REPORT FOR ANALYTICAL
CHEMISTS
Recent Laws Demand Improved Food and Pesticide Analyses W i t h a background of 75 years in developing analytical methods for use in foods, feeds, fertilizers, a n d pesticides, the Association of Official Agricultural Chemists is w e l l o r g a n i z e d to meet newer and greater challenges. Recently enacted laws relating to pesticide residues and f o o d additives w i l l require new methods, new techniques, a n d new instrumentation to attain required accuracy. "γχΐΗΈΝ is a rotten egg not a rotten V V e gg? x h e housewife with no scientific tools a t her c o m m a n d ex cept her nose can easily determine whether an egg is decomposed. W h e n t h e G o v e r n m e n t charges a food processor with distributing de composed dried eggs, however, and t h e m a t t e r ends u p in t h e courts, evidence based on odor m a y not be sufficient t o support a finding of guilty. W h a t is needed is more q u a n t i t a t i v e , reproducible evidence. W h e t h e r the item involved is eggs or any other food, feed, drug, cosmetic, caustic poison, or pesti cide, there are methods available for their analysis. These have been developed over the past 75 years by collaborative studies b y the As sociation of Official Agricultural Chemists. T h e i r "Bible," which is recognized as authoritative by regu latory and judicial authorities, is a 1000-page laboratory m a n u a l , now in its eighth edition (1955). T h a t AOAC methods are both scientific a n d objective is evidenced b y the fact t h a t some s t a t e laws specify AOAC methods and federal definitions a n d s t a n d a r d s of iden t i t y for m a n y foods incorporate AOAC methods into their require ments. M a n y federal specifications a n d p r i v a t e contracts also utilize AOAC methods. I n court testi mony, AOAC methods are accorded a preferred status. AOAC membership consists of state and federal chemists devoted to developing, testing, and spon soring improved methods for the analysis of fertilizers, soils, foods, feeds, pesticides, drugs, cosmetics, caustic poisons, and other m a t e rials related t o agricultural p u r suits. All state chemists, including those in universities a n d experimental
stations, are AOAC members. F e d eral organizations represented a r e : Food and D r u g Administration, Public H e a l t h Service, D e p a r t m e n t of Agriculture, D e p a r t m e n t of I n terior, D e p a r t m e n t of Defense, I n ternal Revenue Service, and N a tional B u r e a u of Standards. I n spite of all the work AOAC has done, unsolved problems t o d a y are probably greater t h a n ever before. T h e Miller Amendment to the Federal Food, D r u g , and Cosmetic Act has opened a whole new area of regulation with regard to pesti cide residues on crops. T h e last Congress passed a law relating to the regulation of food additives. The new methods involved in these two areas will be great and will require years of method develop ment.
Background of AOAC
T h e public t o d a y assumes, and generally correctly so, t h a t foods, drugs, and cosmetics are as de scribed on t h e label and not a d u l terated. I t was not too long ago, however, t h a t the consumer had no such assurances. I n these early days there w a s more concern with fertilizers and animal feeds t h a n with food a n d drugs for h u m a n s . Conditions prevailing in t h e late 1800's, just prior t o t h e establish ment of t h e AOAC, are well d e scribed by the late H a r v e y W . Wiley, often called the F a t h e r of t h e P u r e Food Laws, a n d founder of AOAC. The condition of agricultural chemi cal work in the United States in 1880 was a ipeculiar one. The few chemists who were engaged in agricultural re-
Specially equipped planes are used t o spray areas with high population of grasshoppers. The plane shown is used t o spray range land VOL. 3 1 , NO. 1, JANUARY 1959
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REPORT FOR ANALYTICAL CHEMISTS
The late Harvey W . W i l e y shown at his laboratory in the U. S. Depart ment of Agriculture at the turn of the century
search were acting in complete inde pendence of each other in regard t o methods of investigation a n d of re search. Some of t h e m were using the methods employed b y German chem ists, while others followed the instruc tion given b y the F r e n c h or English agricultural chemists. There was no u n i t y of interest in the profession n o r any common system of work: The condition of analytical work m a y be t r u l y described as chaotic. T h e result of such condition is easily imagined. There was no s t a n d a r d of comparison or reference. Buyers a n d sellers were continually wrangling over analysis, which, m a d e b y different m e n follow ing different methods, did not agree. T h e sellers' chemists uniformly o b tained higher results t h a n t h e buyers', a n d thus the door to litigation was constantly open. Strange as it m a y seem, the first steps t o w a r d correcting this pitiable condition did n o t come from t h e D e p a r t m e n t of Agriculture a t Washington, b u t from the d e p a r t m e n t of agriculture of one of the states. I t was t h r o u g h J. T. Henderson, Commissioner of Agri culture of Georgia, a n d a t the instiga tion of H . J. Redding, now director of the Georgia station, t h a t the first step toward uniformity of action among agricultural chemists of the United States was taken. Initial Organization. In M a y 1880, t h e p r e c u r s o r of A O A C m e t . T h e i r concern w a s solely w i t h a n a l y t i c a l m e t h o d s for d e t e r m i n i n g phosphoric acid, nitrogen, a n d p o t ash in fertilizer a n d especially t h e phosphoric acid. I n A p r i l 1880, t h e r e w a s a m e e t i n g in B o s t o n as
a s e c t i o n of t h e A m e r i c a n A s s o c i a t i o n for t h e A d v a n c e m e n t of S c i ence. T h e third and last meeting w a s h e l d in C i n c i n n a t i i n 1 8 8 1 . These early meetings, which were k n o w n as c o n v e n t i o n s of a g r i c u l tural commissioners and chemists, were attended by commercial and government chemists and both g r o u p s w e r e r e p r e s e n t e d on c o m mittees. A t t h e l a s t m e e t i n g in 1881, commercial interests collided w i t h " t h e s e a r c h for t r u t h , " D r . Wiley notes. The Chemical and Fertilizer Exchange claimed t h a t t h e m e t h o d for c i t r a t e - s o l u b l e p h o s phoric acid did " c r y i n g injustice t o the guano trade and to the farmer b y giving lower results t h a n would a modified p r o c e d u r e . " I n M a y 1884, H e n d e r s o n c a l l e d a c o n f e r e n c e in A t l a n t a t o a d o p t a " u n i f o r m a n d , if p o s s i b l e , a m o r e g e n e r a l l y s a t i s f a c t o r y m e t h o d of a n a l y s i s in t i m e t o e n a b l e m a n u f a c t u r e r s , if n e c e s s a r y , t o c o n f o r m t o t h e s a m e in p r o m u l g a t i n g t h e i r w o r k of a n d for t h e n e x t s e a s o n . " Later that year AOAC was be gun in P h i l a d e l p h i a . In Septem ber 1885, t h e association held its second meeting, at which t i m e t h e C o m m i s s i o n e r of A g r i c u l t u r e s u g gested t h a t the A O A C n o t limit itself t o f e r t i l i z e r a n a l y s e s b u t e x t e n d i t s efforts in g e n e r a l c h e m i c a l a n a l y s e s a n d i n t h e a r e a of p u r i t y s t a n d a r d s for f o o d s a n d m e t h o d s of d e t e c t i n g a d u l t e r a t i o n . T h e first p u b l i c a t i o n of A O A C m e t h o d s ( 4 9 p a g e s ) a p p e a r e d in 1885. T h i s historic publication a l s o i n c l u d e d t h e t e x t of t h e first constitution. A O A C Objectives. In p a r t , t h e constitution reads: I . This Association shall be known as the Association of Official Agricul t u r a l Chemists in t h e United States. I t s object shall be to secure, as far as possible, uniformity in legislation with regard t o the regulation of t h e sale of commercial fertilizers in t h e different states, and uniformity and accuracy in the methods and results of fertilizer analysis. I I . Analytical chemists, connected with d e p a r t m e n t s of agriculture, state agricultural experiment stations and state boards, exercising an official fer tilizer control, shall alone be eligible to m e m b e r s h i p ; and one such representa tive from each of these institutions, when properly accredited, shall be en titled to a vote in the Association. All
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REPORT FOR ANALYTICAL CHEMISTS
analytical chemists and others interested in the objects of the Association may attend its meetings and take part in its discussions, but shall have no vote in the Association. B y 1899, AOAC had become a healthy, growing organization. I t was interested in food standards and h a d method studies under w a y for spices, dairy products, table salts, grain standards and cattle feeds, sugars, vinegars, and adult e r a n t s . AOAC gave up its food s t a n d a r d s work, since proposed federal legislation was not enacted. I t was not until t h e Food, D r u g and Cosmetic A c t of 1938 was passed, t h a t the Food and D r u g Administration obtained authority to promulgate a n d enforce such standards. Basic Policy. A basic policy of AOAC is t o improve and expand the scope of its methods continually. Methods are based on collaborative efforts of a large number of workers. Phraseology is scrutinized most carefully to ensure clarity. Methods t h a t prove acceptable to both regulatory chemists and those in commercial activities, generally prove to be as good as can be devised. However, if an improvement is possible, it is adopted. This policy h a s led to the acceptance of AOAC methods as authorit a t i v e , both by scientists and the courts. AOAC meetings now draw almost 1000 chemists. About one third are from industry, one third from nonregulatory federal agencies, and the balance divided between federal and state regulatory agencies, state agricultural colleges, state experiment stations, and C a n a d i a n representatives. While AOAC's functions include both research and regulatory a c tivities, emphasis in recent years has been placed on analytical methods which constitute good regulatory tools. Newer analytical tools such as chromatography and spectrophotometry are very useful in these studies. AOAC Organization and Method Development
Over the years, the concept developed t h a t it was a governmental
function to control and regulate such commodities as foods, feeds, drugs, cosmetics, caustic poisons, and pesticides. Paralleling this development was the increased r e sponsibility placed on the regulatory scientist. I t became his r e sponsibility to develop accurate and reproducible methods of analysis required for the improvement of laws and regulations. Such m e t h ods were and are being developed by AOAC scientists. AOAC, whose official name is the Association of Official Agricultural Chemists of North America, establishes its methods through a referee system. T h e organization has a president, vice president, and secretarytreasurer elected annually. These officers plus the immediate past president and three other active members elected by the association constitute the Executive Committee. T h e president, with concurrence of the Executive Committee, a p points the chairman and 12 members of a committee called the Committee on Recommendations of Referees. One third of t h e m e m bers are appointed each 2 years and serve for 6 years. T h e chairman is appointed annually. T h e committee chairman assigns subjects to four subcommittees. H e also a p points three committee members to each of these subcommittees. The president and secretary a p point referees from among the active members on general subjects designated by the Referee's Committee. Associate referees are selected from available chemists, members or nonmembers. T h e referees and associate referees direct and conduct research on methods and subjects assigned, prepare and distribute samples, direct and conduct collaborative studies of methods, and present results and recommendations for methods a t each annual meeting. Methods which have received collaborative studies and have been recommended by t h e referee are designated "first action." After a t least one year, and upon recommendation of t h e appropriate referee, a method becomes "official." Official methods m a y be changed or repealed only after collaborative
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REPORT FOR ANALYTICAL CHEMISTS
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ANALYTICAL CHEMISTRY
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study and recommendation by the referee a t two a n n u a l meetings. U p o n r e c o m m e n d a t i o n of a r e f e r e e , AOAC m a y adopt well-established p r o c e d u r e s for e x a m i n a t i o n or t r e a t m e n t of a m e c h a n i c a l , m i c r o s c o p i c , p h y s i c a l , c h e m i c a l , or o t h e r n a t u r e . T h e r e a r e n o w a p p r o x i m a t e l y 45 r e f e r e e s e a c h of w h o m is s e r v e d b y f r o m one t o 3 3 a s s o c i a t e s . The t o t a l n u m b e r of r e f e r e e s a n d a s s o ciates exceeds 300. These men serve w i t h o u t remuneration. This g r o u p s t u d i e s m e t h o d s of a n a l y s i s g r o u p e d in 50 g e n e r a l c a t e g o r i e s ranging from " a g r i c u l t u r a l liming materials" to "waters." Consider a b l e e m p h a s i s is p l a c e d o n p e s t i c i d e r e s i d u e s a n d food a d d i t i v e s . A c c o r d i n g t o A O A C officiais, t h i s o r g a n i z a t i o n a l s e t u p f u n c t i o n s ef fectively. Its methods meet with general acceptance b y most chem ists.
A h y p o t h e t i c a l c a s e s h o w s how an A O A C m e t h o d comes into being. This illustrative example, written b y W . B . W h i t e (1), a p p e a r e d in t h e Food Drug Cosmetic Law Journal ( J u n e 1597, p a g e 3 3 8 ) . Suppose t h a t the scientific or t r a d e literature comes out with the proposal to p u t some chemical into food for some purpose or other which—to the pro poser, at least—is a most laudable one. Suppose, further, t h a t Food and D r u g Administration inspectors actually en counter this use in one or more food manufacturing plants or perhaps state men make t h e discovery and communi cate it to AOAC officials or to the Food and D r u g Administration. Such a situ ation, of course, a t once poses a prob lem in methods, sharpened perhaps by the fact t h a t the exploiter of the chemi cal has no knowledge of its possible harmful effects on the consumer, being activated only by an all-too-common bland optimism on this vital issue. T h e problem t h u s is how accurately t o de termine the chemical (1) in the pres ence of all the ingredients which might be normal to the particular food and (2) in such body fluids as blood and urine, and p e r h a p s in body tissues or organs as well (in case regulatory phar macologists foresee the need of studies on the potential threat to consumer h e a l t h ) . Here we are dealing with t h e need of a wholly new method rather than with the other situation of a need for a better, quicker, or more specific method to supplant or supplement an existing one; the AOAC machinery
swings into action in much the same way in either case. T h e need is com municated a t once to the general referee, together with all available in formation as to collateral methods or studies, if any, in the literature which promise to throw light on the problem. Perhaps the referee already has an associate referee who has been assigned the particular subject m a t t e r by his own agency because of his knowledge, interest, and experience ; if not, steps are taken b y the AOAC to appoint such a m a n . I n any case this m a n proceeds to devote as m a n y of his wak ing hours to the problem as his job will permit—perhaps this is an i m p o r t a n t p a r t of his job anyhow. H e stays with it, using what assistance he can muster among his colleagues and friends, until he has a method t h a t gives good re sults in his hands. T h e method is now ready for collaborative study. The associate referee plans the study very carefully, probably discussing his plan with the general referee, testing the wording of the method on his assistants and perhaps doing a little intensive small-scale collaboration with them as experimental animals. Out of all this comes a set of cookedu p samples to go out to the volunteer collaborators along with the method. If the associate referee is wise, he will advise them to do a little rehearsing on their own material so t h a t they do not "come to the method cold," as chemists say. In t h e preparation of his samples he has made every effort (1) to get an absolutely uniform mixture of chemi cal and food, so t h a t all portions sent out will be alike, (2) to ensure safe arrival in a sound condition, (3) to in clude controls or "blanks" alike in all respects to the "doped" sample except for the presence of the chemical, (4) to keep the collaborator absolutely in the dark as to which sample is which, (5) to load the food up with all the normal ingredients (such as seasonings, color ings, sweetenings, etc.) t h a t it could ever be reasonably expected to contain, and (6) to ensure in every other way possible t h a t the trial eliminates all variables except t h e well-known but little-understood "personal equation." As a rule, the collaborators are skilled along similar lines, and frequently in terested " b y first intention" with the particular problem in hand. Their re ports and comments go back to the associate referee and his, in turn, to the general referee, together with whatever recommendations as to further study, modification, adoption, or other action by the association the findings seem to warrant. T h e general referee passes these on, with his own recommenda tion, t o t h e a p p r o p r i a t e one of t h e four great subject-matter subcommittees, which then considers all the data and makes its recommendation at the next annual AOAC meeting, to be accepted or rejected at the business session on the last of the three days of t h e meet ing. During the first two days, the
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members of the appropriate subject matter section of the open meeting have listened to all of these reports and recommendations, and have had access to them if they wished, so that the whole proceeding represents democracy in its purest form. The point needs no laboring that any method which can pass through such an ordeal, and receive the accolade of "official final action," has well-demonstrated utility and reliability. "Official Method· of Analysis of the AOAC"
More than 15,000 Coleman diffraction Grating Spectrophotometers are used in laboratories throughout the world. They have gained this wide acceptance because they deliver precise data more quickly and easily than any other spectrophotometer. They have proved themselves to be rugged and reliable in laboratory service. The Coleman Universal Spectrophotometer is ideal for the laboratory with a variety of analytical problems and a heavy work-load. Fast, precise, versatile in spectrophotometry—fluorimetry—nephelometry. The Coleman Junior Spectrophotometer —the most practical and effective of all analytical tools for routine spectrophotometric analysis. 15 years of service and thousands of published procedures illustrate its reliability and recognition by the highest authorities in analytical chemistry. New literature available. Junior Spectrophotometer Bulletin B-240A Universal Spectrophotometer Bulletin B-241
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24 A
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ANALYTICAL CHEMISTRY
The "Official Methods of Analysis of the AOAC" is a laboratorymanual totaling 1000 pages. It includes 41 chapters, 90 pages of tables, and 45 pages of index. This present manual is used as an authoritative source of methods of analysis by the regulatory chemists and agricultural scientists throughout the world. The manual is in a constant state of revision and expansion. Between revisions of the manual, annual changes in methods, reports of referees, and new methods, applications, and interpretive data appear in AOAC's quarterly journal. The 8th edition is a far cry from the let edition of 49 pages, issued in 1885. This appeared as Bulletin No. 7 of the Division of Chemistry, U. S. Department of Agriculture, and was entitled "AOAC Methods of Analysis." The second methods publication appeared in 1886 and was limited to fertilizer methods. The 1887 volume increased to 77 pages and included methods for butter (9), milk ( 10), and cattle foods (7). Some of these methods have stood the test of time and the broad principles are still used. The 1888 bulletin, 94 pages long, included commercial fertilizers, cattle foods, dairy products, and fermented liquors. In 1890, the manual was up to 200 pages of methods and "proceedings," including methods for sugar. In 1899 the AOAC methods publication excluded association proceedings and discussions. It included fertilizers (24 pages), foods, particularly animal (4 pages), soluble carbohydrates (15), dairyproducts (14), fermented and distilled liquors (14), soils (7), ashes (3), and tanning materials (3). In 1902, the provisional food methods
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were issued as a separate bulletin by uSDA's Bureau of Chemistry. In 1907 all methods to date were combined in Bulletin 107 entitled '"Official and Tentative Methods of Analysis of the AOAC." The 1912 revision totaled 272 pages and carried 29 brood topics, 23 of which dealt with food for humans. In 1920, AOAC initiated publication of its official and tentative methods of analysis. This has been continued and by 1945, its sixth edition totaled over 900 pages. Its 9000 copies went all over the world. The most recent (8th) edition, published in 1955, totals 1008 pages. It would have been even larger had not AOAC made extensive use of abbreviations, cross references, and condensed writing. Twelve thousand copies of the 8th edition were printed. It covers 41 subject matter chapters. Included are 103 pages on drugs. Recent additions are chapters on nutritional adjuncts and spectrographic methods. The regular topics include 22 on different broad classes of food products, cosmetics, caustic poisons, insecticides, plants, soils, and fertilizers. Others are enzymes, coloring matters, metals and spray residues, preservatives and other chemicals, radioactivity, microbiological methods, microphemical methods, extraneous contaminating material in foods and drugs, and standard solutions.
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Relations with Related Organizations
AOAC deals only with methods of analysis. Matters involving legislation, definitions, administrative policy, and interpretation of laws are dealt with by other related organizations: Association of Food and Drug Officials of the United States, Association of American Fertilizer Control Officials, Association of American Feed Control Officials, and Association of American Pesticide Control Officials. AOAC maintains formal and informal cooperative arrangements with other scientific societies dealing with methods of analysis. Included are: American Public Health Association (dairy products), American Oil Chemists' Society (crude fiber, fats, and oils), American Society of Brewing Chemists (malt beverages), Joint
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M a n y AOAC methods have been made an integral part of the standards of food identity. These include cacao products (fat and shell), macaroni (total solids), flours (ash, protein, moisture, carbon dioxide), cream (fat), evaporated milk (fat, total solids), sweetened condensed milk (fat), hard and soft cheeses (moisture, f a t ) , jams, jellies, and fruit butters (soluble solids), egg products (total solids), and tomato products (total solids, s a l t ) . In addition, because both commercial and regulatory chemists generally use AOAC methods, when court cases arise, there is much less likelihood of arguments concerning the best methods; AOAC methods are accepted as best.
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APΡΑRΑTUS
BRUNSWICK,
N.
i.
For further information, circle number 26-1 on Readers' Service Card, page 89 A
A n i m a l balance
by Model 730
mm
ONLY
$34.80 W ^ T
List Price
W / O ATTACHMENT WEIGHTS
CAPACITY 2610 Gram SENSITIVITY 0.1 Gram
ATTACHMENT WEIGHT SET # 7 0 7 This h a n d y w e i g h t r a c k fits under base o f scale. Extends capacity to 2 6 1 0 G r a m . J 5 QO List p r î c e
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OHAUS
SCALE
CORPORATION
1050 COMMERCE AVE. UNION, NEW JERSEY
For further infonnation, circle number 26-2 on Readers' Service Card, page 89 A 26 A
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ANALYTICAL CHEMISTRY
In spite of the tremendous progress made in the past 75 years, the problems ahead m a y dwarf those encountered to date. These lie in two principal areas: pesticide residues and food additives. Reason for the pesticide residue problem is evident when it is recalled t h a t prior to World W a r I I there were no synthetic organic pesticides. Starting with the development of D D T , growth of organic pesticides has been explosive. There are probably 300 now used in production, storage, and t r a n s portation of agricultural commodities. Pesticide Residues. The Pesticide Chemicals Amendment to the Federal Food, Drug, and Cosmetic Act, often called the Miller Amendment, became law in July 1954. Prior to ' this time, the levels of pesticide residues which could be tolerated safely in or on crops were determined by the Department of Health, Education, and Welfare. This was done by means of public hearings to determine whether use of a pesticide was necessary to production or handling of a crop and, if so, to determine a safe level of residue. The Miller Amendment assigns the agricultural functions, to the
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TRITIUM MONITOR MODEL T S M - 9 1
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• Connections for external recorder • Automatic signal alarm • Includes "sniffer" hose attachment • Portable . . . weighs only 12 pounds
For additional information write For bulletin TSM-91 Ε
ΑTΟMIC accessories inc. 2 4 4 - 0 2 J A M A I C A AVE. BELLEROSE 2 6 , Ν . Υ. Represented Nationally by A T O M I C ASSOCIATES, I N C . In C a n a d a : Radionics, Ltd. Circle No. 28 on Readers' Service Card, page 89 A
28 A
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ANALYTICAL CHEMISTRY
REPORT FOR ANALYTICAL CHEMISTS D e p a r t m e n t of Agriculture and the health functions to the D e p a r t m e n t of Health, Education, and Welfare (Food and D r u g Administration). This law prohibits marketing of raw agricultural commodities which bear pesticide chemical residues un less t h e pesticide is recognized as safe; or t h a t adequate scientific evidence exists to establish a safe tolerance; and t h a t the residues remaining are within the safe tol erance level. The D e p a r t m e n t of Agriculture certifies t h a t t h e chemical is useful and the Food and D r u g Administra tion determines safe residue levels. Much of t h e burden of furnishing scientific evidence is placed on t h e manufacturer. USDA's function, therefore, is to determine whether a pesticide is effective a t t h e application r a t e specified. F D A , on the other hand, determines whether residues, if any, constitute a health hazard. Since F D A has to consider other possible sources of t h e same a n d other resi dues from other crops and sources, F D A ' s responsibilities are broad. Once F D A has established a tol erance, which in some cases is zero, AOAC's job is to develop analytical methods to test products for resi dues in the amounts specified. T h e problems in this area a r e great. One illustration is a certain sys temic organic phosphate pesticide which undergoes a change in com position as a result of plant m e tabolism. T h e product resulting may have greater or less toxicity, but in any event is a different com pound. Food Additives. T h e Food A d ditives Amendment of 1958, which becomes effective M a r c h 5, 1959, "prohibits t h e use in food of addi tives which have n o t been ade quately tested to establish their safety." F D A will establish regulations concerning specific additives on t h e basis of scientific evidence estab lished b y its own scientists. T h e problem is complicated in t h a t in terests of several other government agencies are involved. The D e p a r t ment of Agriculture, for example, is responsible for administration of the meat inspection and poultry products inspection laws; t h e Al cohol T a x Unit is concerned with
alcoholic beverages; and the Atomic Energy Commission h a s interest in use of fission and fusion products in production of foods. The person wishing t o use an ad ditive must identify t h e material, the amount t o be added a n d its conversion products in food, and a practicable method for determin ing the quantity of the additive and its conversion products, if any. Ap proval of use requires animal ex perimentation to determine possible acute a n d chronic toxicity. I n these cases, an analytical method of the desired sensitivity and reliability becomes of major interest. Such methods frequently will require accuracies on the order of 1 p.p.m. Food packaging mate rials, such as can liners, present a problem of possible incidental a d ditives. This presents a complex analytical problem due to the small amounts of m a n y constituents which would conceivably be t r a n s ferred to food. In short, the analytical problems in these two areas alone a r e suf ficient to challenge t h e best efforts of t h e analytical chemist for years to come. Conclusion
Development of accurate and rapid analytical methods in t h e field of foods, drugs, cosmetics, feeds, pesticides, plants, and caustic poisons is an important element in the protection of t h e consumer. Improvement of federal a n d state laws and regulations in these fields without standard reference methods would be well nigh impossible. The AOAC is proud of its contri butions over t h e past 75 years t o the development of analytical meth ods for use in t h e wide variety of fields cited above. The tremendous number and v a riety of analytical problems posed by the enactment of t h e Pesticide Chemicals Amendment to the Fed eral Food, Drug, and Cosmetic Act (Miller Amendment) and t h e Food Additives Amendment of 1958 will require major continuing work by AOAC/ chemists for years to come. L i t e r a t u r e Cited
(1) White, W. B., Food Drug Cosmetic Law J. 12, No. 6 (June 1957). AOAC Methods of Analysis.
