Title:

Developing a standardized water-based brewing protocol for Labrador tea

Abstract:

Labrador tea (Rhododendron groenlandicum) is a plant native to boreal forests worldwide. Many Indigenous Peoples use tea from its leaves for various ailments such as sore throats and indigestion. Bigstone Cree Nation in Alberta (AB) is concerned about the use of glyphosate-based herbicides (GBH) in the forestry industry, and its potential impact on traditional plants and medicines like Labrador tea. Therefore, Bigstone Cree Nation initiated a collaborative investigation on GBH residues altering the plant's medicinal properties. The first objective was to develop a standardized protocol for a water-based Labrador tea infusion, similar to the preparation by Bigstone Cree Nation members, for use in lab studies. Guided by a Bigstone Cree Nation Elder, Labrador tea leaves were picked in Wabasca-Desmarais (AB) to test various brewing methods in medicinal plant books and cookbooks, discussions with Bigstone Cree Nation Elders, and prior scientific reports. Instructions included brewing 1 tablespoon (tbsp) of leaves in 1 cup of water for 3 minutes, 50-75 leaves in 1L of water for 5 minutes, a pinch of leaves per cup for 5-10 minutes, 1 tbsp of leaves per pint of water for 20 minutes, a handful of leaves in a kettle for 15-20 minutes, 5g of tea leaves per cup, and 30 leaves per cup. For each of these conditions, we recorded leaf counts and the average weight in a standard measure (e.g., tbsp, handful, counts). Once we established average weights for the tea leaves, we brewed tea using the following conditions: 1 tbsp of leaves (0.80g), 30 leaves (0.64g), 75 leaves (1.67g), and 5g of leaves in 1 cup (250ml) of boiling double-distilled water, left to steep for 3, 5, 10, 15, and 20 minutes. Photos were taken at each brewing time. The next steps include showing the photos of the tea to Bigstone Cree Nation community members to assess if these protocols match their tea preparation, chemical analysis of the prepared tea, and use of the tea in cell-based assays.