance to soil after the seeds have been planted but prior to germination.
Plants are then harvested when there is either adequate material for analysis or until fruit
or seeds are mature. If plants are fumigated, either rates of uptake and surface adsorption
should be calculated, or the plants may be harvested and analyzed for test chemical and
residues. The primary endpoints for the plant uptake and translocation test are the
concentrations of free parent test substance, metabolites and soluble residues, and bound
residues in pooled plant organs and pooled whole plants. For gaseous test substances, in
addition to or in lieu of these measurements, calculated measurements of photosynthesis,
transpiration, and stomatal conductance before, during, and after exposure to the test
substance are made.
(2) General test guidance. The general guidance in the OCSPP 850.4000 guideline
applies to this test guideline, except as specifically noted herein.
(3) Range-finding test. A range-finding test is usually conducted to establish the
appropriate test concentrations to be used for the definitive test.
(i) Because of the different mechanisms involved in root and leaf uptake, and to
more closely define the chemical concentrations to be used in the uptake test, the
definitive early seedling growth test (see the OCSPP 850.4230 guideline) is
recommended as the range-finding test for tests with industrial chemicals. The
exposure technique used in the early seedling growth test (root or foliar exposure)
should reflect the anticipated fate of the test substance. The concentration
selected as the upper limit for the uptake and translocation test should be near to
but below the threshold of visible injury (e.g., NOEC). Short exposure periods to
gas in fumigation chambers are not expected to promote visible injury or gross
reductions in growth but may alter stomatal resistance, transpiration, or
photosynthesis. Absorption and adsorption rates may be calculated and gas
concentrations for definitive testing selected based on the calculated sorption
rates.
(ii) Alternatively, a seed germination or root elongation test or other appropriate
phytotoxicity test (see paragraph (j)0) °f this) may be used to establish the
appropriate upper concentration for testing. For tests with pesticides, which are
applied to surface soil, the seedling emergence and seedling growth test (see the
OCSPP 850.4100 guideline) is recommended as the range-finding test.
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(4) Definitive test. The purpose of the definitive uptake and translocation test is to
determine the propensity for a test substance to accumulate in plants or plant parts. The
test substance should be added to the hydroponic or nutrient solution, coated on glass
beads, or applied to the soil surface (for the root uptake test); or sprayed, dusted, or
gassed directly on the foliage (for the foliage uptake test). Two different plant species are
used. The test consists of one run for each of the two specified plant species. For a
particular chemical, a run is defined as exposure of the plant species to three
concentrations of the test chemical with a minimum of six replicate pots per treatment
level and appropriate controls. Exposure is followed by extraction and analysis for parent
compound, metabolites, and bound residues in plant tissues for solid and liquid test
substances and by calculating these values and/or rates of absorption and adsorption for
gas test substances. Analytical confirmation of the test concentrations in exposure media
is performed as described in the OCSPP 850.4000 guideline. The elements of an
acceptable or valid definitive test are given in Table 3 of this guideline.
(e) Test standards—
(1) Test substance. For industrial chemicals, the substance to be tested should be
technical grade unless the test is designed to test a specific formulation, mixture, or end-
use product. For pesticides the substance to be tested is the typical end-use product
(TEP). If there is more than one TEP with the same inert substances, the one with the
highest percent active ingredient (a.i.) and/or the one most commonly used should be
tested. If there is more than one TEP with different inert substances, a TEP
representative of each different inert substance should be tested in the range-finding test
and at a minimum the most sensitive one tested in the definitive test. In addition, if an
adjuvant is recommended for use on a TEP label, the adjuvant is added with the TEP at
the label rate to constitute the test substance. If a TEP is not available (i.e. new
pesticide), the technical grade a.i. is used with a representative formulation, which should
include any adjuvant that will be recommended for use on the label. The OCSPP
850.4000 guideline lists the type of information that should be known about the test
substance before testing, and discusses methods for preparation of test substances.
(2) Test duration. The duration of the exposure period, for solid and liquid test
substances, should be equal to the length of time required for the particular test species to
achieve sufficient biomass for analysis or until fruit or seeds are mature. Carrot, lettuce,
onion, cabbage, and ryegrass may be harvested whenever there is adequate plant material
for chemical analysis. Cucumber, corn, soybean, tomato, and oats should be grown until
fruit or seed are mature. The test duration for gaseous test substances should be similar,
or may be reduced to the length of time required to make the specified gas exchange
measurements if these measurements are used as the test endpoints.
(3) Test organism—
(i) Species.
(A) The test is performed using two plant species of potentially differing
sensitivity, such as a monocotyledonous and a dicotyledonous species. It
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is further suggested that the test plants selected should be of different
growth forms, e.g., a root crop and a leaf crop. Plant species and groups
recommended for testing are listed in Table 1.
(B) A listing of some additional plant taxa that have been used in toxicity
tests can be found in the reference in paragraph (j)(l) of this guideline.
Use of these alternative species should be submitted to and reviewed by
the Agency prior to conduct of the study. Endangered or threatened
species as determined by the Endangered Species Act of 1973 (Public Law
93-205) may not be used without permission from the Fish and Wildlife
Service.
Table 1.—Species and families acceptable for the plant uptake and translocation test
Family
Dicots Solanaceae
Cucurbitaceae
Asteraceae
Fabaceae1
Brassicaceae
Apiaceae
Chenopodiaceae
Asteraceae
Fabaceae
Brassicaceae
Brassicaceae
Fabaceae
Malvaceae
Polygonaceae
Monocots Poaceae
Poaceae
Poaceae
Liliaceae
Species
Lycopersicon esculentum or
Solarium lycopersicum
Cucumis sativus
Lactuca sativa
Glycine max
Brassica oleracea
Daucus carota
Beta vulgaris
Helianthus annuus
Pisum sativum
Brassica rapa
Brassica napus
Phaseolus vulgaris
Gossypium spp.
Fagopyrum esculentum
Avena sativa
Lolium perenne
Zea mays
Allium cepa
Common name
Tomato
Cucumber
Lettuce
Soybean
Cabbage
Carrot
Sugar beet or table beet
Sunflower
Pea
Field mustard, Canola
Rape, Turnip
Garden bean
Cotton
Buckwheat
Oat
Perennial ryegrass
Corn
Onion
Inoculation with Rhizobiumjaponicum is unnecessary
(ii) Source. Within a given test, all test organisms of a given species, including
the controls, should be from the same source and lot number.
(iii) Growth stage at test initiation.
(A) Except for surface soil applications, newly germinated plants are used
at test initiation for root (applied in nutrient solution or sorbed to support
medium) and foliage exposures. The plants should be exposed from
seedlings through maturation when monitoring residues in fruit or seeds.
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(B) Where the test substance is applied or deposited on the soil surface,
the test is initiated using seeds which have been planted but have not yet
germinated.
(iii) Condition. Healthy seeds should be used to generate seedlings. Within a
given test, all test organisms of a given species, including the controls, should be
selected to have uniform size. Seeds should be selected from a single class size
within each species. The seeds of most test species are sorted by the supplier
according to size; however, if necessary, the seeds should be further sorted prior
to use to provide a more uniform size class that reduces the potential for bias from
testing different sizes of seed. In addition broken or damaged seeds should be
separated from those used in the test and discarded.
(iv) Care and handling.
(A) Seeds should be stored in a dessicator and refrigerated until needed.
(B) Pesticide treated seeds should be avoided. The Agency should be
consulted prior to test initiation if seed treatments other than a weak
hypochlorite solution (recommended by Environment Canada), captan, or
thiram are used. Captan and thiram seed treatments are the only approved
pesticide seed treatments (non-systemic with most other pesticides; see
paragraph (j)(9) of this guideline). Steam sterilization of soil is
recommended as a non-pesticide alternative for killing pathogens, fungi,
and insects in soil media. When unapproved pesticide seed treatments are
used in a study, the test should be designed to demonstrate no synergistic
or antagonistic interactions occur between or among the seed treatment
and test substance.
(C) If plants are to be grown hydroponically seeds should be planted in
plugs of cotton or glass-wool supported in the tops of the containers.
When sand or glass beads are used, the recommended planting procedure
is to fill potting containers with sand or glass beads to within 2.5
centimeters (cm) of the top and to sow seeds directly on the support
medium.
(D) When soil is used, for pesticides, the recommended planting procedure
is to fill potting container with soil medium (see the OCSPP 850.4100 or
OCSPP 850.4150 guidelines) to within 2.5 cm of the top and sow seeds in
the soil.
(E) A sufficient number of seeds should be planted (e.g. 30) to provide
more seedlings than called for in the test. After 50 percent (50%) of the
seeds have germinated, the seedlings should be thinned, by pinching the
stem at the support surface, to the desired number (typically, one to four
per pot, depending upon the species). Any plants subsequently emerging
are also pinched off.
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(F) Alternate planting methods may be required when the test substance is
highly volatile. An impervious barrier of polyethylene film, a
modification of the double pot method, a glass plate, or other appropriate
apparatus should be used to prevent volatilization from the root zone.
Seeds should be germinated in the dark at 25 degrees Celsius (°C) and
seedlings with radicle length in the median range transplanted into the
potting containers. The seedlings should be positioned such that their
roots are exposed to the support media while the shoots pass through holes
in the barrier. A ring of inert, non phytotoxic, pliable putty should be used
to seal the holes around the stems. Control pots should be handled
identically except there is no exposure to the test substance. This
transplanting procedure, without the volatilization barrier, is also
recommended when the test substance is adsorbed to the support medium.
(4) Administration of test substance—
(i) Exposure pathway. The choice of exposure technique is dependent upon the
expected route of exposure of plants in the environment and the form of the test
substance.
(A) Root exposure.
(1) If the anticipated fate of the test substance is incorporation into
soil or soil-water, and the mechanism of concern is root uptake, the
test substance should be applied in nutrient solution to the root
support media, or coated on sand or glass beads (for non-water-
soluble test substances).
(2) For pesticides where the test substance is expected to be
applied or deposited on the soil surface, the test substance should
be applied to the soil surface prior to germination of seed but after
the seeds have been planted.
(B) Foliar exposure. With a test substance whose anticipated mode of
exposure to plants is surface deposition by atmospheric transport or
irrigation water, the appropriate testing method may be foliar application
(accomplished by spraying, dusting, or fumigating the plants), allowing
subsequent movement into the rooting zone with watering.
(ii) Preparation of exposure treatment—
(A) Root exposure. Except for test substances that are purposely applied
to surface soil (such as pesticides), root exposure is accomplished by
adding the test substance to the nutrient medium (or hydroponic solution)
used to subirrigate the plants, as described in paragraphs (e)(4)(ii)(A)(7j
and (e)(4)(ii)(A)0 of this guideline for soluble and insoluble test
substances, respectively, or by sorbing the test substance to the sand or
glass beads used as support medium, as described in paragraph
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of this guideline. The test substance is repeatedly applied
through the subirrigation scenario, while the test substance is only applied
once when it is sorbed on the support medium. For hydroponic solutions
the entire test solution should be replaced weekly or earlier if the
concentration of test substance in the test or nutrient solution varies by
more than 20% of that specified. Methodology for surface soil
applications for pesticides are described in paragraph (e)(4)(ii)(A)(^) of
this guideline.
(1) Test substances that are soluble in water should be dissolved in
the nutrient solution just prior to the beginning of the test. Reagent
water should be used in making stock solutions of the test
substance. Sufficient quantities of each concentration should be
made up as needed to minimize storage time and disposal volume.
The OCSPP 850.1000 and OCSPP 850.4000 guidelines contain
additional information on preparation of stock solutions.
(2) Test substances that are insoluble in water but which can be
placed in aqueous suspension with a vehicle should be added to the
nutrient solution. The vehicle should be soluble in water,
relatively nontoxic to plants, and should be used in the minimum
amount required to dissolve or suspend the test substance. There
are no preferred vehicles; however, acetone, gum arable,
polyethylene glycol, ethanol, and others have been used
extensively in testing herbicides, plant growth regulators,
fungicides, and other chemicals that affect plants. Vehicle controls
should be included in the experimental design and tested
simultaneously. The OCSPP 850.4000 guideline contains
additional information on preparation of stock solutions using a
vehicle.
(3) Water-insoluble test substances for which no nontoxic, water-
soluble vehicle is available, should be dissolved in an appropriate
volatile solvent. The solution should be mixed with the sand or
glass beads which are then placed in a rotary vacuum apparatus
and evaporated, leaving a uniform coating of test substance on the
sand or beads. A weighed portion of sand or beads should be
extracted with the same organic solvent and the concentration of
test substance determined before the potting containers are filled.
Solvent controls are included in the experimental design and tested
simultaneously.
(4) For the surface soil exposure scenario, the test substance is
applied to the soil surface after planting the seeds and prior to
germination. For pesticides, this is typically accomplished using a
properly calibrated sprayer after the seeds have been planted. At
test initiation, test substance is applied to surface soil immediately
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after the seeds have been planted using a properly calibrated
sprayer. The amount of water used in the spray as a carrier is
equivalent to the recommendation on the pesticide label. For
example, vegetation within a given pot (test container) is sprayed
with x milligrams of TEP mixed into 10 milliliters of water, where
the 10 milliliters of water per the pot area is equivalent to the
minimum number of gallons of water per acre specified on the
label. For a satisfactory test, all pots in all treatment levels and
controls have the same equivalent volume of water applied (e.g., in
the example just given this is 10 milliliters). Additional
information can be found in the OCSPP 850.4100 guideline.
(B) Foliar exposure. Foliar exposure is accomplished by spraying the
plants, as described in paragraph (e)(4)(ii)(B)(7y) of this guideline by
dusting the plants, as described in paragraph (e)(4)(ii)(B)f2y) of this
guideline or by exposing the plants to gas in a fumigation chamber, as
described in paragraph (e)(4)(ii)(B)(3y) of this guideline. The test substance
is applied weekly via spraying or dusting, but only applied once when the
fumigation scenario is used.
(1) Water soluble test substances should be dissolved in reagent
water just prior to use. Test substances that can be suspended in an
aqueous solution by a vehicle should be prepared as described in
paragraph (e)(4)(ii)(A)(7y) of this guideline except using reagent
water not nutrient solution. Sufficient quantities of each test
concentration should be made up as needed. These solutions
should be applied at weekly intervals. Plants should be placed in
an exhaust hood and the test substance applied to the foliage. A
plastic sleeve may be fitted over the top of the pot, and the foliage
sprayed with specific quantities of test solution at known
concentrations. The plastic sleeve, confining the test substance to
plant and pot, facilitates expression of test substance dosage as
quantity per pot area (i.e., micrograms per square meter). Shoots
of control plants should also be sprayed, in an identical manner,
with reagent water. In addition, a vehicle control group is included
if a vehicle was used to prepare the test substance. Alternatively, a
miniature compressed-air sprayer may be mounted on a pendulum
and equipped to automatically spray a plant positioned directly
beneath the center of its arc of swing. Track or belt sprayers may
also be used (see the OCSPP 850.4000 and OCSPP 850.4100
guidelines for additional information). When radioisotope-labeled
test substances are applied, health and safety considerations
prohibit spray application. Instead, specific quantities of labeled
chemical should be applied directly to leaves in single drops.
(2) Water-insoluble test substances, existing as solids, may be
prepared for testing by grinding or other reduction methods to
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particles of smaller than 200 micrometers (|im) in diameter. These
test substances should be applied at weekly intervals. Plants
should be placed in an exhaust hood, a plastic sleeve fitted over the
top of the pot, and a specific quantity of test substance sprinkled
uniformly over them. Prior to test substance application, plants
should be misted with water to promote foliar retention of the test
substance. Control plants are also misted with reagent water at
each treatment date and dusted with an inert substance of the same
particle size as the test substance. Applications are expressed as
quantity per unit pot area (i.e.., micrograms per square meter).
(3) Test substances existing in gaseous form at normal ambient
temperatures and pressures can be generated for use as needed or
stored under pressure. The bottled gas may be 100% pure test
substance or may be mixed with an inert carrier, such as nitrogen,
to known concentrations. Controlled or measured concentrations
of test substance should be metered into the exposure chamber,
uniformly mixed about the plants, and exhausted through the outlet
port where the flow rate and concentration are again measured.
Use of this system design provides an alternate method of analysis
if the quantity of test substance sorbed by plants is less than that
required for chemical analysis. Plants should be fumigated
whenever they have reached sufficient size for measurement of
photosynthesis and transpiration rates, assuming equivalent
detection sensitivity of carbon dioxide, water vapor, and chemical
analyzers. The appropriate size is a function of the gas exchange
system and constitutes an area of expert judgment.
(iii) Treatment levels.
(A) For this determination, at least three concentrations of the test
substance, exclusive of controls, are tested. Recommended concentrations
would be a descending geometric progression from the upper
concentration tested {i.e. 100, 50, 25 milligrams per liter (mg/L)). The
concentration selected as the upper limit for the uptake and translocation
test should be near to but below the threshold of visible injury (e.g.,
NOEC). Short exposure periods to gas in fumigation chambers are not
expected to promote visible injury or gross reductions in growth but may
alter stomatal resistance, transpiration, or photosynthesis. Absorption and
adsorption rates may be calculated and the upper limit for the uptake and
translocation test for definitive testing selected based on the calculated
sorption rates.
(B) The use of pesticide treatments to control pests during the test should
be avoided. Mechanical, cultural, and biological pest control methods are
suggested. If pesticide treatments are used in the test for pest control, for a
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satisfactory test there should be a negative control and a control with only
the treatments used for infestation purposes.
(iv) Introduction of test organisms. Seedlings used in testing are produced by
planting seeds of the desired species in the selected support medium and allowing
them to germinate, at which time they are thinned to 1-4 plants of similar size and
condition, such that there is no crowding or competition among the plants at
harvest or maturity. Within a given test, all test organisms of a given species,
including the controls, must be from the same source and seed lot. For a
satisfactory test, a system of impartial or random assignment of the seeds to the
pots and the pots to test and control groups is used to prevent bias.
(5) Controls.
(i) Every test includes controls consisting of the same support medium,
conditions, procedures, and test population, except that no test substance is added.
In addition, vehicle (solvent) controls are also included if a solvent is used.
(ii) Seed germination standards.
(A) For a satisfactory test, seed germination percentage in each of the
controls should be at least 65%; or the percentages in minimum acceptable
United States Department of Agriculture (USDA) seed germination
standards listed in paragraph (e)(5)(ii) of this guideline. For native species
that do not have germination standards, sufficient numbers of seeds should
be used to insure the identified number of seedlings per pot for test
initiation.
(B) The following minimum acceptable USDA seed germination (control)
standards for vegetable crops (as described in the Federal Seed Act
Regulation, 7 CFR parts 201-202) and other available standards for
agronomic crops will be used: Field corn (85%), pop corn (75%), sweet
corn (75%), carrot (55%), onion (70%), tomato (75%), field-garden bean
(70%), pea (80%), cabbage (75%), lettuce (55%), mustard—all types
(75%), soybean (75%), sugar beet (55%), small grains—wheat, oats,
barley, rice (80%), ryegrass (75%), and rape (75%). Refer to regulation
for additional vegetable crops.
(6) Number of test organisms and replicates.
(i) For each species, the minimum number of replicates is six pots per
concentration, with each pot containing from one to four seedlings. If techniques
other than radioisotopes are used to determine uptake, more replicates may be
needed to provide sufficient plant materials for analysis. The number of seedlings
per replicate depends on the species tested, the size of the containers, and the size
to which the plants will grow. When plants are grown hydroponically, one plant
per pot will probably be the preferred method. The number of plants selected
should provide sufficient biomass for analytical procedures. A greater number of
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plants may be required depending on species tested, duration of test, and
analytical procedures. Too many plants in a container may actually reduce the
growth and biomass; therefore, more replicate pots rather than increasing plants
per pot may be required to obtain sufficient biomass.
(ii) A randomized complete block design is recommended for this test, with
blocks delineated within the growth chambers or over greenhouse benches and
randomization of treatments occurring within the blocks. If there exists
inadequate space within chambers for blocking because of very large pots and
plants, total randomization within chambers is acceptable. This design is also
appropriate for the growth of plants to be used for foliar exposure with gas. To
minimize spatial differences, which can have a significant impact upon plant
growth, the placement of replicates should be randomized during the test (at least
every three to five days).
(iii) Alternative placement should be used with volatile test substances to prevent
cross contamination. For example, in a greenhouse setting use positive air flow
throughout the duration of the study with placement of controls and treatment
levels such that air flows first across controls and then from the lowest treatment
to the highest treatment. In addition, include another set of replicate controls
which are placed in a separate greenhouse for comparison with control results
from the greenhouse containing the treatments. Where tests are conducted using
growth chambers where positive air flow can not be achieved, the controls and
each treatment level should be placed in separate growth chambers.
(7) Facilities, apparatus and supplies—
(i) Greenhouse, environmental chamber, or growth room. Greenhouses,
environmental chambers, or growth rooms should provide adequate
environmental controls to meet the carbon dioxide, humidity, irradiation,
photoperiod, and temperature specifications. Chambers should be designed to
prevent escape of internal air into the external environment other than through
appropriate filtering material or media to prevent contamination of the external
environment with radioactivity and/or test substances. Environmental chambers
and growth rooms are preferred over greenhouses because in the first two,
environmental conditions are more easily controlled.
(ii) Test containers. Test containers should be nonporous so that the test
substance is not absorbed or does not react in any way with the container. Glass
or stainless steel containers with drainage holes can be used as plant pots.
Polyethylene pots that have not been previously used are acceptable test
containers, provided they are free of toxic materials. Do not use clay or peat
containers. For a satisfactory test, pots sufficiently large to grow (e.g., large
enough to effectively not result in competition among the plants for space,
lighting, or nutrition) the desired number of test plants for at least 28 days or up to
maturity. It is equally acceptable to use small, individual containers if plants are
grown in hydroponic solution. Potting containers used in each experiment should
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be of equal size and volume and possess the same configuration. Potting
containers should be covered with opaque polyethylene bags to exclude light and
minimize volatilization of test chemical.
(iii) Cleaning and disposal.
(A) Potting and receiving containers, nutrient storage containers, and root
support medium should be cleaned before use. All equipment should be
washed to remove any residues remaining from manufacturing or use.
Bichromate solution should not be used for cleaning beads or pots.
(B) Quartz sand rooting medium, but not glass beads, should be discarded
at the end of the experiment. Disposal should conform to existing
regulations. Glass beads can be re-used provided they are not
contaminated with previous test substances.
(iv) Support medium.
(A) For tests with industrial chemicals, an artificial support medium,
consisting of quartz sand or glass beads, is used. Alternatively, a
hydroponic system may be used, in which seeds are planted in plugs of
cotton or glass wool supported at the top of the solution. Perlite,
vermiculite, natural (native) soils, or any formulated soils should not be
used as root support medium in this test. Additional information is found
in the OCSPP 850.4320 guideline.
(B) For tests with pesticides, a natural soil (free of chemical
contamination) or a synthetic soil may be used. Additional information on
natural and synthetic soil is found in the OCSPP 850.4100 and OCSPP
850.4150 guidelines.
(v) Nutrient media. A nutrient solution of defined chemical composition, such
as half-strength modified Hoagland nutrient solution (see the reference in
paragraph (j)(5) of this guideline), should be utilized as nutrient medium for this
test. Hydroponic solutions should be aerated and sand or glass filled potting
containers should be periodically filled with nutrient solution and drained to
provide aeration. For root exposure tests, the test substance should be added to
the nutrient solution or directly to substrate. The entire test solution should be
replaced weekly or earlier if the concentration of test substance in the test or
nutrient solution varies by more than 20% of that specified. The volume of
solution added should be recorded. An automated system design is
recommended. For tests with pesticides, any commonly recommended fertilizer
can be added to the soil at recommended rates.
(8) Environmental conditions. Controlled environmental conditions are necessary to
maintain uniform growth and ensure reliable data. Standardization of environmental
conditions is essential because it has been demonstrated that differences in environmental
conditions influence the response of plants exposed to chemicals. For growth chamber
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studies, the general conditions listed in paragraphs (e)(8)(i) through (e)(8)(v) of this
guideline should be maintained. If greenhouses or large growth rooms are used,
comparability of the environment between small groups of plants is not as critical and
environmental variability specifications may be relaxed on a case-by-case basis.
(i) Temperature. Air temperature should be uniform throughout the greenhouse
or growth chamber or greenhouse. In growth chambers air temperature during the
day should be 25 ± 3 °C while temperature during the night should be 20 ± 3 °C.
Temperature in greenhouses is more difficult to control. Under these
circumstances, temperature during the day should be 25 ± 6 °C while temperature
during the night should be 20 ± 6 °C.
(ii) Humidity. Humidity should be uniform throughout the greenhouse or growth
chamber or greenhouse. In growth chambers relative humidity should approach
70 ± 5% during light periods and 90 ± 5% during dark periods. Humidity in
greenhouses is more difficult to control. Under these circumstances, relative
humidity should approach 70 ± 15% during light periods.
(iii) Lighting and photoperiod. Luminance of 350 micromoles per square meter
per second (|imol/m2/s), measured at the top of the canopy, is desirable. Artificial
lighting may be used to lengthen short-day periods or to supplement natural
sunlight on overcast days. A photoperiod of 16 hours light and 8 hours darkness,
assuming an average wavelength of 400 to 700 nanometers (nm), should be used
for all species except soybean which should be provided with 11 hours light and
13 hours darkness prior to flowering.
(iv) Watering. Nutrient media (containing test substance, if this is the selected
application route) is used to subirrigate the plants, i.e., frequent enough to
maintain good health (should not see nutrition deficiency in controls) and
moisture. Pots should be irrigated regularly (for example, 30 minutes per hour
(min/h)) with nutrient solution, for example using a system in which water flows
from the bottom of the pot upward (level should reach at least half way up the
pot). An automatic system design is recommended such as the one described in
the OCSPP 850.4600 guideline. For soil applications, top watering is used at the
first watering after the test substance has been applied to initiate the capillary
movement of water for bottom watering (subirrigation).
(v) Carbon dioxide. Carbon dioxide concentration at 350 ± 50 parts per million
(ppm) (678 + 97 milligrams per cubic meter (mg/m3) of air).
(9) Observations—
(i) Measurement of test substance. For a satisfactory test, analytical
confirmation of the concentration of test substance in the vehicle used to expose
the plants (nutrient medium, glass beads or sand, spray, dust or gas) should be
performed. Additionally, analytical confirmation of the amount of test substance
in plant tissues is determined at test termination as discussed in (e)(9)(iv)(A) of
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this guideline. Analytical methods, validated before test initiation, are used to
measure the amount of test substance in a sample matrix, as described in the
OCSPP 850.4000 guideline.
(A) Nutrient solution. Where test substance was introduced by addition
to the nutrient medium, chemical analysis should be conducted at a
minimum for each treatment level and controls at test initiation (0-hour) in
the bulk solutions and test termination in at least three replicates per
treatment and controls at test termination when nutrient solutions are not
renewed. Where nutrient solution is renewed during the study, chemical
analysis should be conducted at a minimum for each treatment level and
controls at test initiation (0-hour) in the bulk solutions and at the end of
this first cycle in the used nutrient solution, at the beginning (fresh
solution) and end (used solution) of the longest renewal cycle and the last
renewal cycle. It is also recommended that measurements be made at the
beginning of each renewal cycle.
(B) Quartz sand or glass bead support medium. Where test substance
was introduced by addition to the quartz sand or glass bead support
medium, chemical analysis should be conducted at a minimum in the bulk
support medium for each treatment level and control at test initiation and
from at least three pots for each treatment level and control at test
termination.
(C) Foliar spray. Where test substance is applied by foliar spray and a
single batch of test solution for each treatment level and control is used
throughout the study, chemical analysis in the spray solutions should be
conducted at a minimum at test initiation and termination for each
treatment level and control batch. If one or more spray solution batches
are prepared during the study, chemical analysis of spray solutions should
be conducted at a minimum for each treatment level and controls at test
initiation (0-hour) and at the end of the use of this nutrient solution batch,
at the beginning (fresh solution) and end (used solution) of the longest
time between batches and the last batch. It is also recommended that
measurements be made at the beginning of each batch.
(D) Foliar dusting. The amount of test substance to be applied to a
replicate should be weighed prior to application and the weight recorded.
The sleeve placed around the pot during application should be weighed
before and after application if there will be difficulties expected with test
substance not landing in the pot or on the plants or remaining on the
sleeve.
(E) Gas application. For the gas exposure system, at the time of
fumigation the air temperature, dew point temperature or water vapor
pressure of incoming and outgoing air streams, air speed within chamber,
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carbon dioxide concentration at inflow and outflow ports, and gas flow
rate into and out of exposure system are measured and recorded.
(ii) Environmental conditions—
(A) Temperature and humidity. The air temperature and humidity
during the study should be recorded continuously in growth chambers, but
alternatively as maximum and minimum values over each 24-hour period,
especially in greenhouses at representative locations throughout the area in
which the test plants are growing.
(B) Carbon dioxide. In environmental chambers, carbon dioxide
measurements should be made at the top of the plant canopy, preferably
on a continuous basis.
(C) Light intensity. Light intensity should be determined daily at
representative locations throughout the area in which the test plants are
growing, and should be measured at the top of the foliage. A
photosynthetically active radiation (PAR) sensor should be used to
measure light quality. Additional information on the use of lighting in
plant toxicity tests can be found in the references given in the OCSPP
850.4000 guideline.
(D) Watering and evapotranspiration. The amount of nutrient solution
depleted each week should be recorded, to observe changes in
evapotranspiration rates which may indicate stress. Furthermore, these
data will be used to compute chemical uptake per volume of water
transpired for the uptake test.
(E) Pests. Daily observations should be made on pest pressure using an
index of the extent of infestation. Pest infestation may affect the
interpretation of study results and therefore should be adequately
described. Frequency, methods, and rates used for treating an insect or
disease should be recorded.
(F) Nutrient media pH. The pH of nutrient solutions are measured prior
to use in bulk solutions and in used solutions at test termination in each
replicate. If more than one batch of nutrient solution is used throughout
the study the pH of each nutrient solution treatment concentration and
control(s) are measured in the nutrient solution batch prior to use, and at
replacement in the used solution.
(iii) Appearance and condition. Plants are observed on a weekly basis for any
abnormalities and phytotoxic symptoms. All abnormalities (visible effects
including stunting of growth, discoloration, chlorosis and/or necrosis of the
leaves, decreased moisture content, or morphological abnormalities, etc) should
be recorded. Uniform scoring procedures should be used to evaluate any
observable toxic response. Observations should include the treatment level and
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replicate, stage of development and dates when adverse results occurred, subsided
or recovered, and counts for each plant affected. Any lack of effects by the test
substance should also be recorded. Observations of plants should be made at least
once every seven days.
(iv) Uptake and translocation. When sufficient plant biomass for analysis has
been obtained, or when fruits or seeds are mature, the plants are harvested and the
various plant organs are analyzed to establish the mass balance of the test
substance. Carrot, lettuce, onion, cabbage, and ryegrass may be harvested
whenever there is adequate plant material for chemical analysis. Cucumber, corn,
soybean, tomato, and oats should be grown until fruit or seed are mature. An
alternative method can be used for the gaseous exposure system, where direct
calculation of uptake rates can be made based upon measurements of
photosynthesis, transpiration and stomatal conductance, obviating the need for
chemical analysis of the plant tissues.
(A) Plant residue measurements—
(1) Preparation of plant material. The entire plant should be
harvested, rinsed with a minimum amount of reagent water (which
is returned to the nutrient solution), and separated into its
respective organs as follows: carrot—root peels, peeled roots, and
tops; cucumber—fruit, vines plus leaves, and roots; corn—kernels,
husk plus cob, stalk plus leaves, and roots; lettuce—tops and roots;
onion—bulb and tops; ryegrass—tops and roots; soybean—grain,
chaff plus tops, and roots; oats—grain, chaff plus tops, and roots;
tomato—fruit, vines, and roots; cabbage—head and roots. Plants
from two pots in each treatment may be pooled, giving three
replicate sample pools per treatment.
(a) Fresh weight, dry weight, and percent moisture.
After the fresh weights of the plant organs are obtained,
they should be subsampled for percent moisture
determinations by drying, at 70 degrees Celsius (°C) for 24
hours in a forced-air drying oven, and weighing. Percent
moisture determined from these subsamples is used to
correct for dry weight of the fresh samples.
(b) Extraction. Each sample is then homogenized and
extracted in organic and aqueous solvents. A suggested
extraction procedure appropriate for many organic
chemicals is as follows: plant material (1 gram (g)) is
homogenized with 1 g of solvent-washed anhydrous
sodium sulfate in 4 milliliters (mL) of hexane or
acetonitrile. The homogenate is then filtered or
centrifuged, the solid residue rinsed with an appropriate
organic solvent, and the filtrate or supernatant combined
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with the rinse. The solid residue should be extracted by
sequentially (one) homogenizing in water, (two)
centrifuging and decanting the supernatant, (three)
extracting of the pellet with 6 Normal (N) hydrochloric acid
at 60 °C for 10 hours, (four) subsequently digesting with 10
TV potassium hydroxide, and (five) combining supernatants.
(2) Analytical methods. If radioisotopes are used, the amount of
test substance in each extract should be determined by liquid or
solid scintillation; otherwise, the amount of test substance should
be determined by standard methods. The organic extract should be
evaporated under vacuum to a sufficiently small volume for thin
layer chromatography (TLC) and co-chromatographed on silica gel
plates with known standards of the parent test substance. If
radioisotopes were used, the chromatographs could be scanned for
radioactive substances on a radiochromatogram scanner.
Alternatively, zones may be removed from the plates, extracted,
and the quantity of test substance from each zone determined by
liquid scintillation spectrometry or gas liquid chromatography
(GLC) methodology. The unextractable test substance in the
remaining residue may be determined by oxidizing the residue in a
complete combustion oxidizer.
(B) Gaseous test substances—
(1) Direct calculation of uptake rates. A gas exposure system
yields requisite data for a direct calculation of uptake rates. At
steady state, test substance uptake may be determined by a mass
balance calculation. Correction for adsorption to surfaces of the
exposure chamber should be made by operating the system without
plants. Pots filled with hydroponic solution or support media
should be included in the system adsorption calibration.
Consequently, chemical analysis of plant tissues exposed to
gaseous chemicals may not be required in order to demonstrate and
quantitate uptake rates.
(2) Physiological rates. Altered rates of net photosynthesis,
transpiration, and stomatal conductance are anticipated as a result
of test substance uptake. Rates of these physiological processes
before, during, and after exposure to the gaseous chemical should
be determined. Data required for these calculations are available
as a consequence of maintaining the specified environmental
conditions within the fumigation chamber.
(3) Plant surface area mass measurements. For each pot
measure the plant surface area mass.
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(C) Root support medium measurements. At test completion, the root
support material should be washed in organic and then aqueous solvent
and analyzed for test substance before discarding.
(f) Treatment of results—
(1) Data summary—
(i) For liquid and solid test substances.
(A) Means and standard deviations of the fresh weight and dry weight
mass of plant organs and by summation, the mass of the whole plant are
calculated for each treatment (includes controls).
(B) Means and standard deviations of the concentration of free parent test
substance, metabolites and soluble residues, and bound residues in plant
organs and whole plants by treatment. Concentrations should be
expressed in appropriate weight units per grams of dry plant material.
(C) Mean evapotranspiration rate per plant.
(D) Initial and final total concentration of the test substance (total
residues: parents plus degradates) in the support media.
(E) Mean and standard deviations of the mass balance of test substance by
treatment.
(ii) For gaseous test substances.
(A) Measurements as described in paragraphs (f)(l)(i)(A) through
(f)(l)(i)(E) of this guideline for solid and liquid test substances;
alternatively, the measurements described in paragraphs (f)(l)(ii)(B)
through (f)(l)(ii)(D) of this guideline.
(B) Mass of leaves and stems and surface area (one side of leaves) in the
exposure system.
(C) Steady state rates of photosynthesis, transpiration, and test substance
uptake before, during, and after fumigation.
(D) Stomatal conductance or leaf diffusion resistance before, during, and
after fumigation.
(2) Definitive test. Mass balance of the test substance and evapotranspiration rate of the
plants is subjected to analysis of variance. An analysis of variance, followed by a means
separation test, is performed to determine which test substance treatments resulted in
residues from uptake/translocation or evapotranspiration rates that are significantly
different from those in the control(s).
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(g) Tabular summary of test conditions. Table 2 lists the important conditions that should
prevail during the definitive test. Meeting these test conditions will greatly increase the
likelihood that the completed test will be acceptable or valid. These test conditions apply mainly
to growth chambers and growth rooms; they are preferred to greenhouses where for the latter it
may be more difficult to meet or control these conditions.Table 2.—Summary of Test
Conditions for Plant Uptake and Translocation Test1
Test duration
Substrate
Nutrients
Temperature
Relative humidity
Carbon dioxide
Light quality
Light intensity
Photoperiod
Watering
Test chamber (pot) size
Number of organisms per test
chamber
Number of replicate chambers per
test treatment
Number of organisms per test
treatment
Test treatment levels
Test substance application method
Measures of effect (Measurement
endpoints)
To provide sufficient biomass (or to allow gas exchange
measurements), or until fruit or seeds are mature.
Quartz sand or glass beads. Hydroponic system may also be
used. (For pesticides, natural or synthetic soil may also be used.)
Watered with nutrient solution (half-strength modified Hoagland's
medium)
25/20 °C (daytime/nighttime) ± 3 °C (applicable to growth
chambers)
70/90% (daytime/nighttime) ± 5% (applicable to growth chambers)
350 ± 50 ppm (applicable to growth chambers)
Fluorescent or representative of natural sunlight
350 ± 50 umol/m2/sec
16 hours light: 8 hours dark for all species except soybean with 1 1
hours light: 13 hours dark prior to flowering
Bottom watering as needed, using nutrient solution
Varies with plant species selected.
Typically, 1 - 4 seedlings of one species per pot
6 (minimum)
6 - 24 (minimum)
Minimum of 3 treatment levels plus appropriate controls
Root exposure (via watering with nutrient solution or sorbed onto
the substrate) or foliar exposure (via spray, dust or gas) or soil
surface exposure.
Mass balance on test substance, including concentrations of free
parent test substance, metabolites and soluble residues, and
bound residues in plant organs and whole plants. (Alternatively, for
gaseous test substances, measurements of photosynthesis,
transpiration, and stomatal conductance, and mass of plant surface
area).
Constraints on environmental conditions are mainly applicable to growth chamber studies
(h) Test validity elements. This test would be considered to be unacceptable or invalid if one or
more of the conditions in Table 3 did not occur or one or more performance objectives in Table 3
were not met. This list should not be misconstrued as limiting the reason(s) that a test could be
found unacceptable or invalid. However, except for the conditions listed in Table 3 and in the
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OCSPP 850.4000 guideline, it is unlikely a study will be rejected when there are slight variations
from guideline environmental conditions and study design unless the control organisms are
significantly affected, the precision of the test is reduced, the power of a test to detect differences
is reduced, and/or significant biases are introduced in defining the magnitude of effect on
measurement endpoints as compared to guideline conditions. Before departing significantly
from this guideline, the investigator should contact the Agency to discuss the reason for the
departure and the effect the change(s) will have on test acceptability. In the report, all departures
from the guideline should be identified, reasons for these changes given, and any resulting
effects on test endpoints noted and discussed.
Table 3.—Test validity elements for the plant uptake and translocation test
1. For any species, all organisms in a test are from the same source.
2. All test chambers used for a particular species are identical and contain the same amount of substrate
from the same source.
3. An untreated (or negative) control [and solvent (or vehicle) control, when a solvent was used] is
included in the test.
4. Seed germination percentage in each of the controls is at least 65% for the recommended test species;
or the minimum acceptable USDA seed germination standards listed in paragraph (e)(5)(ii)(B) of this
guideline. For native species that do not have germination standards, sufficient numbers of seeds, are
used to provide statistically valid measures of effect.
5. There are no signs of stress from competition or crowding of plants.
(i) Reporting—
(1) Background information. Background information to be supplied in the report
consists at a minimum of those background information items listed in paragraph (j)0) of
the OCSPP 850.4000 guideline.
(2) Guideline deviations. Provide a statement of the guideline or protocol followed.
Include a description of any deviations from the test guideline or any occurrences which
may have influenced the results of the test.
(3) Test substance.
(i) Identification of the test substance: common name, IUPAC and CAS names,
CAS number, structural formula, source, lot or batch number, chemical state or
form of the test substance, and its purity (i.e. for pesticides, the identity and
concentration of active ingredient(s)), radiolabeling if any, location of label(s),
and radiopurity.
(ii) Storage conditions of the test chemical or test substance and stability of the
test chemical or test substance under storage conditions if stored prior to use.
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(iii) Methods of preparation of the test substance and the treatment doses used in
the range-finding and definitive test.
(iv) If a vehicle (e.g., solvent, dust) is used to prepare stock or test substance
provide: the name and source of the vehicle, the nominal concentration(s) of the
test substance in the vehicle in stock solutions or mixtures, and the vehicle dose(s)
used in the treatments.
(4) Plant test species.
(i) Scientific and common name, plant family, and variety.
(ii) Test date of germination rating and determining percent germination.
(iii) History of the seed: source, name of supplier, seed year or growing season
collected, batch or lot number, seed treatment(s), and storage conditions.
(iv) Seed size class.
(v) Description of handling and processing of seeds, pre-test planting, production,
and handling of test seedlings before use in test.
(vi) Height and condition of seedlings selected for the test.
(5) Test system and conditions. Description of the test system and conditions used in
the definitive test, and any preliminary range-finding tests.
(i) A description of the test system, including type of growth chamber, growth
room, or greenhouse.
(ii) The description of pots or test containers: type, material, dimensions.
(iii) Number of seedling plants per pot or test container.
(iv) Number of pots per replicate, and number of replicates per treatment level.
(v) Description of the support medium or hydroponic system: source, type,
material.
(vi) Volume of support medium per pot or test container.
(vii) Methods used for treatment randomization.
(viii) Methods for preparing the test treatments: exposure route (root or foliar
exposure), application methods (including equipment type and method for
calibrating the application equipment), information about any solvent used to
dissolve and apply the test substance, and the concentrations (concentration of the
test substance in nutrient solution or in the foliar application vehicle, or the
quantity of test substance per unit weight of root support material when it is
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coated on the support material, the concentration of test substance applied to the
soil surface; the concentration of test substance in the dust or spray; or the
concentration of gaseous test substances at inflow and outflow ports) and the
amounts used.
(ix) The method for calibrating the application equipment.
(x) Number of applications and dates applied.
(xi) Culture practices during the test such as pest control, and irrigation practices
(type and watering schedule or regime).
(xii) The photoperiod and light source.
(xiii) Methods and frequency of environmental monitoring performed during the
definitive test for air temperature, humidity, and light intensity.
(xiv) For the definitive test, all analytical procedures should be described. The
accuracy of the method, method detection limit, and limit of quantification should
be given.
(6) Results.
(i) Environmental monitoring data results (carbon dioxide concentrations, air
temperature, humidity and light intensity) in tabular form (provide raw data for
measurements not made on a continuous basis), and descriptive statistics (mean,
standard deviation, minimum, maximum).
(ii) Tabulation of the watering schedule, the volume of nutrient solution (or
hydroponic solution) used and depleted each week by replicate within a treatment
and control and the evapotranspiration rates calculated from the data.
(iii) For the gas exposure system, tabular summary of the air temperature, dew
point temperature or water vapor pressure of incoming and outgoing air streams,
air speed within chamber, carbon dioxide concentration at inflow and outflow
ports, and gas flow rate into and out of exposure system (provide raw data for
measurements not made on a continuous basis).
(iv) For the definitive test, a description of visual (morphological) signs of
phytotoxicity including: time of onset, duration, severity (e.g. rank), and number
affected at each dose level and control(s) (provide the raw data). A description of
the phytotoxicity rating system used should be included.
(v) For the definitive test, tabulation of the fresh weight, dry weight, and percent
moisture of plant organs (e.g., carrot—root peels, peeled roots, and tops;
cucumber—fruit, vines plus leaves, and roots; oats—grain, chaff plus tops, and
roots) by replicate and treatment (provide the raw data). For gaseous test
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substances, in addition to or in lieu of these measurements, tabulation of the plant
surface area mass by replicate and treatment.
(vi) For the definitive test, tabulation of the concentrations of parent test
substance, metabolites, soluble residues and bound residues in plant organs and
whole plants by replicate (pooled replicate, if applicable) and treatment. For
gaseous test substances, in addition to or in lieu of these measurements, tabulation
of the calculated measurements of photosynthesis, transpiration, and stomatal
conductance before, during, and after exposure to test chemicals by replicate and
treatment (provide raw data).
(vii) For the definitive test, tabulation of the mass balance of test substance by
replicate and treatment.
(viii) For the definitive test, means and standard deviations of mass balance of test
substance by treatment.
(ix) For the definitive test, plots of the means and standard deviations of mass
balance of test substance by treatment.
(x) For the definitive test, analysis of variance, F-test, means, and standard
deviation about the mean for the measured endpoints.
(xi) Methods of statistical analyses, including software used, should be reported.
(j) References. The references in this paragraph should be consulted for additional background
material on this test guideline.
(1) American Society for Testing and Materials. ASTM E 1963-02. Standard guide for
conducting terrestrial plant toxicity tests. In Annual Book of ASTM Standards, Vol.
11.06, ASTM, West Conshohocken, PA. Current edition approved December 10, 2002.
(2) Beall, M.L., Jr. and Nash, R.G. 1969. Crop seedling uptake of DDT, dieldrin, endrin,
and heptachlor from soil. Agronomy Journal 61:571-575.
(3) Bennett, J.H., Hill, C., and Gates, D.M. 1973. A model for gaseous pollutant
sorption by leaves. Journal of the Air Pollution Control Association 23:957-962.
(4) Chou, S.F., Jacobs, L.W., Penner, D., and Tiedje, J.M. 1978. Absence of plant
uptake and translocation of polybrominated biphenyls (PBBs). Environmental Health
Perspectives 23:9-12
(5) Cole, L.K., Sanborn, J.R., and Metcalf, R.L. 1976. Inhibition of corn growth by
aldrin and the insecticide's fate in the soil, air, crop, and wildlife of a terrestrial model
ecosystem. Environmental Entomology 5:583-589.
(6) Downs, R.J. 1975. Controlled Environments for Plant Research. Columbia Univ.
Press, NY.
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(7) Downs, RJ. and Helmers, H. 1975. Environment and Environmental Control of
Plant Growth. Academic Press, NY.
(8) Fuhr, F. and Mittelstaedt, W. 1980. Plant experiments on the bioavailability of
unextracted (carbonyl-14C) methabenzthiazuron residue from soil. Journal of
Agriculture and Food Chemistry 28:122-125.
(9) Hatzios, K.K. and D. Penner. 1985. Interactions of herbicides with other
agrochemicals in higher plants. Rev. Weed Sci. 1:1-63.
(10) Kelly, J.M., Parker, G.R., and McFee, W.W. 1980. Heavy metal accumulation and
growth of seedlings of five forest species as influenced by soil cadmium level. Journal of
Environmental Quality 8:361-364. [
(11) Tibbits, T.W. and Kozlowski, T.T. (eds.). 1979. Controlled Environment
Guidelines for Plant Research. Academic Press, NY
(12) Wickliff, C., Evans, H.J., Carter, K.R. and Russell, S.A., 1980. Cadmium effects on
the nitrogen fixation system of red alder. Journal of Environmental Quality 9:180-184.
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