Document jBwz8BRGb45B7N6k96Gx40VJQ

ASSESSMENT 0? ME BIOLOGICAIl PERSISTENCE DR POLYCHLORINATED BIPHENYLS By Dr. E. S. Tucker Presented by W. B.Papageorge Tho research I will review today will focu3 ii[ion one aspect of lion- ' Bento's efforts to understand the environmental impact and behavior of our polychlorinated biphenyl or VOH products. This research was initiated early in I960 after development of the necessary PCB analytical methodology and subsequent confirmation of Dr. Boren Jensen's identification of PCB residues in fish and birds in Sweden. At this point in time, PCB residue data from Monsanto and oxternal environmental monitoring programs indicated that at the previous rate of use and release- of these products that some PCB homologs were beginning to reach detectable levels in fish, birds and mammals. Conversely, these data indicated to u^ that with the exception of localized, controllable contamination, PCB liomologs with less than five chlorine atoms per molecule had not accumulated to detectable levels; even though it was known that significantly greater amounts of the PCB homologs with less than 5 chlorine atoms per molecule had been manufactured and used over the years. How, before discussing our biological studies, I would like to review for you the gross homolog composition of our Aroolor products and then in a very brief fashion, try and illustrate to you the complexity of these materials and hence the complexity of the problem. ' In the first slide (ID, is shown the most recent data on the weight % composition of four of our Aroclor products as a function of each detectable PCB homolog. The first column on the left lists the homolog in question and the subsequent columns under each product show the weight t distribution of each PCB homolog in each product. As most of you probably know, with the exception of Aroclor 1016, the last two digits of each product number refer to the degree of chlor ination. For example, Aroclor 1221 contains 21% chlorine by weight, and so on. Aroclor 1016 is a special case in that while it contains about 41% chlorine by weight, its penta, hexa, and heptachloro biphenyl content has been significantly reduced with respect to Aroclor 1242, a product produced by direct chlorination, containing 42% by weight chlorine. Please note that the penta, hen, and heptachloro biphenyl homologs in Aroclor 1016 have been reduced by factors of about 8, 10, and 10, respectively, with reference to Aroclor 1242. As you can also see, the chief constituents of Aroclor 1221 are the mono- and dichloro biphenyls, while Aroclor 1016 and Aroclor 1242 contain predominantly di-, tri-, and tetrachioro biphenyls, and Aroclor 1254, tetra, penta, apd hexacJiloro biphenyls. . MONS 044006 As I indicated ra-.-l3.er, 'this table represents our most recent efforts at determining the homolog distribution of our V-Cl) products end us unch q number of you may Imvo seen estimations of the homolog content of these products which ere significantly different, Tho analytical methodology used in currently in a very dynamic state and our understanding of the contents of those products increases as the methodology is improved. At this point in time, pe regard those numbers as tho most accurate ones currently available. In the next slide (S2) are shown examples of low resolution - packed column electron capture chromatograms of Aroclor 1221, Aroclor 1242, Aroclor 1254, and Aroclor 1260. This is what these products look like to a residue analyst using the most commonly employed detection system. From these chromatograms,,it can be readily seen that we are dealing with multi-component products, yhich of course, increases the com plexity of assessing every aspect of this problem - relative to a well defined single component system such as DDT. I should mention at this point, that tho PCB residues generally found in wildlife are most similar to Aroclor 1254 and Aroclor 1260 chromatograms. The next slide (13) demonstrates that in reality, these materials ore even more complex than is generally realized. In the upper right portion of this slide is again shown a low resolution electron capture gas chromatogram of Aroclor 1242 under the optimum conditions normally employed by residue analysts. Under these conditions, Aroclor 1242 would appear to be a 15 component system. In the lower portion of this slide is a flame ionization gas chromato gram of the same material using a high resolution S.C.O.T. column. If one carefully inspects this chromatogram, our simple 15 component product has now been resolved into SS different components. These facts simply indicate that all PCB products cannot be lumped together in terms of either their environmental impact or persist ence. ' The type of biological studies which we have carried out to date are shown in tho next slide (15). For discussion purposes, they can be conveniently divided into two categories: "Primary Bacterial Degradation Studies", an area in which research on PCBs is just beginning, and "Residue Accumulation Studies". Most of our bacterial degradation work has beeh centered around the fairly well known semi- eontinuous activated sludge degradation test. Our residue accumulation studies have been fairly extensive and have Involved the exposure of better than 2100 fish, chickens, rats and dogs to the various Aroclor products: resulting in the collection of over 1200 samples of which approximately 500 pooled samples were eventually analyzed for PCB residues. The prime objective of these studies is given on slide 16. HONS 044007 r.lid-5 *1. The sc;-..l-continuous activated uludgr tost procedure wo wood to evaluate the primary bacterial degradation rates of the hroclur products is the tent method recommended l>y the Soap and Detergents Association for the evaluation of the biodegradability or linear nlkyl benzene sulfonate type surfactants [JAOCS 42, 986 (1965) t 46, 432 (1969)). Primary Biodegradation - Minimum alternation of the chemical structure of the material in question to an extent that characteristic properties of the origina'l material are no longer evidont. This procedure employs sludge from a sewage treatment plant as the ouree of microorganisms to which a specific amount of the material boing evaluated and a synthetic sewage mixture ara fed on a periodic basis in a specially designed aeration chamber. The next slide (18) graphically illustrates what the aeration chamber looks like. It is simply a large glass cylinder with provisions for aeration, auxiliary stirring, a siphon for periodic removal of the supernatant and a septum for introduction of the test material. The mixed liquor (sludge + water) obtained from the sewage treatment plant is initially adjusted with tap water to a suspended solids concentration of about 2500 mg/1, and 1500 ml of this mixture is then charged to the aeration chamber. The mechanical cycle employed is shown in the next slide (19). Each cycle is initiated by tho addition of the synthetic sewage and 1 mg of the PCD product being tested. Since the PCBs are quite water insoluble, they are fed to the unit via injection of 200 pis of a concentrated ethanol solution. In this manner, homogenous dispersion of the PCBs on the bacterial sludge is obtained. After about one hour of aeration an aliquot of the mixed liquor ia withdrawn from the chamber and analyzed for PCBs via UV spectro photometry and/or electroh capture gas chromatography. Aeration is continued for about 48 hours and a second sample is withdrawn for analysis. At this point, the aeration is stopped and the sludge allowed to settle, the sludge volume and pH are then checked to insure that the unit is operating satisfactorily. Two-thirds of the supernatant is withdrawn and replaced with tap water; aeration is then resumed. The cycle is re-inltiated by the addition of the synthetic sewage and Aroclor in question. This cycle is continuously repealed until a steady state and consistent degradation rates are obtained. The per cent degradation rate is calculated as shown in the equation on the slide from the amounts found in the samples analyzed during each cycle. ,. Degradation testing of the Aroclor products shown in the next slide ((10) have been carried out over an eight month period in our laboratories. In this slide, we have shown graphically the results observed to date. Here we have plotted the mean per cent degradation HONS 044008 jetton for biphenyl, Aroclor 1221, MCft 1043, n ronr.irch material coin .itnti*<i 301 l>v weight chlorine, hi uclor 101C (111 chlorine), ArocJ or 1342, and Aroclor 1254 versus the weight per cent chlorine prensnt in each. The actual moan per cent degradation rates and 95" confidence limits for each material are shown in the lower loft: portion of the slide. These data were all obtained by UV spectro photometry which in essence follows the decrease in the aromatic ring content and is indicative of bacterial ring cleavage. The important point to note here is that as the degree of chlorination decreases the degradation rate increases. In order to give you a feeling for the degradation rates observed with other materials, Aroclor 1221 degrades at about the same rate as a non-linear ADS surfactant. We have also used this technique to study p,p'-DDT and have at this point in time noted no significant primary degradation. The next slide (til) shows the changes in homolog distribution observed for Aroclor 1242 via electron capture gas chromatographic analyses. The upper chromatogram shows the character of the residue one hour after eddition. The numbers above each peak indicate the dominant homolog or homologs present in each. The lower chromatogram is of the residue after 72 hours of exposure to the bacterial sludge. It can be readily seen by comparing the two chromatograms that all the dichloro biphenyls, most of the trichloro biphenyls, and a significant portion of the tetrachloro biphenyls are degraded in 40 hours under these test conditions. The conclusions which we draw from this preliminary data are shown in the next slide (412). Next, I will discuss our "Aroclor Residue Studies" (Slide 13). Our white leghorn chicken studies (Slide 114) have consisted of a 90 day oral exposure, of Aroclor 1242, Aroclor 12S4, and Aroclor 1260 at 1, 10, and 100 ppm feed levels and a repeat 90 day study of Aroclor 1242 at the 2, 4, and 8 ppm feed levels. 336 Chickens were employed from which a total of 521 tissue, chick, and egg samples were collected. Of these 112 pooled samples were analyzad for PCB residues. In the next slide (tl5) are shown the results of the 90 day oral exposure of white leghorn chickens to Aroclor 1242. On the left side, we have shown the oral exposure levels which were 1, 10, and 100 p;?m, the theoretical residue in ppm, which would have been found in the lipid if the chickens had retained all of the Aroclor 1242 which they orally injested. As you can see, these levels are *125, 1250, and 12,500 ppm. Next is shown the actual avarage level In ppm found in the lipid of the muscle, fat, and liver samples and then the levels found after 30 days on a PCB free diet. The important points to note are that ,v90i of all the Aroclor 1242 consumed is directly excreted and/or metabolized and that after 30 days wn a PCB free diet 35*, 441, and 571 of the PCBs retained after 90 days of continuous exposure at the 1, 10, and 100 ppm levels was excreted and/or metabolised. HONS 0^4009 On the right ham: nide of this slide is shown the homclog distri bution of the product fed and that of the residues isolated from tho tissues after 90 days of exposure and 30 days on a pcb free diet.1' Tho numbers across the top simply refer to the number of chlorine atoms per biphenyl molecule. As you can see, Aroclor 1242 contains dominant amounts of the di- through pcntachlorobiphenyls and a'minor amount, of hexachloroblphenyl. After 90 days of exposure the d.ichlorobiphenyl was no longer observable and the dominant components were the tri- through pentachloro biphenyl homologs. After 30 days on a PCB free recovery diet, the'hoxacltloro biphenyl is now a dominant component because of continued excretion and/or metabolism of the lower chlorinated homologs. In the next slide (116) are shown the results for the 90 day oral exposure of Aroclor 1254 in white leghorn chickens at the 1, 10, and 100 ppm exposure levels. The theoretical residues are the seme as before and we have againshown the actual levels found in the tissues after 90 days of continuous exposure and 30 days on a PCB free diet. In this instance, ^70-721 of the Aroclor 1254 ingested was directly excreted and/or metabolized and after 30 days on a PCB free diet, ^45% of the residues retained were excreted and/or metabolized. The homolog distribution of the product and residues is shown on the right of the slide,'the product Aroclor 1254 contains minor amounts of the tri- and heptachloro homologs and dominant amounts of the tetra-, ponta-, and hexachtoro biphenyls. The residue after 90 days of exposure did not contain detectable amounts of the tri- chloro biphenyls and the tetrachloro biphenyls were no longer a dominant component. The dominant homologs were penta- and hexa- chtoro biphenyls. After 30 days on a PCB free diet, the tetra- chloro biphenyls were now not detectable, the pentachloro biphenyls were a minor component, and the hexachloro biphenyls the dominant component. ( In the next slide (117) are the results for Aroclor 1260. Again, tho oral exposure level and theoretical rosidue levels are the ame and the PCB residues found in the tissues after 90 days of continuous exposure and 30 days on a PCB free recovery diet are shown. After 90 days of exposure, 57-52% of all Aroclor 1260 consumed, was directly excreted and/or metabolized and after 30 days on h PCB free diet t>40% of the residues retained were excreted and/or metabolized. As shown on the right, Aroclor 1260 contains dominant amounts of penta-, hexa-, and heptachloro biphenyls and a minor arount of ootaehioro biphenyl. The residues after 90 days of exposure and 30 days on a PCB free recovery diet contain minor amounts of the pentaand Ootaehioro homologs. In both cases, the dominant nomologs ware the hexa- and heptachloro biphenyls. Our albino rat work (Slide 118) has consisted of 30 day oral, 2 year chronic oral and a 3 generation rat reproduction exposure study with Aroclor 1242, Aroclor 1254, and Aroclor 1260 and a 90 day subacute HONS 044010 oi. al exposure of A roc lor 1221. Approximately 1400 animals were lined in those exposure studios from which ubout 400 rausclo, livor, and fat samples wore collected. Two hundred of those samples were analysed for PCD residues. In tho next tilde (119) arc shown the results of our two year chronic oral exposure* study of Aroclor 1242 in albino rats. The oral exposure levels were 1, 10, and 100 ppm and the theoretical residues were i.80ll, 8000, 80,000 ppm, respectively. The actual residues found in the tissue lipid are shown after 3, 12, and 24 months of exposure. Comparison of the residues found after 24 months to the theoretical residue levels indicates that 99% of the Aroclor 1242 fed was directly excreted and/or metabolized at all exposure levels. At it shown on the right, Aroclor 1242 contains dominant amounts of the di- through pentachloro biphenyl homologs and a minor amount of tho hexa-. The residues after two years did not contain a signifi cant amount of the dichloro biphenyls and the dominant components were the tri-, tetra-, and pentachloro biphenyl homologs. In the next slide (120) are shown tho results of the two year chronic oral exposure of albino rats to Aroclor 1254. The exposure and theoretical residue levels are the same as with Aroclor 1242. The residues found after 3, 12, and 24 months of exposure are also shown. Comparison of the residues after two years to the amount ingested demonstrates that 95-98% of the Aroclor 1254 consumed is directly excreted and/or metabolised. The homolog distribution of Aroclor 1254 and the residues are shown on the right. Aroclor 1254 contains minor amounts of the tri- and heptachloro biphenyl homologs and dominant amounts of the tetra-, penta-, and hexachloro biphenyl homologs. The residues did not contain detectable levels of the trichloro homologs and the tetrachloro biphenyls were no longer a dominant component. The dominant homologs were the penta- and hexachloro biphenyls. The next slide (121) Shows the the results for the two year exposure of Aroclor 1260 in albino r.ats. Again, the exposure and theoretical residue levels are the same and the residues found in the tissues after 3, 12, and 24 months of exposure are .shown. In this ease 93-95% of all Aroclor 1260 ingested was directly excreted and/or metabolized. The dominant homologs in Aroclor 1260 and the residues isolated from the tissues were similar in all cases. In order to demonstrate the relationship between residue storage levelr and the degree of chlorination of the product fed (slide (22). I have plotted the average ppm PCD found in the lipid vs the weight per cent chlorine in the product fed. These data were taken from our 90 day subacute albino rat studies with Aroclor 1221, Aroclor 1242, Aroclor 1254, end Arekfto,)taJ.260 at an exposure level of 100 ppm. As you can ses, the residue,iitajVjhge levels decrease exponentially as the weight per cent chlorine (WwSreasom, simply demonstrating the relationship between the hipbftr' homolog content of an Aroclor product and the tissue stotpgp level. HONS 044011 Our beagle dog studios (slide 23) have consisted of a two year chronic exposure of Aroclor 1242, Aroclor 1254, and Aroclor 1260 and a 30 day subacute study of Aroclor 1221. In these studies, .1.08 beagle dogs were used, resulting in the collection of 263 samples, and the analyses of 146 for PCB residues. * The next slide (24) shows the results of one two year"study of Aroclor 1242 at exposure levels of 1, 10, and 100 ppm. In this Study, the theoretical residue levels are 'vDOO, 5000, and-50,000 ppm respectively. We have also shown on this slide the residue levels found after two years of exposure and after 30 and 60 day periods on PCB free recovery diets. The beagle dogs directly excreted and/or metabolized 99.61 of the Aroclor 1242 consumed and after 60 days on PCB free diets, 50-609 of PCB residue retained after two years of exposuro was excreted and/or metabolized. Aroclor 1242 contains dominant amounts of the di-, tri-, tetra-, and pentachloro homologs and a minor amount of the hexa- homolog. The residue found after two years of exposure contained no detectable lovels of the dichloro homologs and dominant levels of the tri-, tetra-, bepta-, and octachloro biphenyls. The pentachloro homolog, although dominant in the product fed, was not a dominant component of the residue. After 30 days on a PCB free recovery diet, the di-, tri-, and tetrachloro biphenyls were not detectable components of the residue. At this point, the dominant components were the hexa-, hepta-, and octochloro biphenyls. The trend toward excretion and/ or metabolism of the lower chlorinated homologs continued to the extent that after 60 days on the recovery diet the hexachloro biphenyl was no longer a dominant component, and the hepta- and octachloro bi phenyls became the dominant constituents in the residue. In tho next slide (125) arc the results for the two year exposure of beagle dogs to Aroclor 1254: The oral exposure and theoretical residua levels are the same and the PCB residue levels found in the tissues after two years of exposure and after 30 and 60 day periods on PCB free recovery diets are again shown. ' In this instance, the dogs excreted and/or metabolized 98-99% of all Aroclor 1254 consumed over a two year period. After 60 days on a PCB free recovery diet, 30-40% of the residues retained were excreted and/or metabolisod. The product fed, Aroclor 1254, contains minor amounts of the tri- and heptachloro biphenyls and dominant amounts of the tetra-, penta-, and hexachloro homologs. After two years of exposure, the residue retained from the product did not contain detectable levels of the tri- or tetrachloro biphenyls, the penta-, and hexachloro biphenyls remained dominant components, and _ the heptachloro biphenyls became dominant constituents. ' After 30 days on the PCB free recovery diet, tho pentachloro homologs became a minor component of the residue, the hexa- and heptachloro biphenyls remained dominant components and the octachloro homologs becamo a minor component. After 60 days on the PCB free recovery diot, the pentachloro biphenyls were excreted and/or metabolized to the extent that the octachloro homologs became a dominant constituent of the residue. MONS 044012 Tho next slide (4 26) shows the results for the two year oral exposure residue study of Arcelor 1260 in beagle dogs. The exposure and theoretical residue levels arc the same as those for the Aroclor 1242 and Aroclor' 1254 studies. Next is shown the residues which accumulated after two years of continuous exposure and the residues rntainod aftor 30 and 60 day recovery periods on PCB free diets. With this Aroclor 98-99* of the amount consumed over two years was directly excreted and/or metabolized. After 60 days on the recovery diet 4,13% of the retained residues were excreted and/or metabolized. The homolog distribution of Aroclor 1260 is as shown, dominant amounts of the penta-, hexa-, and heptachloro biphenyls with a minor amount of the octachloro homologs. After two years, the PCB residue contains no detectable level of the pentachloro homologs, a minor amount of the heptachloro biphenyls, and dominant amounts of the hoxachloro and octachloro homologs. After 30 days on the recovery diet, the dominant homologs are now the hexa-, hepta-, and octa chloro biphenyls becoming a dominant component of the residue via loss of some of the hexachloro biphenyls. After 60 days on the recovery diet, the hexachloro biphenyls are no longer dominant components of the residue and it is now mainly the hepta- and octachloro biphenyls. The next slide (127) illustrates the residue fall off as a function of Aroclor and recovery period. These data are from the two year beagle dog studies and tho exposure level is 1 ppm. In this graph, X have plotted tho average ppm PCB found in the lipid for Aroclor 1260, Aroclor 1254, and Aroclor 1242 after two years of continuous oral exposure and then after 1 month and 2 month recovery periods on PCB free diets. This plot simply demonstrates that the PCB residues retained from Aroclor 1242 fall off more quickly than those retained from Aroclor 1254 and Aroclor 1260. The table in the next slide (128) shows the relative ability of fowl, mall mammals, and large mammals to retain orally ingested PCBs. These data are for Aroclor 1242 at the exposure levels and periods shown. The concentration factor is calculated by dividing the maximum PCB level found in 'the lipid by the exposure level. As you can see from the factors, chickens retain PCBs to a greater extent than do rats or dogs. Our fish residue work is not very extensive at this point - primarily because we have had problems in finding consulting laboratories capable of carrying out dynamic low level fish exposure studies, and secondly, because government laboratories such as those in Duluth, Minnesota, Columbia, Missouri, and Gulf Bree*e, Florida were, and are, still in better positions to carry out and evaluate these types of studies. Me have done some very preliminary 21 day dynamic exposures of cat fish and bluegill fingerlings to some of our Aroclor products and it generally supports the conclusions which can be drawn froai literature data. ; The general conclusions which we draw from these residue studies are shown in the next three slides. MONS 044013 SiIdo 129 - Build-Up - Conclusions Slide 130 - Pall-Off - Conclusions Slide 131 - Alteration of Homolog Distribution - Conclusions In summary, we feel that the results of our preliminary research It support, what has and is being observed via residue analysis of environmental samples; that is to say, from a residue viewpoint, that the bulk of the PCB homologs released to the environment (PCBs [r with less than 5 chlorines) are subject to environmental degradation j, of one sort or another at measurable rates and as such have not accumulated. I. S. tucker I i: I: I! t HONS 044011* TYPICAL % COMPOSITION OF POLYCHLORINATED BIPHENYL PRODUCTS HOMOLOG # Cl/BIPHENYL 0 1 3 4 S 6 AROCLOR 1221 11 51 32 4 2 <0.5 ND HD ND AROCLOR 1016 <0.1 1 20 57 21 1 <0.1 NO ND AROCLOR 1242 <0.1 1 16 49 25 8 1 <0.1 NO AROCLOR 1254 <0.1 <0.1 <0.5 1 21 48 23 6 ND PER CENT (N/W) BY 6C/HASS US1N6 AREA CORRECTION FACTORS BY HON0L06 RESPONSE NONE DETECTED, <0.01S - NO HONS 044015 Electron Capture Gas Chromatograms Aroclor 1221 Ejution Time (minutes) HONS 044016 Aroclor 1242  PCB PRODUCTS ARE NOT A SIN6LE ENTITY, BUT COMPLEX MULTI COMPONENT MIXTURES PCB RESIDUES FOUND IN MILD LIFE ARE DOMINANTLY PENTA-, HEXA-, HEPTA-, AND OCTACHLORO BIPHENYLS PCB RESIDUE ARE MOST SIMILAR TO AROCLOR 1254 AND AROCLOR 1260 PRODUCTS HONS 044014 PRIMARY BACTERIAL DEGRADATION STUDIES SEMI-CONTINUOUS ACTIVATED . SLU06E DEGRADATION RESIDUE ACCUMULATION STUDIES FISH - CATFISH AND BLUEGILLS BIRDS - WHITE LEGHORN CHICKENS MAMMALS - ALBINO RATS AND BEAGLE D06S MONS 044019 ASSESSMENT OF THE PERSISTENCE OF POLYCHLOMNATEP BIPHENYLS IN PI0L06ICAI SYSTEMS I HONS 044020 AROCLOR SEMI-CONTIHUOUS ACTIVATED SLUDGE PRIWARr DEGRADATIOH STUOIES HONS 044021 Semi-Continuous Activated Sludge Test Unit Stirrer HONS 044022 i' MECHANICAL CYCLE SYNTHETIC SEWAGE AND AROCIOR (lmg) ADOED HONS 044023 Semi-Continuous Activated Sludge Degradation of Polychlorinated Biphenyls 1 u W x: QO 2 60 Aroelor % Pegrodotion o Biphenyl 100.0 e Aroclor 1221 80.6 1 5.7 ? MCS 1043 56.2 15.5 20 - Aroclor 1016. 32.9113.8 K Aroclor 1242 26.3115.5 Aroclor 1254 15.21377 < Addition rote 1mg/48 hrs ____L__ J____L.____ 1_____J______; 10 30 30 Aroclor' 1242 40 % Chlorine (%) 30 HONS 044024 Semi-Continuous Activated Sludge Degradation of Aroclor 1242 HONS 044025 BACTERIAL DEGRADATION STUDIES CONCLUSIONS RATE OF PRIMARY DEGRADATION INCREASES AS THE DEGREE OF CHLORINATION OF THE AROCLOR PRODUCT DECREASES BI PHENYL>AROCLOR 1221>MCS 1043 >AROCLOR 1016>AR0CL0R 1242>AR0CL0R 1254 BIPHENYL, MONO-, DI-, TRI-, AND TETRACHLORO BIPHENYL HOMOLOGS UNDERGO PRIMARY BACTERIAL DEGRADATION HONS 04402b AROCLOR RESIDUE STUDIES HONS 044027 WHITE LEGHORN CHICKEN STUDIES PRODUCTS STUDIED NUMBER ) OF } CHICKENS) FEMALE MALE. NUMBER) OF } samples) MUSCLE LIVER FAT EG6S CHICKS NUHBfcR) OF J samples) analyzed) MUSCLE LIVER FAT CHICKS 90 DAY ORAL AROCLOR 1242 AROCLOR 1254 AROCLOR 1260 AROCLOR 1242 ZOO 80 40 16 40 40 40 *250 30 a a a 4(0 10 . 14 12 IS 25 n 5 4 5 8 10 TOTAL SAMPLES COLLECTED TOTAL ANALYZED 400 80 121 32 ORAL EXPOSURE CARRIEO OUT BY INDUSTRIAL BIO-TEST LABORATORIES. INC. NORTHBROOK. ILLINOIS HONS 044028 RESIDUE STUDY OF AROCLOR 1242 IN WHITE LEGHORN CHICKENS 90 DAY ORAL HOMOLOG DISTRIBUTION MR- PCBs 123456789 ORAL EXPOSURE LEVEL 1 10 100 10 tTHEORETICAL RESIDUE 126 .1260 12602 - (2) (3) (4) (5) 6 - - - RESIDUE, 12 NEEK 14 136 1312 - - (3) (4) (5) 6, - - EXPOSURE RESIDUE, 30 OAT RECOVERY 9 77 749 - - (3) (4) (5) (6) - - - tIF TOTAL PCB CONSUMEO HERE RETAINED AVERAGE PPN IN LIPIO - ALL TISSUES ( )ELECTRON CAPTURE PEAKS GREATER THAR 5X OF TOTAL HONS 044029 RESIDUE STUDY OF AROCLOR 1254 IN WHITE LEGHORN CHICKENS 90 DAY ORAL H0H0L06 DISTRIBUTION PM PCBs 1 234567 8 9 ORAL EXPOSURE LEVEL 1 10 100 10 tTHEORETICAL RESIDUE 126 1260 12602 - - 3 (4) (5) (6) 7 - - - "RESIDUE. 12 WEEK EXPOSURE "RESIDUE. 30 DAY RECOVERY 38 362 3 $06 - - - 4 (5) (6) 7 - - ...17 164 1580 - 5 (6) 7 - - - tIF TOTAL PCB CONSUMED MERE RETAINED "AVERAGE PPM IN LIPID - ALL TISSUES ( )ELECTRON CAPTURE PEAKS GREATER THAN 5* OF TOTAL HONS 044030 RESIDUE STUDY OF AROCLOR 1260 IN WHITE LEGHORN CHICKENS 90 DAY ORAL HONOLOG DISTRIBUTION PPM PCBs 1 2 3 4 5 6 7 8 9 10 ORAL EXPOSURE LEVEL 1 10 100 tTHEORETICAL RESIDUE 126 1260' 12602 - - - - (5) (6) (7) 8 - - `RlfsiD'JF. 12 MEEK EXPOSURE `RESIDUE. 30 DAY RECOVERY 65 607 5909 - - - - S (6) (7) 8 * 26 232 2363 - . . - 5 (6) (7) 8 - - tIF TOTAL PCS CONSUMED MERE RETAINED AVERAGE PPM IN LIPID - ALL TISSUES ( )ELECTRON CAPTURE PEAKS GREATER THAR 5* OF TOTAL HONS 0*4031 ALBINO RAT STUDIES PRODUCTS STUDIED NUMBER]) FEMALE OF rats!) MALE 30 DAY ORAL AROCLOR 1242 AROCLOR 1254 AROCLOR 1260 115 115 2 YEAR CHRONIC ORAL AROCLOR 1242 AROCLOR 1254 AROCLOR 1260 500 500 3 GENERATION RAT REPRODUCTION AROCLOR 1242 AROCLOR 1ZS4 AROCLOR 1260 *20 -v.20 90 DAY SUBACUTE ORAL AROCLOR 1221 60 60 MUSCLE number;) KIONEY 0F \ LIVER samples!1 FAT PUPS 18 18 18 18 " 33 - 33 33 - 10 7 7 7 - NUMBER],! MUSCLE KIONEY OF SAMPLES ANALYZED]1 LIVER FAT PUPS 18 18 18 18 1MB 33 33 33 -MM* 10 7 7 7 TOTAL SAMPLES COLLECTED 144 198 20 TOTAL ANALYZED 72 99 10 42 21 ORAL EXPOSURE CARRIED OUT BY INDUSTRIAL BIO-TEST LABORATORIES, INC. NORTHBROOK, ILLINOIS HONS 044032 RESIDUE STUDY OF AROCLOR 1242 IN ALBINO RATS TWO YEAR CHRONIC ORAL EXPOSURE HOMOLOG DISTRIBUTION ORAL EXPOSURE LEVEL PPM PC8S J____ I____ 3____ ____ 5_ _6____ Z____ I____ ?____ 1 T 10' "TOT" tTHEORETICAL RESIDUE 003 8037 80373 - (2) (3) (4) (5) 6 - - - - RESIOUE. 3 MONTH EXPOSURE 6 23 90 - - (3) (4) (5) 6 - - - - RESIDUE. 12 MONTH 9 37 155 - - (3) (4) (5) 6 - - - EXPOSURE RESIDUE. 24 MONTH 12 53 240 - - (3) (4) (5) 6 - - - EXPOSURE tIF TOTAL PCS CONSUMED MERE RETAINED AVERAGE PPM IN LIPID - ALL TISSUES ( J ELECTRON CAPTURE PEAKS GREATER THAN 5* OF TOTAL HONS 344033 RESIDUE STUDY OF AROCLOR 12 5A IN ALBINO RATS TWO YEAR CHRONIC ORAL EXPOSURE HONOLOG DISTRIBUTION PPN PCBs 1 2 3 4 5 6 78 ORAL EXPOSURE LEVEL 1 10 100 tTHEORETICAL RESIDUE 803 8037 80373 - 3 (4) (5) () 7 - RESIDUE, 3 NORTH 13 94 679 - - - 4 (5) (6) 7 EXPOSURE 9.10 --- RESIDUE, 12 NORTH 24 189 1471 EXPOSURE RESIDUE, 24 NORTH 42 355 3038 - - - 4 (5) C6) 7 - - . . 4 (5) (6) 7 - - - tIF TOTAL PCS COHSUHCD HERE RETAINED *AVERAGE PPN IN LIPIO - ALL TISSUES ( )ELECTRON CAPTURE PEAKS GREATER THAN SS OF TOTAL HQNS 044034 RESIDUE STUDY OF AROCLOR I2>60 IN ALBINO RATS TWO YEAR CHRONIC ORAL EXPOSURE ORAL EXPOSURE LETEL PPM PC6s 1 10 100 1 H0H0L06 DISTRIBUTION 2 3 4 5 6 7 8 9 10 -- tTHEORETICAL RESIDUE 803 8037 80373 - - - (5) (5) (7) 8 - - RESIDUE. 3 MONTH 18 134 970 - - - - (5) () .<*> 8 EXPOSURE - RESIDUE. 12 MONTH 35 270 2099 - - - - (5) (6) (7) 8 EXPOSURE - RESIDUE, 24 MONTH 59 507 4338 - - - - (5) (6) (7) 8 EXPOSURE - tIF TOTAL PCS CORSUMEO HERE RETAINED AYERA6E PPM IN LIPID - ALL TISSUES ( )ELECTRON CAPTURE PEARS GREATER THAN 5S OF TOTAL MONS 044035 Average ppm PCB In Lipid (Muscle, Fat, Liven BEAGLE DOG STUDIES PRODUCTS 9TUDIE0 NUMBER ) FEMALE OF DOGS) MALE NUMBER ) MUSCLE OF ) LIVER SAMPLES) FAT TOTAL SAMPLES COLLECTED 2 YEAR CHRONIC ORAL AROCLOR 1242 AROCLOR 1254 AROCLOR 1250 40 40 54 54 54 MM 242 90 DAY SUBACUTE ORAL AROCLOR 1221 14 14 7 7 7 MM 21 NUMBER OF ) ) MUSCLE LIVER SAMPLES ANALYZED) FAT 42 40 43 7 7 7 TOTAL ANALYZED 125 21 ORAL EXPOSURE CARRIED OUT BY INDUSTRIAL BIO-TEST LABORATORIES. INC. NORTHBROOK, ILLINOIS HONS 044037 RESIDUE STUDY OF AROCLOR 1242 IN BEAGLE DOGS TWO TEAR CHRONIC ORAl EXPOSURE PPM PCBs HONOLOG DISTRIBUTION 12 3 4 S B 7 8 9 10 ORAL EXPOSURE LEVEL 1 10 100 tTHEORETICAL RESIDUE 519 5186 51865 - (2) (3) (4) (5) 6 - - - `RESIOUE. 2 TEAR EXPOSURE 6 12 - - (3) (4) 5 6 (7) (8) - - `RESIDUE, 30 OAT RECOVERT 1 4 10 (6) (7) (8) - - `RESIDUE, 60 OAT RECOVERT 0.8 (7) (8) - - +IF TOTAL PCS CONSUMED MERE RETAINED "AVERAGE PPM IN LIPID - ALL TISSUES ( )ELECTRON CAPTURE PEAKS GREATER THAN 5X OF TOTAL HONS 04*038 RESIDUE STUDY OF AROCLOR 1254 IN BEAGLE DOGS TWO TEAR CHRONIC ORAL EXPOSURE ORAL EXPOSURE LEVEL PPM PCBs 1 io 100 H0N0L0S DISTRIBUTES 1 2 3 4 5 6 7 a 9 io tTHEORETICAL RESIDUE `RESIDUE, 2 YEAR EXPOSURE RESIOUE. 30 OAY RECOVERY `RESIDUE, 60 DAY RECOVERY 519 5186 51865 - - 3 (4) (5) (6) 7 7 30 132 - - - - (5) (6) (7) 8 5 24 109 - - - - 5 (6) 17) 8 4 20 88 - - - - 5 (6) (7) (8) - - tIF TOTAL PCB COHSUHED MERE RETAINED `Average ppn is lipid - all tissues ( )ELECTROS CAPTURE PEAKS GREATER THAN 5S OF TOTAL HONS 044039 RESIDUE STUDY OF AROCLOR 1260 IN BEAGLE DOGS TWO YEAR CHRONIC ORAL EXPOSURE ORAL EXPOSURE LEVEL tTHEORETICAL RESIDUE PPM PC8s 1 10 100 HOMOLOG DISTRIBUTION 1 234 5 6 7 8 519 5186 51865 - - - - (5) (6) (7) 8 RESIDUE. 2 YEAR EXPOSURE RESIDUE, 30 DAY RECOVERY RESIDUE. 60 DAT RECOVERY 8 63 388 - - - - - <6} 7 () 7 60 363 - - - - - (6) (7) (8) 7 55 337 - - - - - 6 (7) (8) tIF TOTAL PC8 CONSUMED HERE RETAINED AVERAGE PPM IN LIPIO - ALL TISSUES ( )ELECTRON CAPTURE PEAKS GREATER THAN 5X OF TOTAL HONS 0*4040 Two Yeor Chronic Oral Exposure in Boogie Dogs (ot The I ppm Feeding Level) HONS 044041 WHITE IE6H0RN CHICKENS ALBINO RATS BEAGLE OOGS EXPOSURE LEVEL (PPN) EXPOSURE PERIOD 1.0 (FEED) 1.0 (FEED) 1.0 (FEEO) 12 WEEKS 2 VEARS 2 YEARS CONCENTRATION FACTOR* 20 9 2 CONCENTRATION FACTORS DO NOT TAKE INTO ACCOUNT EXPOSURE PERIODS NONS 044042 CONCLUSIONS . RESIDUE BUILDUP STUDIES FOR ALL PRODUCTS THE PCB RESIDUE LEVEL IRCREA5E0 AS THE EXPOSURE LEVEL AHD PERIOD IHCREASED RELATIVE TO AROCLOR 1260, THE HIGHEST CHLORIHATED PRODUCT STUDIED, THE PCB RESIDUE LEVEL DECREASED EXPOHEHTIALLY AS AS THE WEIGHT X CHLORINE OF THE PRODUCT DECREASED RELATIVE LEVELS OF PCB RESIDUES FOUND WERE FISH>CHICKEN$>RATS>DOG$ RELATIVE PCB RESIDUE LEVELS IN TISSUES WERE CHICKENS RATS DOGS FAT - HUSCLE>LIVER LIVER>FAT MUSCLE>KIDNEY LIVER>FAT MUSCLE FOR ALL PRODUCTS THE DOGS AND RATS EXCRETED AND/OR METABOLIZED 93 TO 99X OF THE TOTAL AROCLOR ORALLY INGESTED CHICKENS EXCRETED AND/OR METABOLIZED PRODUCTS INJESTED ORALLY AS FOLLOWS - 90S OF AROCLOR 1242 70S OF AROCLOR 1254 SOS OF AROCLOR 1260 HONS 044043 CONCLUSIONS RESIDUE FALL-OFF DOGS AND CHICKENS CONTINUED TO EXCRETE AND/OR METABOLIZE PCB RESIDUES, INCLUDING PENTA AND HEXA HOMOLOGSt RETAINED WHEN PLACEO ON PCB FREE RECOVERY DIETS D0GS> CHICKENS RELATIVE RESIDUE FALL-OFF RATES SHOWED DOGS: AROCLOR 1242>AROCLOR 1254 >AROCLOR 1260 CHICKENS: AROCLOR 1242>AR0CL0R 1254>AR0CL0R~1260 HONS 044044 CONCLUSIONS RESIDUE STUDIES ALTERATIONS OF AROCLOR HOMOLOO DISTRIBUTION ALTERATION OF THE HOMOLOG DISTRIBUTION OF ALL PRODUCTS HAS OBSERVED IN ALL STUDIES EXCEPT FISH LONER CHLORINATED HOMOLOGS PRESENT IN ALL PRODUCTS HERE PREFERENTIALLT EXCRETED ANO/OR HETABOLIZEO ALTERATION OF THE HOMOLOG DISTRIBUTION INCREASED AS THE HEIGHT t CHLORINE OF THE PRODUCTS DECREASED (INCLUDING PENTA AND HEXA HOMOLOGS) AROCLOR 1221 AROCLOR 124Z>AROCLOR 1254 >AROCLOR 1260 DOGS>RATS>C.HICKENS>FISH