Polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD) are common flame retardants in polymers and textiles. Recognition of the persistent, bioaccumulative, and toxic properties of PBDEs has prompted reductions in their use. In contrast, HBCD has received less scrutiny. The U.S has historically been a dominant BFR consumer. However, the few publications on HBCD in wildlife here suggest modest levels compared to Asian and European studies. In contrast, the HBCD concentrations we detected in U.S. fish are among the highest reported in the world. The temporal trends observed suggest that HBCD use may have risen, and that of Penta-BDE declined, following the 2004 termination of its U.S. manufacture. For example, Hyco River carp collected in 1999–2002 exhibited a mean ∑HBCD (sum of α-, β- and γ-HBCD) concentration of only 13 ng/g (lipid weight basis), but was 4640 ng/g in fish collected in 2006–2007. In contrast, the mean ∑PBDE level in these same fish decreased from 40,700 ng/g in 1999–2002 ...
Da Chen; Mark J. La Guardia; Drew R. Luellen; Ellen Harvey; T. Matteson Mainor; Robert C. Hale
The two enantiomers of 2-(2-hydroxybiphenyl-4-yl)propanoic acid ((S)- and (R)-BPOH) have been selected as probes for human serum albumin (HSA). Photophysical characterization in the absence of protein led to emission maxima, singlet energies, quantum yields, and fluorescence lifetime values ... more
The photodissociation of H2O in its B band is a prototype for nonadiabatic reaction dynamics. In addition to dissociation via the adiabatic pathway to the OH(Ã2Σ+) + H fragments, it also produces the OH(X̃2Π) + H fragments through two nonadiabatic pathways: the B̃ → X̃ transition via two co ... more
Due to the widespread occurrence in the environment and potential risk toward organisms of fluoroquinolones (FQs), it is of importance to develop high efficient methods for assessing their occurrence and environmental risk. A monoclonal antibody (Mab) with broad cross-reactivity to FQs was ... more
Rohm and Haas Powder Coatings is delighted to announce that its Reading, Pennsylvania, facility is the first site in the world to receive the RCMS® Site Certification awarded by the American Chemical Council (ACC).
When Raj Gupta, Chairman and CEO of Rohm and Haas Company, became Chairman ... more