Flow cytometry (FC) was used to determine effects of tetrabromobisphenol A (TBBPA) on the green alga Chlorella pyrenoidosa (C. pyrenoidosa) by evaluating esterase activity, membrane integrity, concentrations of intracellular reactive oxygen species (ROS) and chlorophyll a (Chl-a) auto-fluorescence. TBBPA can inhibit esterase activity. Esterase activity was inversely proportional with TBBPA with a 24 h EC(50) value of 3.13 mg TBBPA/L. After 48 h of exposure to TBBPA intracellular ROS was significantly greater than in the unexposed cells. TBBPA inhibited Chl-a fluorescence after 168 h. Concentrations of ROS were directly proportional to both magnitude and duration of exposure and was inversely proportional to cellular Chl-a. FC was useful as an integrated, ecologically relevant, measure of a functional response of the algae. The possible action pathway of TBBPA in C. pyrenoidosa is that TBBPA can cause toxic effects on esterase activity. As concentrations and exposure time increased, TBBPA change the ROS level in the internal. The role of anti-oxidative action is marked and significant at the duration of 48 h exposure, compared to the control. This suggested there was a redox cycle. TBBPA changes physiological status of cells, further decreased Chl-a fluorescence indicating inhibition.

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Nonthermal plasma (NTP)-based treatments of volatile organic compounds (VOCs) have potential for effective environmental remediation. Theory and experiment that consider the basic science pertaining to discharge events have helped improve NTP remediation outcomes. If direct information on early post-discharge chemical intermediates were also available, it would likely lead to additional improvement in NTP remediation outcomes. To this point, however, experiments yielding direct information on post-NTP VOC intermediates have been limited. An approach using supersonic expansion molecular beam methods offers general promise for detection of post-discharge VOC intermediates. To illustrate the potential utility of these methods, we present mass spectra showing the growth of early products formed when pulsed corona discharges were carried out on toluene in He and then in He with added O2. Good general detection of neutral post-discharge species was obtained using 800 nm 150 fs photoionization pulses.

We have employed 800 nm 150 fs laser pulses to carry out photoionization (PI) time-of-flight mass spectrometric detection of intermediates following corona discharges on aromatic molecules (alkylbenzenes and pyridine) in He, stabilized by subsequent supersonic gas expansions. Observed product peaks appear to be at least roughly in proportion to actual number densities; PI induced fragmentation of parent ions appears not to be excessive. Consequently, 800 nm fs PI should be useful for general product analysis applications in plasma chemistry. For most alkylbenzenes subjected to corona discharges in rare gas, the overall trends in product chemistry are similar in many respects to observed flame and pyrolysis chemistry in rare gases for the same species. Following discharge, as in those other cases, H deficient carbon radical fragments initially produced react in turn to form larger aromatic species. However, compared with flame/pyrolysis, discharge produced a larger number of fragment species, which can lead to a wider and somewhat different range of higher mass aromatic products. Co-addition of even a small component of O 2 to the discharge mixes has a potent effect in inhibiting formation of higher mass aromatic products in alkylbenzenes.