1、Designation: E1197 87 (Reapproved 2004) E1197 12Standard Guide forConducting a Terrestrial Soil-Core Microcosm Test1This standard is issued under the fixed designation E1197; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year
2、 of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide defines the requirements and procedures for using soil-core microcosms to test the environmental fate,
3、ecologicaleffects, and environmental transport of chemicals that may enter terrestrial ecosystems. The approach and the materials suggestedfor use in the microcosm test are also described.1.2 This guide details a procedure designed to supply site-specific or possibly regional information on the prob
4、able chemicalfate and ecological effects in a soil system resulting from the release or spillage of chemicals into the environment in either liquidor solid form.1.3 Experience has shown that microcosms are most helpful in the assessment process after preliminary knowledge about thechemical propertie
5、s and biological activity have been obtained. Data generated from the test can then be used to compare thepotential terrestrial environmental hazards of a chemical.1.4 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibilityof th
6、e user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D422 Test Method for Particle-Size Analysis of SoilsD511 Test Methods for Calcium and Magnesium In WaterD515 T
7、est Method for Phosphorus In Water (Withdrawn 1997)3D1426 Test Methods for Ammonia Nitrogen In WaterD2167 Test Method for Density and Unit Weight of Soil in Place by the Rubber Balloon MethodD2216 Test Methods for Laboratory Determination of Water (Moisture) Content of Soil and Rock by MassD2488 Pra
8、ctice for Description and Identification of Soils (Visual-Manual Procedure)D3867 Test Methods for Nitrite-Nitrate in Water2.2 U.S. Environmental Protection Agency:Environmental Effects Test Guidelines, EPA 560/6-82-002, 19824Chemical Fate Test Guideline, EPA 560/6-82-003, 198253. Terminology3.1 Defi
9、nitions:1 This guide is under the jurisdiction of ASTM Committee E47 on Biological Effects and Environmental Fateand is the direct responsibility of Subcommittee E47.02 onTerrestrial Assessment and Toxicology.Current edition approved Aug. 1, 2004Nov. 1, 2012. Published August 2004December 2012. Orgi
10、nallyOriginally approved in 1987. Last previous edition approved in19982004 as E119787(1998).E119787(2004). DOI: 10.1520/E1197-87R04.2 For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume inf
11、ormation, refer to the standards Document Summary page on the ASTM website.3 The last approved version of this historical standard is referenced on www.astm.org.4 Available from the Office of Pesticides and Toxic Substances, Washington, DC. Also available as PB82 23992 from National Technical Inform
12、ation Service (NTIS),United States Department of Commerce, 5285 Port Royal Rd., Spring-field, VA 22161.5 Available from Office of Pesticides and Toxic Substances, Washington, DC. Also available as PB82 233008 from National Technical Information Service (NTIS),United States Department of Commerce, 52
13、85 Port Royal Rd., Spring-field, VA 22161.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, AS
14、TM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.1.1
15、soil-core terrestrial microcosman intact soil-core containing the natural assemblages of biota surrounded by theboundary material. The system includes all equipment, facilities, and instrumentation necessary to maintain, monitor, and controlthe environment.3.2 Definitions of Terms Specific to This S
16、tandard:3.2.1 terrestrial microcosm or micro-ecosystem a physical model of an interacting community of autotrophs, omnivores,herbivores, carnivores and decomposers within an intact soil profile. The forcing functions, for example, light intensity andduration, water quality and watering regime, tempe
17、rature, and toxicant dose for the test system, are under the investigators control.This test system is distinguished from test tube and single-species toxicity tests by the presence of a natural assemblage oforganisms. This assemblage creates a higher order of ecological complexity and, thus, provid
18、es the capacity to evaluate chemicaleffects on component interactions and ecological processes. Certain features of this test system, however, set limits on the typesof questions that can be addressed. Those limitations are related to scale and sampling, which in turn constrain both (a) the typeof e
19、cosystems and species assemblages on which one can gain information, and (b) the longevity of the test system.3.2.2 physical, chemical, and biological conditions of test systemdetermined by the type of ecosystem from which the testsystem was extracted and by either the natural vegetation in the ecos
20、ystem or the crops selected for planting. Vegetation and cropselection are constrained and determined by the size (width and depth) of the soil core extracted.3.2.3 boundariesthe boundaries of the test system are determined by the size of the soil-core and the space needed forvegetative growth.3.2.4
21、 lightlight for the test system can be supplied by artificial means in either a growth chamber or a greenhouse, or it canbe the natural photoperiod occurring in a greenhouse. If the test is performed in a growth chamber, the daily photoperiod shouldbe equal to or greater than the average monthly inc
22、ident radiation (quantity and duration) for the month in which the test is beingsimulated. During extremely short natural photoperiods, which might not allow for flowering or seed-set, photoperiod should beartificially lengthened to induce those responses. The spectral quality of visible light suppl
23、ied during testing should simulate thatof sunlight (for example, include commercially available visible full-spectrum lamps).3.2.5 waterwater for the test system should either be purified, untreated laboratory water or water, should be precollected,filtered rainwater from the site or region being ev
24、aluated. evaluated, or formulated rainwater (for example, based on rainfall of theregion). Chemical characterization of the water, either laboratory or rainwater, is required and must be performed using TestMethods D511, D515, D1426, and D3867.3.2.6 soilthe soil-core used for the microcosm test shou
25、ld be an intact, undisturbed (nonhomogenized) core extracted from asoil type typical of the region or site of interest. The core should be of sufficient depth to allow a full growing season for the naturalvegetation or the crops selected, without causing the plants to become significantly rootbound.
26、 Disturbances during extraction andpreparation should be kept to a minimum. It should be noted that soil characteristics play an important role in how the microcosmresponds to a test substance. In addition, within-site soil heterogeneity also influences the microcosm response and contributes toa los
27、s of sensitivity of the test. The approach used in this test system, however, is based on a comparison of responses among andbetween treatments rather than on the absolute values measured.3.2.7 biotathe biota of the microcosm are characterized by the organisms in the soil at the time of extraction (
28、1, 2)6 and bythe natural vegetation or crops introduced as the autotrophic component. The biota may include all heterotrophic and carnivorousinvertebrates typically found in the soil and all soil and plant microbes.4. Significance and Use4.1 This guide provides a test procedure for evaluating the po
29、tential ecological impacts and environmental transport of achemical in an agricultural (tilled, low-till, or no-till) or natural field soil ecosystem that may be released or spilled into theenvironment. The suggested test procedures are designed to supply site-specific information for a chemical wit
30、hout having toperform field testing. (See EPA 560/6-82-002 and EPA 560/6-82-003.)4.2 This guide is not specifically designed to address fate of chemicals in soils of forested ecosystems. However, with somemodifications, it may be adapted for that purpose by the individual investigator.4.3 Specifical
31、ly, this guide is used to determine the effect of a chemical on (1) growth and reproduction of either naturalgrassland vegetation or crops, and (2) nutrient uptake and cycling within the soil/plant system. Additionally, the soil-coremicrocosm will provide information on (1) potential for bioaccumula
32、tion (enrichment) of the chemical into plant tissues, and (2)the potential for and rate of transport of the chemical through soil to ground water.groundwater.4.4 The results of this test should be used in conjunction with information on the chemical and biological activity of the testsubstance to as
33、sess the relative environmental hazard and the potential for environmental movement once released.6 The boldface numbers in parentheses refer to a list of references at the end of this guide.E1197 1224.5 The test methods described in this guide are designed specifically for liquid or solid materials
34、. Significant modifications ofthe exposure system would be necessary to accommodate chemicals that are volatile or that may be released in a gaseous oraerosolized form. For methods that could be adapted for use with volatile or gaseous test substances see Refs (3, 4, 5, 6).4.6 Results of a multi-yea
35、r soil-core microcosm test have been correlated with data derived from a series of multi-year field plottests for a limited number of materials. Information on the correlation between microcosm and field results can be found in Refs(7, 89, 910, 1011).5. Chemical Characterization of Test Substance an
36、d Soil5.1 Information Required on Test Substance:5.1.1 Minimum information required to properly design and conduct an experiment on a test chemical includes the chemicalsource, composition, degree of purity, nature and quantity of any impurities present, and certain physiochemical information suchas
37、 water solubility and vapor pressure at 25C (1112, 1213). Ideally, the structure of the test chemical should also be known,including functional groups, nature and position of substituting groups, and degree of saturation. The octanol-water-partitioncoefficient, the dissociation constant, the degree
38、of polarity, and the pH of both pure and serial dilutions should also be known.Where mixtures are involved or where a significant impurity (1 %) occurs, data must be available on as many components aspractical. However, the octanol-water-partition coefficient (Kow) stands out as the key value. Soil
39、sorptiona key value for lipophiliccompounds. Soil partition coefficient (Ksd) or sorption constant can be determined or estimated, and organic carbon partitioncoefficient (Koc) can be estimated from log Kow using the organic matter content. Water solubility can be predicted with somedegree of accura
40、cy from log Kow if this value is less than seven. In combination with other chemical characteristics, log Kow canalso be used to estimate Henrys Law Constant and thus provide a rough estimate of the potential volatility of the test substancefrom soil solutions.5.1.2 Several tests may be needed to su
41、pply information on environmental mobility and stability. Support information onphytotoxicity, the physicochemical nature of the chemical, its mammalian toxicity, or its ecological effects (for example,species-specific LC50, invertebrate toxicity, biodegradability) not only assist in proper design o
42、f the microcosm experiment, butalso are useful in assessing the fate and effects of the chemical in a terrestrial microcosm. If the chemical is radioactively labeled,the position and specific element to be labeled should be specified.5.1.3 It is imperative to have an estimate of the test substance t
43、oxicity to mammals as a precaution for occupational safety. Inaddition, hydrolysis or photolysis rate constants should be known in order to determine necessary handling precautions. When aradiolabeled material is used, normal laboratory techniques for radiation safety provide an ample margin of safe
44、ty (1314), exceptfor chemicals in the “very highly toxic” category (rat oral LD50 25 mm Hg) are not suitable for testingin the terrestrial soil-core microcosm described in this guide. According to Refs (6, 1819), modification of the test system shouldbe useful for handling gaseous or aerosolized che
45、micals.5.2 Information Required on Soil:5.2.1 Soil sorption of an organic molecule depends on several properties of the chemical (molecular size, ionic speciation,acid-base properties, polarity, and nature of functional groups) and of the soil (for example, organic matter content, clay content,clay
46、mineralogy and nature, pH, water content, bulk density, cation exchange capacity, and percent base saturation). Highly sorbedchemicals may displace inorganic nutrient ions from exchange sites in the soil and also may be effectively immobilized, dependingon soil pH. Thus, chemicals attracted more str
47、ongly to soil surfaces than to water may be very immobile in soil. In some cases,this may render the compound relatively resistant to biodegradation. In other cases, however, immobilization of the compound onsoil particles may render it susceptible to extracellular enzymatic degradation. Specific in
48、formation on descriptive data requiredfor soil can be found in 6.2.2.6. Terrestrial Microcosm Extraction and Maintenance6.1 Microcosm and CartChamber Design:6.1.1 The A 60-cm deep by 17-cm 10-cm diameter terrestrial soil-core microcosm is designed to yield pertinent informationabout a chemical for e
49、ither a natural grassland ecosystem or an agricultural ecosystem planted with a multiple-species crop (Fig.1) (7, 8, 9, 10, 1920, 2021). The agricultural microcosm is a 10 to 17-cm diameter tube of plastic pipe that is made of ultra-highmolecular weight, high-density, and nonplasticized polyethylene and contains an intact soil core (40 cm) covered by homogenizedE1197 123topsoil (20 cm). The natural grassland microcosm is ( 40 cm) including topsoil. A microcosm for large plants may require an intacttotally undisturbed 17-cm diameter by 60-cm60-cm deep test sy