LAC 51:IX.123. Procedure for the Analysis of Shellfish Growing Waters [formerly paragraph 9:002-11]

A. Analysis of shellfish growing waters for the Louisiana Molluscan Shellfish Program shall be performed by a laboratory officially designated as part of the Louisiana shellfish sanitation laboratory system. Procedures and methods for analysis of shellfish growing water shall conform to criteria stipulated in the 4th edition of American Public Health Association (APHA) Recommended Procedures for the Examination of Sea Water and Shellfish published August 29, 2011, and appropriate sections in Official Methods of Analysis, 21st Edition, published in 2019, of the Association of Official Analytical Chemists (A.O.A.C.). 1. Microbiological examinations shall be conducted as follows: Appropriate dilutions shall be made with Butterfield's buffered phosphate diluent. Shake the sample and each successive dilution bottle 25 times vigorously using up and down movements of about 30 cm in seven seconds. Inoculate the water sample directly into tubes containing A-1 medium in suitable decimal dilutions using three or five tubes/dilution and a minimum of three dilutions. Place inoculated tubes into air incubator and incubate three hours plus/minus 0.5 hour at 35 degrees plus/minus 0.5 degrees Centrigade (C). Transfer tubes to water bath and incubate 21 plus/minus two hours at 44.5 degrees plus/minus 0.2 degrees C. Maintain the water level above the level of liquid in the inoculated tubes. Examine the inoculated tubes at the end of this period and record the results.