%0 Generic %D 2021 %T Exploring Personal Chemical Exposures of Structural Firefighters Using Silicone Dog-tags as Passive Samplers %A Emily M Bonner %A Carolyn M Poutasse %A Walker S Carlos Poston %A Sara A Jahnke %A Christopher K Haddock %A Lane G Tidwell %A Peter D Hoffman %A Kim A Anderson %X

Structural firefighters are exposed to many potentially hazardous chemicals while on the job. In a burning building, chemicals in furniture, building materials, and home goods can be volatilized in the high heat, and pyrogenic chemicals can be formed. Adverse health outcomes observed in firefighters, such as increased incidence of various cancers and cardiovascular disease, raise concerns about these occupational exposures. This study seeks to compare chemical exposures of firefighters when on- and off-duty using silicone dog-tags worn around the neck, as passive samplers. There were 57 firefighter participants selected from two-stations in the Kansas City Metropolitan area; on average, one received fewer than two calls per month (low call volume), and the other received more than 12 calls per month (high call volume). Each firefighter wore two separate dog-tags while on- and off-duty for a total of 30 24-hour shifts. The firefighters also filled out questionnaires, indicating the number of fire attacks they participated in while wearing the tags, as well as other demographic and lifestyle information that might inform exposures. The dog-tags were extracted and analyzed using GC-MS. This presentation will focus on results for two chemical classes, polychlorinated biphenyls (PCBs) and volatile organic chemicals (VOCs). Preliminary data show that 16 different firefighters were exposed to PCBs, 12 of which were from the high call volume station. Additionally, 12 different PCB congeners were detected. It is hypothesized that chemical concentrations in paired on-duty versus off-duty tags will be higher, and that the high versus low call volume station will have greater chemical concentrations. Other questions about concentration correlation to questionnaire data, PCB sources, and potential adverse health outcomes linked to the observed exposures will also be explored. Silicone passive samplers are a useful tool in gathering data on chemical exposures of firefighters because they can mimic dermal absorption of the bioavailable phase, a particularly concerning route of exposure for firefighters. They are also easy to use and maintain, allowing for this month-long exposure study. This application of passive sampling will help us better characterize the occupational exposures of firefighters when they are on- and off-duty, and how that is impacted by station call-volume.

%B SETAC North America 42nd Annual Meeting %8 11/2021 %G eng %0 Journal Article %J J Am Soc Mass Spectrom %D 2015 %T Electron Capture Dissociation of Sodium-Adducted Peptides on a Modified Quadrupole/Time-of-Flight Mass Spectrometer. %A Voinov, Valery G %A Peter D Hoffman %A Bennett, Samuel E %A Beckman, Joseph S %A Barofsky, Douglas F %K Amino Acid Sequence %K Electrons %K Equipment Design %K Mass Spectrometry %K Models, Molecular %K Peptides %K Sodium %X

Electron capture dissociation (ECD), which generally preserves the position of labile post-translational modifications, can be a powerful method for de novo sequencing of proteins and peptides. In this report, ECD product-ion mass spectra of singly and doubly sodiated, nonphosphorylated, and phosphorylated peptides are presented and compared with the ECD mass spectra of their protonated counterparts. ECD of doubly charged, singly sodiated peptides yielded essentially the same sequence information as was produced by the corresponding doubly protonated peptides. The presence of several sodium binding sites on the polypeptide backbone, however, resulted in more complicated spectra. This situation is aggravated by the zwitterionic equilibrium of the free acid peptide precursors. The product-ion spectra of doubly and triply charged peptides possessing two sodium ions were further complicated by the existence of isomers created by the differential distribution of sodium binding sites. Triply charged, phosphorylated precursors containing one sodium, wherein the sodium is attached exclusively to the PO4 group, were found to be as useful for sequence analysis as the fully protonated species. Although sodium adducts are generally minimized during sample preparation, it appears that they can nonetheless provide useful sequence information. Additionally, they enable straightforward identification of a peptide's charge state, even on low-resolution instruments. The experiments were carried out using a radio frequency-free electromagnetostatic cell retrofitted into the collision-induced dissociation (CID) section of a hybrid quadrupole/time-of-flight tandem mass spectrometer. Graphical Abstract ᅟ.

%B J Am Soc Mass Spectrom %V 26 %P 2096-104 %8 2015 Dec %G eng %N 12 %R 10.1007/s13361-015-1230-y %0 Journal Article %J Oecologia %D 2014 %T Elevational differences in trait response to UV-B radiation by long-toed salamander populations. %A Thurman, Lindsey L %A Garcia, Tiffany S %A Peter D Hoffman %K Altitude %K Animals %K Behavior, Animal %K Deoxyribodipyrimidine Photo-Lyase %K DNA Damage %K Ecosystem %K Female %K Oviposition %K Stress, Physiological %K Ultraviolet Rays %K Urodela %X

Amphibian species capable of optimizing trait response to environmental stressors may develop complex strategies for defending against rapid environmental change. Trait responses may differ between populations, particularly if stressor strength varies across spatial or temporal gradients. Ultraviolet-B (UV-B) radiation is one such stressor that poses a significant threat to amphibian species. We examined the ability of long-toed salamanders (Ambystoma macrodactylum) at high- and low-elevation breeding sites to cooperatively employ behavioral and physiological trait responses to mediate UV-B damage. We performed a microhabitat survey to examine differences in oviposition behavior and UV-B conditions among breeding populations at high- (n = 3; >1,500 m) and low-elevation (n = 3; <100 m) sites. We found significant differences in oviposition behavior across populations, with females at high-elevation sites selecting oviposition substrates in UV-B protected microhabitats. We also collected eggs (n = 633) from each of the breeding sites for analysis of photolyase activity, a photoreactivating enzyme that repairs UV-B damage to the DNA, using a photoproduct immunoassay. Our results revealed no significant differences in photolyase activity between long-toed salamander populations at high and low elevations. For high-elevation salamander populations, relatively low physiological repair capabilities in embryos appear to be buffered by extensive behavioral modifications to reduce UV-B exposure and standardize developmental temperatures. This study provides valuable insight into environmental stress responses via the assessment of multiple traits in allowing sensitive species to persist in rapidly changing landscapes.

%B Oecologia %V 175 %P 835-45 %8 2014 Jul %G eng %N 3 %R 10.1007/s00442-014-2957-z