1.1 This practice covers procedures for obtaining data concerning toxicity and other effects of a test material to a multi-trophic level freshwater community.

1.2 These procedures also might be useful for studying the fate of test materials and transformation products, although modifications and additional analytical procedures might be necessary.

1.3 Modification of these procedures might be justified by special needs or circumstances. Although using appropriate procedures is more important than following prescribed procedures, results of tests conducted using unusual procedures are not likely to be comparable to results of many other tests. Comparison of results obtained using modified and unmodified versions of these procedures might provide useful information concerning new concepts and procedures for conducting multi-trophic level tests.

1.4 This practice is arranged as follows:

Referenced Documents- 2

Terminology- 3

Summary of Practice- 4

Significance and Use- 5

Apparatus- 6

Facilities- 6.1

Container- 6.2

Equipment- 6.3

Hazards- 7

Microcosm Components- 8

Medium- 8.1

Medium Preparation- 8.2

Sediment- 8.3

Microcosm Assembly- 8.4

Test Material- 9

General- 9.1

Stock Solution- 9.2

Nutrient Control- 9.3

Test Concentration(s)- 9.4

Test Organisms- 10

Algae- 10.1

Animals-10.2

Specificity of Organisms- 10.3

Sources- 10.4

Algal Culture Maintenance- 10.5

Animal Culture Maintenance- 10.6

Section Procedure- 11

Experimental Design- 11.1

Procedure Inoculation- 11.2

Culling- 11.3

Addition of Test Material- 11.4

Measurements- 11.5

Reinoculations- 11.6

Analytical Methodology- 12

Data Processing- 13

Calculations of Variables from Measurements- 14

Statistical Analyses- 15

Acceptability of Test- 16

Interpretation of Results- 17

Report- 18

Annex- Annex A1

Appendices Relationship of Media- Appendix X1

Statistical Guidance Appendix- X2

1.5 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific hazard statements are given in Section 7.