The monitoring of pharmaceuticals and personal care products (PPCPs) has focused on the distribution in rivers and small lakes, but data regarding their occurrence and effects in large lake systems, such as the Great Lakes, are sparse. Wastewater treatment processes have not been optimized to remove influent PPCPs and are a major source of PPCPs in the environment. Furthermore, PPCPs are not currently regulated in wastewater effluent. In this experiment we evaluated the concentration, and corresponding risk, of PPCPs from a wastewater effluent source at varying distances in Lake Michigan. Fifty-four PPCPs and hormones were assessed on six different dates over a two-year period from surface water and sediment samples up to 3.2 km from a wastewater treatment plant and at two sites within a harbor. Thirty-two PPCPs were detected in Lake Michigan and 30 were detected in the sediment, with numerous PPCPs being detected up to 3.2 km away from the shoreline. The most frequently detected PPCPs in Lake Michigan were metformin, caffeine, sulfamethoxazole, and triclosan. To determine the ecological risk, the maximum measured environmental concentrations were compared to the predicted no-effect concentration and 14 PPCPs were found to be of medium or high ecological risk. The environmental risk of PPCPs in large lake systems, such as the Great Lakes, has been questioned due to high dilution; however, the concentrations found in this study, and their corresponding risk quotient, indicate a significant threat by PPCPs to the health of the Great Lakes, particularly near shore organisms.

Although the field of microfluidics has made significant progress in bringing new tools to address biological questions, the accessibility and adoption of microfluidics within the life sciences are still limited. Open microfluidic systems have the potential to lower the barriers to adoption, but the absence of robust design rules has hindered their use. Here, we present an open microfluidic platform, suspended microfluidics, that uses surface tension to fill and maintain a fluid in microscale structures devoid of a ceiling and floor. We developed a simple and ubiquitous model predicting fluid flow in suspended microfluidic systems and show that it encompasses many known capillary phenomena. Suspended microfluidics was used to create arrays of collagen membranes, mico Dots (μDots), in a horizontal plane separating two fluidic chambers, demonstrating a transwell platform able to discern collective or individual cellular invasion. Further, we demonstrated that μDots can also be used as a simple multiplexed 3D cellular growth platform. Using the μDot array, we probed the combined effects of soluble factors and matrix components, finding that laminin mitigates the growth suppression properties of the matrix metalloproteinase inhibitor GM6001. Based on the same fluidic principles, we created a suspended microfluidic metabolite extraction platform using a multilayer biphasic system that leverages the accessibility of open microchannels to retrieve steroids and other metabolites readily from cell culture. Suspended microfluidics brings the high degree of fluidic control and unique functionality of closed microfluidics into the highly accessible and robust platform of open microfluidics.high throughput metabolomics | multiplexed cell culture | spontaneous capillary flow | passive biphasic systems | arrayed migration platform

Organosulfates have been proposed as contributors to aerosol growth and have been detected in both chamber and atmospheric aerosol samples. We present a simple method for the synthesis of quantitative analytical standards of two small hydroxycarboxylic acid-derived organosulfates, glycolic and lactic acid sulfate. Additionally, we discuss the stability of hydroxycarboxylic acid-derived organosulfates and their previously proposed sulfate hemiacetal isomers in commonly used solvents for filter extraction. The hydroxycarboxylic acid-derived organosulfates were found to be stable under acidic conditions comparable to those found in ambient aerosol. By using synthesized standards, quantitative organosulfate concentrations were measured from ambient particulate matter (PM(2.5)) collected in urban locations in the United States, Mexico City, and Pakistan. Lactic acid sulfate and glycolic acid sulfate concentrations ranged 0.4-3.8 ng/m(3) and 1.9-11.3 ng/m(3), respectively. We propose that glycolic acid sulfate represents an important tracer for atmospheric processes that form organosulfates in ambient particulate matter.

The transformation of the sulfonamide antimicrobial sulfamethazine (SMZ) by a synthetic analogue of the birnessite-family mineral vernadite (δ-MnO(2)) was studied. The observed pseudo-first-order reaction constants (k(obs)) decreased as the pH increased from 4.0 to 5.6, consistent with the decline in δ-MnO(2) reduction potential with increasing pH. Molecular oxygen accelerated SMZ transformation by δ-MnO(2) and influenced the transformation product distribution. Increases in the Na(+) concentration produced declines in k(obs). Transformation products identified by tandem mass spectrometry and the use of (13)C-labeled SMZ included an azo dimer self-coupling product and SO(2) extrusion products. Product analysis and density functional theory calculations are consistent with surface precursor complex formation followed by single-electron transfer from SMZ to δ-MnO(2) to produce SMZ radical species. Sulfamethazine radicals undergo further transformation by at least two pathways: radical-radical self-coupling or a Smiles-type rearrangement with O addition and then extrusion of SO(3). Experiments conducted in H(2)(18)O or in the presence of (18)O(2)(aq) demonstrated that oxygen both from the lattice of as-synthesized δ-MnO(2) and initially present as dissolved oxygen reacted with SMZ. The study results suggest that the oxic state and pH of soil and sediment environments can be expected to influence manganese oxide-mediated transformation of sulfonamide antimicrobials.

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