Cyclic volatile methyl siloxanes (cVMS) are anthropogenic chemicals present in a range of consumer personal care products such as antiperspirants and lotions. They are highly volatile, and readily released to the atmosphere by personal care product use. Generally unreactive, they are found in high concentrations in indoor environments, and transported long distances in the atmosphere. A major removal pathway for these silicon-containing gases is reaction with the OH radical, which has been recently shown to yield secondary Si-containing aerosol compounds in addition to the gas phase products. Despite the significance of the atmospheric fate of these compounds, much of the previous work has focused on the aquatic fate, and almost exclusively on the parent compounds. The oxidation products and potential aerosol species have received much less attention, with almost no ambient measurements or experimental physical property data. This work investigates cVMS with a focus on providing much needed information on potential loadings of the oxidation products, their distribution, and particle phase properties using an atmospheric model and laboratory experiments. Specifically, cVMS was added to the Community Multiscale Air Quality (CMAQ) model; expected concentrations, spatial distribution, and seasonal trends were quantified; cVMS secondary aerosols generated and physical properties characterized; and secondary aerosol parameters for atmospheric modeling developed. The CMAQ model code was modified to update the chemical mechanism with cVMS, develop emissions, boundary, and deposition parameters to simulate four separate seasons at a spatial resolution of 36 km over North America. Typical model concentrations showed parent compounds were highly dependent on population density as cities had monthly averaged peak decamethylcyclopentasiloxane (D5) concentrations up to 432 ng m−3. Peak oxidized D5 concentrations were significantly less, up to 9 ng m−3, and were located downwind of major urban areas. Model results were compared to available measurements and previous simulation results. Parent compound concentrations in urban locations were sensitive to transport factors, while parent compounds in rural areas and oxidized product concentrations were influenced by large-scale seasonal variability in OH. Secondary aerosols were formed by reacting cVMS gas in an oxidation flow reactor. The particles were characterized for concentration, size, aerosol yield, morphology, energy-dispersive spectroscopy (EDS) individual particle chemical composition, hygroscopicity (cloud condensation nuclei formation potential), and volatility. Aerosol concentrations were 68 – 220 µg m-3 with aerosol mass fractions (i.e. yields) of 0.22-0.50. Aerosol yield was sensitive to chamber OH, indicating an interplay between oxidation conditions and the concentration of lower volatility species. The D5 oxidation products were non-volatile, with only the smallest particles (10 nm) exhibiting more than 4% of diameter decrease upon heating to 190°C temperature. The D5 oxidation aerosols were relatively non-hygroscopic, with average hygroscopicity kappa of ~0.01. Experimental data was analyzed to develop secondary aerosol parameters for the CMAQ model. Chamber yield data was fit to a two-product Odum volatility model with yield values of 0.14 and 0.82, corresponding to saturation concentrations of 0.95 and 484 µg m-3, respectively. The recommended enthalpy of vaporization is 18 kJ mol-1 based on other modeled secondary organic aerosol. Recommended molecular weights for the D5 low volatility Odum, high volatility Odum, and non-volatile oligomerization species are 588, 373, and 733 g mol-1 corresponding to OH substituted ring-opened, monomer, and dimer species, respectively. This work provides simulations of expected concentrations, spatial patterns, and seasonal influence of the parent and oxidized cVMS species to extend beyond the few parent cVMS measurements and nonexistent oxidation product measurements. The modeling work serves as an important tool to guide future field measurements especially important for the confirmation of particle phase oxidation products. Extensive aerosol characterization measurements provide much needed physical property data important for future modeling, risk, and exposure studies.

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Background: China's rapidly growing beauty consumer market has led to environmental deterioration and Chinese citizens are aware of this important issue, however, despite positive pro-environmental attitudes, consumers are reluctant to buy green products. This issue is known as the attitude-behavior gap, and existing research lacks information on how this gap operates in the Chinese beauty market. Purpose: The purpose of this study is to use the ACB (Affective, Cognitive, Behavioral) Attitude Model to explore how the attitude-behavior gap works in the Chinese beauty market, specifically, the attitudes of Chinese consumers and how they influence behavior. Method: This study was an exploratory qualitative study in which 30 Chinese participants were interviewed in 3 focus groups consisting of 10 participants each. For the purpose of this study, participants' attitudes toward beauty and personal care products were investigated. Conclusion: The empirical findings show that green knowledge is considered the most important factor in the attitude-behavior gap, as consumption habits and patterns hinder purchase behavior. Second, is health consciousness, where purchase behavior is hindered by the skepticism of product attributes and insufficient information. Third, self-image, as overpackaging makes consumers think that it is detrimental to their image of green consumption. Finally, social influence is the least important factor, as Chinese people are collectivistic and purchasing behavior is more likely to be influenced by surroundings. By prioritizing these four factors, beauty companies and marketers can understand what is preventing Chinese consumers from purchasing beauty and personal care products, and then have the appropriate marketing strategies to respond.

BACKGROUND:The widespread utilization of organic compounds in modern society and their dispersion through wastewater have resulted in extensive contamination of source and drinking waters. The vast majority of these compounds are not regulated in wastewater outfalls or in drinking water while trace amounts of certain compounds can impact aquatic wildlife. Hence it is prudent to monitor these contaminants in water sources until sufficient toxicological data relevant to humans becomes available. A method was developed for the analysis of 36 trace organic contaminants (TOrCs) including pharmaceuticals, pesticides, steroid hormones (androgens, progestins, and glucocorticoids), personal care products and polyfluorinated compounds (PFCs) using a single solid phase extraction (SPE) technique with ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). The method was applied to a variety of water matrices to demonstrate method performance and reliability.RESULTS:UHPLC-MS/MS in both positive and negative electrospray ionization (ESI) modes was employed to achieve optimum sensitivity while reducing sample analysis time (<20min) compared with previously published methods. The detection limits for most compounds was lower than 1.0 picogram on the column while reporting limits in water ranged from 0.1 to 15ng/L based on the extraction of a 1L sample and concentration to 1mL. Recoveries in ultrapure water for most compounds were between 90-110%, while recoveries in surface water and wastewater were in the range of 39-121% and 38-141% respectively. The analytical method was successfully applied to analyze samples across several different water matrices including wastewater, groundwater, surface water and drinking water at different stages of the treatment. Among several compounds detected in wastewater, sucralose and TCPP showed the highest concentrations.CONCLUSION:The proposed method is sensitive, rapid and robust / hence it can be used to analyze a large variety of trace organic compounds in different water matrixes.

The Pecan Creek Waste Reclamation Plant in Denton, Texas, an activated sludge WWTP, was sampled monthly for ten months to determine seasonal and site variation in concentrations of triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol), an antibacterial additive. SNK separation after the highly significant ANOVA on ranked data were: summer = fall > winter = spring and influent > downstream = effluent = wetland inflow > wetland outflow (a=0.05). After the plant converted to ultraviolet disinfection, measurements were made before and after the UV basin to determine if significant amounts of triclosan were converted to dioxin. Percent loss at each of the treatment steps was determined. Concentrations of triclosan in the downstream site were below the published NOEC for the most sensitive species.