| MatrixName | MatrixDescr |
| air | colorless, odorless, tasteless, gaseous mixture, mainly nitrogen (approximately 78 percent) and oxygen (approximately 21 percent) with lesser amounts of argon, carbon dioxide, hydrogen, neon, helium, and other gases |
| benthic | Flora and fauna collected from the bottom of a waterbody |
| blankmatrix | matrix free of interferences (e.g, in reagent water, clean sand, or another suitable reference matrix) that is commercially or Lab-produced used for tissue and sediment QA samples |
| blankwater | matrix free of interferences (reagent water) that is commercially or Lab-processed used for water QA sample |
| effluent | Wastewater--treated or untreated--that flows out of a treatment plant, sewer, or industrial outfall |
| Extract_AlgalMat | Algal mat sample digested/extracted by laboratory procedure |
| Extract_Samplewater | Samplewater extracted from sorbent media or solid phase extraction |
| groundwater | The supply of fresh water found beneath the Earth's surface, usually in aquifers, which supply wells and springs |
| habitat | habitat at the location |
| labwater | unprocessed laboratory tap water |
| Not Applicable | not applicable |
| not recorded | not recorded |
| overlyingwater | the water above the sediment surface within a test container, used for toxicity |
| PBSwater | Phosphate buffered saline |
| PCRmatrix | Used for QC samples in PCR analyses. PCR reagents without the addition of sample DNA or a positive standard. May contain PCR Extraction Blank. |
| referencetoxicant | metal or chlorinated organic used to evaluate the health and sensitivity of test organisms over time and assessing laboratory performance |
| runoff | That part of precipitation, snow melt, or irrigation water that runs off the land into streams or other surface-water. Water sampled prior to mixing with ambient surface water. |
| samplewater | Ambient surface water collected in the field |
| samplewater, <1.2 um | Samplewater filtered through <1.2 um |
| samplewater, <125 um | Samplewater filtered through <125 um |
| samplewater, <200 um | Samplewater filtered through <200 um |
| samplewater, <35 um | Samplewater filtered through <35 um |
| samplewater, <5 um | Samplewater filtered through <5 um |
| samplewater, particulate, <177 um | Particulate from samplewater filtered through <177 um |
| samplewater, particulate, <63 um | Particulate from samplewater filtered through <63 um |
| samplewater, particulate, >200 um | Particulate from samplewater filtered through >200 um |
| samplewater, particulate, 1.2 to <5 um | Particulate from samplewater filtered through 1.2 to <5 um |
| samplewater, particulate, 125 to <200 um | Particulate from samplewater filtered through 125 to <200 um |
| samplewater, particulate, 35 to <125 um | Particulate from samplewater filtered through 35 to <125 um |
| samplewater, particulate, 5 to <35 um | Particulate from samplewater filtered through 5 to <35 um |
| samplewater, particulate, 63 um to 2000 um | Particulate from samplewater filtered through 63 um to 2000 um |
| sediment | Loose particles of sand, clay, silt, and other substances that settle at the bottom of a water body |
| sediment, <63 um | Sediment sample sieved through <63 um |
| sediment, 63 to 2000 um | Sediment sample sieved through 63 to 2000 um |
| sediment, elutriate | Sediment, elutriate - Non-contaminated water mixed with sediment and allowed to settle prior to analysis of the water portion |
| sediment, interstitialwater | water occupying the spaces between sediment particles- same as pore water - may or may not be centrifuged |
| sedimentsuspended | Sediment sample isolated from large volumes of water by centrifuging |
| SEM-Extract | Extract derived from the Simultaneously Extracted Metals procedure, analyzed for individual metal concentrations. |
| tissue | Part of an organism consisting of an aggregate of cells having similar function; muscle, nerve epidermal or connective |
| unknown | matrix is not known |