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We investigated the performance of attenuated total reflectance-Fourier-transform infrared (ATR-FTIR) spectroscopy to rapidly identify intentional additives in a variety of items commonly handled by consumers and workers. We investigated ortho-phthalate esters, specific alternative plasticizers, and flame retardants in food contact materials and consumer products. We also investigated bisphenol A (BPA) and bisphenol S (BPS) developers in thermal paper purchase receipts. Applications include regulatory compliance screening and product deformulation. We compared FTIR results with mass spectrometry measurements. Samples were analyzed either intact or after a simple liquid-phase extraction using small amounts of nonhalogenated solvents. These methods greatly reduced the time and expense of identifying intentionally added phthalates and other plasticizers compared with more sensitive methods. Similarly, BPA and BPS were readily identified in receipts and organophosphorus flame retardants were identified in child car seats. In some samples, FTIR detected novel or unexpected additives not detected by conventional targeted methods. These approaches are useful for screening diverse product samples for intentional additives with a relatively portable instrument while generating very low volumes of spent solvent., Introduction The Ecology Center of Ann Arbor, Michigan, tests consumer products, publishes reports, and uses the data to engage with product manufacturers, brands, and retailers to eliminate chemical hazards and [...]

Abstract: Problem statement: Heavy metals constitute one of the most hazardous substances that could be accumulated in biota. Fish populations exploited by man often live in coastal area environments that contain high levels of heavy metals, coming from human activities such as industrial and agricultural wastes. A problem to deal when using fishes as biomonitors of heavy metals is the relationship existing between metal concentration and several intrinsic factors of the fish such as organism size, genetic composition and age of fish. Approach: Concentration of Zn, Cu and Pb were determined in eight commercially valuable fish species, Selaroides leptolepis, Euthynnus affinis, Parastromateus niger, Lutjanius malabaricus, Epinephelus sexfasciatus, Rastrelliger kanagurta, Nemipterus japonicus and Megalaspis cordyla from Pahang coastal water. The concentration was measured by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The study focuses on the level of Zn, Cu and Pb in order to assess the environmental pollution by using fishes as an indicator. Results: Concentrations of the heavy metals in examined fish species ranged as follow: Zn 19.27 g [mu]g [g.sup.-1] dry weight; Cu 2.88 p[mu]g [g.sup.-1] dry weight and Pb 0.26 [mu]g [g.sup.-1] dry weight, respectively. The concentrations of Zn, Cu and Pb were found to follow the order: stomach [greater than] muscle [greater than] gills. Significant correlations were found between fish weight and heavy metals concentration in the fish organs. Conclusion: The estimated values of all metals in muscles of fish in this study were below the established values. Therefore, it can be concluded that the fish from Pahang coastal water are comparatively clean and do not constitute a risk for human health., Key words: Pahang coastal water, Zn, Cu, Pb, ICP-MS INTRODUCTION Fish are the major part of human diet and it is not surprising that numerous studies have been carried out [...]

Laser-induced breakdown spectrometry (LIBS) has been used to detect atomic and molecular species in various environments. LIBS has the capability to be used as a continuous-emission monitor to monitor toxic-metal concentrations in stack emissions. Recently a mobile LIBS system was calibrated in our laboratory and tested as a multimetal continuous-emission monitor during a joint U.S. Department of Energy-Environmental Protection Agency (EPA) test. LIBS measurements were performed with three sets of metal concentrations at the EPA Rotary Kiln Incinerator Simulator. The LIBS system successfully measured concentrations of Cr, Pb, Cd, and Be in near real time in this test. Real-time LIBS data were averaged and compared with data obtained from an EPA reference method that was conducted concurrently with LIBS. The details of the LIBS calibration and results of these LIBS measurements are described.

An isotope dilution cold vapor inductively coupled plasma mass spectrometry (ID-CV-ICPMS) method featuring gaseous introduction of mercury via tin chloride reduction has been developed and applied to the quantification and certification of mercury in various NIST standard reference materials: SRM 966 Toxic Metals in Bovine Blood (30 ng [multiplied by] [mL.sup.-1]); SRM 1641d Mercury in Water (1.6 [micro]g [multiplied by] [mL.sup.-1]); and SRM 1946 Lake Superior Fish Tissue (436 ng [multiplied by] [g.sup.-1]). Complementary mercury data were generated for SRMs and NIST quality control standards using cold vapor atomic absorption spectroscopy (CVAAS). Certification results for the determination of mercury in SRM 1641d using two independent methods (ID-CV-ICPMS and CVAAS) showed a degree of agreement of 0.3% between the methods. Gaseous introduction of mercury into the ICPMS resulted in a single isotope sensitivity of 2 x [10.sup.6] counts [multiplied by] [s.sup.-1]/ng [multiplied by] [g.sup.-1] for [sup.201]Hg and significantly reduced the memory and washout effects traditionally encountered in solution nebulization ICPMS. Figures of merit for isotope ratio accuracy and precision were evaluated at dwell times of 10, 20, 40, 80, and 160 ms using SRM 3133 Mercury Spectrometric Solution. The optimum dwell time of 80 ms yielded a measured [sup.201]Hg/[sup.202]Hg isotope ratio within 0.13% of the theoretical natural value and a measurement precision of 0.34%, on the basis of three replicate injections of SRM 3133.

There are many instances where samples of potentially hazardous soils need to be acquired in such a way as to minimize the risk of injury to personnel. For example, sampling [...]

There has been a growing opposition to the use of animals in toxicology testing. Efforts have been made to shift away from larger animals to smaller ones, and toward more humane experimental conditions. There are two major reasons for trying to find alternatives to animal testing: humanitarian goals, and finding more reliable and accurate techniques, by which to predict possible adverse human health effects. The field of non-animal testing is in its early stages. At present, it is necessary to employ animals in some test situations, since protecting human health and welfare is the ultimate objective.