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c T E-MOE21 December 1973Vol. 182, No. 4118
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LETTERS
Deep-Sea Drilling
Deborah Shapley's report "Law ofthe sea meeting: A wet blanket forocean research" (News and Comment,14 Sept., p. 1024) was most interestingbut told only part of the story.The spokesmen for the American
scientific community have weakenedtheir prospects for a sensible regimc forocean research by their insisten:e onunlimited freedom. There is nothingsacrosanct about a research vessel. Itis just as capable of polluting the seasor creating a hazard to navigation asany ordinary vessel. Moreover, theGlonriar Chlwlcirger has demonstrated acapability to reenter the drill hole inthe ocean floor with fresh drill bits thatwouldl enable it to strike oil or eas indeep waters. At the samle time it hasno capability to prevent blowouts com-paLrable to that requirecd of conmmiiercialoperators. This m1eacIn1s that a researchvessel could possibly caLuse a blowoutof such disastroLus proportions as to palethe Santa Barbara blowout by compari-son. Yet, the spokeismen for the A-ken-tcan scientific comnilnllitV halvZe persistedin their quest for total freedoml fromcoastail nation control over scienitific re-search beyonid a narrow ter-ritorial sea.The U.S. governnment, in its initial
position in the United Nations Seabe(dCommittee, went along, with this iewNand worded its proposed draft of aninternational seabed treaty of 3 August1 970 accord inglv. Onie niced only vistu-alize the reaction of the good citizensof Salnta Barbara to word fronm Wash-ington that neither the federal -overn-ment nor their own local or state gcov-ernment had any power whatever toprevenit a foreign counlterpart of theGlo;;tar Challeigc,er from proceedingwith a deep-sea drilling experiment inthe Santa Bairbara Channel just bevondthe 12-iiile linmit to appreciate that thisposition had to he niodified as theU.S. cdelegation has now done in thelight of our own national interest andthat of other coastal natioins.The 1958 Geneva Conventioni on the
Continental Shelf, in a claause incorpo-rated into article 5 of the treaty, re-portedlvr with the active support of theUnited States, prescribes that
8 The consent of the coastal State shallbe ohtained in respect of any researchconcerning the continental shelf and tinder-takeni there. Nesertheless, the coalstal Stateshall not norrmallv xw ithhold its consent ifthe request is suhbitted by a qualified in-
stitution w ith a view to purely scientificresearch into the physical or biologicalcharacteristics of the continental shelf,subject to the prov iso that the coastalStaite shall hav e the r ight, if it so desires,to participate or to fie represented in theieseaich, arnd that in am; evexct the resultssh;all he ptirtlished
The scientific communitv has, attimies. aidmittedlx haid serious difficUltiCsobtalinina the consent recqliredL by thisclause or the comparable consent re-Cluired liy uonadhererits to the Gerievi;convention untder customary interna-tional law. These dlifficulties provide asolid basis for seekin(g iieanlillgful riiodi-fication of the quoted language. Theydo riot, however, provide a basis forits coriiplete eliniinatiori.The Ariierican Bar Associationi
(,ABA) has takeni a constructive ap-proach to this itiiportarnt problerii in theresolution on the natural resoLurces ofthe sea adopted at its last annual riieet-rig on 6 Au~uzlst 1 973. In the portinof this resolution dealing, witl sciere-tific research, the ABA
(12) SUPPORTS the gerieral principleof ft eedom of scientific rcesleath, hut recog-riizes the right of coastal States. xw ithininterri-mtionallx a-r eed -uidlelines desie>nedto pros ide the nilxiasiurll practicable ap-plication of this pririiciple, to inipose rela-son.blhe r estrictiorts on activities oti theircontinental mariiarns s hich xw ill entailthieaits to their national secrr itvol hazardsto the ensir onimierit, as hv drilling into thescabed.
The end result of the internationalnlegotiatiotls now rulldc- way is iiuLchmlore likely to be palatable to the Anier-rcari scteitific cotimiunity if its spokes-iieni xA ill stuppor-t this sensible approachto thc probleii arnd x ork xwith the U.S.delegation for its effective iriiplemerita-tion.
LUKF W. FINLAY'24 Lo(i.t 50 Street,New Yor-k 10022
Nitrites in Foods
A\. E. Wasserriian arnd I. A. Wolff,Wlio discuss the use of nitrate in theirreplx to P. H. Schuck- arid H. Well-tord (I etter-s 29 JuLe, p. 1322), doriot deal adcqUately with the ques-tioni of the use of nitrite in Cuired nieatand fish prodUcts, which Schuck andWellford suggest is an unnecessaryhazaird to health. Wasserniian and Wolffalso ignore the probleni of fortiiationof carcinogenic nitrosanilnes in vivo(I1). which SchuLck and Wellford ad-dress in their letter. It is this anmply
SCIENCE, VOL. 182
demonstrated possibility which posesthe greatest hazard to the public, andis the major reason for the proposalto eliminate nitrite from our food when-ever possible.A limit of 200 parts per million (ppm)
of r-esi(du(al nitrite in food (meat) set in1926 is arbitrary and has no scientificbasis. The preservative effect depends onthe amount of nitrite added to the foodbefore processing (a minimum, so itis said, of 150 ppm). After processing.the residual nitrite can be, and oftenis, as little as 10 ppm in, for example.ham or canned luncheon meat. It isthis residual nitrite which takes part innitrosaninle formation in vivo, and itwould seem that an ulpper limit of 200ppnm is far higher than indicated byg,ood nianufacturillg practice, and highenouLgh to be a threat to health.Wasserman and Wolff state that there
is a long history of usage of nitrate(and, by implication, of nitrite) withapparent saifety. This is an uinwarraniitedconclusion, since cancer is a widespreadand comnmon affliction. the caLuse ofwhich is uinkinowni. Evidenice is ac-cUrmulating aboLut the formation ofnitrosanminies from nitrite and secondaryor tertiary amiines (agrichemical resi-dLues, drugs, and so forth), both in foodand in vivo, which sugIgests that nitros-amines formiied in this waxl are a CaluSeof cancer (2), perhaps the major one.If, as Wasserman a.nd Wolff suggest, theavoidance of botulinus poisoning takesprecedeiice over the possible carcino-gCIliC hazard fromI nitrosanilne fornia-tioin consistency would demand thatfood Manufacturers add nitrite to allproduLcts in which a botulisnm hazardexists. One can assumie that this istheir recommendationi for vichyssoisesoup anid processed mushrooms, largebatches of which have been recalled inthe past year or so because of the find-ino, of Clostri(dlum hotilliinuni contami-nation in sonie saniples. The feedingstudy of' Van Logten et al. ( 3), citedby Wassermani andi Wolff, is irrelevant,as the usually accepted practice intoxicology was not followed, namely theadministration of greatly exaggerateddoses (often 100 times or more thehuman exposure) to compensate forthe sniall iiuniber of aninials (180) inthe experinient. The results of this 2-year feediiig test (in which niitrite wasadded to the meat), cannot possibly beextrapolated to the experionce of mil-lion.s of huianmWIs who might consunmeproportionate doses of nitrite for 50years or niore. Moreover, this experi-nient did not test the possibility of
21 DECEMBER 1973
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CYTO LOG I STS:now prepare more slidesin less time, with less fluid
who want to cut back on periodicals.After all, Garfield does say (p. 474),It is apparenit. even from the makeupof this partial listing, that a good multi-
SCIENCE. VOL. 182
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formation of nitrosamines in the stom-ach.
Wasserman and WolfT state thcat thereis no correlation of the amounts ofnitrosamines that might be ingested un-der normal conditions with develop-nment of harnmful effects, in man or ani-nmals. I draw their attention to thephilosophy behind the Delaney Amend-ment-any amount of a known carcino-gen is a hazard. To talk of the poteni-tial hazard of nitrosamines found infood is obfuscation, since these are car-cinogens several orders of magnitudemore potent than aminotriazole orcyclamates, which have been banned bythe government. The benefit of thedoubt should be givenl to the publicrather than to the food processors.SuLrely it is time that Iiitrites (and ni-trates) were removed from the GRAS(generally regarded as safe) list, aswere cyclamates, untit such time asthey are proved safe for human con-sumnption beyond a reasonable doubt.
W. LIJINSKYBiology Division,Oak Ridge National Laboraatory,Oik Ridge, Tennessee 37830
References
1. W. Lijitnsky and S. S. Epstcin, Natlure (LFrod.)225. 21 (1970)).
2. W. Lijinsky, H. W. Taylor, C. Snyder, P.Nettesheim, i1i(d. 224. 176 (1973).
3. M. J. Van Logten, E. M. den Tonkelaar, P.Ki-ocs, J. NI. Berkvens, G. J. van Esch. Food(osmet, Tovi ol. 10. 475 (1972).
Journal Evaluation
Garfield, in his empirical study "C ita-tion analysis as a tool in journal evalua-tion' (3 Nov. 1972, p. 471) comlparesSolidi State Physics, Immunology,Joit naitl of Experimlental Analysis ofBehavior, Chemical Review, and otherjoLrnals with small intersections ofcomtmton interest. This seems strange,buLt lacceptiable. as long as the dataare uised carefully. However, becauseI wondered why there were Ino gen-
cral geology journials listed in the152 most frequently cited journalsrainked by imp1act factor (figure 8. p.477), 1 talked to a science and tech-nolog,y librarian and was struck withthe potential for misuse of this article.Garfield's study can, and probably will,be misused by library administrators
---
disciplinary journal collection need con-tain no more than a few hundred titles.That is not to say that larger collec-tions cannot be justified, but it doessay something indisputable, in termsof cost and benefit, about how large ajournal collection need be (or howsmall it can be) if it is to provideeffective coverage of the literature mostused by research scientists" (italicsadded). Also (p. 477), "Another ap-plication, which harried librarians maywelcome, is the correlation of data oncitation frequency and impact withsubscription costs. Such a correlationcan provide a solid basis for cost-bene-fit analysis in the management of sub-scription budgets." One might add thatit can also provide a tenuous basis,since "harried" librarians, by definition,would be unlikely to analyze the analy-S1S.Some years ago (1) I expressed
doubts about the effectiveness of cita-tion analysis as a tool for evaluatingindividual authors, and I have some ofthese same doubts about Garfield's useof citation analysis as an evaluativetool for journals. The publication ofpapers that are original, creative, andcite few other papers would be in-hibited. Editorial preference would begiven to papers with prolific citationsof the publishing journal and of jour-nals with which they have friendlyaffiliations. In some cases, refereeswould require that references to theirown papers be included before a paperis accepted for publication. These kindsof pressures would result in the inclu-sion in papers of many unjustified cita-tions and would lead to distorted evalu-ations.
It seems, also, that answers to manyof the "Unanswered questions" in the,closing section of Garfield's articlecould have been hypothesized, and thestudy could have been based upon anexperimental design to determine theusefulness of the hypotheses. InsteadGarfield uses a purely empirical ap-proach, mixing apples, oranges, andad hoc speculations.
N. C. JANKEDepartment of Geology,California State University,Sacramento 95819
References1. N. C. Janke, Science 156, 892 (1967).
The analysis of journal citationsdescribed by Garfield provides foodfor thought, since many scientists have alargely unproductive reading list. The21 DECEMBER 1973
reason for this broad scanning of theliterature is not only the diverse natureof the interests of many active workers,but also that many are working infields that overlap disciplines. Thejournals listed by Garfield as most fre-quently cited are major field journalsdevoted to broad coverage of highlypopulated disciplines.
It is significant that no veterinary,animal science, or pathology journalsare listed. These fields are well coveredby a relatively large number of jour-nals, considering the number of peopleactively engaged in full-time research.They are also fields in which a workermust draw from many disciplines toprovide a basis for his work. Oneworker may publish regularly in basicjournals and in those devoted to hisdiscipline. These factors place the jour-nals serving the low-population, inter-disciplinary fields at a marked disad-vantage in any "numbers game" evalua-tion.
I would be loathe to see any policydecisions made from such a prelimi-nary, all-encompassing study, particu-larly by libraries assessing their journalcollections. The library is a store ofinformation to be used, not to be keptor maintained for itself. It is a serviceto the community that supports it. Inthisi regard a journal has served itspurpose if it is consulted once. Howmany consultations make a citation?Too many libraries have lost the serviceconcept without their being given a"numbers game" basis for their policies.
R. W. BIDEAnimnal Diseases Research Institute,Post Office Box 640,Lethbridge, Alberta, Canada
Several earth scientists have askedwhy geology journals were not repre-sented on the list of 152 high impactjournals. The list originally submittedcontained 565 titles. The AmericanJournal of Science ranked 182nd byimpact; the Jolurnal of Geology ranked240th.
Information on the most frequentlycited 1000 journals has now beenpublished (1) in the IS! Journal Cita-tion Reports (JCR), issued by the In-stitute for Scientific Information. TheJouirnial of Petrology ranked 50th.However, this should not obscure thefact that most geology journals do nothave a broad impact. The most im-portant general "geology" journals in-clude Science and Nature. They arecited in geology journals more often
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than most specialized geology journals.It is interesting that Janke does notmention the Journal of GeophysicalResearch, which ranked 60th; Geo-chi;nica et Cosinochimica Acta (104th);and the Jouirnal of Sedimentary Petrol-ogv (146th). Similar comments couldbe made with respect to other fields,such as veterinary science and pa-thology, which are more dependent onbasic biomedical and multidisciplinaryjournals than on those in their ownnarrow specialty.
Certainly JCR and other citationdata cani be misused. But so can othertechniques. Objective sociometric dataoiQ statistics can be manipulated forroitical or other objectives. Shouldwe abandon the census for this rea-son?A number of "harried" librarians
and departmental chairmen are usingJCR data to weed out rarely used,ournals but also to add journalspreviously excluded. Most scientistsare aware that society is demandingmore efficiency in the operation ofresearch estabiishments, but Janke andBid2 do not discuss cost-effectivenessfor libraries with finite budgets. Bidewculd ,ustify the purchase of expen-sive journals even if they are usedonly once. Weinstock (2) demolishedan earlier assertion that a library canaspire to order anythinig and every-thing. The ultimate extension of suchan assertion. is that each specializedlibrary should become a Library ofongress.Janke refers to his previously ex-
pressed doubts aboLut citation analysisbut doesn't cite any evidence to sup-port his earlier contentions. Can hennr'vide any examples of "papers, how-cver bad, being heavily cited, whileothers remain uncited because theyare too far ahead of their time" (3)?The assumption that original and
creative papers cite few other papersis conmpletely contrary to fact. In the10 years that the Science Citation In-de.v h(as been published, there has notbeen any perceptible change in therate of citation by or to the averagepaper.The factual answers to many of
the speculative questions I posed inmiiy article are available in my weeklyarticles in Clurrlent Conltenits (4). IgJadiy confess that I am an empiricist.
CouLntless examples could be citedto prove that the impact numbersgame can work to the advantage ofsmall journals that would otherwise beneglected in favor of larger or more
familiar and prestigious journals. Fur-thermore, before the existence of JCR,would it have been obvious that thevirology journals had become basicto plant pathology collections, or thatthe Jour-nal of Experimental Medicinecovers mainly immunology, or thatthe Journzal of Petrology, although636th in citations, ranked 50th byimpact? (The last observation is baseden data compiled after my article waspublished.)
Bide and Janke seem to give mycolleagues in the library and informa-tion sciences little credit for theirability to analyze data.
EUGENE GARFIELDIn.stii ate for Scientific Information,.3295 Chestnut Street,Phi!adelphia, Pennsylvania 19106
References
t. ISI Jouirnal Citation Reports (JCR): part 1,Joiurnial Ranking Pa kage; part 2, ReferetnceData; rait 3, Sourr e Data P/a kage (institutefor S ientific Information, Philadetphia, 1973).
2. M. Wienstock, Nature (Lond.) 233, 434 (1971).3. N. C. Janke. Scietnce 156, 892 (1967).4. E. Garfield, Cuir. Conitenits, No. 31, p. 5 (4
AtuguIst 1971); No. 45, p. 5 (10 November1971); No. 2, p. 3 (12 January 1972); No. 5,p. 6 (2 Februiary 1972); No. 7, p. 5 (16FebruLary 1972); No. 8, p. 6 (23 February1972); No. 9, P. 5 (I March 1972); No. 14.p. 5 (5 April 1972); No. 16, p. 5 (19 April1972); No. 23, p. Ml (7 June 1972); No. 31,p. 5 (2 ALIgUSt 1972); No. 3, p. 5 (17 January1973); No. 6, p. 5 (7 February 1973); No. 10,p. 5 (7 March 1973); No. 12, p. 5 (21 March1973); No. 13, p. 5 (28 March 1973); No. 22,p. 5 (30 May 1973); No. 33, p. 7 (15 August1973); No. 34, p. 5 (22 August 1973): No. 39,p. 5 (26 September 1973).
Mesoamerican Calendar
My attention has been called to anerror in my report (7 Sept., p. 939) onthe Mesoamerican calendar. Charles H.Sniiley of Brown University has kindlypointed out that it is only the Good-man-Martinez-Thompson correlationwhose zero starting point correspondsto the zenithal sun position I havepostulated as the origin of the Meso-american calendar, and not the Spindencorrelation, which is some 52 days outof phase with it. Thus, inadvertently,my findings have provided furtherreason to accept the validity of theformer system and to finally reject thelau,Ier. Tais conclusion is also war-
ranted by ladiocarbon dating done atthe University of Pennsylvania andcalled to my attention by Henry N.Michael of Temple University.
VINCENT H. MALMSTROMDepartment of Geography and Geology,fiddlehury College,
.Aiddicclehurv, Verm-lcont 05753
SCIENCE, VOL. 182
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New automatic CO2 incubator.From Forma. Automatic.Just set the desired C02 level and the incubatormaintains itself within + 0.20 C, reducing C02 con-sumption by as much as 95%. Readout is continuouson a large 4" scale meter; there's a panel-mounted CO2flow indicator. An even distribution of internal C02environment eliminates CO2 stratification. Temperatureand humidity are uniform throughout the chamber withno air supply required. The chamber is automaticallyand quickly replenished after door openings, eliminatingthe need for manually activated recovery systems.Reliability is built in, with solid state electronics andstainless steel construction.Write or call Forma for further details.
Forma Scientific®BOX 649- MARIETTA, OHIO 45750 614/373-4763 TELEX 24-5394
Circle No. 90 on Readers' Service Card
HUMAN EVOLUTIONNew teaching and study aids:
. Catalogue/Workbookof high gradeprimate casts FROM THE WENNER-GREN FOUNDATIONFOR ANTHROPOLOGICAL RESEARCHStudents, teachers and researchers interested in human evolution cannow acquire epoxy casts of contemporary primates and fossil remainsmolded with exceptionally high reliability to detail from originalspecimens. The specimens cast were selected by the Wenner-Gren Foundation in collaboration with internationally recog-nized leaders in the fields of primatology, anatomy and paleoan-thropology. The selection allows use of the casts individually orin integrated programs of teaching and study.An illustrated catalogue of casts has been designed with the :
dual purpose of facilitating acquisition of the casts and as aworkbook-teaching aid for instructors and students. The priceof the catalogue-workbook is $3.85 for a single copy, or $3.50, 4each, for orders of 12 or more. Shipping and handling chargesare additional.
Address all inquiries to:The Wenner-Gren Foundation for Anthropological ResearchCasting Program, P.O. Box 618, Lenox Hill Station, NewYork, N.Y
Circle No. 61 on Readers' Service Card21 DECEMBER 1973
You oet a lot more than a pH
You get Dick Keatingand colleagues.
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meter when ylou bUY Beckman.Good pH meters like ours last a long time. Mostof our first ones, nearly 40 years old, still per-form accurately today.And when all's well, you couldn't care less abouta Dick Keating.But when a problem pops up, or a tough applica-tion needs untangling, you'll know why Beckmanhas Dick Keating in New York, Jim Bahre inWashington, Joe Velisek in Chicago, Mike Beattyin San Francisco, Fred Eden in Houston and 425other sales and service representatives on callall over the country.
We're the only pH manufacturer that offerssuch extensive direct contact. Factory/field-trained representation everywhere. Availableto you personally for assistance, advice and solu-tions. And on really sticky problems, you'll getadded expert help from our Applications Lab-oratories in Los Angeles, Chicago, or Mountain-side, N.J.
We don't have to do much equipment trouble-shooting. The extensive Beckman line of modernpH instrumentation assures you the exact com-bination of equipment to do your job right...and trouble-free. Meters for every purpose,
TN0- simple to sophisticated; electrodes for everyapplication, including the difficult tris buffers.
But though the instrumentation is relativelysimple, pH techniques and interpretations canbecome complex. About 80% of the calls we getare asking for technical help on pH. And wehave the instant answers - on file - becausewe've handled and solved nearly every pHproblem that's come up since we produced theworld's first commercially available pH meter.
INSTRUMENTS, INC.
That's why you should think about Dick Keatingand his colleagues. Before you need them.Theyoffer you the finest pH product line going, andthey can prove it. But they also offer you anexclusive reservoir of personal help. And there'sno substitute for that.
Circle No. 5 on Readers' Service Card
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Most ofyour Blo Med problemscan be solved by an unknown.
-Say goodbye to tme sharing. Give the pocketcalculator to your kids. Stop wasting your timedoing math with a pencil.aIf you've got statistical problems, we've got
asolution. The Compucorp Micro Statistician.The professional's machine.
The Statistician is a hand-held, batteryoperable Micro Computer that thinks the wayyou think.
It does blood gas analyses. Works chemistryproblems. Breezes through medical calculations.Cures pathological headaches. Separatesmedical facts from fiction.
The Micro Statistician is the first and onlyhand-held Micro Computer with built-in standarddeviation (grouped or ungrouped), linearregression, ze-score, -dependent and independent,logs and anti-logs, coefficient or correlation,expected y from regression coefficients, slopeand intercept.
The Micro Statistician is also the first hand-held statistical machine that's programmable.
\;It allows you to have two 80-step programs inmemory at the same time. Which means
repetitive calculations are a snap. You can do register arithmetic in and out of all ten storage regis-ters. And you can set the decimal point anywhere you want it. And change it whenever you want to.
The Compucorp Statistician is the first hand-held machine with 13-digit accuracy and a big,bright 10-digit display. It's also the first one with an algebraic keyboard and nested parentheses.
Get all the facts on Compucorp Micro Computers. We may be an unknownto you,but we're already solving tough Bio Med problems around the world.
See your local Compucorp dealer. Or write Computer Design Corporation,12401 Olympic Boulevard, Los Angeles, California 90064.
CompucorptThe Unknown Factor in 63 countries.
Circle No. 7 on Readers' Service Card
