The QuEChERS Approach with GC-TOFMS and GCxGC-TOFMS for PAHs in Oil Contaminated Seafood

Hi Everyone:

I’ve had several requests for my 2010 Florida Pesticide Residue Workshop poster, The QuEChERS Approach with GC-TOFMS and GCxGC-TOFMS for PAHs in Oil Contaminated Seafood, so I am going to post it here:  FPRW P-39 PAHs Seafood Cochran

In summary, it represents preliminary attempts to adapt the QuEChERS extraction and cleanup approach to relatively low-fat seafood samples for PAH analysis.  As you know from previous posts and the news, the topic of PAHs in seafood is significant because of the recent Gulf oil spill.  I also used QuEChERS and GCxGC-TOFMS to analyze a NIST Standard Reference Material freeze-dried mussel tissue for PAHs.  (I actually have more recent data on this that I will be posting soon.)

Comments are welcome.  Enjoy.

Love Canal: Summer Vacation.

On a recent trip through Niagara Falls, New York, I forced the family to stop off and visit the remnants of what is now known as Love Canal – sidewalks disappear into brush and an occasional home can be seen through the overgrown vegetation. Our 5-year-old twins were full of questions.  “Why are we driving around in the woods?” When I graduated from college I wanted to “save the environment” and was not really sure what that meant. My first job was in an environmental lab where the hours were long and the work was hectic. Drinking water samples were coming in at an alarming pace with what is known as 7-day-hold-times. That is they must be analyzed within 7 days of sampling. Many of the samples arrived with only a day or two left on them. Late arriving samples could ruin weekend plans and added a high degree of stress to an already crazy schedule. One day I mentioned my frustration to Gary Stidsen about my failure to achieve my dream of “saving the environment.” He described the work they had done over the years on the Love Canal samples and told the story of Love Canal from an analytical chemist point of view. He put human faces to all of those nameless samples that filled our refrigerators. I have been drawn to Love Canal ever since because it validates our work analyzing drinking water, waste water and toxic waste samples and those tests keep our families safe (and yes those labs are saving the environment).

Guides for the analysis of organic wastes:

Guide to Preparing and Analyzing Chlorinated Pesticides

Our Most Recent Technical Articles

Home located on the outer circle, these homes were evacuated by President Carter but some refused to leave.

 

Home on 101st Street, in 2008 it was the only home in the evacuated zone where children live.

Looking from 102nd Street towards the former location of the 99th St. School. Remediation facility is located at the canal.

Love Canal: Horrors & Heroes.

In 1977, Niagara Gazette reporter Michael Brown wrote articles detailing the 20,000 tons of toxic waste buried under the 99th Street Elementary School. Lois Gibbs, a 101st Street resident of Love Canal, took these articles to her brother-in-law, a biology professor. He confirmed her worse fears that these chemicals can affect the central nervous system. Her 5-year-old son, who attended the elementary school, had been suffering from epilepsy, asthma, liver problems, and a urinary tract disorder. All of these problems had started since moving to Love Canal. Gibbs began working with Dr. Beverly Paigen of Roswell Memorial Institute where they evaluated 245 houses that were not in the ring closest to the waste. In those families there were 34 miscarriages, 18 birth defects, 19 nervous breakdowns, 10 epilepsy cases and high rates of hyperactivity and suicide. Further studies completed in 2008 found that rates of congenital malformations were twice that expected compared to the external standard population. The horrors for some as a result of exposure continue to this day.

            Michael Brown & Lois Gibbs efforts resulted in daily front-line media coverage. This was a turning point for environmental awareness and helped shape the methods we use in the lab today. The analysis done in environmental labs has a huge impact in protecting the public and ultimately saving lives. This one goes out to the heroes: Michael Brown, Lois Gibbs & Environmental Labs across the county.

More information on Love Canal can be found on page 6 of  Optimizing the Analysis of Volatile Organic Compounds.

Links to the analysis of other compounds found there and around the country: Dioxin, PCBs, and SVOAs.

GCxGC-TOFMS of Riser Pipe Oil from BP Gulf Oil Spill

I recently analyzed an oil sample collected by an ROV from the riser pipe at the BP Gulf oil spill site using GCxGC-TOFMS, a powerful multidimensional technique capable of characterizing complex samples that defy one-dimensional GC-MS.

The GCxGC column setup was a 30m x 0.25mm x 0.25µm Rxi-17Sil MS in the first dimension with a 1.2m x 0.15mm x 0.15µm Rxi-1ms in the second dimension.  This arrangement puts the highly aromatic compounds (e.g. PAHs) at the bottom of the GCxGC chromatogram (contour plot; see first figure) while the aliphatics are retained by the Rxi-1ms in the second dimension, eluting away from the aromatics.  Given that PAHs, which are shown eluting in the box on the first figure, are considered the “toxic” compounds in crude oil, this is an efficient GCxGC arrangement for their interference-free determination.  Having a full mass range TOFMS allows spectral fingerprinting of the resolved components, including PAHs. 

As pointed out in literature (see below) and by experts in the field (e.g. Ed Overton, Professor Emeritus at LSU), the crude oil associated with this spill is relatively “light” in nature as regards PAHs, with mainly naphthalene, fluorene, phenanthrene, anthracene, and most importantly, their alkyl homologs (especially C1, C2, and C3 as seen in the second figure).  The reason I say most importantly is that many laboratories gearing up for seafood analysis as a result of the oil spill will focus only on the unalkylated (is that a word?) PAHs, likely because that is where most of the published toxicity information lies.  Do the alkyl PAHs, which form the bulk of the PAH contribution of this oil, have equivalent toxicity?  I don’t know, but I do wonder if they should be included in Gulf oil spill monitoring schemes, whether the analysis is for environmental or food samples.

D. J. Hallett, F.I. Onuska, and M.E. Comba, Marine Environmental Research 8 (1983) 73-85, Aliphatic and Polyaromatic Components of Weathered and Unweathered Southern Louisiana Crude Oil

Jonathan Keim becomes Jonathan Chime at the Florida Pesticide Residue Workshop

Restek Sample Preparation Product Manager, Jonathan Keim, was assigned one of the most important jobs at the 47th Florida Pesticide Residue Workshop, that of xylophone artiste’ to alert conferees who are visiting exhibitors and posters at coffee break to return to the starting Technical Session.  He got the hang of it quickly and his “Smoke on the Water” rendition was appreciated by the older rockers at the workshop…

International Morning Yesterday at FPRW

The Florida Pesticide Residue Workshop went international yesterday morning as seen from the program below.  For those of you who are working hard on pesticide and vet drug residue analysis, these presentations gave some good context on why we are doing these analyses.  They make a difference for governments and chemical companies and farmers and consumers.  Given that food export/import is so important, from financial and food safety perspectives, understanding the broad issues for all impacted parties is mandatory.  This FPRW session provided that for its audience.  

Hopefully all the authors will allow posting of their presentations at FLworkshop.com  soon, so check there occasionally.

8:30 – 10:30 am Oral Session – Global Chemical Contaminant Conflicts … and Resolutions
André de Kok and Charles Yang, co-chairs
8:30 – 9:00 Recent Developments in European Pesticide Registration and Impact on Global Trade -
O-10 Monika Bross; BASF, Limburgerhof, Germany
9:00 – 9:30 Challenges for Governmental Pesticide Laboratories in Brazil/Latin America -
O-11 Ionara Pizzutti; Federal University of Santa Maria, Brazil
9:30 – 10:00 Pre-Harvest Monitoring and Management of Pesticide Residues in India -
O-12 Kaushik Banerjee; National Research Centre for Grapes, Pune, India
10:00 – 10:30 Monitoring of Pesticide Residues in Export Products of Plant Origin in China –
O-13 Jianhua Wang – Shandong Exit & Entry Inspection and Quarantine Bureau, Qingdao, China

Restek Colleagues and QuEChERS at the Florida Pesticide Residue Workshop

Jonathan Keim, Michelle Misselwitz, and Julie Kowalski manning the Restek booth at the 47th Florida Pesticide Residue Workshop and showing off the new Restek Q-sep QuEChERS extraction salts packets.

Great Day of QuEChERS at FPRW

We were lucky enough at the Florida Pesticide Residue Workshop today to see the inventors of QuEChERS, Steve Lehotay of USDA and Michelangelo Anastassiades of CVUA-Stuttgart, talk about methods (and approaches; there is a difference!) in a session after the main FPRW program.  Interesting points were raised about method modifications, including solvents used, choice of dSPE sorbents, to customize or not customize, and the possibility of a unified method (currently there are three methods, the original with MgSO4 and NaCl, and the AOAC with acetic acid and sodium acetate buffering system, and the citrate salts buffering system of EN 15662).  There may be a collaborative study conducted by AOAC on a unified method.  Stay tuned!

Michelle Misselwitz Does Dietary Supplements at Florida Pesticide Residue Workshop

No, I’m not revealing any of Michelle’s personal habits here. But I do want to say what a great job she did talking about QuEChERS, cartridge SPE, and GCxGC-TOFMS for the analysis of pesticides in dietary supplements at the Restek vendor seminar at FPRW last night (Sunday). Her talk was visually stimulating, great graphics, and was very well received by over 60 attendees!

Many thanks to Jonathan Keim and Julie Kowalski also, who assisted with the workshop and let everyone know about the new Restek QuEChERS extraction salt packets.

P.S. The flavor tripping party was wild: Chardonnay turned to Reisling (Ask Andre de Kok!)

Restek at the Florida Pesticide Residue Workshop Starting July 18

 

Join me and my colleagues Michelle Misselwitz, Julie Kowalski, and Jonathan Keim at the Florida Pesticide Residue Workshop next week for some fun science.  In addition to the offerings below, we’ll also be handing out some sweet treats (hint: one of my co-workers has the same initials) at our exhibition booth. 

Restek Seminar

 

Sunday, July 18, 7:00-8:00 p.m. in
Banyan/Citrus Room in Jacaranda Hall
Presented by: Michelle Misselwitz, Environmental
Innovations Chemist, Restek

Enhancing That Certain Part of the GC Anatomy with QuEChERS and Cartridge SPE Cleanup for Pesticides in Dietary Supplements

 

Restek Posters

 

P-39 The QuEChERS Approach with GC-TOFMS and GCxGC-TOFMS for PAHs in Oil Contaminated Seafood
Jack Cochran; Restek Corporation
 
P-45 Large Volume Injection for Gas Chromatography Using a Commercially Available Unmodified Splitless Injector
Jack Cochran; Restek Corporation
 
P-46 Large Volume Injection on Split/Splitless Inlets “The Pauper’s Upgrade”
Lee Miller, Raymond Allum; Florida Dept. of Agriculture and Consumer Services and Jack Cochran; Restek Corporation
 
P-47 QuEChERS Approach with GCxGC-ECD and GC-TOFMS for the Analysis of Pesticides in Dried Ginseng
Michelle Misselwitz, Jack Cochran, Julie Kowalski, Rick Lake and Jason Thomas; Restek Corporation
 
P-48 Analysis of Polycyclic Aromatic Hydrocarbons in Infant Formula using the QuEChERS Approach Combined with Both Liquid and Gas Chromatography
Julie Kowalski, Michelle Misselwitz and Jack Cochran; Restek Corporation
 
 
 
FPRW Special Session on the Oil Spill
Sunday, July 18, 2:00 p.m. in Blue Heron
Led by: Dr. Ed Overton, Professor Emeritus at LSU
and Jack Cochran, Restek Corporation
Special Session On Organic Analyses in Support of the Recent Gulf Coast Oil Spill.