Lab Matters Summer 2018 | Page 48

APHL 2018 Annual Meeting Poster Abstracts

Environmental Health activities , including annual environmental laboratory conferences , laboratory standardization and method development workgroups , various trainings and communications to connect environmental laboratories . The second cooperative agreement was awarded in 2011 and concluded November 30 , 2017 . During this time , APHL continued to play a leadership role by serving as an environmental laboratory sector liaison , organizing conferences , task forces and work group meetings , disseminating and sharing information and providing technical assistance through training opportunities . This poster will explore the quantitative and qualitative measures of this nearly twelve year partnership between US EPA and APHL , as well as its ultimate effect on strengthening environmental laboratories .

Presenter : Sarah Wright , MS , Association of Public Health Laboratories , Silver Spring , MD , Phone : 240.485.2730 , Email : sarah . wright @ aphl . org

Gas Chromatography / Tandem Mass Spectrometry Analysis of Volatile Organic Compounds

K . Castor , T . Kim and M . Koltunov , California Department of Toxic Substances Control , Pasadena , CA

Our public health is greatly affected by our environment . Depending on where we live and work , we could be exposed to a variety of environmental contaminants ; from the air we breathe , to the water we drink , to the soil on which we build our houses . At The Environmental Chemistry Laboratory in Pasadena , our mission statement includes striving to be leaders in analytical and environmental chemistry to protect California ’ s people and environment from toxic harm . One class of compounds that we are interested in from a public health aspect is volatile organic compounds ( VOCs ). VOCs are a group of compounds with low boiling points ( below 200 ° C ), low to medium water solubility and low molecular weights . They are anthropogenic ( man-made ) contaminants found in different matrices such as soil , waste water and indoor air . Due to their prevalence and toxic nature , the Public Health Goal ( PGH ) in drinking water for various VOCs are in the very low µ g / L and pg / L range , which emphasizes the need to enable detection of these compounds at very low levels . We have developed a GC / triple quadrupole mass spectrometric ( GC / MS-QQQ ) analysis for VOC quantitation using a dynamic multiple reaction monitoring method ( dMRM ). Samples are introduced using a purge and trap system . Our dMRM method allows for detection down to 0.5 µ g / L with great selectivity and high sensitivity for desired compounds . Additionally , we can analyze 62 compounds in a single run , allowing for reduced analysis time .

Presenter : Katherine Castor , PhD , California Department of Toxic Substances Control , Pasadena , CA , Phone : 626.304.2692 , Email : katherine . castor @ dtsc . ca . gov

Gas Chromatography / Tandem Mass Spectrometry Analysis of Pesticides

K . Castor , J . Men and M . Koltunov , California Department of Toxic Substances Control , Pasadena , CA

Our public health is greatly affected by our environment . Depending on where we live and work , we could be exposed to a variety of environmental contaminants ; from the air we breathe , to the water we drink , to the soil on which we build our houses . At The Environmental Chemistry Laboratory in Pasadena , our mission statement includes striving to be leaders in analytical and environmental chemistry to protect California ’ s people and environment from toxic harm . One class of compounds that we are interested in from a public health aspect is pesticides . Organophosphorus and organochlorine pesticides are neurotoxic and are the active ingredients in many insecticides used in agricultural , residential and commercial landscape settings . After their use , pesticides can remain in the soil . Parathion , an organophosphorus compound , has a low oral LD50 of 3 – 8 mg / kg , which emphasizes the need to enable detection of these compounds at very low mg / kg or µ g / kg levels . Traditional analysis relies on separation and detection of pesticides using gas chromatography coupled to a flame photometric detector ( GC / FPD ) or electron capture detector ( GC / ECD ). These techniques detect the signals from either the phosphorus or chlorine atoms and rely on a second column confirmation , resulting in a longer analysis time and a higher detection limit (> 50 µ g / kg ). We have developed a GC / triple quadrupole mass spectrometric ( GC / MS-QQQ ) analysis for multiple compounds of interest that uses a dynamic multiple reaction monitoring ( dMRM ) method to enable specific mass detection of each compound , thus eliminating the second column confirmation . In addition , the dMRM method allows for detection down to 1 - 2.5 µ g / kg by minimizing interference from other compounds . The quantitation is based on specific mass and fragmentation pattern of each analyte of interest and is a very powerful method to analyze soil contaminants .

Presenter : Katherine Castor , PhD , California Department of Toxic Substances Control , Pasadena , CA , Phone : 626.304.2692 , Email : katherine . castor @ dtsc . ca . gov

Evaluating Associations Between PFAS Detected in Drinking Water and Human Serum in Northern California

S . Crispo Smith , M . Petreas and J . S . Park , California Department of Toxic Substances Control , Pasadena , CA

Per- and polyfluoroalkyl substances ( PFASs ) are a large class of anthropogenic and persistent chemicals , some of which bioaccumulate and are associated with testicular and kidney cancer , high cholesterol , ulcerative colitis , thyroid disease and preeclampsia . Public concern regarding the ubiquity and potential toxicity of legacy and next-generation PFASs in drinking water has led to increased regulatory pressure requiring more sensitive and selective analytical methods . Our previous study suggests drinking water could be a significant exposure route for PFASs in the general population ( 1 ). To evaluate any association between drinking water and serum PFAS concentrations , here we apply newly developed analytical methods to quantify PFAS in human serum and tap water collected from San Francisco Bay and Sacramento locations in Northern California . Using 0.25 mL of serum and 250 mL of water sample , the analyses were performed by using liquid chromatography ( Nexera UFLC system , Shimadzu ) coupled to a triple-quadrupole tandem mass spectrometer ( SCIEX QTRAP 5500 MS / MS system ). In both matrices , we were able to confidently measure 29 PFASs , including 10 out of the 12 analytes listed in EPA method 537 : eight perfluoroalkyl carboxylic acids ( PFCAs ), six telomer acids ( TAs ), four perfluoroalkyl sulfonates ( PFASs ), four polyfluorinated phosphate esters ( PAPs ), three perfluororoctanesulfonamides ( FOSAs ), two telomer sulfonates ( TSs ), one perfluoroalkylphosphinate ( PFPi ) and one perfluoroalkyl phosphonic acid ( PFAPA ). Our drinking water method has detection limits sufficiently sensitive to comply with