FISHERIES AND MARINE SERVICE. An experimental study on the after-effects of feeding rats some types of canned fish

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1 t FISHERIES AND MARINE SERVICE Translation Series No An experimental study on the after-effects of feeding rats some types of canned fish by I.M. Neiman, M.M. Andrianova, A.A. Beloshapko, G.M. Gortalum, N.V. Kolosnitsyna, and M.A. Finogenova Original title: Izuchenie v eksperimente posledstvii skarmlivaniya krysam nekotorykh vidov rybnykh konservov From: Vopr. Pitan. (5): 60-67, 1978 Translated by the Translation Bureau (JN) Multilingual Services Division Department of the Secretary of State of Canada Department of the Environment Fisheries and Marine Service Halifax Laboratory Halifax, N. S pages typescript

2 DEPARTMENT OF THE SECRETARY OF STATE TRANSLATION BUREAU MULTILINGUAL SERVICES DIVISION,;ffee eierd CANADA SECRÉTARIAT D'ÉTAT BUREAU DES TRADUCTIONS DIVISION DES SERVICES MULTILINGUES TRANSLATED FROM - TRADUCTION DE AUTHOR - AUTEUR Russian INTO - EN English I. M. Neiman, M. M. Andrianova, A. A. Beloshapko, G. M. Gortalum, N. V. Kolosnitsyna and M. A. Finogenova TITLE IN ENGLISH - TITRE ANGLAIS An experimental study on the after-effects of feeding rats some types of canned fish 7 11 TITLE IN FOREIGN LANGUAGE (TRANSLITERATE FOREIGN CHARACTERS) TITRE EN LANGUE ÉTRANGÉRE (TRANSCRIRE EN CARACTÉRES ROMAINS) Izuchenie v éksperimente posledstvii skarmlivaniya krysam nekotorykh vidov rybnykh konservov. REFERENCE IN FOREIGN LANGUAGE (NAME OF BOOK OR PUBLICATION) IN FULL. TRANSLITERATE,FOREIGN CHARACTERS. RÉFÉRENCE EN LANGUE ÉTRANGÉRE (NOM DU LIVRE OU PUBLICATION), U COMPLET, TRANSCRIRE EN CARACTÉRES ROMAINS. Voprosy Pitaniya REFERENCE IN ENGLISH - RÉFÉRENCE EN ANGLAIS Problems in Nutrition PUBLISHER - ÉDITEUR PLACE OF PUBLICATION LIEU DE PUBLICATION Not given Not given (USSR) YEAR ANNÉE DATE OF PUBLICATION DATE DE PUBLICATION VOLUME ISSUE NO. NUMÉR O PAGE NUMBERS IN ORIGINAL NUMÉROS DES PAGES DANS L'ORIGINAL NUMBER OF TYPED PAGES NOMBRE DE PAGES DACTYLOGRAPHIÉES 21 REQUESTING DEPARTMENT TRANSLATION BUREAU NO. DFE MINISTÉRE-CLIENT NOTRE DOSSIER NO BRANCH OR DIVISION TRANSLATOR (INITIALS) DIRECTION OU DIVISION Fisheries TRADUCTEUR (INITIALES) J. N. PERSON REQUESTING DEMANDÉ PAR YOUR NUMBER VOTRE DOSSIER N Dr. R. G. Ackman DATE OF REQUEST 7 march 1979 DATE DE LA DEMANDE UNEDITED TRANSLATION For information only TRADUCTION NON KNISH Informa ion set.sierwant Aeri AVR SOS (REV. 2/68)

3 , :Seretary.11fw *, of State Secrétariat d'état MULTILINGUAL SERVICES DIVISION TRANSLATION BUREAU DIVISION DES SERVICES MULTILINGUES BUREAU DES TRADUCTIONS Client's No. No du client Department Ministère Division/Branch Division/Direction Ciw Ville DFE Sc. Info. & Pub. Br. Fisheries Ottawa,--- Bureau No. No du bureau Umeage Langue Translator (Initials) Traducteur (Initiales) Russian J. N. 2',', 1,1, (7.) -b. c Y.) cr'.. u Z 6 0 ;jo < Ce I z 0 "7: 11.2 f: 1 w n c Voprosy Pitaniya (Problems of Nutrition), 1978, No. 5, pp UDC I Izuchenie v dksperimente posledstvli skarmlivaniya krysam 60* nekotorykh vidov rybnykh konservov An experimental study on the after-effects of feeding rats some types of canned fish By: I. M. Neiman, M. M. Andrianova, A. A. Beloshapko, G. M. Gortalum, N. V. Kolosnitsyna and M. A. Finogenova. Institute of Nutrition of the Academy of Medical Sciences of the USSR, Moscow. According to the literature data, in the muscle tissue and in the internal organs of marine and river-dwelling fishes there may be contained polycyclic aromatic hydrocarbons, in particular benzopyrene (BP), which enter the organisms of these fishes from the aquatic biotope, that serves them as food, and from ingested planktonic ooze (1-5). * The numbers in the right-hand margin indicate the corresponding pages in the original text (Tr.). SEC 5-25 (Rev. 6/78)

4 2 Dimethylnitrosamine and diethylnitrosamine have also been found in fishes, as well as microbes which convert nitrates into nitrites, which might lead to an endogenous synthesis of carcinogenic nitroso-compounds (6-8). The technological processing of the fish should attract even greater attention, especially smoking and frying. It has been proven (9) that cod, mackerel and redfish, subjected to hot smoking with wood smoke, contain more than 10 times more BP than does the same fish after processing with cold smoke from shavings or with a curing fluid. There are numerous reports concerning the presence of carcinogenic nitroso-compounds in smoked fish and also in cold-smoked mackerel which has been stored for a long time. It is probable that it is the nitro-gases of technological smoke that are the nitrosifying component in the smoking of fish (10-12). Also attracting attention to itself is the possibility of the contamination of canned fish products by the addition to these of sunflower oil. The formation of BP in sunflower seeds when the latter are dried is knolim (13). Furthermore, for the purpose of sterilization the oil is subjected to considerable heating and when this is done, as has been shown by several studies (14-18), there are synthesized various chemical, still not fully identified, carcinogenic compounds. It seems quite probable that the presence of carcinogenic substances in canned fish products is basically associated with an imperfect, from the hygienic aspect,

5 3 technological preparation of the canned products. It is quite possible that the content of nitroso-compounds in these products increases with prolonged storage of the fish. Proceeding on the basis of the above, and in accordance with the Ministry of Fisheries of the USSR, there were selected for study three kinds of canned fish products, differing as to their technology of processing, namely: "Scad* in tomato sauce" of the Azov-Black-Sea Fish-Canning Combine in Belgorod-Dnestrovskiy, "Kilka prepared in tomato sauce"** of the Astrakhan Fish Combine and "Sprats in oil" of the Riga Sardine Plant, and also two kinds of frying oil used for the preparation of the scad and kilka, which subsequently will be designated, respectively, as "Scad", "Kilka", "Sprats", "scad" oil and "kilka" oil. The "Scad" canned product was prepared in the following manner. The fish were fried in vegetable oil at e for 7-10 minutes depending on their size. After frying the fish were placed into the cans and the tomato sauce was poured in over them, then the cans were closed and sterilized in an autoclave. In contrast to the scad, the kilka were not eviscerated but were placed into the cans whole, with their internal organs. The frying oil is subjected to repeated overheating. Once a week the oil is poured off into storage containers Translator's notes. * - Despite the authors' own translation ("herring" in the English summary), "stavrida atlanticheskaya" is the East Atlantic scad or horsemackerel (Trachurus trachurus). ** - Though "kil'ka" may also be translated as sprat, "kilka" is retained here to differentiate this from "shproty" =sprats. Probably refers to Clupeonella delicatula caspia.

6 4 and left to settle for one day, after which the upper layers of the oil are used again, with the addition of fresh oil. The content of oxidized substances in the frying oil is limited to 1%. Unfortunately, there has not yet been elaborated an express-method for the determination of the oxidized substances in the oil, which would permit one to carry out daily assays of the oil used. The principal danger with respect to the contamination by carcinogens of the sprats lies In the smoking of the latter with hot smoke, containing both nitrogases and BP. Before it is poured onto the sprats in the cans the vegetable oil is sterilized by heating to 1200 for 30 minutes. To resolve the questions that we set, we took into consideration the presence of BP and nitrosamines in the studied canned products and in the oil, the development of tumours in rats when these were fed the studied products or when samples of the frying oil were injected subdermally to the rats, and we also determined the possible co-carcinogenic effect of the frying oil in experiments with the induction of skin tumours in mice with the application of BP. In Table 1 there are presented the results of the determinations of the contents of BP and nitroso-compounds in the studied products 1. 1V1 ethodology. The direct determination of the possible carcinogenic effect of the studied products was carried out during by feeding these products to 1 The authors express their sincere gratitude to P. P. Dikun and Yu. M. Kann for the data that were made available.

7 5 non-pedigree rats (40-45 males and females in each series) daily during the course of the whole experiment (3 years). For the animals which received the canned products the ration was balanced with respect to the protein (up to 20%) by decreasing the amount of oats, containing plant protein. From the canned products the rats obtained 50% of the proteins and 30% of the fats of their total content in the ration. Daily the experimental rats obtained 17.5 g of the studied canned products in addition to their usual vivarium ration (19, 20). The animals of the 1st group (86 rats) received "Scad", of the 2nd group (76 rats) - "Kilka", of the 3rd group (85 rats) - "Sprats", while the rats of the 4th group (control, 70 rats) were kept on the usual vivarium ration. The rats were accommodated in the vivarium, with 6 rats to a cage. Every month the rats were weighed and notes were made on their general state and numbers that had died. Once a week the rats were palpated to reveal any tumours. All of the rats that died were subjected to a thorough pathological and anatomical analysis and also, when necessary, to a histological analysis. Results. The experimental animals readily consumed the studied canned products. Their survival rate and weight gains were the same in the experimental and control groups throughout the course of the whole experiment. In both the control and the experimental rats there were found tumours of varied positioning and structure. Spontaneous development of tumours was noted much more frequently in the females, mainly on account of tumours of the mammary gland.

8 ' 6 Table 1. Contents of BP and nitroso-compounds (in mcg/kg) in the canned products and in the frying oil. Ta 6.natta 1 Cos,ernaamie EH H myrpoaocoe,auffeaaii (a MKI/KT) s aoacepaax H 13 ogaiapovaord macne Product ripozwer a «Oraapaaa» (cymmapxo pm6a maeno) b «KHJIBKa» «1.1.1rtpone U Niacno «czaapagen» e.» «KHJIbItH» Eu BP 0,41 0,08 1,6 3,7 2,1 poimevu1iuttpo3a- Anarietnirtpoaa- Deâ Dem : 6,0 He o6tiappaee. 10,0 15,0 we He o6napywen. C..neRbi fl pumenan il e. 2-.1anpona:1utTp03amaa /016Fra1airrpo3arem B Hcc.ne,twerAkix.." 136pa3u,ax ne o6hapy)kelm. Efl onpegensunt etomatteetleirrtio-cnewrpanbilum meroaom, rpo3ammiaz ruoxpomarorpaclemecicam. a - "Scad" (fish and oil together) b "Kilka" c - "Sprats" d - "Scad" oil e - "Kilka" oil * - Not found ** - Traces Note. Dipropylnitrosamine and dibutylnitrosamine were not found In the studied samples. BP was determined by a luminescent-spectral method, while the nitrosamines were determined by a gas chromatographie method. In the rats that received "Scad" there were found mainly tumours of the mammary-gland: benign,. (in 1 adenoma, in 2 fibroadenoma) and malignant (adenocarcinomas). Moreover, there was found a spindle-cell sarcoma of the sub-cutaneous cellular tissue. Among the 85 rats which survived to the

9 7 appearance of the first tumour, neoplasms were found in 12 (14.1%) of the rats: in 9 (10.6%) the tumours were malignant and in 3 (3.5%) they were benign. Multiple tumours were found in 3 rats (in 3.5% of the total number of rats and 6.8% of the number of females). Metastases were not found. All of the tumours were in the females. A different picture was observed in the rats which received "Kilka". Among the 73 animals which lived to the appearance of the first tumour, neoplasms were found in 17 (23.3%), of which number 15 rats (20.5%) had malignant neoplasms (mainly adenocarcinomas of the mammary glands, and also sarcomas of various localization, carcinoma of the thyroid gland, liver, skin and cymbal gland*), while 2 rats (2.7%) had benign tumours (fibroadenomas of the mammary gland). In this group there were 39 females and 34 males. Tumours were found in 12 (30.8%) of the females, of which number 10 (25.6%) had malignant tumours and 2 (5.1%) had benign tumours. In 5 of the males there were found malignant tumours, but no benign tumours were found. Multiple tumours appeared in 6 (8.3%) of the rats. Metastases were noted in 1 rat. Among the 82 rats which received "Sprats" and survived to the appearance of the first tumour neoplasms were found in 18 (22%); in this case malignant tumours (sarcomas of different structure and various localization, adenocareinomas of the mammary gland, carcinoma of the stomach, liver, lung and cymbal gland) were found in 16 (19.5%) and benign tumours (adenomas ofthe mammary gland) in 2 (2.4%) of the rats. In * Translator's note. "tsymbalovaya zheleza" - here translated as "cymbal gland", since I was unable to identify this more precisely.

10 8 this group there were 43 females and 39 males. In 15 (34.9%) of the females there were found tumours, of which number there were malignant tumours in 13 (30.2%) and benign tumours in 2 (4.6%) of the females. Malignant tumours were found in 3 of the males, benign tumours were not found in the males. Multiple tumours were noted in 7 (8.5%) of the rats, metastasized tumours were found in 2 rats. For comparison it is necessary to present the data from the control group of animais, in which tumours arose spontaneously. Among the 67 rats which survived to the appearance of the first tumour, neoplasms were found in 11 (16.4%); malignant tumours in 4 (6%), benign tumours in 7 (10.4%). Among the malignant tumours were adenocarcinomas of the mammary gland, carcinoma of the cymbal gland and fibrosarcoma of the ovary; among the benign tumours were adenomas and fibroadenomas ofthemammarygland, adenoma of the salivary glands and lipoma. In this group there were 34 females and 33 males. In 10 (29.4%) of the females there were found tumours, including malignant tumours in 3 (8.8%) and-benign tumours in 7 (20.6%). Only in 1 male (3%) was there noted a malignant tumour, adenocarcinoma ofthemamiiiary gland. Multiple tumours were found in 4 (6%) of the rats. Metastasized tumours were not found. In evaluating the carcinogenic effect of the studied substances we decided to be guided by the following criteria (18); 1) a significant (authentic) increase in the number of one kind of tumour or other in comparison with the number of these in the control; 2) the appearance of tumours of a

11 9 different type than in the control; 3) a decrease in the latent period in comparison with that in the control; 4) an increase in the number of tumours in an individual rat. goes without saying that of special significance is a predominance of malignant tumours, in comparison with the control. The data obtained by us indicate a significant increase in the number of malignant tumours in the animals that - received the "Kilka" and "Sprats" canned products: respective- ly In 20.5% and 19.5% of the animals, as compared to 6% in the control group (P <0.02 in both cases). It In these experimental animals we found mainly tumours of the internal organs and skin. Thus, in the group of rats that received the "Kilka" canned products there were found tumours which were not found in the animals of the control group: sarcomas (round cell and spindle cell), rhabdomyosarcoma, carcinoma of the thyroid gland, squamous cell carcinoma of the skin, carcinoma of the sebaceous glands, carcinoma of the large intestine and hepatic cell carcinoma. In the group of rats that received the "Sprats" canned products there were found tumours which were not found in the animals of the control group: sarcomas (polymorphous cell and spindle cell), hemangiendothelioma of the liver, adenocarcinoma of the stomach, carcinoma of the lungs and hepa- tic cell carcinoma). The average latent period for the development of the tumours in the animals that received the "Kilka" and "Sprats" canned products (1 year and 4 months, and 1 year and 5 months, respectively) was 3-4 months shorter than in the control group (1 year and 8 months; P 4:0.1 9 i.e. there is a distinct

12 tendency, though the difference is not completely significant). Multiple tumours in animals that received the "Kilkau and "Sprats" canned products were encountered more frequently than in the control, though the difference is not significant in this case. Metastasizedtumourswere found in 1 of the rats that received "Kilka" canned products and 2 of the rats that received "Sprats"; no metastasizedtumourswere found in the control. It should be noted that the total number of animals with tumours (benign and malignant) in the groups of rats that received the "Kilka" and "Sprats" canned products with their food, even though greater than in the control (respectively 23.3, 22.0 and 16.4% of the rats), did not differ so very markedly from the total number of animals with tumours in the control. It is very important, however, that the neoplasms in the control, appearing as the result of the inherent tendency of the rats to develop spontaneous tumours, were mainly benign and only a small portion of them became malignant, and at the same time metastases were not found; while among the rats that received the "Kilka" and "Sprats" canned products only a few of the tumours were benign, while the majority of them became malignant during the course of the experiment, under the Influence of the canned products that entered the organism, and in some cases even produced metastases. In the control group the rats with malignant tumours comprised 36%, while among the animals receiving the "Kilka" and "Sprats" canned products the rats with malignant tumours comprised 88 and 89%, respectively (Table 2). 1 0

13 1 1 Table 2. Tumours in rats that received fish canned products with their food a d Onyxo.nu y Kpwc, nonyvaanaix c nnw,eii pw6inze Kcmcepsbr Tadzaita 2 13 A linen tcpuc, C D E F AOXIIBIIIIIX tincno xprec c onyxostanta npanaa, aim «AO thicao nonbneintit Kontigec-rBo Ba tectnetittux Bpbrc c KoacepBu aepaa rt onyx,. Bpbtc c ortyxone0 metac-rauttay, a itamioft ortyxonnme Ao6poBeteCT- B noxagrbe- ec tt cpé,adt Bcex ponabunn tm rt onyxonen onyxonsma rpyne B ENNUI s,, en. mai, «Cimapitaa» (14,1) 3 (3,5) 9 (10,6) 75 0 «KmnbKa» (23,3). 2 (2,7) 15 (20,5) 88 l' 4111npurbi» (22,0) 2 (2,4) 16 (19,5) 89 2 KOHTp0J11, (16,4) 7 (10,4) 4 (6) 36 0 npameganu. e. P npu cpabnetunt c xotitponem <0 02. B ci;o0kax npogewr. A - Canned products a - "Scad" b - "Kilka" o - "Sprats" d - Control B - Number of rats surviving to the appearance of the first tumour in a given group C - Number of rats with tumours D - Number of rats with: ben. - benign tumours mal. - malignant tumours E - Percentage of malignant tumours among all tumours F - Number of rats with metastasized tumours N ote. P in comparison with the control < In parentheses - percentage. Not quite clear is the effect of the "Scad" canned products. In the rats which received these canned products the percentage of malignant tumours amang all of the neoplasms was considerable, though the total number of rats with tumours was small, even smaller than in the control.

14 12 Since the sunflower oil which is added to the fish canned products is subjected to repeated and prolonged heating for the purpose of sterilization, it was natural to check the possible carcinogenic effect of the oil from the "Scad" and "Kilka" canned products. Method o 1 ogy. Throughout the course of the whole experiment 6.1 g of the studied oil (10% of the daily ration (12-15)) was added to the food of the experimental rats each day. 82 rats received the "sicad" oil, 81 rats received the "kilka" oil and 50 rats (control) received fresh sunflower oil in the same quantity. The maintenance of the animals and the observations on them were the same as in the preceding experiment. Results. Among the 77 rats which received the "scad" oil and survived to the appearance of the first tumour neoplasms were found in 8 (10.4%) of the rats, of which all were malignant (sarcomas, adenocarcinoma of the stomach, adenocarcinoma of the mammary gland, carcinoma of the cymbal gland). In this group there were 38 females and 39 males. Tumours were found in 6 (15.8%) of the females and in 2 (5.1%) of the males. Multiple tumours were found in 2 rats. 1 tumour metastasized. Among the 83 rats which received the "kilka" oil and survived to the appearance of the first tumour neoplasms were found in 11 (13.3%) of the rats, of which number 10 (12%) had malignant tumours, while 1 (1.3%) had benign tumours. In this group there were 45 females and 38 males. In 10 (22.2%) of the females there were diagnosed tumours, of which number

15 13 9 (20%) had malignant tumours (adenocarcinomas of the mammary gland, sarcomas of various structure and localization, carcinoma of the liver, malignant neurinoma of the stomach), while 1 (2.2%) had a benign tumour (cyst of the small intestine). Only one malignant tumour developed in a male (2.6%), and no benign neoplasms were found in the males. Multiple tumours in this group were found in 6 (7.2%) of the rats. One tumour metastasized. Among the 47 control rats, which received fresh sunflower oil with their food and which survived to the appearance of the first tumour, in 4 (8.5%) of the animals there appeared tumours, in all of these rats these were malignant (adenocareinomas of the mammary gland, carcinoma of the kidney, lymphocarcinoma of the spleen, angiosarcoma). In this group there were 16 females and 31 males. Tumours were found in 3 (18.8%) of the females and in 1 (3.2%) of the males. Multiple tumours were noted in 2 rats. Metastases were not found. It is evident that it was not possible to note a significant increase in the number of all tumours and, in particular, of the malignant tumours in the rats that received the frying oil with their food, although a certain tendency in this direction is apparent (10.4 and 12.0% malignant tumours in the groups of rats that received the "scad" oil and the "kilka" oil, with 8.5% in the control). Furthermore, in the experimental rats there appeared tumours of a different type than in the control, and some of these metastasized in contrast to the controls, but with the total small number of

16 Table 3. Tumours in rats that received frying oil from the canned products with their food. _. Ta6,nulta 3 a o Onyxonu y Kpbrc, Tio,nriaswax c nnatert o5aaviinioe maul() H3 KOHCepB013 A. a. lincno sipmc, B Konsinec -rso Kpbic c onyxonsi- P.. AO>K11 El /II II X AO... 4 HCJIO Kpbic c nommeraist x.oramecrbo metactaarippo- Ilpoitywr nepnoil onyx. Kpble c MIMI! jnt Product g Au/Ewa onyxonnbni.06poseasiecr-. 3noKanectami-,onyxonsibisi. rpynne be 11111DIMIri libimh '.. ben. mal. lgac.lo «ctattpubi» (10,4). 0 8 (10,4). Mac.lo (KH,71b101) 83 ' 11 (13,3) 1(1,3) c 10,(12,0) Cae Kee macno norcon-,.hetnioe (KpHTpOlib) 47 4 (8,5) 0 4 (8,5), p menane e. eicoftax nponewr. a - "Scad" oil b "Kilka" oil c - Fresh sunflower oil (control) A - Number or rats surviving to the appearance of the first tumour in a given group B - Number of rats with tumours C - Number of rats withs ben. - benign tumours mal. - malignant tumours D - Number of rats with metastasized tumours N ote. In parentheses - percentage. tumours there are insufficient grounds for making any conclusion as to the carcinogenicity of the frying oil. It is interesting to note that in both the experimental and the control rats almost all of the tumours were malignant, although, because of the quantitatively inadequate material, it is not possible to draw any general conclusions from this (Table 3).

17 15 Me t h od o I ogy. In each group there were 50 rats of both sexes. The studied oil, sterilized in a boiling water bath, was administered to the rats twice, with an interval of 3 months, at a dose of lml subcutaneously into the left inguinal fold. The animals of the 1st group received "scad" oil, of the 2nd group - "kilka" oil, and of the 3rd group - fresh sunflower oil. The observations on the rats were conducted in the same way as in the preceding series. The survival rate of the rats and their weight gain during the course of this experiment were the same in all groups. We also carried out an investigation of subcutaneous administration to the rats of of the same samples of oil. Results. In the group of animals which received the "scad" oil, among the 50 rats that survived to the appearance of the first tumour, neoplasms were found in 5 (10%) of the rats; all of these were malignant (adenocarcinoma of the mammary gland, adenocarcinoma of the large intestine, carcinoma of the skin, spindle cell sarcoma, lymphosarcoma of the spleen). In this group there were 27 females and 23 males. A tumour was found in 1 (3.7%) of the females and these were also present in 4 (17.4%) of the males. Multiple tumours were found in 1 (2%) of the rats. Metastasized tumours were found in 2 rats. In the group of rats which received the "kilka" oil, among the 44 animals that survived up to the appearance of the first tumour, neoplasms were found in 4 (9%) rats, in 3 (6.8%) these were malignant (adenocarcinomas of the mammary gland, lymphosarcoma of the small intestine) and in 1 (2.3%)

18 16 - benign (lipoma). In this group there were 18 females and 26 males. All of the tumours were found in females (22.2%). Multiple tumours were found in 1 (2.3%) of the rats. Metastases were not found. In the control group, among the 50 rats that survived 66 to the appearance of the first tumour, neoplasms were found in 3 (6%); all were malignant. In this group there were 29 females and 21 males. Tumours were found only in the females (10.3%). Multiple tumours were not found. A metastasized tumour was found in 1 rat. In none of the groups was there found an occurrence of tumours at the site of injection of the oil. These experiments with the parenteral administration of the frying oil to the rats also did not eve convincing evidence of carcinogenicity of the studied samples, since the difference in the frequency of the malignant tumours (10% in the group of rats that received "scad" oil, 6.8% in the group of rats that received "kilka" oil, and 6% in the control) was statistically insignificant. In order to study the possible cocarcinogenic properties of the studied samples of canned products and frying oil we carried out the following experiments on mice of the CBAX C57B1 line of both sexes withan initial weight of g. Methodology. Daily there was added to the vivarium ration of the mice 6 g of the studied canned products (at the expense of a decrease in the amount of oats, see above) or 2 g per mouse of the frying oil (log of the daily ration). 1* months after the commencement of the feeding of the studied

19 1 7 products to the rats we started to apply, once each week, a dose of 0.02 ml of 0.6% benzol solution of BP onto the skin of the mice, and then continued these applications up to the end of the observations, i.e. to the 28th week of the experiment. We determined the times of the appearance of the first papilloma, the average latent period of its development and the percentage of mice with carcinomas by the 28th week of the experiment. Results The first papilloma appeared on the 12th and 13th weeks in 50 experimental and 45 control mice. The data on the average latent period of development of the papillomas and on the percentage of mice with malignant papillomas indicate that there is no significant difference in these indices between the experimental and the control mice. There was noted only a slight shortening (by weeks) of the average latent period of development of the papillomas in the experimental mice. The survival rate of the mice in the experimental groups and the control were the same. It is evident that the feeding to the mice of the studied samples of the canned products and frying oil did not have any significant effect on the development of B?-induced skin tumours in these mice. Similar data were obtained also with parenteral administration (subcutaneous) of the frying oil to the mice and the application of BP onto the skin of these mice. In this experiment also there were no cases of the appearance of tumours at the site of the injection of the oil. No cocarcinogenic activity was manifested; there was even noted a weak

20 A 18 tendency for the development of the induced tumours to be retarded. Without considering the obtained data as demonstrating a carcinogenic activity of the studied samples of the frying oil, we should nevertheless emphasize the presence in them of a modifying effect on the spontaneous and induced carcinogenesis which is distinctly manifested in the experiments on the rats. One should also not forget the presence in the studied samples of frying oil of a fairly considerable (see Table 1) content of BP (especially in the "scad" oil). Cone lus ion. When rats were fed for 3 years on the "Scad", "Kilka" and "Sprats" canned products it was noted that in the animals that were fed the "Kilka" and "Sprats" canned products there appeared more malignant tumours than in the control rats and the rats that received the "Sead" canned product, and in this case the difference was statistically significant: among the rats receiving "Kilka" tumours appeared in 20.5% of the animals, among those receiving "Sprats" - in 19.5%, while among the control rats - in 6% and among those receiving the "Scad" canned product - in 10.6%) (P <0.02 in the case of the comparison of the first two indices with the control). Feeding the rats the frying oil of the "Scad" and "Kilka" canned products led only to a slight, statistically insignificant, increase in the frequency of development of tumours. The administration to mice of the tested canned products and oil samples, with their food or parenterally, had only a weak effect on the development in these mice of skin tumours induced by BP.

21 1 9 BP and carcinogenic nitroso-compounds were found in the studied canned products, especially in the "Kilka" and "Sprats". A review of the presently employed technology for the preparation of fish canned products is recommended. JIHTEPATYPA. 1. Scaccini A., Scaccini-Cicatelli M. - Rapp. Comm. Intern. Mer. Medit., 1969, v. 19, p An delman I., Suess M. B1OJIJI. B03, 1971, T. 43,c Foptanym r. M.,.CmHpaona IL' n. B Hexotopue Hun% angel-ma aarpnanemin inteunieri cpeau xanneporemmui newectnabui. M., 1972, c Tay c 0. B., Kann 10. M., K a c K. A. - B C6oplimc crater( no xnuat H xnamemaii Texuo.norint. (Bain. 34). Texaononta nantenbtx npora- DUCTS. (IV). Tanana, 1974, C r op t anybt r. M. B KH.: 3KCHepliMeHT2.71b- Han H manatleckaa owto.tiontg. TaznaH, 1975, Bain. 2, c F en g Y. Y., W E. O. F. - Lancet, 1971, v. 2, p Fazio T D am leo I. N., Howar d L W. et al. - J. Agile. Food Chem, 1971, v. 19, p Howard I. W., Fazio T., Watt es I J. Ass. off. Analyt. Chem, 1970, v. 53, p RHay a II. IL KpacinigKasi H.,11., 111 e H.aHraes a H. A. H - Bonp. onaon 1969,. M 4, c KaatteporeHHue N-HHTp030C0e.r(HHeHan - RerICTISHe, CHHTC3, onpeaenenne. Tax- Jinn, To we. Tax,-rea, Working Conference on Environmental. N-nitroso Compounds Analysis and Formation Proceedings Lyon, Agency for Reserch on Cancer. Ed. P. Bogovski, E. A. Walker. Lyon, K a Jui H H - H a 14. A. - Bonp. Harm., 1969, M.11., c H e fi rd a H H. M. Kanueporeabt runuende npuyatia. M., B ai tu ecaanoaa M. Z. - Blom. aunep. 1967, N2 5, c Baiui eciaaona M. g. -- Bonp. I-n=11m, 1968, N9 3, c B mecaan o Ba M Boap. ohaon., N2 4, c B bi mecna Bs) - la a M. g. - Becta. AMH CCCP, 1972, M 2, c anta.nb.% 0 - B a 3. M. - B KH.: CIDe3):( nultemicros H caahraphux epatieet rpyarda Matepnaebt. T6H.nacH, 1969, c Kama a bahhona 3. M. TitrHeantiecaoe }ingenue Rpm- HapHo norrotonaenalzx npoltyatob wh3othor0 npoacxowneahh, ncomeprityrux B03,LIefiCTH8I0. ramma-o6aretam c II,C.11b10 y.jutln Hun cpokos ax xpaaeahh. Antopecp. JI,HC. Kale. M., flocrymina 711V 1977 r. 1. M. Neiman, M. M. Andricnoza, A. A. Beloshapko, G. M. Gortalum, N. V. Kolosnitsyna, M. A. Finogenoua - AN EXPERIMENTAL STUDY ON THE AFTER-EFFECTS Of,EDING-Rf'..TS -ON SOME= 7'17E3 OF FISH G=ANNED GOODS Summar y. For 3 year fish canned goods were added to the ration of rats. These additions included atlantic herring in tomato gravy ("Stavrida"), dressed sprat in tomato gravy (sprats-small-sized) or sprat in vegetable oil ("Sprat"). Rats receiving can-. ned "small-sized sprats" or "sprats developed much more often malignant tumours of different localization than did the animals fed on "Stavrida" or control rats. Feeding of rats on the vegetable oil from "stavrida" and "sprat" cans did not have any material effect on the development of tumours. Introduction of these samples of oil together with the food or parenterally to mice did not have any substantial influence on the development in them of skin tumors, induced with benzpyrene. The canned goods under investigation,' especially of the "sprat" kinds, demonstrated small amounts of benzpyrene and carcinogenic nitroso-compounds.

22 20 REFERENCES 2. Andelman I. and Suess M. - Bulletin of the World Health Organization, 1971, vol. 43, p Gortalum G. M. and Smirnova L. P. - In the books Some results of the study of environmental contamination by carcinogenic substances. Moscow, 1972, P Tauts O. V., Kann Yu. M. and Kask K. A. - In the book: Sbornik state' po khimii I khimicheskoi tekhnologii. (Vyp. 34). Tekhnologiya pishchevykh proizvodstv. (Symposium of papers on chemistry and chemical technology. (No. 34). Technology of food products.) (IV). Tallin, 1974, p Gortalum G. M. - In the book: Experimental and clinical oncology. Tallin, 1975, no. 2, p Dikun P. P., Krasnitskaya N. D., Shendigaeva I. A. et al. Voprosy onkologii (Problems in oncology), 1969, no. 4, p Kantserogennye N-nitrozosoedineniya deistvie, sintez, opredelenie. (Carcinogenic N-nitroso-compounds - effect, synthesis, determlnation.) Tallin, Ibidem. Tallin, Kallnina I. A. - Voprosy onkologii, 1969, No. 11, p Neiman I. M. - Carcinogens and food products. Moscow, Vysheslavova M. Ya. - Byulleten' éksperimental'nol biologil (Bulletin of Experimental Biology), 1967, no. 5, p. 84.

23 Vysheslavova M. Ya. - Voprosy pitaniya (Problems of Nutrition), 1968, no. 3, p Vysheslavova M. Ya. - Voprosy onkologii (Problems in Oncology), 1969, no. 4, p Vysheslavova M. Ya. Vestnik ANN SSSR (Herald of the Academy of Medical Sciences of the USSR), 1972, no. 2, p Kamal'dinova Z. M. - In the book: S'ezd gigienistov i sanitarnykh vrachei Gruzii Materialy. (Congress of hygienists and public health officers of Georgia. 3rd. Materials). Tbilisi, 1969, p Kamardinova Z. M. - A hygienic study of prepared culinary products of animal origin, subjected to the action of gamma-irradiation with the aim of prolonging the storage time of these products. Author's summary of dissertation for the Candidate's degree. Moscow, Received 7th April 1977.