Commerical testing laboratories

We have also been concerned about the problems in the practical application of various short-term tests in commerical testing laboratories. The problems emerging in the evaluation of potentially important new chemicals have been discussed in a chapter by Brusick et ai... 

Valves. Limited laboratory testing shows that emulsions can be let down across a pressure differential of 1000 ij/ (6895 kPa), typical of commer-... 

A useful qualitative screening test for salicylic acid is performed by adding a few drops of glacial acetic acid or 0.1N hydrochloric acid to 1 ml of urine, followed by 3 drops of 10% ferric chloride solution. A burgundy red color appears and persists if salicylic acid is present (color may turn reddish brown in the presence of phenothiazines). A serum salicylate level can be obtained in most laboratories. Commerically available test strips may be used with urine as well as serum or plasma to determine the presence of salicylic acid. These tests react only with salicylic acid and therefore do not work on stomach contents or pills, but any salicylate is hydrolyzed in the body to salicylic acid and would be present as such in blood or urine (15). 

Table 1 shows what cun be measured in a blood sample outw ith the noniial laboratory setting. The most common blood test outside the laboratory is the determination of glucose concentration, in a finger stab sample, at home or in the clinic. Diabetic patients who need to monitor their blood glucose on a regular basis can do so at home or at w ork ii s i ng one of many commer-ciiilly available pocket-sized in.struments. 

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