title: Emission of perfluoroalkyl carboxylic acids (PFCA) from heated surfaces made of polytetrafluoroethylene (PTFE) applied in food contact materials and consumer products.
abstract: Polytetrafluoroethylene (PTFE) has been widely discussed as a source of perfluorooctanoic acid (PFOA), which has been used in the production of fluoropolymers. PTFE may also contain unintended perfluoroalkyl carboxylic acids (PFCAs) caused by thermolysis of PTFE, which has been observed at temperatures above 300°C. Common PTFE coated food contact materials and consumer goods are operated at temperatures above 200°C. However, knowledge on possible emissions of PFCAs is limited. Therefore, it was the aim of this study to investigate and evaluate the emission of PFCAs from PTFE coated products with both, normal use and overheating scenarios. Four pans, claimed to be PFOA free, and nine consumer products were investigated. At normal use conditions (<230°C), emissions from PTFE surfaces were trapped for 1h. Overheating scenarios (>260°C) recorded emissions during a 30min heating of empty pans on a stove. Emissions were analyzed by LC-ESI-MS. Results indicate the emission of PFCAs, whereas no perfluorinated sulfonic acids were traced. At normal use conditions total emissions of PFCAs accounted for 4.75ng per hour. Overheated pans, however, released far higher amounts with up to 12190ng PFCAs per hour at 370°C. Dominating contributors where PFBA and PFOA at normal use and PFBA and PFPeA during overheating. Temperature seems to be the main factor controlling the emission of PFCAs. A worst case estimation of human exposure revealed that emissions of PFCAs from heated PTFE surfaces would be far below the TDI of 1500ng PFOA per kg body weight.
authors.affiliation: Fraunhofer-Institut IVV, Giggenhauser Straße 35, 85354 Freising, Germany. Electronic address: martin.schlummer@ivv.fraunhofer.de.
authors.forename: Martin
authors.initials: M
authors.lastname: Schlummer
authors.affiliation: Fraunhofer-Institut IVV, Giggenhauser Straße 35, 85354 Freising, Germany.
authors.forename: Christina
authors.initials: C
authors.lastname: Sölch
authors.affiliation: Fraunhofer-Institut IVV, Giggenhauser Straße 35, 85354 Freising, Germany.
authors.forename: Theresa
authors.initials: T
authors.lastname: Meisel
authors.affiliation: Fraunhofer-Institut IVV, Giggenhauser Straße 35, 85354 Freising, Germany.
authors.forename: Mona
authors.initials: M
authors.lastname: Still
authors.affiliation: Fraunhofer-Institut IVV, Giggenhauser Straße 35, 85354 Freising, Germany.
authors.forename: Ludwig
authors.initials: L
authors.lastname: Gruber
authors.affiliation: Fraunhofer-Institut IVV, Giggenhauser Straße 35, 85354 Freising, Germany.
authors.forename: Gerd
authors.initials: G
authors.lastname: Wolz
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D002210:Caprylates / Q000032:analysis*; D003257:Consumer Product Safety; D003297:Cooking and Eating Utensils; D004784:Environmental Monitoring / Q000379:methods*; D005466:Fluorocarbons / Q000032:analysis*; D005506:Food Contamination / Q000032:analysis / Q000517:prevention & control; D006358:Hot Temperature; D006801:Humans; D011138:Polytetrafluoroethylene / Q000032:analysis*; D013499:Surface Properties
chemical_list: D000393:Air Pollutants; D002210:Caprylates; D005466:Fluorocarbons; D011138:Polytetrafluoroethylene; C023036:perfluorooctanoic acid
keywords: Fluoropolymers; Mechanism; PFAA; Release; Sources