Maximum acceptable toxicant concentration

The chronic aquatic effects which relate silver speciation to adverse environmental effects were studied on rainbow trout eggs and fry. The maximum acceptable toxicant concentration (MATC) for silver nitrate, as total silver, was reported to be 90—170 ng/L (43). Using fathead minnow eggs and fry, the MATC, as total silver, for silver thiosulfate complexes was reported as 21—44 mg/L, and for silver sulfide as 11 mg/L, the maximum concentration tested (27). 

Maximum acceptable toxicant concentration values (MATC) for toxaphene and aquatic organisms, based on exposure for the entire or most of the life cycle... 

Table 2.5 Maximum Acceptable Toxicant Concentration (MATC) Values for Hexavalent and Trivalent Chromium to Aquatic Life Based on Life Cycle or Partial Life Cycle Exposures... 

The maximum acceptable toxicant concentration (MATC) values calculated for mirex and various freshwater species were ... 

Table 27.3 Maximum Acceptable Toxicant Concentration Values (MATC) for Toxaphene and Aquatic Organisms, Based on Exposure for the Entire or Most of the Life Cycle (Concentrations are in micrograms of toxaphene per liter [ppb].)... 

Maximum acceptable toxicant concentration (MATC) valnes for hexavalent and trivalent chromium to aquatic life based on life cycle or partial life cycle exposures... 

MATC = Maximum acceptable toxicant concentration. Lower value in each MATC pair indicates highest concentration tested producing no measurable effect on growth, survival, reproduction, and metabolism during chronic exposure higher value indicates lowest concentration tested producing a measurable effect. 

The NOEC and the LOEC are the usual calculations reported from chronic toxicity tests. The NOEC is the highest concentration in which the measured effect is not statistically different from that of the control. The LOEC is the lowest concentration at which a statistically significant effect occurred. These concentrations are based on the most sensitive effect parameters, that is, hatchability, growth, and reproduction. The statistical procedure for these calculations combines the use of analysis of variance techniques and multiple comparison tests. In some cases, the maximum acceptable toxic concentration (MATC) is reported from chronic toxicity results. The MATC is a concentration [x) that is within the range of the NOEC and LOEC NOEC a < LOEC. The first-effect concentration can be expressed as the geometric mean of the two terms. 

Maximum acceptable toxicant concentration. MATC is the geometric mean of the LOEC and NOEC and is a commonly used expression of chronic aquatic toxicity Maximum exposure limit... 

Peres I and Phan JC (1991) CopperLC oto Cyprinus carpio. Influence of hardness, seasonal variation, proposition of maximum acceptable toxicant concentration. Environ Technol 12 161-167. 

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