Ethylene imports slated for Texas Tight supplies have prompted two U.S. petroleum companies to build facilities for importing large quantities of ethylene on the U.S. Gulf Coast. To be ready by the end of this year, the facilities are being developed jointly by Chevron Chemical and Exxon Chemical on the Houston Ship Channel. This is the first effort to import large volumes of ethylene by ship since the 1970s. The new facilities will be added to an existing liquefied petroleum gas terminal, known as the Warrengas Dock and owned by Warren Petroleum, a division of Chevron USA. A new terminal, pipeline connections to ethylene storage caverns at Mont Belvieu, Tex., and various facilities for storage, quality control, and distribution of ethylene will be included in the system. The ethylene import system will be a cost-effective way to improve the companies' supply flexibility during times of demand peaks and supply disruptions, says Kenneth N. Robertson, a vice president for Exxon Chemical. And George T. Scott, a vice president for Chevron Chemical, points out that with the tight ethylene supply situation, conventional exchanges of ethylene with nearby producers (to maintain a supply for customers during plant
enzymes that cleave DNA in specific locations. The pieces are then sepshutdowns for maintenance) have arated by gel electrophoresis. The become increasingly difficult to unique restriction fragment length polymorphisms (RFLPs)—that is, the ensure. There are many potential sources variations in the sites of attack of for imported ethylene. For exam- the restriction enzymes—of each inple, Exxon Chemical owns or has dividual are visualized through the interest in steam crackers in five use of a variety of radioactive probes. "DNA typing is the most significountries in addition to its U.S. plants. Ethylene, shipped as a liq- cant advance for forensics in this uid in tankers that also are used for century," says John W. Hicks, deppropane, will be regasified before uty assistant director of the Federal entering the pipeline system for eth- Bureau of Investigation's laboratoylene along the Gulf Coast. Indus- ry division. "It offers the potential try sources suggest the system ca- for a very powerful tool in linking pacity will initially be several hun- suspects to crimes." The FBI's own DNA typing lab is dred million lb per year. Expansion scheduled to open in October. About will follow as demand requires. During the past 12 months, de- the same time, the FBI will begin mand for ethylene has increased sig- training forensic scientists from state nificantly, spurred by export de- and local crime labs in the techmand for ethylene polymers, ethyl- nique. At the moment, none of the ene dichloride, vinyl chloride, and some 300 government-supported polyvinyl chloride. As a result, steam labs in the U.S. is running DNA crackers are being pushed to the profiles, Hicks says. All the analylimits of capacity. In the spring and ses are being carried out by Lifeso far this summer, plant problems codes and two other private firms, have caused unexpected shutdowns Cellmark Diagnostics of Germanof several units for varying periods, town, Md., and Forensics Sciences reducing potential output by a few Associates, a subsidiary of Cetus hundred million pounds. The de- Corp. in Emeryville, Calif. mand pressure on ethylene is exTo date, DNA profiles have been pected to push the price at the end used in court as evidence in seven of July to 31 cents per lb, up from states besides Virginia. At the moabout 14 cents per lb in July 1987. ment, the test's admissibility is being Bruce Greek determined on a case-by-case basis by the presiding judges. Attorney Fahey predicts, however, that DNA fingerprinting will rapidly become accepted throughout the criminal The technique is commonly re- justice system once an appeals court ferred to as "DNA fingerprinting," has ruled on the technique. Pamela Zurer a graphic term that underscores its utility in making identifications. The test depends on delineating those regions of DNA that vary among individuals. "Functional genes—those that code for enzymes, hormones, etc.— don't vary from person to person," Chemical company earnings for the says Karen B. Wexler of Lifecodes second quarter look strong, continCorp., the Valhalla, N.Y., firm that uing the trend for the past year. did the DNA typing in the Spencer The improved earnings have yet to case. But such genes only account be translated into higher prices for for about 5% of human DNA. "The chemical stocks, but Wall Street anrest is 'garbage DNA,' which varies alysts are actively recommending enormously from person to person," those stocks to their customers. she says. Earnings reports received so far To perform the analysis, a DNA from 11 companies show results in sample (only micrograms are needed) keeping with earlier expectations for is cut into fragments by restriction a strong second quarter. Five of
Death penalty imposed based on DNA profile A Virginia man has been found guilty of rape and murder and sentenced to die in the electric chair on the basis of DNA profiling, a forensic test that is rapidly gaining credence among law enforcement officials. The case is the first in which capital punishment has been imposed when DNA analysis was the key evidence linking the accused to the crime, the prosecuting attorney, Helen F. Fahey, believes. "The DNA typing was absolutely essential/' says Fahey, Virginia Commonwealth's Attorney. DNA from blood samples from the convicted man, Timothy W. Spencer, exactly matched DNA from semen stains found on the victim's clothing. "He could not have been convicted without this evidence," Fahey says.
Chemical earnings soar in second quarter
July 25, 1988 C&EN
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