Document QgbEXaMwkV7x3j4GMMe2p2Zkk
National Cancer Institute
CARCINOGENESIS
Technical Report Series No. 38 1978
BiOASSAY OF
AMClOn 1254 F03 POSSIBLE CAIXliiCSEiilCITY
CAS No. 27323-18-8 NCt-CG-TA-38
U.S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE
Public Health Service
.
National Institutes of Health
HONS 000255
BIOASSAY OF AROCLOR 1254 FOR POSSIBLE CARCINOGENICITY
Carcinogenesis Testing Program Division of Cancer Cause and Prevention
National Cancer Institute National Institutes of Health
fiethesda, Maryland 20014
U.S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE Public Health Service
National Institutes of Health
DHEW Publication No. (NIH) 78-838
HONS 000256
BIOASSAY OF AROCI.OR 1254
FOR POSSIBLE CARC1NOCF.NICITY
'
Carcinogenesis Testing Program Division of Cancer Cause and Prevention
National Cancer Institute National Institutes of Health
CONTRIBUTORS: Thi9 report presents the results of the bioassay of Arocloi^ 1254 for possible carcinogenicity, conducted for the
Carcinogenesis Testing Program, Division of Cancer Cause and Prevention, National Cancer Institute (NCI), Bethesda, Maryland. The bioassay was conducted by Stafford Research Institute, Menlo Pgrk. California, initially under direct contract to NCI and currently under a subcontract to Tracor Jitco, Inc., prime contractor for the NCI Carcinogenesis Testing Program.
The experimental design and doses were determined by Drs. R. R.
Bates*'?, D. C. L. Jone63, D. P. Sasroore3, G. W. Newell3, and R.
M. Elashoff^, and Mr. U. E. Davis3. The principal Investigator
was Dr. D. C. L. Jones; the technical supervisor of animal
treatment, observation, and data handling was Mr. W. E. Davis;
necropsy and tissue fixation were supervised by Dr. D. P.
Sasmore.
.
Histopathologic examinations were performed by Dr. H. Elster5 and
the diagnoses Included in this report represent his
interpretation.
Neoplasms and compound-related hyperplastic
lesions were reviewed by Drs. W. M. Busey and J. F. Hardisty,
who also prepared the interpretive pathology summary Included In
this report.
Animal pathology tables and survival tables were compiled at EC&G
Mason Research Institute?.
The statistical analyses were
performed by Dr. J. R. Joiner, using methods selected for the
bioassay program by Dr. J. J. Gart^. Chemicals used in this
ill HONS 000257
bloassay were analyzed at Stanford Research Institute, and the analytical results were reviewed by Dr. C. W. Jameson.
This report was prepared at Tracor Jitco under the direction of NCI. Those responsible for the report at Tracor Jitco were Dr. Marshall Steinberg, Director of the Bloassay Program; Drs. J. F. Robens and R W. Fogleman, toxicologists; Dr. R. L, Schueler, pathologist; Ms. L. A. Waltz and Mr. W. D. Reichardt, bioscience writers; and Dr. . W. Gunberg, technical editor, assisted by Ms. Y. E. Presley.
The statistical analysis was reviewed by members of the Mathematical Statistics and Applied Mathematics Section of NCI?: Dr. John J. Cart, Mr. Jun-mo Nam, Dr. Hugh M. Pettigrew, and Dr. Robert E. Taronc.
The following other scientists at the National Cancer Institute were responsible for evaluating the bloassay experiment, Interpreting the results, and reporting the findings:
Dr. Kenneth C* Chu Dr. Cipriano Cueto, Jr. Dr. J. Fielding Douglas Dr. Dawn G. Coodman Dr. Richard A. Criesemcr Mr. Harry A. Milman Dr. Thomas W. Orme Dr. Robert A. Squire^ Dr. Jerrold M. Ward
^Carcinogenesis Testing Program, Division of Cancer Cause and Prevention, National Cancer Institute, National Institutes of Health, Bethesda, Maryland.
2Now with the Office of the`Commissioner, Food and Drug Administration, Rockville, Maryland.
^Stanford Research Institute, Menlo Park, California.
iv
HONS 000258
^Department of Biomathematics, Center for the Health Sciences, University of California, Los Angeles, California.
^Department of Pathology, David M. Brotman Memorial Hospital, 3828 Hughes Avenue, Culver City, California.
^Experimental Pathology Laboratories, lnc, P.0. Box 474, Herndon, Virginia.
^EGAG Mason Research Institute, 1530 East Jefferson Street,
Rockville, Maryland.
__ , .........
.......
^Iracor Jltco, Inc., 1776 East Jefferson Street, Rockville, Maryland.
^Mathematical Statistics and Applied Mathematics Section, Biometry Branch, Field Studies and Statistics, Division of Cancer Cause and Prevention, National Cancer Institute, National Institutes of Health, Bethesda, Maryland.
Ityow with the Division of Comparative Medicine, Johns Hopkins University, School of Medicine, Traylor feuilding, Baltimore, Maryland.
v MONS 000259
SUMMARY
A bloaasay of Aroclor* 1254 for possible carcinogenicity was conducted by administering the test chemical In feed to Fischer 344 rats.
Croups of 24 rats of each sex were administered Aroclor 1254 at one of three doses, either 25. 50. or 100 ppm, for 104*105 weeks. Matched controls consisted of groups of 24 untreated rats of each sex. All surviving rats were killed at 104-105 weeks.
Mean body weights of males and females receiving mid and high doses and females receiving low doses of the chemical were
consistently below those of the corresponding controls, beginning at about week 10 of the study. The decrease in survival among males, but not among females, showed a significant dose-related
trend. Adequate numbers of animals of both sexes survived for meaningful statistical analyses of the incidences of tumors.
The combined incidences of lymphomas and leukemias showed a significant dose-related trend in males (controls 3/24, lowdose 2/24, raid-dose 5/24, hlgh-dose 9/24, P - 0.009). However, the direct comparisons of each dosed group with those of the matched controls were not statistically significant, and the tumors cannot clmarly be related to administration of with V-Aroclor* 1254.
Hepatocellular adenomas and carcinomas were found In the dosed groups, but not In the controls (males: mid-dose 1/24, high-dose 3/24; females: mid-dose 1/24, high-dpse 2/24). Additionally, a high incidence of nonneoplastic hyperplastic nodules was noted in the dosed animals (aales: controls 0/24, low-dose 5/24, mid-dose 8/24, hlgh-dose 12/24; females: controls 0/23, low-dose 6/24, mid-dose 9/22, hlgh-dose 17/24). Although the incidences of tumors were not significant, the occurrence of the hyperplastic nodule^ppeared to be related) to administration of the chemical.
/. i lt*' ,l< ^
'lO- 1 no.-"-'
vii
HONS 000260
In the stomach, Jejunum, or cecum, adenocarcinomas were observed in two dosed males and In two dosed females as well as a carcinoma In one dosed male. None of these lesions was found In
control animals In this study. Historical incidences of these tumors at this laboratory (6/600 males (It), 2/600 females 10.31) suggest that the lesions -- although not statistically slaniflcant -- may be related to the administration of Arnrlnr81 1254.
It is concluded that under the conditions of this bloaasay,
Aroclor 1254 was not carcinogenic in Fischer 344 rats;/however,
a high incidence of hepatocellular proliferative lesions in both
male and female rats was related to administration of the
chemical. (M. mdauiaWT^m^rnw^s^f^d^taattdlnitaetlnai
M'lUAliaiMIUlt
mi in?
rrt'ty //<// a SvfV t CdeSi 4+44* I 11 <& ^
Kj
/ft ft**# /GZtz-f.
* W-* *. -I
viii
HONS 000261
TABLE OF CONTENTS
I. Introduction......... .................. .............................................................
1
XI. Materials and Methods........................................... ................. ................
3
A. Chemical......... ........................................................................................... B. Dietary Preparation......................................... ................................ .. C. Animals..................................... D. Animal Maintenance...............
E. Subchronic Studies................................................................................. F. Design of Chronic Studies........................................................... G. Clinical and Pathologic Examinations......................................... H. Data Recording and Statistical Analyses......... ..
3 3 4 5
6 7 7 9
III. Results - Rats..................................................................................................... 15
A. Body Weights and Clinical Signs .................................................
B. Survival......... .............. C. Pathology ................................................................................................... D. Statistical Analyses of Results ........................... .....................
15
15 IB 21
IV. Discussion.....................................................
23
V. Bibliography..............................................................
27
APPENDIXES
Appendix A
Summary of the Incidence of Neoplasms in Rats Fed Aroclor 1254 in the Diet....................................
31
Table A1 .
Summary of the Incidence of Neoplasms in Male Rats Fed Aroclor 1254 in the Diet................
33
Table A2
Summary of the Incidence of Neoplasms in Female Rats Fed Arcelor 1254 in the Diet....................
37
Appendix B
Summary of the Incidence of Nonneoplastic Lesions in Rats Fed Aroclor 1254 in the Diet............
41
Table B1
Summary of the Incidence of Nonneoplastlc Lesions in Male Rats Fed Aroclor 1254 In the Diet............................................................... ...............
43
lx MGNS 000262
Table B2 Appendix C
Table Cl Table C2
Table 1
Figure 1 Figure 2
Page
Summary of the Incidence of Monneoplastlc Lesions in Female Fats Fed Aroclor 1254 In the Diet.......................................................................................
47
Analyses of the Incidence of Primary Tumors In Rats Fed Aroclor 1254 in the Diet.............................
51
Analyses of the Incidence of Primary Tumors in Male Rats Fed Aroclor 1254 in the Diet..................
53
Analyses of the Incidence of Primary Tumors In Female Rats Fed Aroclor 1254 in the Diet..............
57
TABLES
Design of Aroclor 1254 Chronic Feeding Studies in Rats........................ ..........................................
8
FIGURES
Growth Curves for Rats Fed Aroclor 1254 in the Diet.......................................................................................
Survival Curves for Rats Fed Aroclor 1254 in the Diet........rr..................rr;............v
16 17
x MOWS 000263
I. INTRODUCTION
Aroclor (CAS 27323-18-8; NCI C02664) is the registered trademark of the Monsanto Chemical Company for their polychlorinated biphenyls (PCBs). PCBs were developed in 1929 primarily for use as heat transfer fluids and dielectrics (insulators)* Aroclor 1254, a biphenyl containing approximately 54% chlorine. Is a nonflammable heat transfer agent which functions in the range of 250-360C (Hubbard, 1964; Poffenberger and Hubbard, 1965).
PCBs have been used in transformers and capacitors; as Industrial fluids in hydraulic, gas turbine, and vacuum pumps; as lubricants and plasticizers (for flame retardation); and as additives in surface coatings, inks, papers, adhesives, sealants, pesticides, and dyes for carbonless duplicating paper (Hubbard, 1964; Broadhurst, 1972). These compounds tend to accummulate in the biosphere (Flnklea et al., 1972). Because of direct and indirect human and animal exposure, food contamination, and environmental pollution from many of these uses, the marketing of PCBs has been markedly curtailed in recent years (EPA, 1977).
This bioassay of Aroclor 1254 was conducted as a part of a larger study designed to assess the combined effects of a group of known or suspected carcinogens. Only the results of the study of the administration of Aroclor~l254 are reported herein.
1 HONS 000264
II. MATERIALS AND METHODS
A. Chemical
Aroclor 1254 was obtained In a single batch (Lot No. KB01-604) from the Monsanto Chemical Company, St. Louis, Missouri. The Identity and relative purity of the test chemical were confirmed at Stanford Research Institute. Elemental analyses (C, H, Cl) indicated S4.67Z chlorine. Gas-llquld chromatography and mass spectroscopy showed that the Aroclor 1254 contained at least 18 isomers of polychlorinated biphenyls ranging from 4 to 7 chlorine atoms per molecule. Identity was confirmed by nuclear magnetic resonance, infrared, and ultraviolet spectra, which were in agree ment with the structure. No attempt was made to Identify or quantitate impurities.
The chemical was stored at room temperature in 1-gallon amber glass jars.
B. Dietary Preparation
All diets were formulated every 2 weeks using Low Fat Lab Chow (Ralston Purina Co., St. Louis, Mo.). A stock diet was first pre pared by hand mixing a weighed amount of the Aroclor 1254 with corn oil (Staley Manufacturing Co., Orange, Calif.) and adding this mixture to a small amount of feed which was also mixed by
'3
HONS 000265
hand. More corn oil and feed were Chen added co give a final concentration of 3,000 ppm Aroclor 1254 and 3% corn oil and then machine mixed In a Hobart blender for 30 minutes. Each stock diet was analyzed for content of Aroclor 1254 by a method involving extraction, Florisil chromatography, and quantitation by gas-liquid chromatography. Concentrations of 3,000 ppm + 10% were considered acceptable for use In preparing the test diets. Aroclor 1254 at 3,000 ppm in the stock diet was found to be stable when held in rat feeders at-room temperature for..a 2-week period.
To obtain test diets having appropriate concentrations of
Aroclor 1254, the stock diet was diluted, as required, with
control diet containing 3% corn oil and mixed In a Hobart
blender.
The stock and test diets were stored at room
temperature in covered plastic containers.
C Animals
Male and female Fischer 344 rats, obtained through contracts of the Division of Cancer Treatment, National Cancer Institute, were used In these bioassays. The rats were obtained from Simonsen Laboratory, Gilroy, California. On arrival at the laboratory, all anlmalB were quarantined for 2 weeks as an acclimation period. Following this period, all males gaining less than 25
"4 MONS 000266
grams, all females gaining less than 15 grams, and all unhealthy animals were culled. The remaining animals were assigned to cages, one per cage, until each cage contained three animals. Cages were then numbered and assigned to control and treated groups using a computer-generated randomization tabic. Rata were ear-clipped for Individual identification.
D. Animal Maintenance
All animals were housed in temperature- and humidity-controlled rooms. The temperature was maintained at 22C with a range of 21-24C, and the relative humidity was maintained at approxi mately 45t. The room air was changed 10 times per hour and was maintained under positive pressure to the access halls. Fluorescent lighting provided illumination 12 hours per day. Food and water were available ad libitum. Drinking water was softened, filtered, sterilized with ultraviolet light, and supplied by means of an automatic watering system.
The rats were housed three per cage In polycarbonate cages equipped with disposable polyester woven filter tops. Autoclaved hardwood chips (Iso-Drl , Becton, Dickinson, and Carworth, Warrensburg, N.Y.) were used as bedding. The cages were changed, washed, and provided with fresh bedding twice per week. Filter tops were replaced once per month.
HONS 000267
Rats fed Aroclor 1254 were housed In the same room as rats
treated with aflatoxin
(CAS 1162-65-8), lead (li) acetate (CAS
301-04-2), hexachlorophene (CAS 70-30-4), or dieldrin (CAS
60-57-1) in the feed.
E. Subchronic Studies
Subchronic feeding studies were conducted with male and female Fischer 344 rats to estimate the maximum tolerated dose of Aroclor 1254, on the basis of which low, mid, and high concentrations (hereinafter referred to as "low doses", "mid doses", and "high doses") were determined for administration in the chronic studies. In the subchronic studies, Aroclor 1254 was added to feed in concentrations of 25, 50, 100, 200, or 400 ppm. Treated and control groups each consisted of 15 male and 15 female rats* The chemical was provided in feed to the treated groups for 8 weeks.
The animals receiving 400 ppm were inactive, had occasional diarrhea and tremors, and failed to gain weight. At this dose 4/15 males and 1/15 females died. Enlarged livers were observed on gross examination, and histologically atypical hyperplasia was observed. At 200 ppm, body weights for both males and females were approximately 70% of those of the controls, and mild hepato cellular pleomorphlsm was seen histologically In the livers.
6 HONS 000266
Rata treated with 25 ppm Aroclor 125A had enlarged livers, but no evidence of histologic abnormalities. Weight gain in all animals treated at doses lower than 200 ppm was comparable to that in controls, and there was no mortality below A00 ppm. The low, mid, and high doses for the chronic studies were set at 25, 50, and 100 ppm.
F. Design of Chronic Studies
'
The design of the chronic studies is shown in table 1.
G. Clinical and Pathologic Examinations
.
All animals were observed daily for signs of toxicity and palpated for masses at each weighing. Animals were weighed individually every other week for 12 weeks, and once every fourth week for the remainder of the study. Animals that were moribund at the time of clinical examination were killed and necropsled.
The pathologic evaluation consisted of gross examination of major
organs and tissues from killed animals and from animals found
dead.
The following tissues were routinely examined micro
scopically from both treated and control animals: lungs and
bronchi, spleen, liver, testes, pituitary, kidney, and brain. In
addition, sections of stomach, urinary bladder, thyroid, uterus,
and ovary were examined in a majority, of the controls; these
7 HONS 000269
Table 1. Design of Aroclor 1254 Chronic Feeding Studies In Rats
Sex and Treatment Croup
Males
Matched-Control
Low-Dose
Mid-Dose
High-Dose
Females
'
Matched-Control
Low-Dose
Mid-Dose
High-Dose
Initial Mo. of Anlmalsa
Aroclor 1254 in Diet**
(PPM)
Time on Studv
Treated0 Untreated
(weeks)
(weeks)
24 0
105
24 25 105
24 50 ' 105
24 100
105
24 0
105
24 25 104-105
24 50 104-105
24 100
105
All animals were 53+2 days of age when placed oiPstudy. 15All diets contained 3Z corn oil. cAll animals were started on study within 2 days of each other.
HONS 000270
tissues were taken from treated rata only if a 'lesion was found
at necropsy. Occasionally* additional tissues were examined
microscopically.
Cross lesions from all animals were also
examined microscopically. The different tissues were preserved
in 10% buffered formalin* embedded in paraffin* sectioned* and
stained with hematoxylin and eosin. Special staining techniques
were utilized when indicated for more definitive diagnosis.
A few of the tissues selected by design from some animals were not examined* particularly from those animals that died early. Thus* the number of animals from which particular organa or tissues were microscopically examined varies* and does not necessarily represent the number of animals that were placed on study in each group.
H. Data Recording and Statistical Analyses
Pertinent data on Chia experiment have been recorded in an auto~ matlc data processing system* the Carcinogenesis Bloassay Data System (Linhart et al., 1974). The data elements Include descrip tive Information on the chemicals, animals* experimental design, clinical observations* survival* body weight, and individual pathologic results* as* recommended by the International Union Against Cancer (Berenblum* 1969). Data tables were generated for verification of data transcription and for statistical review.
9 HONS 000271
These data were analysed using the statistical techniques described In this section. Those analyses of the' experimental results that bear on the possibility of carcinogenicity are discussed in the statistical narrative sections.
Probabilities of survival were estimated by the product-limit
procedure of Kaplan and Meier (1958) and are presented In this
report In the form of graphs.
Animals were statistically
censored as of the time that they died of other than natural
causes or were found to be missing; animals dying from natural
causes were not statistically censored. Statistical analyses for
a possible dose-related effect on survival used the method of Cox
(1972) for testing two groups for equality and Tarone's (1975)
extensions of Cox's methods for testing for a dose-related trend.
One-tailed P values have been reported for all tests except the
departure from linearity test, which is only reported when its
two-tailed P value is less than 0.05.
The Incidence of neoplastic or nonncoplastlc lesions has been given as the ratio of the number of animals bearing such lesions st a specific anatomic site (numerator) to the number of animals nccropsied (denominator).
The purpose of the statistical analyses of tumor incidence Is to determine whether animals receiving the test chemical developed a
10 MONS 000272
significantly higher proportion of tumors than, did the control animals. As a part of these analyses* the one-tailed Fisher exact test (Cox, 1970) was used to compare the tumor Incidence of a control group with that of a group of treated animals at each dose level. When results for a number of treated groups (k) are compared simultaneously with those for a control group, a correction to ensure an overall significance level of 0.05 may be made* The Bonferroni inequality (Miller, 1966) requires that the P value for any comparison be less than or equal to 0.05/k. In cases where this correction was used, it is discussed In the narrative section. It Is not, however, presented In the tables, where the Fisher exact P values are shown.
The Cochran-Armitage test for linear trend In proportions, with continuity correction (Armltage, 1971), was also used. Under the assumption of a linear trend, this test determines if the slope of the dose-response curve is different from zero at the one tailed 0.05 level of significance. Unless otherwise noted, the direction of the significant trend Is a positive dose relation ship. This method also provides a two-tailed test of departure from linear trend.
A time-adjusted analysis was applied when numerous early deaths resulted from causes chat were not associated with the formation of tumors. In this analysis, deaths that occurred before the
11 MONS 000273
first tumor was observed were excluded by basing the statistical
tests on animals that survived at least 52 weeks* unless a tumor
was found at the anatomic site of interest before week 52. When
such an early tumor was found, comparisons were based exclusively
on animals that survived at least as long as the animal In which
the first tumor was found. Once this reduced set of data was
obtained, the standard procedures for analyses of the Incidence
of tumors (Fisher exact tests, Cochran-Armltage tests, etc.) were
followed.
'
When appropriate, life-table methods were used to analyze the incidence of tumors. Curves of the proportions surviving without an observed tumor were computed as In Saffiottl et al. (1972). The week during which an animal died naturally or was sacrificed was entered as the time point of tumor observation. Cox's methods of comparing these curves were used for two groups; Tarone's extension to testing for* linear trend was used for three groups. The statistical tests for the Incidence of tumors which used life-table methods were one-tailed and, unless otherwise noted* in the direction of a-- positive dose-- relationship. Significant departures from linearity (P < 0.05, two-tailed test) were also noted.
The approximate 95 percent confidence interval for the relative risk of each treated group compared to its control was calculated
12 HONS 000274
from the exact interval on the odds ratio (Cart, 1971). The relative risk is defined sb pt/pc where pt Is tine true binomial probability of the Incidence of a specific type of tumor in a treated group of animals and pc is the true probability of the spontaneous incidence of the same type of tumor in a control group. The hypothesis of equality between the true proportion of a specific tumor in a treated group and the proportion in a control group corresponds to a relative risk of unity. Values in excess of unity represent the condition of a larger proportion in the treated group than in the control.
The lower and upper limits of the confidence Interval of the
relative risk have been included in the tables of statistical
analyses.
The Interpretation of the limits is that in
approximately 951 of a large number of identical experiments, the
true ratio of the risk in a treated group of animals to that in a
control group would be within the Interval calculated from the
experiment. When the lower limit of the confidence Interval is
greater than one, it can be Inferred that a statistically
significant result (P < 0*025 one-tailed test when the control
Incidence is not zero, P < 0.050 when the control incidence is
sero) has occurred. When the lower limit is less than unity, but
the upper limit is greater than unity, the lower limit indicates
the absence of a significant result while the upper limit
13 MONS 000275
Indicates that there is a theoretical possibility of the induction of tumors by the test chemical, which could not be detected under the conditions of this test.
14 HONS 000276
III. RESULTS
A. Body Weights and Clinical Signs
Beginning at about week. 10 for the hlgh-dose groups and about week 20 tor the mid-dose groups, mean body weights of both male and female rats fed Aroclor 1254 at the doses used in this bloassay were lower than those of the controls (figure 1). Hean body weights of low-dose males appeared comparable to those of controls throughout the study, while mean body weights of lowdose females were lower during the second year of the study. At week 30, an Intercurrent respiratory Infection In the colony caused weight loss, but no deaths; animals recovered within 30 days without treatment for the infection.
Clinical signs associated with administration of Aroclor 1254 Included alopecia, amber-colored urine, facial edema, exoph thalmos, and cyanosis. These signs were apparent among the hlgh-dose groups beginning at week 72 and among the mid-dose groups at week 104 of the study.
B. Survival
'
The Kaplan and Meier acurves estimating the probabilities of survival for male and female rats fed Aroclor 1254 in the diet
15 HONS 000277
MEAN BOOT WEIGHT (Ql
MEAN BODY WEIGHT (G)
Figural. Growth Curvet (or Ritr Fed Aroclor* 1254 in tho Diet 16 MONS 000228
Fi|wa 2. Survival Curves lor Rats Fad Aroclor" 1254 in the Diet 17 HONS 000279
at the doses used in this study, together with those of the
controls, are shown In figure 2.
'
For males, the result of the tarone test for positive doserelated trend in mortality over the period is significant (F < 0.001); 92% of the control, 83% of the low-dose, 58% of the mid-dose, and 46% of the high-dose rats survived to the end of the study. Among females, the Tarone test showed a probability level greater than 0.05. In females, 67% of the control, 79% of the low-dose, 83% of the mid-dose, and 71% of the high-dose rats survived to termination of the study. Sufficient numbers of rats of both sexes were available for meaningful statistical analyses of the incidences of late-developing tumors*
C. Pathology
Histopathologic findings on neoplasms in rats are summarized in Appendix A, tables A1 and A2; findings on nonneoplastic lesions are summarized in Appendix B, tables B1 and B2.
A variety of neoplastic processes were observed in both the control and treated rats, and, with the exception of the liver, the incidences of these neoplasms were comparable in the control and treated groups. Interstitial-cell tumors of the testes were present in the majority of control and treated males. The next most frequently observed neoplasm was leukemia of either the
- 18 MOWS 000200
granulocytic or lymphocytic type, and it involved multiple
organs. The Incidence of this neoplastic process was comparable
in the control and treated groups. The following neoplasms were
also present in some control and treated rats but without
compound association:
squaroous-cell carcinomas of the skin,
alveolar/bronchlolar adenomas of the lung, and uterine
endometrial stromal polyps.
No proliferative lesions of the hepatocytes were found in the control animals in the study. The incidence of these prolifera tive lesions among treated animals was as follows:
HALES
Low Dose
Mid Dose
High Dose
Number of Animals
Necropsied
(24)
(24)
(24)
Nodular Hyperplasia 5 8 " 12
Adenoma, NOS* 0 0 i
Hepatocellular
Carcinoma
0i 2
Total Incidence
5 9 15
*Not otherwise specified
FEMALES
Low Mid High
1Dose .
Dose
(24)
(22)
(24)
6--- 0
91
2
000
6 10 19
The areas of nodular hyperplasia appeared to be microscopically similar to what is currently termed "focal areas of cellular
19 HONS 000281
alteration*' (Squire and Levitt, 1975). Neither this legion nor
any hepatocellular adenomas or carcinomas were diagnosed In the
controls.
The hepatocellular carcinomas were characterized
microscopically by large foci of proliferating hepatocytes
Involving several lobules. These hepatocytes were bizarre in
appearance, sometimes containing two or more nuclei.
The
sinusoidal architecture was lost, and frequently mitotic figures
were present. These neoplasms compressed the surrounding normal
liver tissue, and the cell plates usually were three to five
cells in thickness. The hepatocellular adenomas were character
ized by large foci involving several lobules of swollen, severely
vacuolated hepatocytes still maintaining the general sinusoidal
architecture of the liver. In general, the foci of nodular
hyperplasia Involved two or more hepatic lobules and contained
hepatocytes whose tinctorial properties were distinctly different
from those of the surrounding liver tissue. Occasionally, these
foci would contain severely vacuolated hepatocytes, and in some
Instances, there were small foci of basophilic hepatocytes.
'
The results of the histopathologic examination indicate that the administration of Aroclor 1254 at the three doses used in this study had an effect with respect to proliferative lesions of the liver and gastrointestinal * tract. There were three hepatocellu lar carcinomas in male rats and a dose-related increase, in
20 HONS 000282
nodular hyperplasia In both the male and female animals. There was one carcinoma and four adenocarcinomas in 'the gastrolntestlnal tract of treated rats. These neoplastic lesions are seen only sporadically and at a low Incidence in the Fischer 344 rat; In this study no lesions of these types were diagnosed in cither the male or female controls.
D. Statistical Analyses of Results
*
Tables Cl and C2 In Appendix C contain the statistical analyses of the incidences of those primary tumors that occurred in at least two animals in one group and with an Incidence of at least 51 of one or more treated groups.
In male rats, the results of the Cochran-Armltage test for
positive dose-related trend In the Incidences of leukemia and of
combined leukemia and lymphona are significant (P - 0.022 and P
0.009, respectively). The corresponding results of the Fisher
exact test, however, are not significant in any treated group
when compared with the controls. There is no other incidence of
tumors at any specific site in either sex which Is statistically
significant.
A significant Cochran-Armltage trend In the
negative direction la observed in the incidence of Interstitial
cell tumor of the testis, where the Incidence In the controls
exceeds those in the mid- and hlgh-dose groups.
21 MGNS 000283
In each of the 95% confidence intervale of relative risk, shown In the tables, the value of one is included; this Indicates the absence of significant positive results. It should also be noted that each of the intervals has an upper Holt greater than one. Indicating the theoretical possibility of the induction of tumors by Aroclor 1254, which could not be detected under the conditions of this test.
22 HONS 000264
IV. DISCUSSION
At the doses used In this bioassay, Aroclor 1254 was toxic to
both male and female Fischer 344 rats, as shown by the
dose-related depression of mean body weights and the clinical
signs which occurred during the second year. Kean body weights
of mid- and high-dose males and of all treated females were
consistently lower than those of the corresponding controls after
the initial growth phase. An intercurrent respiratory infection
at week 30 resulted In temporary weight loss, but no deaths, in
all groups Including the controls; the animals later recovered
without treatment. Clinical signs Including alopecia, amber-
colored urine, facial edema, exophthalmos, and cyanosis occurred
in the hlgh-dose groups beginning at week 72 and in the mid-dose
groups at week 104. Survival among males, but not among females,
showed a significant dose-related trend. Adequate numbers of
animals of both sexes survived for meaningful statistical
analyses of the Incidences of tumors.
_____
The combined incidences of lymphoma and leukemia in males were significant (controls 3/24, low-dose 2/24, mid-dose 5/24, hlghdose 9/24, P - 0.009), using the Cochran-Araitage test for positive dose-related trend, but not in females (controls 4/24, low-dose 6/24, mid-dose 6/24, high-dose 6/24). Since the results of the Fisher exact test for Increased incidence were not
23 MONS 00028S
significant for any of these groups, the occurrence of these lesions cannot clearly be related to the administration of Aroclor 1254.
Hepatocellular changes including hyperplastic nodules, adenomas,
and carcinomas were found In treated animals, but none of these
lesions were found in control animals In this study* Hepato
cellular carcinomas were observed In one mid-dose and two hlgh-
dose males, and hepatocellular adenomas were observed In one
hlgh-dose male, one mid-dose female, and two high-dose females. Nodular hyperplasia was diagnosed with a dose-related frequency
in the low-, mid-, and hlgh-dose male and female rats. Although
the Incidences of the tumors were not significant, the occurrence
of these proliferative lesions appeared to be related to
treatment.
.
In the stomach, jejunum, or cecum, adenocarcinomas were observed
in two treated males and In two treated females as well as a
carcinoma In one treated male. None of these lesions was found
in control animals in this study, suggesting that the lesions --
although not statistically significant -- may be related to the
administration of Aroclor 1254*
The toxicity of polychlorinated biphenyls (PCBs) has been reviewed by several groups, including the Environmental
24 HONS 000286
Protection Agency (1976), National Research Council (1976), Panel
on Hazardous Trace Substances (1972), and International Agency
for Research on Cancer (1974).
Kimbrough et al. (1972)
demonstrated hepatic adenoflbrosls In male and female Sherman rats fed Aroclor 1254 at up to 500 ppm for 8 months. A similar PCB, Kanechlor 500, fed for 12 months to male Ulster rats.
Induced nodular hyperplasia at doses of 100-1,000 ppm; at 1,000 ppm, cholaoglofibroais also was induced (Ito et al., 1974). KepiInger et. al. (1971; see also EPA Crltera Document PCBs, 1976) fed Charles River rats up to 100 ppm Aroclor 1254 for 24 months
and reported originally that there was no significant Increase In hepatic tumors In this study; re-evaluation of the liver slides, however, Indicated a significant Incidence of nodular hyperplasia In treated rats, compared with controls. Ito et al. (1973) observed nodular hyperplasia and well-differentiated hepatocellular carcinoma In male strain dd mice fed 500 ppm Ksnechlor 500 for 8 months, and Kimbrough and Linder (1974)
observed adenoflbrosls and hepatomas in BALB/cJ mice fed 300 ppm
Aroclor 1254 for 11 months.
.
In a study of a closely related PCB, Kimbrough et al. (1975) observed hepatocellular carcinomas in female Sherman rats fed 100 ppm Aroclot 1260 for 21 monthB.
It is concluded that under the conditions of this bloassay, 25
HONS 000287
Aroclor 1254 was not carcinogenic in Fischer 34,4 rats; however, a high Incidence of hepatocellular proliferative lesions In both male and female rats was related to treatment. In addition, the carcinomas of the gastrointestinal tract may be associated with treatment in both males and females*
26 HONS 000288
V. BIBLIOGRAPHY
Armlcage, P., Statistical Methods In Medical Research. John Wiley ( Sons, Inc., New York, 1971, pp. 362-365.
Berenblum, 1., ed., Carcinogenicity Testing: A Report of the
Panel on Carcinogenicity of the Cancer Research Commission
of the UICC. Vol. 2. International Union Against Cancer,
Geneva, 1969.
"
Broadhurst, M. G., Use and replaceablllty of polychlorinated biphenyls. Environ. Health Perspect. 2:81-102. 1972.
Cox, D. R., Regression models and life tables, Jj_ R^ Statist. Soc. B36(2):187-220, 1972.
Cox, D. R., Analysis of Binary Data. Methuen & Co., Ltd., London, 1970, pp. 68-52.
Environmental Protection Agency, Polychlorinated Biphenyls
(PCBs).
Toxic Substances Control.
Federal Register
62(100), 26566-26577, 1977.
Environmental Protection Agency, Criteria Document PCBs, U. S. Government Printing Office, Washington, D. C., 660/9-76-021.
Flnklea, J.,
Hlnners, residues problem.
Prlester, L. E., Creason, J. P., Hauser, T.,
T., and Hammer, D. I., Polychlorinated biphenyl In human plasma expose a major urban pollution AJPH 62(5):665-651. 1972.
Cart, J. J., The comparison of proportions:
a review of
significance tests, confidence limits and adjustments for
stratification. Rev. Int. Stat. Inst. 39(21:168-169. 1971.
Hubbard, H. L., Chlorinated biphenyl and related compounds. Klrk-Othmer Encyclopedia of Chemical Technology. Vol. J>, Interscience Publishers, New York, 1966, pp. 289-297.
International Agency for Research on Cancer, Some anti-thyroid
and related substances, nltrofurans and Industrial
chemicals.
1ARC Monographs on the Evaluation of the
Carcinogenic Risk of Chemicals to Man: Vol. _7 World Health
Organisation, Geneva, 19767-pp. 261-289. ---
--
27 HONS 000289
Ito, N., Nagasaki, H., Makiura, S., and Aral, M.,
Hlstopathologlcal studies on liver tumorlgenesis in rata
treated with polychlorinated biphenyls.
Cann 65
(6):545-549, 1974.
Ito, N., Nagasaki, H., Aral, M. Makiura, S., Sugihara, S., and Hlrao, K., Histopathologic studies on liver tumorlgenesis Induced In nice by technical polychlorinated biphenyls and its promoting effect on liver tumors induced by benzene hexachlorlde. J. Natl. Cancer Inst. 51(5): 1637-1642, 1973.
Kaplan, E. L, and Meier, P., Nonparametric estimation from
incomplete observations.
^ Aroer. Statist. Assoc.
53:457-481, 1958.
Keplinger, M. L., Fancher, 0. E., and Calandra, J. C., Toxicologic studies with polychlorinated biphenyls. Toxicol. AppI. Pharmacol. 19(2):402-403. 1971.
Kimbrough, R. D., Squire, R. A., Linder, R. E., Strandberg, J.
D,, Montall, R. J., and Burse, V. W., Induction of liver
tumors in Sherman strain female rats by polychlorinated
biphenyl Aroclor 1260.
National Cane. Inst. 55(6):
1453-1456, 1975.
Kimbrough, R. 0. and Linder, R. E., Induction of adenofibrosis and hepatomas of the liver in BALB/cJ mice by polychlorinated biphenyls (Aroclor 1254). ^ Natl. Cancer Inst. 53(2):547-552, 1974,
Kimbrough, R. D., Linder, R. E., and Gaines, T. B., Morphological changes in livers of rats .fed polychlorinated biphenyls. Arch. Environ. Health 25:354-364, 1972.
Llnhart, M. S., Cooper, J. A., Martin, R. L., Page, N. P., and Peters, J. A., Carcinogenesis bioassay data system. Comp, and Blomed. Res. 7:230-248. 1974.
Miller, R. G., Jt., Simultaneous Statistical Inference. McGrawHill Book Co., New York, 1966, pp. 6-10.
National Research Council, Report of Organic Contaminants (unpublished). National Research Council, Assembly of Life Sciences, Washington, D.C., 1976.
28 MONS 000290
Panel on Hasardoua Trace Substances,
Polychlorinated
biophenyls-environmental impact. Environ, Res, .5:249-362,
1972,
*
Poffenberger, N. and Hubbard, H. L,, Diphenyl and terphenyls. Klrk-Othwer Encyclopedia of Chemical Technology, Vol, J., Interscience Publishers, New York, 1965, p. 193.
Safflottl, U., Montesano, R., Sellakumar, A. R., Cefis, F, and Kaufman, D. G., Respiratory tract carcinogenesis In hamsters induced by different numbers of administrations of benzo(a) pyrene and ferric oxide. Cancer Res 32:1073-1081. 1972.
Squire, R. A. and Levitt, M. H., Report on a workshop on classification of specific heptocellular lesions In rats. Cancer Res. 35:3214-3223. 1975,
Tarone, R, E., Tests for trend in life table analysis. Blometrika 62(3):679-682, 1975.
29 HONS 000291
APPENDIX A
SUMMARY OF THE INCIDENCE OF NEOPLASMS IN RATS FED AROCLOR 1254 IN THE DIET
31 MONS 000292
TABLE A1.
'
SUMMARY OF THE INCIDENCE OF NEOPLASMS IN MALE RATS FED AROCLOR 12S4 IN THE DIET
CONTROL
AN1HAIS IIITIAU! IN STUDI
INIRA1S IBCBOPSIID AN1BAIS 1KAHINID SISTOPATItOLOCICAltT
24 24
LOW DOSE
24 24 24
INTIOUNERTAM SISTER
SKIN SQDAROOS CtLt PAPlllOHA S00AR0U9 CIU CARCINORA
SUBCUT TISSOI SPUMOUS cut CARCINORA P1NR0HA RIXORA
RESPXAATORT SIS1IR
ILORG/BRONCHUS PArUtOHA, NOS
10R6 CARCINORA, 105, RETASTRTIC ALIBOIAR/BRCNCHIOLAR ADERONA RARARTCHA
124) 1 (41)
(2) 1 (4E)
(23)
(23) 1 (A*)
(24)
(24) 1 (MS) 1 (Mt)
(24) I (44)
(24)
1 (4)
RERATOPOIETIC SISTER
ROlTlPtB ORGANS IMPHOCTTIC UUKERIA 0BARU10CI11C lEUXEHIA
LIRPH RODE BA110NANT tlHPMORA, NOS
(24) 3 (US)
(3|
(24) 2 (*)
(3)
CIRCULATOR! SISTER
1011
............................................ ................
HUME* or AklRALS WITH TISSOE EIAHINED RlCftOSCOFICALlY IURBBR Or AN]IMIS NECROPSIID
MID DOSE
24 24 24
HIGH DOSE
24 24 24
(24)
(24) 1 (<*)
(2*)
1 (41)
(24) 1 (44)
123)
(23) 2 (91)
(24)
(24) 2 (M|
(24) S I2TI)
(4 |
(2U> nm 4 (12*>
(9) 1 4 20m
33 HONS 000293
TABLE A1. MALE RATS: NEOPLASMS (CONTINUED)
CONTROL
LOW DOSE
MID DOSE
HtQHDOU
tXOISIIfl STS1Id mUURT OURD
sniicon*, nos turn
I*MpbPhiToOh*C,ZlnIOcsUR CRICIR08* ISTO*0IMBCHoc*rc2Ncn*, nos JBJcUK*Gcnino*.*os cecAuDnNOC*FC J NCfl ft , NOS
ORlRfttV SVSTtfl HORS
IIDOCim JTStJH riTUlT*RV ( ftOfROR*, RCS UDRAHttiOmCMRONCCITCH*
RCPRobumvE sisTcn mim
immiTifti-cni. tuhor CROTON
rmon*
H) <2*1 (2| can
---
(23) (D1 (ICOf)
(2*1 2 <B*>
(1)
(22*) (2*1) (4)
(224*) (IftOt) (24>
VIMOUS 313TIB
Hlfl I ROBRFR OF ftNUULS KITH TISSUE BUHim RXCRQSCOFICULT R08BER OF minus RBCftOtSirD
O)1 (331) <2*1
1 l*t) (2)1 <^0I)
---id' ) (1001)
(22)
(24) 20 (831) (2V)
(2*) 21 ((4888)|
(6) n>1 (1008) (4)
(2*)
124) 20 (83X) (24)
34 HONS 000294
TABLE A1. MALE BATS: NEOPLASMS (CONTINUED)
CONTROL
LOW DOSE
SPECIAL SENSE CNGAN3 NOVI
NO SCil LOSS EL IT A t SYSTEM IONS
PCDT CAVITIES
TUNICA VAGINALIS HESOTHEL1CHA, NALIONANT
(2fl) 1 (OK)
(2)
ALL OTHER SYSTEMS RONE
ANXRAL DISPOSITION SDHRANI
ANINALS INITIALLY IN STODY NAT0RAL DIAlHi RON1RUHD SACNiriCE SCHEDULED SACNIPICE ACCIDENTALLY KILLED TERMINAL SACSIPIC1 ANINAL HISSING
|_JKUiOSS.MlUZM.limi.2.
24 2
22
2*
20
NUNBEN OE ANINALS WITH TISSUE EIANINED MICROSCOPICALLY RUNNER Of ANIMALS RECN0PS1BD
'MID DOSE <2)
1U
HIGH DOSE
(2)
2 12 11
35 MONS 000295
TABLE A1, MALE BATS: NEOPLASMS (CONTINUED)
CONTROL
LOW DOSE
MID DOSE
TUMOR SUMMARY
total minus kith mum to no ns* TOTAL RRJKART TUMORS
TOTAL MUimS WITH BENIGN TUHORS
TOTAL 8XNJCK TUMORS
..
u 32
2 27
2 32
2* 30
20 32
20 23
TOTAL AR1RUS WITH HA LI6NANT TUMORS TOTAL MALIGNANT TUMORS
S 5
2
9 9
TOTAL ANIMAL! WITH SECOMUARI TUMORS* TOTAL STCCRCAFI TUMORS
1 l
TOTAL AHIHA1S WITH TUMORS UNCERTAIN-
UMJCN OR HALIOHANT TOTAL UNCIRTAIN TUMORS
TOTAL AN1MAI! WITH TUMORS UNCERTAINTRISARI OR M1TASTATIC
TOTAL UNCIRTAIN TUMOA5
PRliAM TUMORS! ALL TUMORS EICEPT SECORPARI TUMORS < 5SCOMUARI TUMORS: METASTATIC TUMORS OR TUMORS INVASIVE INTO AM ADJACIH ORGAM
MfOHDOtt
21 37
20 23 12 >*
I
36 I
HONS 000296
TABLE A2.
SUMMARY OF THE INCIDENCE OF NEOPLASMS IN FEMALE RATS FED AROCLOR*' 1254 IN THE DIET
CONTROL
AR1BALS INITIALLY IN STUDY ANIMALS NECKOFSIED ANIMALS EIAM1N1D HISTOPATMOLOOICAllY
2* 24
LOW DOSE 24 24 24
INTIOUMERTAAt 1TS1EN
sum SQUAMOUS CILL CARCINOMA
IOBCOT TISSOI riftDOHA fieeosarccaa FIBROUS HISTIOCYTQA MAUGKART LIPOSARCCHA
(24) (24)
(24)
(24) 1 (*)
1 <*>
RESPIRATORY system
LORO
-
ALTEOLAR/BPONC MOLAR ADINOMA
(22) 1 (5*1
(2)
ICMATOPOXETIC SYSTEM
MULTIPLE OROANS NALlO.UnPIICIIA, LYMPHOCYTIC TIPS LYRPH0CY1IC LEUKEMIA GRANULOC 111C LEUKEMIA
SPLEEN GRANULOCYTIC LEUKEMIA
LYMPH RODE MAllQ.LYMPHOMA, HISTIOCYTIC TYPE
(2U) 1 (**) 3 (13*)
(19)
()
(24) 2 (SI) 4 <m)
(24)
(1)
CIRCULATORY SYSTEM
IBM. _ ______ -
.
RRREER or k HI HALS EJTS TISSOt CZHHIHSO HICROSCOrZCSLLT SOMBER Or RHIMHIS MECRORStED
MIOOOSE 24 24 24
MOM DOSE
24 24 24
124) 1 (*>
(24)
(24)
(24) 1 (!> 1 (41)
(24| 1 (41)
(24) (41)
. 4 (1?*) (24)
1 (41) (3)
(24)
(24) 1 (41) (I'D
(221 IH
1 (1I0*|
37 HONS 000297
TABLE A2. FEMALE RATS: NEOPLASMS (CONTINUED)
CONTROL
LOW DOSE
MID DOSE
HIGH 00*6
tiotsnvs SISTIN
LXVCR vabirrcMvirsteD cmchmi urns mioni, *cs
I8T0RACH mon, ics mWQCMtCIVCRA, DOS
(2J) (21)
(2*) 1 <*)
<3| 1 133%)
(22) 1 (S*>
n> 1 (100*)
limit ststir
eeeiTovsiim tract L1PCHA
mom oioirmtNiimo carcircra
fRPOCM VC StStlR
riTumitv ADENORA, VOS
(2*) (231
<231 <1TS|
|2) 1 <**)
<2*0 . 1 (S)
(22) (5*)
<2*1 (2*1
(22) 1 (5)
IIMOOOCTJVI IISTIB
RARRART OLilt ALBVORA, MCS apbrocarcircra, vos
IDTBIDS A1*N0CARC)*0RA, ROS lbOCA IN AC 1R0RATO05 P0L1F U10HT0RA EttDORBTMAL STHORAl POL TP
oviv ORANUIOSA'CILL TVRO*
'
(2*1 1 {(*)
(U)
2 0*1) (20)
(2*)
. .* n>
(12) 1 (OS)
(2)
____
(15)
1 <*) 5 (*2t)
13)*)
(U 1 <100*1
13)
V8MOWS SYS2IR
_I0M
iomc* or aiinau with tissue eufintto mcvoscorxcjan * vuiivei or saiffvis vrcvorsiru
<2*1 2 |M>
<61 i imi
<3*1 <33
(23) t <*)
<2)
fit 1 imi 1 (12*) 3 (50*)
3B HONS 000290
TABLE A2. FEMALE BATS: NEOPLASMS (CONTINUED)
CONTROL
LOW DOSE
SMClfcL SIHSZ OMIM
STB SSIICtOUS 1 DEVOCB RCI MON I
1**4)
C2)
B09CULO9KBLBTM SI STEM
Oil
B00I CATITIIS VO Iff
ILL 0X411 STS1IB9
1041
IRIML DXSE0911I0V SOKfllll
IVJBkLS 1H11IULY IN STODT V1TUML DEATH# noniBvnt sicejmce
SCHBDOLIO SICliriCB ICCIDHTAUr RULED
TBintNU SACRIFICE
tRlBlL NI3BIM0
24 1 7
1#
19
j T1C1UDI8 1DT01IZED IRIBAI3_______________________________________
$ iobmi or sums itb txssob biihxvbd bicioscoucult ROBBER or klllllis RECR0P9IED
MID DOSE
' (24)
1 (4)
HIGH DOSE (24)
2# 24
1 37 2C 17
39 MONS 000299
TABLE A2. FEMALE RATS: NEOPLASMS (CONTINUED)
CONTROL
LOW DOSE
MID DOSE
TOIOR SUlfHART
TOTAL ARIMAIS KITH RRIRART TORORS* TOTAL RRIRART TUMORS
11 12
18 2<
13
IT
TOTAL ANIMALS NITM OtVICN TO ROMS TOTAL SENIOR TUMORS
TOTAL ANIMALS NITR MALIGNANT TUMORS TOTAL HALIORANT TUMORS
T 8
8 0
13 U
8
8
9
TOTAL ANIRAIS NITH SECONDART TUMORS* TOTAL SECCRBART TONORS
1' 1
TOTAL ANIHAIS KITH TUMORS UNCERTAINSENIOR OR MALIGNANT
TOTAL UNCERTAIN TUMORS
1 1
TOTAL ARIMALS NITK TUMORS URCERTAINSRtMART OR HETASTATIC
TOTAL VNCIRTAXH TUMORS
RRIRART TUMORS! ALL TUMORS EICERT SECONDART TUMORS I SECONDART TUMORS! METASTATIC TUMORS OR TUMORS INVASIVE INTO AN RDJACIVT OROAN
HIGH DOS!
W
IT
T
9
10
40 HONS 000300
APPENDIX B
SUMMARY OF THE INCIDENCE OF NONNEOPLASTIC LESIONS IN RATS FED AROCLOR1254 IN THE DIET
41 MONS 000301
TABLE B1.
SUMMARY OF THE INCIDENCE OF NONNEOFLASTIC LESIONS IN MALE RATS FED AROCLOR* 1254 IN THE DIET
CONTROL
HURLS lilTIRLlT IN STUD!
INItULS NSCROPS1IC ANIMALS EXAR1NED MSTOPATROLOGICALIT
21 29 28
LOW DOSE
29 29 29
XNTB09BERTAR1 8IS1SM
SOBCOT TXSS01 CIST, VOS
.
(24) 1 (A*)
(297
XSF2BAT0RI STSTIM
TRACHEA INFLAMMATION, NOS
LONG/BRONCHUS BRONCHI ACTASIS 1NPLARRAT1C N, NOS
LONS BHPHTSBHA, NOS ATELECTASIS CONGESTION, NOS XNPLAHHA TIC N, NOS ABSCBSS, NOS
(39) 1 (5*)
(23) 1 <"*)
(23) 1 <*)
9 (39X)
2 <>
(29| 9 (IT*) y (*)
(29)
1 (81) 12 (50X)
2 (8S)
HIHATOPOIXTIC STSTBB
imiti
congestion, nos PIBROS!3 HBNATOPOlISIS
(23)
I (H*l
<28|
2 (**/
1 ("*>
IL1IDH NODE CONGESTION* NOS NECROSIS, NOS
MYFIRPLASIA, VOS
___ USIIDEIISSIS___
O) .2.J621L
(3)
RUBBER OP ANIMALS WITH TISSUE EXAMINED MICROSCOPICAL!T SOMBER Of RN1HA1S VBCROP51BD
MID DOSE 29 29 29
(2l
HIGH DOSE 29 29 29
(29)
(1)
(23) 7 (301)
(23) 2 (9*) 7 (30*) 3 (13*|
(23)
1 (41) 2 (*) (9)
1 (25*) 1 (25*)
(29) 1 (9)
(29) 1 (9S) 9 (17*) 1 (9ft) 2 ()
(24)
(5) > (20*)
43 MQNS 000302
TABLE B1. MALE RATS: NONNEOPLASTIC LESIONS (CONTINUED)
CONTROL
LOW DOSE
CILIAC ITHM "OC? LIflPtlANGIICtASIS
n> (3)
cxicuuroir sisirn RORt
tlCESTIVe SISTIfl
immiir claro munniTici, ros
U;R CONOtSTIOR. ROS IRPUMMATIC*, QRAROLOHATOUS CRARULOBA, ROS RCCROSIS# ROS NECROSIS* IOCAL NECROSIS' CIRIRAL NVPRRRLASIR. RODULAR ARC]ECTA SIS
STOMACH WrwriCWLOR til PEAFIA SI A LTBPHOID
OASTRIC NUCOSA CORCESTION, ROS HTPIRPLASIA, ROS
COLOR P1PR0SIS PIOBEMTATICM, ROS
CECUM &CROSIS' ROS
12*) 10 (*2)
(1T*> (21)
1 (5*1 (21)
di 1 (1001)
(2*) 10 (75*)
1 <**>
5 (21*)
UllNARY STS1IP
R10MET ..CZ2I4.I9L................................ -
(2*) -
(2*|
I NUMBER Or'MlMlLS R1TH T1SSQB EXkNXNID NZCROSCOFXCKL1T NONfltR Or MINUS NECNOrsIED
MID DOSE ()
(3) (2)
10 (2*|
1 (*D 0 |l) 2 (*) (2) (2) 1 (50*) (1) (1)
(2*)
HIGH DOSE
<s> 1 (20*)
(2*) (17*) 1 (*) 1 (*> 1 (**) 2 (> 1 (*)
12 (S0)
(6) 1 (H*>
W 1 (11*) 2 (33*)
() 1 (25*1 (25*)
(*> 1 (25*)
(2)
44 HONS 000303
TABLE Bt. MALE nATS: NONNEOPLASTIC LESIONS (CONTINUED)
rmonKmiTis, nos SC1SR0SIS
CONTROL
LOWbOSE 1 () 1 ()
IRDOCIIDK SIS1IB
PITOITHM CIST, IDS congestion, nos
NITERPLASIA, NOS
(231 1 (*>
(3) 1 (33*>
(20) 1 (>
itriooucTiu sister RONS
NERVOUS 5T3TIH
CONGESTION, NOS EDEflt, NOS ABSCESS, NOS INfARCT, NCS
(23)
(2* 1 ()
IMCIU SINSK ORGANS IONS
BOSCUAOSKBLETAl STSTEfl BONE
BOOT CAVITIES
INGUINAL REGION NECROSIS, 1ST
(2*) (25*)
<2) 3 (21*)
ALL OTNIR STSIlHS
-.1011 .....................................
.
PHASER OP ftPIHALS PITH TISSOP EXAHIPED HICPOSCOPlCALll PEEPER OP IPIPftLE PECPOP91EO
MIO DOSS
HIGH POSE
(22) ' (5*)
(1)
(2) 2 (*)
(2t) 1 (*> 1 (**>
1 ()
(2) 1 (>
(2) - (13*)
(2D * (17*)
45 HONS 000304
TABLE B1. MALE RATS: NONNEOPLASTIC LESIONS (CONTINUED)
CONTROL
LOW DOSE
mem houphoiogt sunn aft
HONE
IVNSrit or ANIMALS KITH TISSUE FUAINBD MCROSCOFICALLT NUNUt* or AN)MAIS NBCROFSIED
MID DOSE
HIGH DOSE
46 MONS 000305
TABLE B2.
SUMMARY OF THE INCIDENCE OF NONNEOPLASTIC LESIONS IN FEMALE
RATS FED AROCLOR 1254 IN THE OIET -
CONTROL
MIMIS XNZTIAILT IN STODI ARMAIS NSCROFSIIt ARMAIS tlARINID RISTOPATNOIOCICAUI
It
24 20
LOW DOSE
24 It It
XRtBQUflSNTABT SISTER RONE
INSPIRATOR? ST JTEN
LONC/SNORCHUS BN0NCK1BC1ASI3 ABSCESS# CCS
IS 10 ATELECTASIS C0N8ESTICN, NOS EITBCSIA XSrUSNATICN# NOS INELANNATICN# INTERSTITIAL ABSCISS# NOS
(72)
(22) 0**1 2 (9*) 1 (5*)
(2)
(24) s cm>
10 (42*)
i () i (*) i (*)
inATorozsnc sTSirn
SPLEEN conoesticn# nos RSMAT0F01ISXS
ITNPH RODE ITRPNANOIICTA3ZS IPFLAftRATICN, NOS
09)
() 2 (30S) 1 (25S)
(24) J (13*)
(1)
CXRCOLATONT SISTER
MYOCARDIUM .juuimii4.ics .
_.
(D \ l100ft
I onr or bbihuls mo tissoi bibhibed mcroscopicu.LT
OUHBBR or BH1HRLS BBCROPSirD
.
MID DOSE
24 24 30
HIGH DOSE
24 24 24
(24) 1 (41) 1 (41)
(24) 3 (13S) 6 (3 JR)
1 (*)
(24) 3 <U*I
(3)
(24) 1 (4t)
(24) 1 (**)
10 (42S) 1 ("*) 1 (*) 1 I**)
(22)
(1)
47 HONS 000306
TABLE B2. FEMALE RATS: NONNEOPLASTIC LESIONS (CONTINUED)
CONTROL
LOW DOSE
MID DOSE
D26SSTIVB S1STIN
limit
CONGESTION, NOS UPUHNATICR, NOS HfUftrtHTICN, CJtAKUCMTOOS ORANULOHA, NOS riBNOSIS NECROSIS, IOCAL HYPERPLASIA, NODULAR ANGIECTASIS NLNATOFOI ISIS
1IYR/PERIICRTAI XNPLAHRATICN, NOS
mt oocr lNPLAKNATICN, NOS
STOHACH BITIRTICULUN THDBNNA1 INC1DSI0N CYST CONGBSTXCK, NOS
IJBJUNUN 1NFLARNAIICN, NOS
COION XNFLANNATION, NOS
CBCUN 1NFLAHHATICN, NOS
123) 6 (26*1
3 (13*} (23) (2) (21)
0) 1 (ICO*)
n> O)
1 (1001)
(2) 6 (25*) 2m
i (*)
i (**) < (75*) 2 (SI)
1 (*)
(2) 2 (6*)
|2>
01
1 (33*)
(1) 1 (1Q0X)
(1)
(2 2) (10*) 1 (5*) 3 0") 1 (5*)
1 (5) (!*) 1 (5*)
(2 2)
(7*) (11*)
(1)
URINARY St SI IN
OBR1TOURINARY TRACT NECROSIS* fAT
IRtPNEV nyoronyhircsis CYST* NOS
(2)
1 (**)
(21)
1 ("*1
(2) 1 (*>
|2N) 1 (NX)
INOOCkINS STSYftt
PITUITARY ___ .U.1B3 ___ -
-
(23) 122) - -J.XUU___ - __ l.iSX)______
lusue* or Minus sits nssos ntsiuo nicsoscoricuu
* souses or missis Htcsorsxro
(20) 1 It*)
(2N)
(22)
MIOH OOSE
(2) 1 (NX)
17 (711)
1 ()
(2) (2N) (6)
2 (3JS) 1 (17*) 1 (171) (1) (1) (1)
(2*) (23)
1 (l)
123)
46 HONS 000307
TABLE B2. FEMALE RATS: NONNEOPLASTIC LESIONS (CONTINUED)
COBQKSTICK, OS SHOMtHJkQJC CTST
IPUBAL C0BQ8ST10B* >0S
CONTROL
IMt) 1 <*)
(3) 1 I501|
LOW DOSE 3 (IBS)
reproductive sistih
IMIAMIT QLlBt RVPEMPLASIR, CIST1C
*Tkm limCT, BOS
tOTtBUS MOROHITRA
PIOBETRA
PTINOS/SRPORIIRIUB
XBPLftHRATXCR, BOS NIPtRPMSM, NOS NIPtftPLIkSIft, C1ST1C
IQTEIUS/HTORITNXOB XBFURRMXCB, POCU
loviti/ovipoct CIST, BOS mruHnftTXCB, bos
OUSI CIST, IOS
POUICUMR CIST, FAROVftRXAR CIST
COBOKSTIOB. BOS
IBSCBSS, NOS
BOS
(26)
(26)
o) 6 (Ot)
(IB)
1 <7*1 ON)
OB) 2 OBI) 1 (7S)
(20) 1 (5*) 1 (5*) 1 (51) 1 (51)
(2N) 1 (S)
(2B)
02) 1 (St) 1 (81)
02) 1 40*)
(12)
02)
0)
IllfOUS SISTFH
BBftJB CONOBSTIOB. BOS
(2D 1 <!*)
(23)
BPtCIAL BBN9B CROftNS
III
.
(2B)
(2B)
UUIIUR
_
1 ibii
, i (Ml__
A
iomi or mms bitk txssob iuiiikd icioscopicm.lt
URIM or II1IUS IKIOmtD
MID DOSE 1 (5*)
(B)
(26) <2B)
1 (61) 05)
1 *<7*| t (71) 05) 1 (71) B (271) (15) 05)
(3) 2 (67*) 1 (331)
(2B>
(26)
HIOH DOSE 1 (t)
(26) (2*| (6) (6) (6)
1 (171) (6)
(22)
(2B)
49 MONS 000308
TABLE B2. FEMALE RATS: NONNEOPLASTIC LESIONS (CONTINUED)
CONTROL
LOW DOSE
ROfCUlOSKtltm SISTER MOMS
IODI CkfITXIS
lMOUim MICIOM UPOCMMtHCBl
(2R) '
(2M) 1 t*>
ill OTMBM SISTERS SORB
SriCUL ROSSNClOGt SUBSIST
VO LE8X0V HPOITED
iurih or mnus WITH tissue hammed bicioscopicm.it vunsta or irirus meciopsied
MIO DOSE <2>
HIGH DOSE 12*> 1
t 50 1 l MONS 000309
APPENDIX C
ANALYSES OF THE INCIDENCE OF PRIMARY TUMORS IN RATS FEU AROCLOR1234 IN THE DIET
51 HONS 000310
Table Cl. Analyses of the Incidence of Primary Tumors In Male Rats Fed Aroclor 1254 in the Diet
Topography: Morphology
Matched Control
Lung: Alveolar/Bronchlolar Adenoma^
0/24 (0)
P Valuesc*d
N.S.
Relative Risk (Matched Control)* Lower Limit Upper Limit
Weeks to first Observed Tumor
Rematopoeitic System:
Leukemia^
.
3/24 (13)
P Values'.d
P - 0.022
Relative Risk (Matched Control)* Lover Limit Upper Limit
Weeks to First Observed Tumor
98
Low Dose
0/24 (0) N.S.
2/24 (8) N.S.
0.667 0.060 5.292
78
Mid High Dose
2/24 (8)
N.S.
InfInite 0.305 Infinite
105
2/24 (8)
N.S.
Infinite 0.305 Infinite
90
5/24 (21)
N.S.
1.667 0.369 9.600
84
8/24 (33)
N.S.
2.667 0.739 13.700 .u
HONS 000311
Table Cl. Analyses of the Incidence of Priaary Tumors In Hale Rats Fed Aroclor 1254 In the Diet*
(continued) Tooo&raohv: Morphology
Matched Control
Low Dose
Kid Dose
High Dose
Hematopoietic System: Lymphoma or Leukemia**
3/24 (13)
2/24 (8)
5/24 (21)
9/24 (38)
P Valuesc>d
P - 0.009
N.S.
N.S.
N.S.
Relative Risk (Matched Control)f Lower Limit
, Upper Limit
0.667 0.060 5.292
1.667 0.369 9.600
3.000 0.871 15.010
Weeks to First Observed Tumor
98
78
84 73
Pituitary: Adenoma, N0Sb
0/24 (0)
2/24 (Si)
0/24 (0)
0/24 (0)
P Values'>d
Relative Risk (Matched Control)^ Lower Limit Upper Limit
Weeks to First Observed Tumor
N.S. --
N.S.
InfInite 0.305 Infinite
105 I
N.S.
- -- --
__
' N.S.
, -- --
. __
HONS 000312
Table Cl. Analyses of Che Incidence of Primary Tumors in Hale Rats Fed Aroclor 1254 in the Diet*
(continued!
ToDoeraohv: Moroholoav
Liver: Hepatocellular Carcinoma**
Hatched Control
0/24 (0)
Low Pose
0/24 (0)
Hid Dose
1/24 (4)
High Dose
2/24 (8)
P Values*
N.S.
N.S.
N.S.
N.S.
Relative Risk (Hatched Coacrol)^ Lover Limit Upper Limit
Weeks to First Observed Tumor
_
Infinite
Infinite
0.055
0.305
__
Infinite
Infinite
105 103
Testis: laterstitial-cell
Tumor**
.
F Values**^
24/24 (100) P - 0.013 (N)
24/24 (100) N.S.
20/24 (83) N.S.
20/24 (83) N.S.
Relative Risk (Hatched Control)f Lover Limit Upper Limit
Weeks to First Observed Tumor
'1
98
Treated groups received doses of 25, 50, or 100 ppm.
78
00..080303
1.200
77
0.833
0.000
1.200
______v
^Number of tumor-bearing animals/number of animals necropsled (percent).
HONS 000313
Table Cl. Analyses of the Incidence of Prismry Tumors in Hale Rats Fed Aroclor 1254 in the Diet*
(continued)
______ -
cBeneath the Incidence of tumors in the control group is the probability level for the Cochran-
Annitage test when P < 0.05; otherwise, not significant (N.S.) Is indicated* Beneath the inci
dence of tumors in a treated group is the probability level for the Fisher exact test for the
comparison of that treated group with the matched-control group when P < 0*05; otherwise,
not significant (N.S.) is indicated*
<*A negative trend (N) Indicates a lower Incidence in a treated group than in the control group.
eThe probability level for departure from linear trend is given when P < 0.05 for any comparison*
fThe 95% confidence Interval of the relative risk between each treated group and the matchedcontrol group.
wn O'
HONS 000314
f
Table C2. Analyses of Che Incidence of Primary Tumor* In Female Rats Fed Aroclor 1254 In the Diet*
Topoaraohv: Moroholoav
Matched Control
Hematopoietic System: Leukemia^
4/24 (17)
P Valuesc^
N.S.
Relative Risk (Matched Control)^ Lower Limit Upper Limit
Weeks to First Observed Timor
81
Hematopoietic System: Lymphoma or Leukemia^
' 4/24 (17)
P Values0*d
N.S.
Relative Risk (Matched Control)f Lover Limit Upper Limit
Weeks to First Observed Tumor
81
Low Pose
6/24 (25) M.S.
1.500 0.411 6.316
74
6/24 (25)
N.S.
1.500 0.411 6.316
74
Mid Pose
6/24 (25) N.S.
1.500 0.411 6.316
99
6/24 (25)
N.S.
1.500 0.411 6.316
99
High Dose
4/24 (17)
N.S.
1.000
0.211 4.754
84
6/24 (25)
N.S.
1.500 0.411 6.316
i 84
HONS 000315
Table C2. Analyses of tha Incidence of Primary Toaors la Penal* lata Fed Aroclor 1254 In the Diet*
ToDosraohv: Morpholoar
Matched Control
Pituitary: Adenoma, N0Sb
4/24 (17)
P Values0*'*
N.S.
Relative Risk (Matched Control)* Lower Limit Upper Limit
Uoolta to First Observed Tunor
100
Liver: Adenoma, N0Sb
0/24 (0)
P Values0*1*
M.S.
Relative Risk (Hatched Control)* Lover Limit Upper Limit
Weeks to First Observed Tumor
--
Low Dose
1/24 (4)
M.S.
0.250 0.005 2.288
105
| 0/24 (0)
N.Ss ,--
-- --
i~
Mid Dose
1/24 (4)
M.S.
0.250 0.005 2.288
105
1/24 (4)
M.S.
Infinite 0.055 Infinite
105
High Dose
1/24 (4)
M.S.
0.250 0.005 2.288
103
2/24 (8)
N.S.
Infinite 0.305 Infinite
105
MOMS 000316
Table C2. Analyses of the Incidence of Primary Tumors in Fenale Rats Fed Aroclor 1254 In the Diet*
(continued)
Tooo&raohv: Koroholocv.
Mammary Gland: Adenocarcinoma, NOS*3
P Values0*'*
Matched Control
0/24 (0) N.S.
Low Dose
4/24 (17) N.S.
Mid Dose
0/24 (0) N.S.
High Dose
0/24 (0) N.S.
Departure from Linear Trend6
P - 0.003
Relative Risk (Hatched Control)* , Lower Limit
Infinite 0.961
._
_
_
Upper Limit
Infinite -- --
_Weeks to First Observed Tumor
_
105
Mammary Gland: Adenoma or Adenocarcinoma, NOS*3
P Values011*
1/24 (4) N.S.
4/24 (17) N.S.
0/24 (0) N.S.
0/24 (0) N.S. .
Departure Eton Linear Tren<l
Relative Risk (Matched Control)* Lower Limit Upper Limit
Weeks to First Observed Tumor
P - 0.031 105
4.000 0.437 187.475
105
0.000 0.000
18.289
--
0.000
o.ooff
18.289
_'
MOMS 00031?
Table C2. Analyses of the Incidence of Primary Tumors in Fetiale Rats Fed Aroelor 1254 in the Diet*
ToDoaraohv: MoroholoRv
Matched Control
Low Dose
Hid Dose
High Dose
Uterus: Endometrial Stromal Polypi
P Value.0-11
Relative Risk (Hatched Control)1 Lower Limit Upper Limit
Weeks to First Observed Tumor
2/24 (8) N.S.
105
5/24 (21)
N.S.
2.500 0.459 24.045
100
5/24 (21)
N.S.
2.500 0.459 24.045
103
3/24 (13)
N.S.
1.500 0.188 16.583
96
*Treated groups received doses of 25, 50, or 100 ppm.
^Number of tumor-bearing animals/number of animals neeropsied (percent).
cBeneath the incidence of tuaora In the control group is the probability level for the CochranArmltage test when P < 0.05; otherwise, not significant (N.S.) is indicated. Beneath the inci dence of tumors in a treated group is the probability level for the Fisher exact test for the comparison of that treated group-with the matched-control group when P < 0.05; otherwise, not significant (N.S.) is indicated.
negative trend (N) indicates a lower incidence in a treated group than in the control group.
*The probability level for departure from linear trend is given when P < 0.05 for any comparison.
iphe 951 confidence Interval of the relative risk between each treated group and the matchedcontrol group.
HONS 000318