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The Boston Globe

Business

How the Globe tested fish

- One hundred eighty-three fish samples were collected from 134 restaurants, grocery stores, and seafood markets across Massachusetts between May and July. The Globe chose to focus most of its testing on certain species - including red snapper and tuna - because they have been identified by regulators as more likely to be mislabeled.

- Each sample included the receipt and was labeled with the date collected, restaurant or store name, and price. The samples were stored in industrial freezers in a locked room at The Boston Globe.

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- Using a sanitized scalpel, reporters placed small pieces of fish - roughly the size of a Q-tip head - in separate ethanol-filled test tubes supplied to the Globe by officials at the Biodiversity Institute of Ontario at the University of Guelph, which is home to a 26-nation consortium called the International Barcode of Life. One reporter watched the other to make sure sanitizing methods were followed, and to ensure that the correct fish was placed in the proper test tube.

- Photos of each fish sample were entered into a database that linked the image, test tube specimen, and fish sample. A total of 190 test tubes were sent by express mail to the Biodiversity Institute. To validate the results, seven samples were submitted twice.

- Barcode of Life researchers successfully conducted DNA analysis from 179 samples, matching them with a species in their database. Eleven samples were thrown out because the DNA could not be read. The Globe also sent a select group of specimens to a different lab for DNA testing and provided the genetic data of some to a researcher for analysis.

RESULTS: Of the 183 fish samples, 87 were deemed to be mislabeled because they were a different species from the item ordered, or did not meet FDA labeling requirements.

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