Sewage Discharge and the Mersey Estuary* Co-operation in Technical Research

Off-flavours in fish were studied from 1969 to 1981 at the Food Research Laboratory of the Technical Research Centre of Finland using sensory methods. In all, 1982 samples of 18 species of Finnish fish, most of them suspected of being tainted, were studied. A trained taste panel scoring on a numerical scale of 0-10, where a score of 5 or less was unacceptable, was used. The off-flavours described were oil, kraft pulp mill effluent, sewage (musty), muddy, rancid, and others. Of all these samples, 34.9% were unacceptable. The most common off-flavour was kraft pulp mill effluent, present in 41.2 % of the unacceptable samples. In acceptable fish slight off-flavours were somet imes found. Of the muddy fish, only 35.2 % of the bream and 28.8 % of the northern pike were unacceptable. The panel was able to discriminate between the different off-flavours, but, in some cases, the boundaries were vague.

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Detection of giardia and cryptosporidium in marine waters

Water Science & Technology ◽

10.2166/wst.1995.0655 ◽

1995 ◽

Vol 31 (5-6) ◽

pp. 439-442 ◽

Cited By ~ 12

Author(s):

D. C. Johnson ◽

K. A. Reynolds ◽

C. P. Gerba ◽

I. L. Pepper ◽

J. B. Rose

Keyword(s):

Health Risk ◽

Tap Water ◽

Polypropylene Fiber ◽

Marine Waters ◽

Sewage Discharge ◽

Antibody Staining ◽

Parasite Detection ◽

Cartridge Filter ◽

Overall Efficiency ◽

Immunofluorescence Antibody

Raw sewage disposal in marine waters is a common practice in many countries. This practice raises health risk concerns of possible transmission of Giardia and Cryptosporidium. Both of these protozoa have been shown to be transmitted by recreational swimming. To date no studies have determined the efficiency of their detection and concentration in marine waters. This study evaluated the efficiency of their detection in tap water and from marine waters in Hawaii with two different filter types. This study compared a polypropylene fiber cartridge filter, DPPPY (1.0 μm nominal porosity) (Cuno, Meriden, CT) which is typically used for parasite detection and the Filterite negatively charged filter (0.45μm) (Filtemp Sales, Inc., Phoenix, AZ). The latter would allow for both viruses and parasites to be concentrated simultaneously. The organisms were removed from the filter by passing the eluent through the filters in the opposite direction of collection and detected by indirect immunofluorescence antibody staining specific for Giardia and Cryptosporidium. Processing was simpler and faster with the Filterite filter and the overall efficiency for both Giardia and Cryptosporidium detection was greater. These methods are currently being used for the detection of the oocysts and cysts at bathing beaches in Hawaii impacted by marine sewage discharge.

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