NEWS OF THE WEEK
NEWSCOM
MOMENTUM FOR CHEMICAL CONTROL TSCA: Senate panel examines toxic substances act, 13 states call for reform
E Jackson
FFORTS TO UPDATE the federal law governing chemical manufacture gained momentum last week as the Senate held a hearing on the issue and a coalition of states called for a rewrite of the Toxic Substances Control Act (TSCA). At the Senate Environment & Public Works Committee hearing, Sen. Frank R. Lautenberg (D-N.J.) said he would introduce a TSCA reform soon. The House has held hearings on revamping the chemical control law but has no legislation to do so as yet (C&EN, Nov. 23, page 8). Lautenberg said his bill “will require companies to prove that their products are safe before they end up in a store, in our homes, or in our bodies.” He added, “We already regulate pesticides and pharmaceuticals this way.” In 2005 and 2008, Lautenberg sponsored legislation to recast TSCA as the Kid-Safe Chemicals Act. But the measure failed in the face of opposition from chemical manufacturers and the Bush Administration. But this year, things have changed. Now, major seg-
CUSTOMIZED NANOPARTICLES CATALYSIS: Method endows platinum
with benefits of solid- and solution-phase catalysts
NAT. CHEM.
C
ATALYSIS WITH metal nanoparticles has been
rendered more convenient and effective thanks to a new catalyst preparation method devised by a group in California. These dendrimer- and polymerencapsulated metal nanoparticles can catalyze, with high efficiency, reactions that until now have been accessible exclusively via solution-phase chemistry. The new work highlights a novel synthesis strategy for customizing the function of solidphase catalysts that, compared with solution-phase catalysts, are more easily separated and recycled from solvents and dissolved products (Nat. Chem., DOI: IN A BIND A new method encapsulates platinum 10.1038/nchem.468). nanocatalysts in dendrimers (top) or polymers A central thrust (bottom) and supports them on porous silica. in catalysis research WWW.CEN-ONLINE.ORG
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ments of the chemical industry, led by the American Chemistry Council, are backing modernization of the 33-year-old TSCA. In addition, the Obama Administration has ranked revising the law among its top environmental priorities. Lautenberg’s fellow senators on the committee have taken note of these shifts. As the hearing began, many expressed interest in revamping TSCA. The hearing included testimony from EPA Administrator Lisa P. Jackson about that law. But in their questioning of her, senators paid scant attention to TSCA. All queries from Republicans and some from Democrats focused on e-mails between prominent climate scientists that were stolen and posted on the Internet late last month. The e-mails suggest the scientists worked to wield tighter control over the peer review process of some climate journals and the Intergovernmental Panel on Climate Change. Jackson maintained that the emails do not affect the scientific consensus that climate change is happening and that humans are the cause. Separate from the hearing, a coalition of 13 states joined the call to reform TSCA. California, Connecticut, Illinois, Maine, Maryland, Massachusetts, Michigan, New Hampshire, New Jersey, New York, Oregon, Vermont, and Washington want the law revised in part to promote the development and use of safer products and chemicals.—CHERYL HOGUE
focuses on combining advantages of solution-phase (homogeneous) and solid-phase (heterogeneous) catalysts. A common approach is to immobilize homogeneous catalysts on a solid support so they can be separated easily and inexpensively from reaction mixtures. Typically, such immobilized catalysts are limited to mediating the same reactions as their mobile counterparts. Rather than following that strategy, chemists Cole A. Witham, F. Dean Toste, Gabor A. Somorjai, and coworkers at the University of California, Berkeley, have tailored the properties of platinum nanoparticles to drive reactions never before catalyzed by solids. Specifically, the team made the particles electrophilic by treating them with iodosobenzene dichloride. Then they encapsulated them in a polyamidoamine dendrimer or in polyvinylpyrrolidone and dispersed the composites on porous silica to render them thermally stable and to prevent them from aggregating. Ring-closing test reactions show that in some cases the new catalysts are even more active than soluble platinum catalysts. For example, the encapsulated catalysts convert a phenylethynyl phenol to the corresponding benzofuran in roughly 100% yield—slightly higher than solution-phase platinum compounds. David Milstein, a professor of chemistry at Weizmann Institute, in Rehovot, Israel, notes this “groundbreaking” strategy for tuning nanoparticle properties holds promise for discovering novel catalytic reactions beyond those offered by traditional heterogeneous systems or soluble metal complexes.—MITCH JACOBY
DECEMBER 7, 2009
