experiments are radically different from those encountered in use of plastic blood bags in some impor­tant respects." Baxter contends that Rubin's method of dosing the rats— injecting them with emulsified DEHP—isn't encountered in trans­fusions, and that the emulsifier used alone can cause lung damage. Also, the firm points out, particulate DEHP found in Rubin's dose form, but not in transfusions, can cause more severe lung lesions. •

Guidelines issued for genetic research The year-long pause that apparent­ly has taken place in certain areas of genetic manipulation research may be at an end. Guidelines for conducting new research in the field of recombinant DNA now have been issued.

The guidelines constitute the re­port of the International Conference on Recombinant DNA Molecules, held last February in Asilomar, Calif. (C&EN, March 10, page 19). That meeting was organized by the Committee on Recombinant DNA Molecules, a group of concerned scientists headed by Stanford Uni­versity biochemistry professor Paul Berg. The committee, in concert with the National Research Council, had in June 1974 called for a volun­tary suspension of certain experi­ments, pending a study of their im­plications.

New techniques enable scientists to combine selected genetic infor­mation from very different orga­nisms to create a new organism. The concern of scientists in the field is that unknown but potential bio­hazards might arise as a result of such work.

At the same time, the work holds promise of great benefits. There is every reason to believe, the report states, that the new techniques will have significant practical utility in the future.

Meanwhile, the guidelines, repre­senting the consensus of the Asilo­mar conference, focus on two prin­ciples for dealing with potential risks: that containment be an essen­tial consideration in experimental design, and that the effectiveness of the containment match, as closely as possible, the estimated risk. The ways in which potential biohazards and different levels of containment are matched may vary from time to time, the report says, particularly as containment technology im­proves.

The most significant way to limit

the spread of recombinant DNA's, the report notes, is through use of biological barriers. These can in­volve either bacterial hosts unable to survive in natural environments or nontransmissible vectors, such as plasmids, bacteriophages, or other viruses, able to grow only in speci­fied hosts.

Noting that no classification can anticipate all situations, the report groups experiments into four cate­gories in making specific recom­mendations on containment pro­cedures: minimal, low, moderate, and high risk. Minimal risk, for ex­ample, includes those experiments in which biohazards may be assessed accurately and are ex­pected to be minimal. High risk in­cludes experiments in which the potential for ecological disruption or pathogenicity of the modified organism could be severe and there­by pose a serious biohazard to lab­oratory personnel or the public. •

Coke, Pepsi choose plastic bottles One of the plastics industry's most important marketing goals may fi­nally be in hand. Last week, the re­tail plastic carbonated beverage bottle emerged from years of test marketing into full-scale commer­cialization.

The two largest carbonated drink makers, Coca-Cola and Pepsi, both committed themselves to plastic retail bottles this year or next. Coca-Cola's new 32-oz plastic bottle using Monsanto's Lopac nitrile resin goes on sale immediately in Provi­dence, R.I. Pepsi says it will intro­duce a polyester bottle in 1976.

For chemical companies, these

Pepsi will use polyester bottles

developments mean victory for two of the leading resins contending for use in plastic bottles during the past decade. Monsanto has been work­ing on Lopac for at least as long. The company will be supplying finished bottles to Coca-Cola from three plants. One is currently in the start­up stage at South Windsor, Conn. Two others are being built at Havre de Grace outside Baltimore and Park Forest South outside Chicago. Monsanto produces the basic Lopac resin in Springfield, Mass.

A Monsanto spokesman says that there likely will be no problem sup­plying enough resin or bottles this year and next. Although there is no exclusive legal arrangement with Coca-Cola, Monsanto's production is effectively allocated to Coca-Cola for the present.

Coca-Cola's 32-oz plastic bottle in Providence will replace the glass bottle. The Atlanta-based beverage king is making the move after test marketing the new package in Providence and New Bedford, Mass., in 1970 and 1971.

Consumer acceptance in these tests added to physical advantages Coca-Cola found for plastic bottles. Donald R. Keough, president of Coca-Cola USA, told the press in New York City last week that he sees six of these advantages for nitrile-resin bottles over glass. First, the plastic bottle when filled weighs 25% less than a filled glass bottle. The plastic bottle also enables 15% more storage capacity. The new bottle reduces breakage, does not affect beverage taste, lends itself to recycling, and adapts to conven­tional disposal methods such as in­cineration.

On the recycling point, Coca-Cola is working on a returnable version of the new bottle. In the meantime, Monsanto plans a recycling cam­paign in the Providence area. Through a mobile collection net­work and existing recycling centers, Monsanto will offer 12.5 cents per lb for bottles returned by customers.

Environmental pluses also are involved in Pepsi's move to poly­ester bottles. From its headquarters in Purchase, N.Y., Pepsi said last week that environmental safety combines with other advantages to make polyester an even better choice than nitrile resin to replace glass. After testing both resin types, Pepsi notes that polyester resin takes less energy to produce than does nitrile and has higher impact strength. Pepsi also says that poly­ester does not require coloring to enhance consumer acceptability. Coca-Cola's new bottle has a green tint. •

6 C&EN June 9, 1975