title: Headspace solid-phase microextraction with gas chromatography-mass spectrometry determination of naphthalene in the composite food samples from the 2011 Canadian total diet study in Ottawa.
abstract: A method based on isotope dilution headspace solid-phase microextraction, followed by gas chromatography and mass spectrometry, was developed for the determination of naphthalene in foods. Optimum method sensitivity was achieved by the addition of NaCl in water at saturation and with  the sample solution incubated at 30°C for 15 min. The method had good repeatability, with relative standard deviations of 3.5 and 1.5% at 5 and 30 ng/ml, respectively. This method was used to determine naphthalene in 159 food composite samples collected from the 2011 Canadian Total Diet  Study. Naphthalene was detected in 93 (58.9%) food composite samples, mostly in products of meat and cereal, fast food, and miscellaneous foods. Among the 93 samples, only 51 (54.8%) samples were found to contain naphthalene at levels above 1 ng/g, with a maximum of 35 ng/g found in the herbs  and spices composite sample. Method detection limits, estimated for each one of the food composite samples by using the lower-abundance ionm/z 127, varied considerably because of the matrix effect, ranging from as low as 0.0022 ng/g for water to as high as 16 ng/g for fatty sample,  with an average of 1.6 ng/g.
authors.affiliation: Food Research Division, Bureau of Chemical Safety, Health Canada, AL: 2203D, Ottawa, Ontario, Canada K1A 0K9. Xu-Liang.Cao@hc-sc.gc.ca
authors.forename: Xu-Liang
authors.initials: XL
authors.lastname: Cao
authors.forename: Tara
authors.initials: T
authors.lastname: Hierlihy
authors.forename: Svetlana
authors.initials: S
authors.lastname: Popovic
authors.forename: Bob
authors.initials: B
authors.lastname: Dabeka
mesh_terms: D003257:Consumer Product Safety; D005504:Food Analysis / Q000379:methods; D005506:Food Contamination / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D009281:Naphthalenes / Q000032:analysis*; D009864:Ontario; D052617:Solid Phase Microextraction / Q000379:methods*; D013696:Temperature; D013997:Time Factors
chemical_list: D009281:Naphthalenes; C031721:naphthalene