AOAC 133rd Annual Meeting - Final Program

Poster Abstracts | Tuesday

biomass reference materials are not certified for inorganic constituents. There has been an on-going debate as to whether biomass fuels are a carbon neutral energy source as well as a renewable energy source. Factors to consider when accounting for the contribution of carbon to greenhouse gas emission are the amounts of carbon released during each step of the process in the use of biomass materials; material production, transport of fuel, and biomass equipment operations. These two biomass SRMs were produced to help support environmental impact assessments; SRM 2790, composed of ground wood pellet fuel, and SRM 2791, composed of ground softwood bedding pellets, are value assigned for ash and 29 and 31 elements, respectively. Presenter: Laura Wood, U.S. National Institute of Standards and Technology, Gaithersburg, MD, USA, Email: laura.wood@nist.gov P-T-002 Alison Wakeham , Mologic, Bedfordshire, United Kingdom; Andrew Wheeler , Mologic, Hollis, ME, USA Development of Simple, Rapid, and Cost Effective In-Field Tests to Monitor and Predict Risk of Airborne Inoculum and Infection Events Worldwide, crop diseases are a major problem for producers with significant economic losses incurred. It has been estimated that an average of 20–30% of crop yield is lost annually from the field, even in crops where pesticides and cultivars with improved genetic resistance to pests and diseases are used. These losses can be greatly reduced by disease management practices steered by accurate and early diagnosis of patho- gen presence. Unfortunately, methods commonly adopted for the isolation and diagnosis of many pathogens are slow and normally, only deployed after disease symptoms have become apparent. For effective control and improved efficacy of product, early diagnosis of disease is essential. Yet, the ability to quickly diagnose common crop pathogens does not exist. Therefore simple, yet accurate, diagnostic tools for growers should be developed. By combining air sampling technology with cost effective and easy to use lateral flow immunoassays, we report the development and application of field-side tests to predict risk of airborne disease transmission events of crop pathogens in protected edible and field cropping systems. Information derived from these field-side tests (low, moderate, and high inoculum risk) is interfaced with weather driven models and has enabled producers to reduce and target control measures more effec- tively and with greater efficacy. The study was funded by the UK Agriculture Horticulture Development Board in collaboration with Mologic LTD. Presenter: Alison Wakeham, Mologic, Bedfordshire, MK44 2YA, United Kingdom, Email: alison.wakeham@mologic.co.uk P-T-003 Kari Organtini , Kenneth Rosnack , Waters Corp., Milford, MA, USA; Eimear McCall , Waters Corp., Wilmslow, United Kingdom Determination of Legacy and Emerging Perfluoroalkyl Substances Water Samples Using LC-MS/MS Perfluoroalkyl substances (PFAS) are common persistent environ- mental contaminants used in the production of many consumer

products. They are used as surfactants and for nonstick, stain, and water resistance coatings and in firefighting foams. Global use of these compounds over decades has led to their release into the environment. PFAS are classified as persistent organic pollutants. Currently, PFOS and PFOA are included in many drinking water health advisories in the United States (e.g., 70 ppt [ng/L]). In Europe, the Water Framework Directive and Drinking Water Directive have set minimum quality standards of PFOS and PFOA, which range from the ppb to sub-ppt levels. Such regulations have driven the need for highly sensitive analytical measurements to detect PFAS. Sample preparation, such as described in the ISO 25101 method, is typically applied for enrichment of PFAS in water samples. The scope of the ISO 25101 procedure has been expanded to cover approximately 40 legacy and emerging PFAS compounds, including GenX, using a weak anion exchange SPE cartridge. The method was assessed using surface, ground, influent and effluent water. The modified method was found to be robust in all types of matrices tested, with detection limits in the low to sub ppt range, making this method suitable for testing compliance with the guidelines/ limits set in both the USA and EU. Recoveries were within the prescribed range of 70-130% and method repeatability was assessed with RSDs <15%. Presenter: Eimear McCall, Waters Corp., Wilmslow, United Kingdom, Email: eimear_mccall@waters.com P-T-004 Sabina Pederiva , Stefania Squadrone , Paola Brizio , Caterina Stella , Giorgio Colombero , Marco Rizzi , Angelo Ferrari , Maria Cesarina Abete , Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d’Aosta, CReAA, National Reference Centre for the Surveillance and Monitoring of Animal Feed, Turin, Italy; Dario Dutto , Veterinary Service ASL Cuneo 1, Cuneo, Italy A First Monitoring of Nickel in the Livestock Food Chain (Northwestern Italy) Nickel (Ni) has an important role both in industrial sector and as essential element in plants, but high concentration could exert toxicity on living beings, as recently highlighted by EFSA opinion (2015). In 2016, following the Commission Recommendations (EU) n°1110 and n°1111 for the monitoring of nickel in feed and food, the National Reference Centre for Surveillance and Monitoring Animal Feed (C.R.e.A.A.) developed and validated an analytical method to detect nickel in these matrices. To investigate a possible cross-over phenomenon, complete food ration, drinking water, individual milk collected without the milk- ing machine and mass milk collected by milking machine were sampled. Samples were homogenized and quantified by Z-ETA- AAS at 232.0 nm after a step of microwave digestion, performed by an ETHOS 1 Milestone S.r.l (Sorisole, BG, Italy), adding 7.5 mL of HNO 3 , 2 mL of H 2 O 2 and 0.7 mL of HF to 0.5 g of sample. The estimated LOD and LOQ were respectively 0.060 and 0.20 mg/kg. The results (median values) showed the presence of nickel in complete feed and hay (respectively 2.8 mg/kg and 0.90 mg/kg) whereas in water and milk Ni concentrations were <0.020 mg/kg, suggesting no contamination from the milking machine or biomagnification of Ni through the livestock food chain. Moreover our results are consistent with literature findings from Brazil, Pakistan, Italy and Spain (range <0.010 mg/kg to

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