API TR 402:1995 pdf download.Toxicity to the Freshwater Alga, Selenastrum capricornutum
The objective of this study was to determine the effect of Tert-Amyl Methyl Ether (TAME) on the growth of the freshwater alga Selenastrum capricornutum. The exposure system was specifically modified to minimize the loss of test material due to volatilization. The resuits are based on mean measured concentrations and are reported as the 96-hour EC10, EC50 and EC90 values (i.e., the concentrations of test material that reduce culture density by 10, 50 and 90%, respectively, as compared with the control). The study was initiated on 16 October 1992, the day the Study Director signed the protocol, and was completed on the day the Study Director signed the final report. The experimental phase of the 96-hour acute toxicity test was conducted from 18to 22 November 1993 at the Environmental Sciences Division of Springborn Laboratories, Inc. (SLI), Wareham, Massachusetts. A final report for this study was isued to American Petroleum Institute dated 24 February 1994. This amended final report, 12 August 1994, incorporates changes as made in Final Report Amendment #1.
2.3 Test Organism
The alga used in this toxicity test was the freshwater green alga Selenastrum capricornutum, strain 1648, class Chlorophyceae. The alga was originaly obtained from the Carolina Biological Supply Company, Burlington, North Carolina, and was maintained in stock culture at Springborn. The culture medium used was Algal Assay Procedure (AAP) medium prepared with sterile, deionized water. The components used to formulate the AAP medium are presented in Table 1. Representative samples of the water source used to prepare the deionized water for AAP medium preparation were analyzed for the presence of pesticides, PCBs and toxic metals (Appendix II). None of these compounds have been detected at concentrations that are considered toxic in any of the water samples analyzed in agreement with U.S. EPA guidelines. In addition, a representative sample of AAP medium is analyzed monthly for total organic carbon (TOC) concentration. The TOC concentration of the AAP medium was 0.90 mg/L for the month of November 1993.
2.4 Test Dilution Water
The AAP medium used to prepare the exposure solutions during the preliminary and definitive tests was formulated in the same manner as the culture medium except 500 mg/L sodium bicarbonate was added切the medium to provide sufficient sodium bicarbonate for cell growth in a closed test system. Several liters of test medium were prepared and equlibrated to test temperature. The initial pH of this medium was 8.1 and was adjusted to 7.6 with 0.1 N HCI prior to use.