appendix E10

Notes:

1 ISO 9308-1 permits all three methods to be used. UK now uses membrane filtration with 0.1% sodium lauryl sulphate broth; incubation at 30°C for 14 hours for faecal coliforms. Faecal coliform isolates are confirmed, giving a count of Escherichia coli. This procedure gives the best recovery (highest counts) of various media tested and is standardised in NRA microbiological methods manual (National Rivers Authority (1992)).

2 Methods are given in ISO 9308-2, which is being revised. Teepol broth is obsolete, Endo agar inhibitory to damaged coliforms. UK uses long-established procedures in The Microbiology of Water 1994 - Part 1 - Drinking Water, HMSO, London. UK always confirms for presence of Escherichia coli.

3 Examination of the Shellfish flesh and intervalvular liquid. Guideline value of 300 per 10 ome must be observed in shellfish harvested for direct human consumption in the waters in which they are reared. This requirement is now superseded by the microbiological requirements of the Shellfish Hygiene Directive (91/492/EEC)

4 Examples of analytical methods unchanged; the same comments apply.

5 Standard methods of ISO 7899/1 and /2, now under revision. Favoured medium is Slanetz and Bartley's (1957) m-Enterococcus agar with membrane filtration. UK procedure given in The Microbiology of Water 1994 - Part 1 - Drinking Water. HMSO, London.

6 The most used medium is Slanetz and Bartley's (1957) m-Enterococcus agar with membrane filtration. Incubation either at 37°C for 48 hours or at 37°C for 48 hours or at 37°C for 4 hours and 44°C for 44 hours. Latter procedure is very specific for enterococci and is used by UK. Former procedure is less specific for faecal streptococci and gives higher counts. Neither method, nor Litsky method is given in ISO 7899/2, which is being revised.

7 Litsky, Mallman and Fifield (1953) method is of low efficiency and obsolete. Generally replaced by membrane filtration, using Slanetz and Bartley's (1957) m-Enterococcus agar. See Note 2 for Bathing Water Directive.

8 A difficult test. UK guideline document. (Note 2) gives procedures. Draft International Standard, ISO/DIS 6340

9 Salmonella method used in UK is specified in NRA's manual. A difficult test. Salmonellae are ubiquitous in surface water and can originate from birds, waterfowl and animals, hence not specific indicator of faecal pollution. To be examined if bathing water has deteriorated or if it is suspected that they may be present

10 Not an analysis for routine use, but when waterborne Salmonellosis is suspected. UK guideline (see note 1) has procedures. Draft International Standard ISO/DIS 6340.

11 Enteroviruses are detected with difficulty, using an expensive and poorly efficient method. They are not the viruses thought to be responsible for gastro-enteritis in bathers, hence are yet another indicator of faecal contamination. To be examined if bathing water has deteriorated or if it is suspected that they may be present

12 Not a routine test.

13 The UK shellfish industry has long used a draft standard procedure (West and Coleman 1986); a multiple tube method with minerals modified glutamate medium, with confirmation of E.col}. Impedimetric methods are under development as a possible European alternative.

14 Awaits a decision on parameter level, to be inserted at a later date when information is available. Parameter could be either somatic coliphages or more likely 'male-specific' coliphages (F+ RNA coliphages), for which a draft international standard now exists ISO/DIS 10705-1. It is intended to replace the Enterovirus parameter.

15 Guélin's method obsolete. Not a routine test. Standard for F+ RNA coliphages in water now being developed as ISO/DIS 10705-1; methods for somatic coliphages in draft stages ISO/CD 10705-2 and 3. A faecal indicator parameter, not a pathogen.

16 ISO 6461-1 and 6461-2 give standard methods for multiple tube and membrane filtration methods. Suggested by WHO as a test for water treatment efficiency, since chlorine resistant (Guidelines for Drinking-Water Quality - Vol. 1 Recommendations, WHO, Geneva).

17 ISO 6222 gives procedures, but is being revised within CEN/TC230 and ISO/TC 147. UK uses incubation at 37° for 24 hours.

18 Not a routine test. Staphylococcal infections are not waterborne. Not an appropriate parameter.