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nce in awhile (daily?), we analytical chemists who read the news should note instances in which our subdiscipline has made a positive contribution to society. I do this myself regularly, with pride in both the applied and fundamental aspects of such contributions. This Editorial is to share some observations of this sort with you. I must also remind you that we analytical chemists can do our thing well only because other chemistry subdisciplines do theirs well and that the advancement of science is a creature of symbiotic creativity. There are plenty of examples in the recent (U.S.) print news in which analytical chemistry is an underlying theme, including detecting residues of unapproved aquaculture antibiotics in imported seafood, lead-containing paint on fashionable imported toys, deadly adulterants in imported toothpastes, and the sad examples of cheating with body-enhancing drugs in sports competitions. Reading these news reports, I am chagrined that the public is usually given a very shallow picture of the underlying science, including the analytical input. (For a more thorough exploration of analytical chemistry and sports doping, see pp 5522–5528.) There is also a recent item of historical interest—a report that domestication of crops (squash, peanuts, corn) in the New World may have occurred much earlier than previously thought (Science 2007, 316, 1830–1835). Let me elaborate on the news about imported seafood: on June 29, the New York Times reported that the U.S. Food and Drug Administration (FDA) had blocked imports of several kinds of seafood after finding in them—not for the first time—unapproved and potentially carcinogenic residues of antifungals and antibiotics. One of the residues, malachite green (MG; 4-[(4-dimethylaminophenyl)-phenyl-methyl]N,N-dimethyl-aniline), is a topical aquaculture fungicide that, upon metabolic reduction to the lipophile leuco-MG, is retained in the fatty tissues of fish, eels, and shrimp. The Times article did not mention these details, nor that the presence of MG was determined by ion trap LC/MS and quantitated by a series of solvent and solid-phase extraction procedures followed by HPLC at an LOD of 1 ppb. I found a standard procedure on the FDA website giving the details without which the innocent lay reader might wonder how a substance with a dyestuff name gets involved with fish! © 2007 AMERICAN CHEMICAL SOCIETY
FDA is now requiring importers of the aforementioned seafoods to provide a third-party, independent analysis—using any method acceptable to FDA—of each import lot. This prompted me to spend some time looking at analytical testing laboratories, and I came away convinced that they are probably good investments. Seafood contamination is not a small matter, because the U.S. imports >5 billion lb of seafood annually, 22% of which comes from the offending exporter country. The news report mentioned criticism of FDA for not blocking the imports at an earlier date. I took a tour of the relevant FDA website (www.fda.gov/ora/science_ref/default.htm) and was rather amazed at the magnitude of the contaminant import problem—across many kinds of goods—and at the huge number of import shipments that were refused in just one month (May 2007). The refused shipments are listed by reason, country, and date (www.fda.gov/ora/oasis/ora_oasis_ref.html). One cannot help but gather a renewed respect for the FDA analytical chemistry community’s expertise and watchfulness and wish that federal regulations would require listing the country of origin of accepted imports to inform the consumer. Let me, lastly, mention the story about early crop cultivation in the New World (specifically in Central and South America). The Science article cited earlier tells how squash seeds discovered in an ancient dwelling place in the Peruvian Andes have been dated to ~10,000 years ago. The authors surmise this to be evidence of primitive domestication of that plant, which might be a stretch but certainly opens new windows on the lives of the earliest Immigrants. The point I wish to make is the crucial measurement of the age of the seeds, which was—you guessed it—by carbon dating with mass spectrometric isotope ratios. This sophisticated measurement technique is so mature that the authors barely mention it. I leave you here, admonishing you to read the news and look for continued triumphs of analytical chemistry.
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