Document QXdVYYry5J4eGdGbaEm1bbwo7

chance, we must suspect that the key References s>d Notes range was not delimited. All samples to their evolution is a dissipative mecha nism not present in the solar system today. It might have involved a viscous medium in the early solar nebula or the influence of a passing star. A study of evolutionary models with such alternate mechanisms might provide useful clues about conditions in the young solar system. R. J. Grf.enbero C. C. COUNSELMAN, III I. I. Shapiro Department of Earth and Planetary Sciences, Massachusetts Institute of Technology, Cambridge 02139 1. See. for example, F. Goldrekh, Mon. Hoik. Roy. Astron. Soc. 19$, 159 (1965). 2. A complete discussion is given by R. J. Oreenberg. theftit, Massachusetts Institute of Tech nology (September 1972). 3. D. Brouwer and G. Ctomence. Methods of CsUstlal Mechanics (Academic Press, New York, 1951), p. *92. 4. This qualitative tspeet of the stability for rela tively high values of et was described by Goldrelch (/) and by C. J. Cohen and E. C, Hubbard [Astrun. i. 99, 10 (1965)). 5. The time scale for the evolution of the TitanHyperion resonance presents certain problems; these are discussed in (2). 6. R. R. Allan, in Symposia Mmlemaiica (Istituto Nazlonale di Alta Matemailca, CitU UxUvertttaria, Rome, 1970), vol. 3, p. 75. Here the con junction loogkude librates about the average longitude o4 the satellites* ascending nodes os Saturn's equatorial plane, so the resonance involves the inclinations of both satellites. JO lime 1972 were collected with oblique plankton tows by using the National Academy of Sciences (NAS) reference net (0.5 m in diameter at the mouth; mesh size 33.1 /un) equipped with a flowmeter (J). The highest concentrations observed were in the Niantic Bay area with an average of about 1 spherule per cubic meter for 72 samples taken on six dates between February and May 1972. Concentra tions up to 14 m B were observed in this area. At other stations sampled in February to March 1972 the average concentrations were as follows: Long Island Sound (stations 22 to 27), 0.07 m~*; east of Block Island (stations 1 3 to 18), 0.03 m~ *; Great Salt Pond on Block Island and west to Long Island Polystyrene Spherules in Coastal Waters Sound (stations 19 to 21), 0.02 m~ *. Bacteria and polychlorinated bi Abstract. Polystyrene spherules averaging 0.5 millimetehin diameter (rpnge 0.1 phenyls (PCB's) are present nn j||rfaee<i to 2 millimeters) are abundant in the coastal waters of southern New England. Two of the plastic particles. Freshly collected types are present, a crystalline (clear) form and a white, opaque form with pig spherules from Niantic Bay were trans mentation resulting from a diene rubber. The spherules have bacteria on their ferred through four washings of sterile surfaces and contain polychlorinated biphenyls, apparently absorbed from ambient seawater and plated onto A-C seawater seawater, in a concentration of 5 parts per million. White,'opaque spherules are medium (4), where rod-shaped gram selectively consumed by 8 species of fish out of 14 species examined, and a chae- negative bacteria were observed after tognath. Ingestion of the plastic may lead to intestinal blockage in smaller fish. incubation. An extraction of the surface of the spherules from Niantic Bay with Polystyrene spherules are widespread sediments since polystyrene is of a great hexane showed that they contained in the coastal waters of southern New er density than seawater. PCB's (Aroclor 125^4) in a concentration England. We first observed spherical The spherules are present in coastal of 5 parts per million. Since PCB's are plastic particles in plankton tows in January 1971 while sampling to deter mine the effects of a nuclear power sta tion on the ecology of Niantic Bay waters from western Long Island Sound to Vineyard Sound (Table 1), and may be more widespread since their total not added in the manufacture of poly styrene (2), it is probable that the j source was ambient seawater. / (northeastern Long Island Sound). The panicles, although usually present in zooplankton samples throughout the Table 1. Sample location, date, volume filtered, and concentration of plastic spherules in coastal water. Stations 1 to 12 were in an area of about 10 km1; the averages and ranges of the spherule concentrations at these 12 stations are presented. year, were not investigated in detail until February 1972. The spherules are markedly different in size, shape, dis tribution, and chemical composition from the plastics on (he Sargasso Sea surface (/). Infrared spectrophotometry of the particles indicated that they were poly styrene plastic. Two types are present in seawater, in approximately equal proportions. One is a clear or crystal line polystyrene, and the other is a white, opaque form with pigmentation due to the presence of a diene rubber compound in the plastic, as indicated by infrared spectrophotometry and con firmed by a representative of the plastics industry (2). Both forms are virtually perfect spheres and average about 0.5 mm in diameter, ranging from 0.1 to 2 mm. They contain various sires and numbers of gaseous voids. Thus, they are found at the sea surface, in the water column, and presumably in the Station 1-12 1-12 1-12 1-12 1-12 J3 14 15 16 17 18 19 20 21 22 23 24 25 26 27 Location 41*1874, 72*10W 4i-i8'N, 72*iow 41*1874, 72'low 41*1874,72* 10W 41*1874, 72* 10W 41*3474,70*43W 41*3474, 70*43W 41*3074, 70*39W 41*3071,70*39W 41*2074,71"03W 41*13.574,71*18W 41*0974, 71*33W 41*1274, 71*44W 41*1274,72*00W 41*1074, 72"2W 41*0974,72* S6W 41*0874, 72*52W 41*1674, 72*01W 41*1774, 72*03W 41*1774, 71*59W Date (1972) Volume filtered (m*) Niantic Bay 1 February 17 February 16 March 7 April 25 May Buzzards Bay 9 March 9 March Vineyard Sound 10 March 10 March Rhode Island Sound 24 March 25 March Great Sait Pood 25 March Block Island Sound 25 March 25 March Long Island Sound 25 March 25 March 25 March 23 March 23 March 23 March 475 140 513 603 387 59 50 48 31 108 76 94 191 104 280 122 48 109 125 151 Spherules per cubic meter Avg. Range 0.75 2.58 0.79 0.13 0.61 0.03 0.02 0.02 0.00 0.10 0.00 0.04 OjOI 0.01 0.10 04)5 0.10 0.05 oxn 0.04 0.39-1.94 0.62-14.1 0.00-2.52 0.00-0.51 0.03-2.44 17 NOVEMBER 1072 0SW 032128 7*9 STLCOPCB4016090 Spherules arc consumed by fish in the Nianlic Day area; only the white, opaque form has been found ingested, which indicates selective feeding. Four teen species of fish, totaling 270 individ uals, were collected by oblique plank ton tows with the NAS not in the bay or at the cooling water intake of the Millstone Point nuclear power station, also on Niantic Bay. Of these, eight species contained spherules in their gut contents. The species, common name, and occurrence of plastic, of fish with spherules for which at least five individ uals were examined are: Myotocepha lus aenus, grubby, 4.2 percent; Pseudoplcuroni'ctrs americanus, winter floun der, 2.1 percent; Horens americanus, while perch, 33 percent; and Menidia menidia, silvcrsidcs, 33 percent (5). In addition, one chactognalh, Sagitta clcgatis, was collected on 12 July 1972; it was 20 mm long and had a spherule 0.6.mm in diameter in its intestine. The effects on fish of consuming the sphe rules themselves or the accompanying I1 l'CB's arc unknown; however, it is likcj ly that they can cause intestinal block age in sonic of the smaller fish. Winter flounder and grubby larvae, 5 nim in length, contained spherules 0.5 mm in diameter. The percentage consumption of plastics by some species of fish may be greater than observed here if in gestion of the spherules directly or in directly causes mortality through block age, thereby preventing sampling of these fish. The spherules appear identical 1o polystyrene plastic "suspension beads." These beads arc not usually marketed commercially (6), but arc molded into a pellet shape before being sold to plas tic fabricators. Thus, the source of the spherules is probably a manufacturer and may lie any of the many polyslyrcnc producers in southern New F.ngland. Although the situation may be confined to this area, the bead suspen sion process is widely employed for the manufacture of polystyrene, and con tamination of both marine and fresh waters and their sediments may occur in other areas as well. Edward J. Carpenter Susan J. Anderson, Georoe R. Harvey Hi i i n P. Miki.as. Bradford B. Peck Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543 References and Notes 1. i;, J. < nipcntrr and K. L, Smilli, Jr., Silrnie 175. 1240 (1972). 2. K. Bmjjfss, Dow Chemical Co., Midland, MU'Dipim, personal communication. 3. Recommended Procedure.t for Measuring the Productivity of Vimnkton Standing Stock and Related Oceanic Properties (National Academy of Sciences, Wa*hington, DC., 1969). 4. Vlho Manual (Dilco laboratories, Detroit, ed. 9. 1953). 5. The total number of flsb examined, average total length In centimeters, and standard de viation of the total length for fish containing spherules are: M. aenus, 47, 0.58, 0.12; P. aniericonus, 95, 0.46, 0.44; R. americanus, 12, 24.9, 3.98; M. menJdia, 9, 1.61, 1.89; Tauto- golabrus adspersus, 6, 9.1f, 1.81. Two herring, Clupeo harengus, each 4.2 cm; one pollack, PolJachlus vlrens, 3 cm; and one Rea robin, Prlonotls evalans, 32.7 cm, were collected; each contained a spherule. 6. R. Harding, Society of Plastics Industry, New York, personal communication. Polystyrene beads also have some limited usage as abaorbants for industrial water purification. 7. We thank R. Harding for his cooperation and for notifying all polystyrene manufacturers in the United States of the presence of p!:nic spherules In coastal waters. Gratitude Is also expressed to F. Doohan and S. Young (or allowing one of u (E.J.C.) to collect samples from the R.V. Verrll. We also appreciate the critical review of this manuscript by P. H. Wiebc, N. S. Fisher, J. H. rutile, V. Vrechnd. and R. S. Scheltema. Woods Hole Oceano graphic Institution Contribution 2V2G. 1 September 1972 Rous Sarcoma Virus Nucleotide Sequences in Cellular DNA: Measurement by RNA-DNA Hybridization Abstract. Kinetic analysis of the hybridization of 71S RNA from Prague strain of Rous sarcoma virus with an excess of DNA from virus induced sarcomas indi cated the presence of the majority of the viral genome sequences in cellular DNA with a very low average frequency per cell. About one-third of the viral sequences were at least partially complementary to DNA sequences with a higher average frequency on the order of 50 to J00 per ceil. Normal chick embryo DNA w<j.v distinctly different, but contained sequences at least partially homologous to some fraction of the viral RNA. The proposal by Temin (7) that RNA tumor viruses replicate through a DNA intermediate has been supported by an increasing body of indirect evi dence. The discovery of RNA-dependent DNA polymerase activity within tumor virus particles strengthened this "provirus" hypothesis. The direct detec tion of viral nucleotide sequences by annealing viral RNA with cellular DNA seems to be a reasonable ap proach for testing this idea. However, RNA-DNA hybridization studies have yielded conflicting results. Although most investigators have found viral complementary sequences in oellular DNA, some have found evidence for more complementary DNA in Yirustransformed cells (2, 3), while others report no significant differences between normal and virus-infected tissue (4-8). Technical problems may underly the varying conclusions since, in all eases, only a very small fraction of the viral RNA was detected in the RNA-DNA hybrids. Furthermore, the conditions under which the hybridization reactions were carried out would not be expected to reveal small numbers of complete viral genomes per cell genome, particu larly if multiple copies of DNA in the cell complementary to a small fraction of the viral RNA were present. The rate of hybridization reported in these previous studies suggests the presence of such repetitive virus-related DNA (d). A method has been described for detecting full complements of RNA in cellular DNA and for obtaining rea sonable estimates of frequency even when very low (5-7). The method is based upon hybridization in the pres ence of an excess of DNA large enough for the kinetics of RNA-DNA inter action to be determined by the relative number of complementary sequences in the DNA. By this approach, it is pos sible to detect most, if not all, of the base sequences of Rous sarcoma virus in the DNA of virus-induced sarcomas, and to demonstrate major differences with DNA sequences complementary to viral RNA in normal embryos. Prague strain of Rous sarcoma virus subgroup C (Pr RSV-C) was selected as Ihc source of viral RNA because it is a helper-independent avian sarcoma virus that replicates efficiently in cell culture and produces rapidly growing sarcomas in newborn chicks (8). Chick embryo fibroblast cultures transformed by Pr RSV were incubated in medium 199 (prepared without unlabeled nu cleosides and made 5 percent in fetal calf scrum) with 100 pc of pHluridinc, pH]cytidinc, and [3H]adenosine per milliliter (22, 26, and 9 c/mmole, re spectively). Culture fluid was harvested after 24 hours, and labeled virus par ticles were purified from culture fluids by banding in sucrose gradients (20 to 60 percent). Viral RNA was extracted by the sodium dodccyl sulfate-phenol technique (9). The 715 viral genome, separated from low-molecular-weight nucleic acids by sedimentation in su crose gradients (5 to 20 percent) in 0.01 M tris buffer containing 0.00 \M 750 ~ience. vo!.. ns 0SW 032129 STLCOPCB4016091