Document 93MmnZoOEwX5ymgMz0R96LDdR

:*ibfn tclmhloridc495(1909). brains and bodies or 1966). alum, and lead. Ann. ifi/.atforr of DOT by 4cnr>ciit; in Japanese odiictiem, and tissue id gross development ) k>, 1974 i ' ; j i i ` [ ^ I 5 5197;; LABORATORY MODEL ECOSYSTEM STUDIES OF THE DEGRADATION AND FATE OF RADIOLABELED TRI-, TETRA-, AND PENTACHLOEOB1HHENYL COMPARED WITH DDE ' R01IERT L. METCALF, JAMES R. SANUORN, PO-YUNC LU nd DONALD NYE Department of Entomology and Environmental Studies Institute, University of Illinois end Illinois Natural History Survey, Urbnna-Champoign Urbana, Illinois 61 SO I Radiolabeled tri-, tetra-, and pcnlachiorobiphcnyls (PCB) and DD1- were studied in a laboratory model ecosystem for degradation pathways, and hiomagnificaiion in alga. snail, mosquito, and fish. Trichlorobiphenyl was degraded in all (he organ isms of the model ecosystem much more rapidly than tctracliloio- and pent.v cliloiobiphcnyl. I'cntachlorobiphenyl W3$ approximately as persistent as DD!:. There was a linear relationship between lipid/watcr partition and ecological magni fication and between water solubility and ecological magnification. No evidence of conversion of DD12 to PCB was detected. The laboratory model ecosvstwm tucviouslv described fMeteali el at. 1971) has been employed for the estimation of the environmental fate of DDT and a number of its analogues (Kapoor ct al. 1970, 1972, 1973) and foi study of aldnn, dicldrin, endrin, mirex, lindane, and hcxachlorobcnzcnc (Metcalf et al. 1973a). The methodology de veloped has yielded useful information about (1) the degradation pathways of the various xcnobiotics, (2) the toxic effects of the compounds and their degradation products, (3) their comparative biomagnification and food chain concentration, and (4) their comparative biodegradabdity; all in organisms of five phyla linked in several food chains. This information has proved of value in characterizing the potential environ mental pollutant effects of candidate insecticides (Kapooi etui. 1973, Coats cl til. 1973) and of plasticizers (Metcalf et al. 1973b). In this paper we report the application of these techniques (o a better understanding of the comparative environmental properties of (rjchloto-, tclrachlorn-, and pcntachloiobiplienyl (1'Clt's), and of dichlotodiphcnyldichlotoclhylenc (i)l)lv) the persistent DDT degradation product. Methods and materials The laboratory model ecosystem evaluation was cauicd out in a small glass aquarium with a sloping terrestrial-aquatic interface of pure white sand exactly as previously de scribed (Metcalf ct al. 1971). The )4C radio labeled compounds were applied quamitalively from acetone solution al 5.0 mg (or ca. one kg per ha) to Sorghum vulgarc seedlings grown in the terrestrial portion. The treated leaves were consumed by fourth tnstar salt Archives et environmental Contamination Ml Totiroiew. Vot. 3. No. 2. IWS 1973 t>y Springer-Ver>j| New Ymk Inc. 151 MQNS Q6ZZ51 152 ' R. L. Mctcnlf et at. marsh caterpillar larvae Estigmene acrea, whose activities and fecal products contaminated tire aquatic portion of the system. The radiolabeled products were transferred through several food chains, c.g., alga (Ocdogonitmi cardincum) snail (Physa)', plankton - water flea (Maphnia magna) -* mosquito {Culex pipiens qumqucfascialus) fish (Gatnbusia afftnis). After 33 days in an eiwiionmcntal chamber at 26C and a 12-hr photoperiod at 5,000 foot candles simulated daylight, the organisms were extracted with acetonitrile and the 14C-radiolabclcd com pounds evaluated by TLC on silica gel containing fluorescent marker (E. Merck CI-254) and radioaulography on no-scrccn x-ray Him. Liquid scintillation counting of the individual components was done in cocktail D (5 g Pl'O and 100 g naphthalene in dioxnne to make one liter) and counts were corrected to dpm by using channels ratio quenching correction. The residues, after extraction, were counted by total combustion to i4C02 by'the Schonigcr oxygen flask technique (Kelly et ai. 1961) to determine the uncxtiaclable radioactivity. Whenever possible, the identity of individual components on the TLC plates was determined by cocluomalography with known standards and by extraction and mass spectrometry. Radiolabeled compounds. The individual nC-labcIcd PCB's were obtained from Mallinkrodt.St. Louis, Missouri. They were: 2,5,2'-trichlorobiphcnyl (2,5-dichlorophcnylrlng-Ulz-i 4C), 9.91 mCi per mmole with > 98% radiopuiity and 41.5% Cl, and a principal constituent of Aroclor 1242 (Webb and McCall 1972); 2,5,2',5,-tetraclilorobiphcnyl (rlng-UL-MC),9.87 mCi per mmole with > 98% radiopurity and 48.7% Cl, and a principal constituent of Aroclor 1248 (Webb and McCall 1972); and 2,4,5,2',5'-pcntachlorobiphcr.y! (2\5,-dtch,'`,f,pb<*nyl.rm.tn,i4f:V 9.87 mCi per mmole with > V8Vb raaio purity and 54.4% Cl, a principal constituent of Aroclor 1754 (Webb and McCall 1972). |4C labeled 2,2-Ws-(p*chIorophcnyl)-l,l*dichlorocthylcnc (DDE) was prepared from |4C*rlng-UL p.p'-DDT obtained from the Radiochemical Centre, Amersham, England, 5.48 mCi per mmole, by dehydrochlorinating with 1.0 M alcoholic KOI!, and purifying on a silicic acid column with hexane elution to 99% radiopurity. Results PCD's. The movement of ,4C radioactivity from Sorghum plants into the water phase of the model ecosystem is shown in Eigute 1. All 11nee diloiirintcd biphenyls reached a maximum concentration in water at about seven days after trcaimnit and (hr levels ol contamination declined as the PCILs were taken up by the organisms of tire system. I he levels of the chlorinated biphenyls in the water phase (Table !) wcic in the ppb rangr:, below tho water solubility of the compounds us determined by radiotracer technique CTablc II). Radioautographs of the extracts from the components of the model system after TLC re shown in Figure 2. The data in Table I represent tire quantitative distribution of the lC in the spots on the TLC plates. The results for the three PCB*s arc also expressed in MQNS 0B2253 r (facts contaminated d chains, e g., alga Daphnia wagm) After 33 days in an X candies simulated (Midiolabcleri com(11. Merck CI-.2M) n counting of the rttlhatcnc in dioxanc eH lalio quenching mbmtion to HC02 rmlnc the uncxnactcomponents on the t standards and by were obtained from | (2,5-dlchlorophcnyl- Cl, and a principal Ktctiachlorobiplicny) 7%Cl, and a principal fc.2\' t Willi * yt-re iagio* .band McCall 1972). a) was prepared from Ameisiiam, England, c KOH, and purifying Degradation of Polychlorinated Biphenyls Compared with DDE 153 Table )I in terms of ecological magnification (E.M.) (ppm in orgnnism/ppm in water) and of biodegradability index (B.l.) (ppm polar dcgiadation producis/ppiu nonpolar products). Tire E.M. values for the parent compounds increased substantially with tire number of chlorine atoms, from trichlorobiphcnyl (41.5% Cl) to tctrachlorobiplicnyl (48.7% Cl) to pcntachlorobiphcnyl (54.4% Cl)- Conversely the B.l. values decreased with Increasing degree of chlorine. This consistent and regular behavior gives added confidence that these parameters are ecologically significant (see Kapoor ct al. 1973) and must be a function of (he number of C-lt bonds available for hydroxylalion by microsomal oxida tions in the various organisms. The spots of low Rf value (0.02-0.06), Figure 2, arc presumably hydtoxylated PCB compounds and the polar radioactivity (Rf 0.0) is thought to consist of conjugates of these compounds. Wallnofer ct al. (1973) have found 4-chloro4'*hytlroxybiphcnyl as a metabolite of 4-chlorobiphcny! from soil fungus, Rhizopus faponicus. Voshimura and Yammnmoto (1973) have reported the 5-hydroxylutcd deriva tive as the major and the 3-hydroxylatcd derivative as the minor excretion product of 2,4,3',4'-tctrachlorobiphcnyl in the rat. Ilutzingcr ct al. (1972) have shown that ratand pigeon could hydroxylatc 2,5,2,5,*tcttnchlorobiplicnyl but they could not detect hydroxylated metabolites in brook trout. However, the amounts of polar material in Gambusla (Figure 2, Table 1) suggest that this fish is able to slowly hydroxylatc this tctrachlorobiphcnyl. H Into lIlC WIC! I'l'ilSfti M|ilwnyk icwIumI a mrnl nml Ike Imeh i'f .vim i>l the ,yium. lire wee In llie I'l'b *`inl'.ci ladioliecci technique node) lyilem tflci T1.C alive diitiibution of the D'l tie elio expicsicd in Fig. 1. Movement of total l4C radioactivity from plants into the water phase of the model ecosystem and uptake by organisms. MQNS oazzs'i Tabic I. Distribution of chlorinated biphenyls and their degradation products in the model ecosystem ll70 Chlorinated biphenyl equivalents (ppm) Oedogonium I'hysa (snail) Culex Camhusia (mosquito) (fWO I. 2,S,2,-lrichlorobiphenyl total 1 Unknown 1 (!tf 0.66a) trlctiiorobiphcnyl (H, 0.56) Unknown II (Rf 0.23) Unknown 111 (Rf 0.10) Unknown IV (Hf 0.06) Unknown V (Hr 0.04) Unknown VI (Rf 0.03) Polar (Rf 0.0) Uncxtractablc 0.03845 0.0001 S 0.00020 0.00005 " 0.00055 0.00040 0.00040 0.02265 0.01405 23.2155 15.9575 1.4630 0.0520 -- ~~ -' 0.0685 0.5185 5.1560 31.2015 18.9720 1.1590 0.6480 0.973S 0.5460 0.2205 0.4410 3.9315 4.3100 2.7030 1.1995 0.1630 + _ " - - 0.4795 0.8610 3.2055 0.2085 1.2800 0.1595 " " ~ 0.9985 0.5590 II. ZfS^'fS'-tctrticMoro biphenyl total MC etrachlorobiphcnyl /. n^gi Unknown 1 (Rf 0.23) Unknown 11 (Rf 0.04) Tolar (Rf 0.0) Unextraclable 0.02065 O 001 TO 0-00005 0.00155 0.01225 0.00S60 23.6845 21.5975 0.3220 0.1030 0.3275 1.3345 53.7465 4 0.7560 0.4360 3.9850 1.2420 14.5335 1 <6.0 rtJ 0.1070 - 0.9670 0.7850 15.50*5 0.0890 - 0.8545 0.3900 in.2,5,2\4',5,-pcntachloiobiphcnyl pcnlachlorobiphenyl (Hr 0.55") Unknown I (Rf 0.46) Unknown II (Kf 0.39) Unknown 1(1 (Hr 0.21) Unknown IV (Rf 0.04) Unknown V (Rf 0.02) Tolar (Rr 0.0) Unextrac table . 0.04340 0.00985 0.00020 0.00015 0.00030 0.00385 0.02055 0.00850 62.4660 53.8440 0.6850 0.5080 0.1425 0.2570 1.6265 5.4330 TLCwilli hexane (Skellysolve B,bp 60-68*0). 633.0165 181.4565 127.6945 587.3545 170.8480 119.7060 8.6210 2.4070 2.5380 2.2490 1.3195 0.5810 1.9365 1.0520 0.3285 0.5000 7.4965 16.5550 8.3040 " _ 2.6745 3.1SS5 *" 0.7450 2.3610 1.4350 154 MONS 082255 Table D. Ecolotical magnification (EM.j and Biodepadabiiity index (BJ.j ofPCB's and DDE compared with wtter solubility and partition coefficient . HjO solubility Partition Chemical * (ppb) coefficient ____Er-olosical magnification (E.M.) Alga Snail Mosquito Fish tri-a-PCB '' 16 7,803 7,315 5,795 815 6,400 tetra-CI-PCB 16 8,126 17,997 39,439 10,562 11,363 pent3*Cl-PCB 19 16,037 5,464 59,629 17,345 12,152 DDE . 13 18,893 11,251 36,342 59,390 12,037 Biodcgrudafcilily index (B.l.) Alga Snail Mosquito Fish 0.30 0.17 0.35 0.60 0.015 0.082 0.076 0.060 0.029 0.027 0.0134 0.019 0.069 0.049 0.033 0.050 156 Tt. L. Metcalf a al. The pcntachlorobiphcnyl with l).l. values of 0.0)9 to 0.027 in fish and snail is very comparable in model ecosystem behavior to I7DT, IU. 0.015 and 0.044 (Kapoor ct al. 1973) and this suggests that the two compounds should behave similarly in the environ ment (Riscbiotigh ct al. 1908). Properties of the tctrachiorobiphcnyl were similar to those of the pcnlachlorobiphcnyl (Figure 2) but the Irichlorobiplicnyl was much more degradable. A prominent degrad,Hive product (Rf 0.66) is stored in alga, snail, and mosquito larva in much greater quantities than the patent compound. This compound is less polai (higher Rf) in the hexane solvent than any of the three I'CB isomers. As shown in Table I it is magnified to very high values, I06.382X in alga ami I26.480X in snail, is Stored in lipids, and is highly persistent. Its presence in high amounts in alga and in the snail and mosquito which are alga feeders suggests that it might lie formed by photo chemical pioccsscs during photosynthesis in the alga. This compound forms slowly and no traces of it wctc visible in three-day uptake studies of trichlorobiphcnyl by alga, snail, daplmia, mosquito or fish (Metcalf and Lu 1973) although it appeared in alga in Fig. 2A. Radioaulogram ofTLCplate con taining extracts of water and organisms (retied with 2,5,2**ltU;htotobiphcnyl. A (alga), F (fish), M (mosquito larva), S (snail) and ST1) (,4C-radiolabclcd com pound). Fig. 2D. RiidioiiuU'gram of TLCpIale con taining extracts of water anti otganisms Healed with Z.S.l'.S'-tctrachJoiohiphvnyl. A (alga), F (fish), M (mosquito larva), S (snail) and STD (MC-radiolabclcd com pound). MONS 08^57 jfeh and nt,ill Is very b.Q44 (Kapoor cl al. itirly in ihc environcnyl were similar to myl was much more I in ilea, snail, and id. This compound is fl Isomers. As shown J36.480X in snail, is its Irt alga and in Ihc !e founed by photoud fotim slowly and Ofobiphcnyl by alga, l appeared in nip,a in Dc&rndnlion of Polychlorinated Diphenyls Comp.trcd with DDU 157 14-day studies. To data we have been unsuccessful in identifying the unknown by mass spectrometry. DD1:. This compound has been implicated as a possible environmental precursor of PCB isomers through photoxid.ition reactions involving radical rearrangements to 3,6-dichlorofluorcnonc intermediates (Plimmer c.l al. 1970, Pcaknll and lincer 1970, Moilanen and Crosby 1973). Although such rearrangements could logically produce, 4,4,-dichlorobiphcny1, it is difficult to see how trichloro- and tctrachlorobiphcnyls could be formed as suggested by Maugh (1973). Moreover, Kernel cf al. (1972) could detect only &/J-(/>-cIilorophcuyl)-ch1otocthylcnc (DDMU) after ultraviolet irradiation of DDE. Because of the ecological importance of these possible rearrangements we have reinvesti gated the behavior of DDE in the model ecosystem (Metcalf ct al. 1971) to determine if any PCB-Iikc products could be formed under the simulated daylight of the model ecosystem (5000 foot candles) in an environmental chamber. The radioautograph show- (?> 0 RID S HyO HjO f M- gum of Tl.CpIntc con* f water and organisms ,$'*lclt#chlo<obilhenyl. M (mosquito larva), S [Mc-radlolabcled com- Pig. 2C. Kadionulogurm of TLCpIatc con taining extracts of water ami organisms treated with ZAS^.S'-pentachlorobiphenyl. A (alga), T (fish), M (mosquito larva), S (snail) and SID (`^'-radiolabeled compound). rig. 2D. Uadinnutnf.iam of T1.C plate con taining extracts of water and organisms treated with DDE. A (alga), 1; (lish), M (mos(|uilo l.nva), S (snail) and STD O^C-rudiolabcIcd compound). MONS 062258 158 R. L. Metcalf ct at. Ing the fate of pure DDF. is presented in Figure 2. When the extracts of water and organisms were developed on TLC plates with Skcllysolvc IJ (hexane fraction) there was no trace of any 1 4C labeled compounds with Rf values between 0.05 and 0.47 (DDF) or of any less polar materials with higher Rf values. Under these conditions, as shown in Figure 2, trichlorobiphcnyl has Rf 0.43, tclrachloiobiphcnyl Rf 0.50, and pcntaehloiobiphenyl Rf 0.53. Detection levels with the techniques used arc approximately 0.1 up (c.g,, spot at alga origin in DDF., Figure 2) or about 0.00002% of the total |4C applied. Thus under the model ecosystem conditions there is no evidence of formation of I'Cll homers from DDF. DDF is extremely stable in the tissues of the living organisms of the model ecosystem and is stored as approximately 92, 93, 9$, and 97% of the total ,4C in snail, alga, fish, and mosquito larva. The percent of uncxtractablc ,4C in these organisms ranged from 0.10 to 0.93 (Table 111). The 1U. value for DDF in fish was 0.049 and the Ii.M. value 12,037 (compared with 0.032 and 27.358 found by Metcalf ei ai. (1971). From these values i( is apparent that DDF is a more stable environmental pollutant than 2.4,5,2',5'pcntachlorobiphenyl (Table- I) which was stored in the organisms at 86 to 94% of the total radioactivity, with from 1.12 to 8.67% of uncxtractablc l4C, and had a B.l. of 0.019 and an E.M. of 12,152 in fish. It is of interest that Soriergren (1973) using a model aquatic ecosystem found no major metabolic changes in DDE occurring in passage through a food chain into fish, although similar experiments with a polychlorinated biphenyl mixture (Clophcn A) thowed that the lower fractions with low chlorine content were degraded when trans ported through the food chain, as was 2,.S,2'*trichlorobiphenyl in uui experiments. How ever, ir. cur studies (Figure 2, Teh!? *'* phasa rrmtnincd several polar radio- Table 111. Distribution of DDE and degradation products in the model ecosystem H,,0 DDK equivalent' (ppm) Oetfogonium Phyta (,IS) (snail) Culex (mosquito) Gamlnt.ua (fish) Total >4C 0.00384 DDF (Hf 0.49") 0.00062 Unknown 1 (K, 0.05) 0.00009 1'olar (Rf 0.0) 0.00223 Uncxtractable 0.0009 7.4720 6.9759 -0.4881 0.0080 38.1958 22.5325 0.8035 1.1612 0.3616 24.8588 36.8223 1.2448 0.1087 7.8653 7.4632 0.3746 0.0275 TLC with hexane (Skcllysolve B, bp 60-68*0. MONS 08^59 ids of water and fraction) tlicrc was and 0.47 (I)IJIO or itlotis, as shown in and pcntachlotobinoxinratcly 0.1 n : total >*C applied, formation of I'Cll re model ecosystem * In snail, elf,a, fish, anlsms ranf.cd from and the R.M. value (1911). From these tint than 2,d.S,2',S it 86 to 94% of the and had a D.I. of i ; ' i ; , j ecosystem fountl no food chain into fish, mlxtuic (Clophcn A) depaded when teenshii experiments. How.ri wvenl nolee taJlo- roducts m) Culex Gainlntiia [mosquito) (fihh) 24.8588 >6.821) 7.8653 7.4632 1.2448 0.1087 0.3746 0.0275 Degradation of Polychlorinated Diphenyl Compared with DDE 159 labeled degradation products. These were resolved on silica gel into at least 11 distinct compounds using a solvent of bcn/.cnc:dioxnnc:acctic acid (90:30:1) and we arc presently attempting to identify the pathway of DDE degradation in the environment. Biomass Recovery. To determine the relative availability of the various organisms of the model ecosystem as reservoirs for the bioaccumulation of the micropollutants studied, the total amounts of 14C`labclcd products recovered from the principal organisms of the model ecosystems treated with tri-, tetra-, and pcnlachloro-PCIJ's, and DDE were evaluated as shown in Table IV, The evaluations were made on the basis of total re* covcry of the applied pollutant, recovery of the maximum amount of pollutant in water (Figuic 1) for each of the four principal organisms, alga, snail, mosquito, and fish; and biomass recovery (four organisms) of the total amount of pollutant lost front water (Figuic 1). The figures of Table IV arc very revealing in terms of the biodegradability of tho various compounds. The highest recoveries of the |4C lost from solution were ob tained from the organisms with DDE, 05.8%, and pcntachlorobiphcnyl, 57.2%. With letrachlotoblphcnyl recoveries of 8.7% were still substantial, but with (richlorobiphcnyl (recovery 0.45%) the compound was nearly completely degraded and excreted. Table IV. Diomass recovery of chlorinated biphenyls, and DDE from organisms of model ecosystem ` % Recovery Alga Snail Mosquito Fish trichlorobiphenyi 14Cin solution 0.18 0.01S total * 4C 0.033 0.0028 ' (biomass) of ,4C lost from solution------ 0.45 0.0017 0.00032 'tetrachlorobiphenyl He in solution 3.33 1.04 0.23 total 4C 0.28 0.088 0.019 (biomass) of I4C tost from solution------ 8.7 pen tacliiorobiph cnyt 4Cin solution 4.57 19.0 2.32 total l<C 0.74 3.06 0.37 (biomass) of 14 C lost from solution------ 57.2 *4C in solution 22.4 4.03 total '4C 0.24 0.044 (biomass) of14 Clost from solution------ 65.8 DDE 2.25 0.055 0.12 0.021 1.91 0.16 11.8 1.90 20.2 0.22 MUNS 082260 160 R. L. Metcalf ct at. . Degradation in Salt Marsh Caterpillar, litis animal was chosen, after considerable study, as the dispersing agent for the model ccosysicm because it was able to ingest a large variety of organic compounds without apparent injury (Metcalf ci al. 197.1). The effects of passage of the PCD isomers through the insect are of interest as representing the first stage in the biodegradation of these compounds. Figure 3 shows radio autographs of TLC plates of extracts of feces and body homogenates from larvae feeding on about 30 /rg of 14C PCD incorporated in a synthetic diet. Figure 3 and the quantitative trl-Ct toWa-CI pontaCI Fig. 3. Radioautogram of TLC plate containing extracts of bodies and feces of salt marsh caterpillar larvae fed ,4C-labclcd 2,5,2'*tri-, 2.5,2',5,*lctra*, and 2,4,5,2',5,-pentachlorobiphenyls. D (body homogenate), and F (fecal excreta). moms 08^61 Lficr considerable It title lo ingest a l Clef. 1973). The h\ M representing c 3 shows radioIrom Ittvtc feeding nd the qunnlilalivc c. F diet and fecet of sail marsh Ad 2,4,S,2',>'*P<aehlro- Degradation of Polychlorinated Biphenyls Complied with DDE 161 evaluation of the radioactivity in the various spots shown in Table V demonstrate con clusively the much greater degradability of the tiicldorobiphcnyl over the tetrachlorobiphenyl and pcntachlorobiphcnyl. With the trichloio-cumpoowl ihc caterpillar feces con tained 91% of lire recovered `'C, with the remainder in rite body homogenate, while with the telraehJoro- and pcnlachlorobiphcnyls, lire feces contained 21% and 24% of the radioactivity. The unknown (Rf 0.05) found in feces after trichlorobiphcnyl is ptobably the principal hydroxylated degradation product leading to the very latgc mount of polar radioactivity. Whereas only low levels of trichlorobiphcnyl were retained hi the salt marsh caterpillar body, with tclrachloro- and pcntachlorobiphcnyl the major portion of1 4C was retained in the insect body. Table V. Metabolism of 1 4C radiolabeled compounds by salt marsh caterpillar* Body Feces A. 2,5,2'-trich!orobiphcnyl total ,4C(%) Unknown 1 (R, 0.53*) trichlorobiphcnyl (Rf 0.43) Unknown 11 (Rf 0,31) Unknown III (Rf 0.13) Unknown IV (Rr0.05) Unknown V (Rf 0.02) Polar (Rf 0.0) B. 2.5,2 ,5 -tcrracniorooipiumyi lot.* ' tctrachlorobiphcnyl (Rf 0.501) Unknown I (Rf 0.41) ' Unknown !l(Rr 0.05) Unknown Ilf (Rf 0.03) Polar (Rt 0.0) (%) C. 2,5,2',4,,5,-pcntachlorobiphcnyl total ,4C(%) ` pcntachlorobiphcnyl (Rf 0.53*) Unknown I (Rf 0.46) Unknown II (Rf 0.39) UftLoewn III (R, 0.03) Polar (Rf 0.0) D. 2,2-6/i-(/>-chtoro|>tcnyt)-1, l -dicMorocdiylunc (1)1)1-) total ,4C (%) * DDE (Rr 0.49) . Polar (Rf 0.0) TLC With hexane (Skcllysolve B, bp 60-<>8*C). 8.66 0.64 5.84 0.27 0.05 ' 0.10 0.11 1.65 78.68 75.60 0.99 0.13 trace 3.96 75.86 74.00 0.74 0.62 0.08 0.42 80.59 76.88 3.71 91.34 8.91 0.37 0.12 4.67 0.92 76.35 71 32 ta.ue 1.36 0.20 4.64 24.14 20.70 0.74 0.56 0.08 2.06 19.41 19.37 0.04 MOWS OSHt* 162 R. L. Metcalf cl al. DDF, passed through the salt marsh caterpillar largely unchanged with 81% of the total radioactivity recovered retained in the body homogenate and 19% in the fecal excreta (Table V). Ecological Magnification. The uptake and concentration of organic compounds by living organisms either directly or through food chains appears to be a function of two important factors, their high lipid solubility and low water solubility, i.c., a large lipid/ water partition coefficient; and their resistance to degradation by enzymatic processes, especially the multifunction oxidase enzymes (Metcalf a al. 1973). Ilamclink ct al. (1971) have suggested that the water Insolubility of highly lipid-soluble compounds piovldcs the driving force in producing lipid storage, through a series of simple partitionings from water to lipids. We have correlated the E.M. values for the I'CH's and DDE from the fish of the model ecosystems with both water solubility (Table II) in Figuic 4, and with the octanol/waler partition value (Table II) in Figure 5. Because the values for the PCB's snd DDE fall closely together, the relationships have been extended using values for aniline, anisolc, benzoic acid, chlorobenzene, and nitrobenzene taken from other model ecosystem studies (Lu and Metcalf 1974). For the limited number of compounds Included, the correlation between physical properties and biomagnification is excellent. The regression equation for log water solubility vs log E.M. (Figure 4) was: y *4.4806 -- 0.4732 X : n*9, -0.9677 Fig. 4. riot of log E.M. (ecological magnification) for fish vs. log water solubility (ppb). HONS 062163 Ingcd with 81 % oT the and 19% in the fecal Mflijtlc compounds by be a function of two iiity, i.c,, a larp.c lipid/ y enzymatic pioccsscs, 973). Ilamclink ct al. olublo compounds pioof simple partitionings ;U's and 1)1)1: from the i) in Figure A, and with use Die values for the extended using values tne taken from other number of compounds ntficalton is excellent, d) was: 577 i Degradation of Polychlorinated Biphenyls Compared with DDf: 163 The regression equation for log partition coefficient (Ihmsch's n) vs. log IZ.M. (Figure 5) was: ' y = -- 0.750-1 + 1.1587 X : n = 9, r = 0.9771 Thus for the organic compounds studied, the properties of water solubility and octnnol/watcr partition coefficient appear to provide a realistic estimate of the biological magnification found in living organisms. : * unlintn Millirw IlI .0 7.0 0.0 ter solubility (ppb). Fig. 5. Plot of log U.M. (ecological magnification) for fish vs. log octanol/walcr partition coefficient. . Acknowledgments This tcscaich was supported in patt by icseauh giants from the U. S. Department of Interior, Office of Water Resources Research through the University of Illinois Water Resources Center Project 11-050, Illinois; the National Science Foundation Grant Cl 39843X,.thc U. S. environmental Protection Agency Grant K8Q2022 and Grant R800736, and the Bureau of Veterinary Medicine, Food and Drug Administration, Contract FDA 72-116. HUNS 082264 164 R. 1,. Metcalf cl al. References Costs, J. R., R, L. Metcalf, and 1.1*. Kapoor: Metabolism of the nicthoxychlor isostere, dianisylncopcntnnc in mouse, insects, and a model ecosystem. Pesticide Uiochcnv Physiol. 4,201 (1974). Datta, P. R.: / vivo detoxication of /y/-DDT via p,/?f*DDE top,//-DDA in tats. Ind. Med. 39,190(1970). t ltomclink, J. L., R. C. Waybrant, and R. C. Rail* A proposal: exchange equilibria control the degree chloiinatcd hydrocarbons are biologically magnified in Icntic cnviiun- ments. Trans. Am. Fisheries Soc. 100,207 (1971). Hulzingcr, O., D. M. Nash, S. Safe, A. S. W. DcFtcitas, R. J. Noistiom, D. J. Wildish, and V. Zikkos: Polychlorinated biphenyls: metabolic behavior of pure isomers in pigeons, rats, and brook trout. Science 178,312 (1972). Kapoor, 1.1\, R. L. Metcalf, A. S. Mirvvc, J. R. Coats, and M. S. Khalsa: Structure activity correlations of biodegradability of DDT analogs. J. Agr. Food Chem. 21, 310 (1973). Kapoor, 1. P., R. L. Metcalf, A. S. Hirwc, Po-Yung Lu, J. R. Coats, and R. F. Nystrom: Comparative metabolism of DDT, methylchlor, and cthoxychlor in mouse, insects, and in a model ecosystem. J. Agr. Food Chem. 20,1 (1972).. Kapoor, 1. P., R. L. Metcalf, R. F. Nystrom, and G. K. Sangha: Comparative metabolism of nrethoxychlor, methylchlor, and DDT in mouse, insects and in a model ecosystem. J. Agr. Food Chem. 18,1145 (1970). Kettv, R O. F. 4 rtnrtrw\( nnir r\ 5uyske*. Determination of lflC r.d -'.l *U( biclogL*! MMiplva 'uj S^uwitigvi vu*nbu5iiuu ami liquid scintillation technique. Anal. Biochcm 2,267 (1961). Kemcr, I., W. Klein, and F. Koric: Photochemischc Reactionen von l.l-dichloro^-O?,/?- diclilorocthylenc) DDE. Tetraliedron 28, 1575 (1972). Lu, Po-Yung, and R. L. Metcalf: Degradation and environmental fate of radiolabeled benzene derivatives in a model aquatic ecosystem. Ms. in preparation. Maugh, T. H. II: DDT: An unrecognized source of polycliloiinaicd biphenyls. Science 180,578 (1973). Metcalf, R. L, G. M. Booth, C. K. Schulh, D. J. Hansen, and Po*Yung Lu: Uptake and fate of di`2-ethylhcxyl plithalatc in aquatic oiganisms and in a model ecosystem. Environ. Health Persp. Expert. Issue 4, 27 (1973b). Metcalf, R. L., I. P. Kapoor, Po-Yung Lu, C- K. Schulh, and P. Shennan: Model ecosystem studies of the environmental fate of six oig.modiloiinc pesticides. Environ. Health Persp. F.xpcri. Issue 4, 35 (1973a). Metcalf, R. L., G. K. Sangha, and 1. P. Kapoor: A laboratory model ecosystem. Environ. Sci.Techfiol. 5, 709 (1971). * Metcalf, R. L., Po-Yung Lu, and I. P. Kapoor: Environmental distribution and metabolic fate of key industrial pollutants and pesticides in a model ecosystem. Univ. 111. Water Resources Center,Kept. No. 69, Project B490 111. (1973). MONs 08^65 1 H.<| ** I` toxychfor isotfcre, Pesticide liiochcm. '-DDA In rats. Ind. J , ! ;t equilibria control I In Icntlc amiom >,P.J. Wildish, and af pure isomers in i: Structure Activity ad Chem, 21,310 end R. Ir. Nystrom: or In moose, insects, rUperaanlidveImn eatabmoolisdmel j , j ' j ! j Ij ,r aj.4 SU In (ton tecnmquc. Ainu. , ),l-dlchloro2(/>,/>- I j t ' I hie of radiolabeled niton. rd bl|dicny)t. Science Veenit l.w: Uptake and in e inodel ccoiyitcni. j , i . J P, Sltnmaii: Model mocldiiilnc prsllildci. let (coayitem. Environ. (button and metabolic I ecoiyitcm. Unlv. 111. U). - Degradinlon of Polychlorinated Diphenyls Compared with DDIi 165 Moilanen, K. W., and D. C. Crosby: Vapor-phase photodecomposition of/>,//-DDT and Its relatives. Abst. No. 27 (1973) 165th Meeting American Chemical Society. Ptakall, I). B., and 3. L. Lmccr: Polychlorinated biphenyls, anotitcr long-lire widespread chemical in the environment. Dioscicncc 20,958 (1970). nimmcr, J. R., U. I. Kiingclbiel, and B. E. Hummer: Photooxidation of DDT and DDE. Science 167,67 (1970). Risebrough, R. W., P. Kicchc, D. B. Pcakall, S. G. Herman, and M. N. Kirven: Poly chlorinated biphenyls in the global ecosystem. Nntuic 220,1098 (1968). Sodergren, A.: Transport, distribution, and degradation of chlorinated hydrocarbon residues in aquatic model ecosystems. Oikos 24,30 (1973). Wallnofcr, P. R., G. Engclhafdi, S. Safe, and D. Hulzingcr: Microbial hydroxylalion of 4-clilorobiphcnyl and 4,4'dichlorobiphcnyt. Chemosphcrc 2,69 (1973). Webb, R. G., and A. C. McCall: Identities of polychlorinated biphenyl isomers in Aroclois. J. Assoc. Offic. Agr. Chem. 55,746 (1972). Yoshimura,!!., and H. Yanimamoto: Metabolic studies on polychlorinated biphenyls III. Complete structure and acute toxicity of the metabolites of 2,4,3',4'-(etrachlorobiphcnyl. Chem. Pharm. Bull. (Japan) 21,2239 (1973). M.an4uscr.ipt recei.ved, March. 18, 1974; accepted May 14, 1974 j '' - w -- ' MUNS 08^66 I I