The panel was convened by the Na tional Toxicology Program's (NTP) Center for the Evaluation of Risks to Hu man Reproduction, and is examining re productive—but not cancer—risks posed by seven phthalate esters used as PVC plasticizers. In 1983, NTP conclud ed from animal studies that DEHP would be "reasonably anticipated to be a human carcinogen." Since then, most U.S. toy makers have stopped using DEHP, but some foreign manufacturers still use it in squeeze toys. The NTP panel determined from sev eral studies that high doses of DINP (150,000 to 300,000 ug per kg of body weight per day) given to pregnant rats cause reduced body weight and increased liver weight in the offspring. The Con sumer Product Safety Commission calcu lates that infants receive a maximum DINP exposure of 0.69 to 94.3 ug per kg of body weight per day by mouthing toys. So the doses causing adverse effects in rats are about three orders of magnitude great er than estimated human exposures. The conclusions for DEHP are not so sanguine. Doses of 3,000 to 250,000 \ig per kg per day cause testicular patholo gy in rodents. The greatest human ex posures to DEHP occur during medical procedures such as dialysis and blood transfusions. Adult hemodialysis with PVC equipment provides 140 μg per kg per day of DEHP, but neonatal transfu sions using PVC bags and tubing pro vide an average exposure of 1,700 \ig per kg per day. So neonatal exposure to DEHP can approach the range that causes adverse effects in lab animals. Raymond M. David, chairman of the toxicology research task group of the Chemical Manufacturers Association's Phthalate Esters Panel, cites two studies that he claims show DEHP is not a prob lem. In one study, animals treated with DEHP leached from PVC bags exhibited only minute changes observed by elec tron microscopy. In the other study, high levels of DEHP (2.5 g per kg per day) giv en to marmosets caused no adverse changes. Still, David says complete reso lution of the issue requires a study that evaluates effects on reproduction and de velopment across multiple generations. Two such studies are under way and are expected to be finished in a year or so. The Food & Drug Administration may soon cast some light on this issue. Its risk assessment of DEHP in medical devices was scheduled for completion just after C&EN went to press. Bette Hileman
Cleaner vehicles, gas to be required by EPA Smog in air and sulfur in gasoline will be reduced under a Clean Air Act regula tion issued just before Christmas by President Bill Clinton. The rule, for the first time, specifically couples automak ers and oil refiners by requiring cuts in nitrogen oxides (NOx) tailpipe emis sions of more than 77% and reductions in the sulfur content of gasoline by 90%. The new standards will be phased in over the next decade, with the first re quirements hitting in 2004. Clinton and the Environmental Pro tection Agency note that NOx is a pre cursor of ground-level ozone, while sul fur clogs catalytic converters that cap ture engine pollutants. The regulation also requires for the first time that popular sport-utility vehi cles (SUVs) and light trucks be includ ed with passenger cars in meeting na tional pollution standards. SUVs had been exempted under provisions creat ed for work vehicles. They account for some 50% of new vehicle sales. The new NOx standard is 0.07 g per mile, 77% less than today's standard for cars and 95% less than current emis
sions from the biggest SUVs. The stan dard allows manufacturers to use fleet averages to meet standards early on, but by 2009 all vehicles are to comply. For fuels, sulfur will be reduced to 30 ppm—about one-tenth of today's lev el—starting in 2005. EPAs regulation allows oil refiners to average sulfur lev els among different operations, but sets a cap that declines with time. It also pro vides special implementation delays for small refiners and refineries in Alaska and Rocky Mountain states. As a result, the full reductions, like the auto stan dard, aren't expected until around 2009. EPA estimates that the cost of the emissions reduction will be $100 per passenger vehicle and $200 per SUV, and that gas prices will rise by 2 cents per gal. Automakers and refiners say costs will be two or three times more. Overall, the program will cost the nation $5.3 billion, EPA says, and will result in health and environmental benefits of $25 billion. Clinton stressed children when mak ing the announcement at a Washington, D.C., elementary school, saying the rule will annually avoid 260,000 childhood asthma attacks and 173,000 childhood respiratory cases. JeffJohnson
King Midas' funeral featured stew and mixed drinks Mourners at the funeral feast for King Midas may have indulged in a spicy meal of lentils and barbecued lamb or goat and a mixture of wine, beer, and mead prior to sealing what is believed to be his tomb. Senior research scientist Patrick E. McGovern, an archaeological chemist at the University of Pennsylva nia Museum of Archaeology & Anthro pology in Philadelphia, and colleagues base these conclusions on their recent chemical analysis of residues found in vessels in the tomb [Nature, 402, 8 6 3 (1999)]. The researchers detected such ''fingerprint*' compounds as triacylgrycerols, cholesterol, saturated acids, tartaric acid, calcium oxalate, and beeswax. Mi das was the legendary king whose touch, a reward from the god Dionysus, was re puted to turn every object—including food—into gold, nearly leading him to die of starvation. Contemporaneous Assyrian records from about 700 B.C. indicate that he may have ruled the Phrygian kingdom, which had its capital in 7|P^ _ Gordion, now in present-day Turkey and the site of the tomb. First uncovered in 1957, the tomb was found to contain the skeleton of a man aged 60 to 65 as well as hundreds of bronze and pottery serving vessels and drinking bowls, including a ram's-head bucket Sophie Wilkinson JANUARY 3,2000 C&EN
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