Media Releases

Dangerous chemicals in food wrappers likely migrating to humans: U of T study

November 8, 2010

TORONTO, ON — Uni­ver­si­ty of Toron­to sci­en­tists have found that chem­i­cals used to line junk food wrap­pers and microwave pop­corn bags are migrat­ing into food and being ingest­ed by peo­ple where they are con­tribut­ing to chem­i­cal con­t­a­m­i­na­tion observed in blood.

Per­flu­o­ri­nat­ed car­boxylic acids or PFCAs are the break­down prod­ucts of chem­i­cals used to make non-stick and water- and stain-repel­lant prod­ucts rang­ing from kitchen pans to cloth­ing to food pack­ag­ing.  PFCAs, the best known of which is per­flu­o­rooc­tanoic acid (PFOA), are found in humans all around the world.

“We sus­pect­ed that a major source of human PFCA expo­sure may be the con­sump­tion and metab­o­lism of poly­flu­o­roalkyl phos­phate esters or PAPs,” says Jes­si­ca D’eon, a grad­u­ate stu­dent in the Uni­ver­si­ty of Toronto’s Depart­ment of Chem­istry. “PAPs are applied as grease­proof­ing agents to paper food con­tact pack­ag­ing such as fast food wrap­pers and microwave pop­corn bags.”

In the U of T study, rats were exposed to PAPs either oral­ly or by injec­tion and mon­i­tored for a three-week peri­od to track the con­cen­tra­tions of the PAPs and PFCA metabo­lites, includ­ing PFOA, in their blood. Human expo­sure to PAPs had already been estab­lished by the sci­en­tists in a pre­vi­ous study.  Researchers used the PAP con­cen­tra­tions pre­vi­ous­ly observed in human blood togeth­er with the PAP and PFCA con­cen­tra­tions observed in the rats to cal­cu­late human PFOA expo­sure from PAP metab­o­lism.

“We found the con­cen­tra­tions of PFOA from PAP metab­o­lism to be sig­nif­i­cant and con­clud­ed that the metab­o­lism of PAPs could be a major source of human expo­sure to PFOA, as well as oth­er PFCAs,” says Scott Mabury, the lead researcher and a pro­fes­sor in the Depart­ment of Chem­istry at the Uni­ver­si­ty of Toron­to.

“This dis­cov­ery is impor­tant because we would like to con­trol human chem­i­cal expo­sure, but this is only pos­si­ble if we under­stand the source of this expo­sure.  In addi­tion, some try to locate the blame for human expo­sure on envi­ron­men­tal con­t­a­m­i­na­tion that result­ed from past chem­i­cal use rather than the chem­i­cals that are cur­rent­ly in pro­duc­tion.

“In this study we clear­ly demon­strate that the cur­rent use of PAPs in food con­tact appli­ca­tions does result in human expo­sure to PFCAs, includ­ing PFOA.  We can­not tell whether PAPs are the sole source of human PFOA expo­sure or even the most impor­tant, but we can say unequiv­o­cal­ly that PAPs are a source and the evi­dence from this study sug­gests this could be sig­nif­i­cant.”

Reg­u­la­to­ry inter­est in human expo­sure to PAPs has been grow­ing.  Gov­ern­ments in Cana­da, the Unit­ed States and Europe have sig­naled their inten­tions to begin exten­sive and longer-term mon­i­tor­ing pro­grams for these chem­i­cals.  The results of this inves­ti­ga­tion pro­vide valu­able addi­tion­al infor­ma­tion to such reg­u­la­to­ry bod­ies to inform pol­i­cy regard­ing the use of PAPs in food con­tact appli­ca­tions.

The study was con­duct­ed by Jes­si­ca D’eon and Scott Mabury of the Uni­ver­si­ty of Toronto’s Depart­ment of Chem­istry and is pub­lished today in Envi­ron­men­tal Health Per­spec­tives.  Research was fund­ed by the Nat­ur­al Sci­ences and Engi­neer­ing Research Coun­cil of Cana­da.


For more infor­ma­tion, please con­tact:

Jes­si­ca D’eon
Depart­ment of Chem­istry

Scott Mabury
Depart­ment of Chem­istry

Kim Luke
Fac­ul­ty of Arts & Sci­ence
Uni­ver­si­ty of Toron­to