If you're concerned about the levels of mercury in your seafood, particularly your sushi — and you should be — the Sierra Club is here to help. And not by telling you to go up to Yosemite and catch the fish yourself, with the ghost of John Muir and some fancy duds from REI. Although that's not a bad idea. Instead, the Sierra Club has taken the more convenient hi-tech approach, by creating an app for your iPhone or Android called Safe Sushi.
Launched to coincide with Mercury Awareness Week (Dec. 5-11) and the Obama Administration's first federal controls on mercury emissions from power plants, the app lists 38 varieties of seafood commonly used in sushi and indicates their mercury levels.
Listed alphabetically, from aji (horse mackerel) to awabi (abalone) to ikura (salmon roe) to uni (sea urchin roe), the app categorizes the sushi as high, medium or low in mercury. It also indicates actual mercury levels of each — 0.21 per mil for katsuo (bonito) — and tells you whether the fish is sustainably harvested or unsustainably harvested and therefore better to avoid entirely.
It's a kind of beautiful app, if you like looking at pictures of fish (as sushi, in silhouette), and it also provides a thumbnail graphic sketch of how mercury ends up in the fish food chain. (We just wish they'd added more fish.) It's also extremely important, especially if you have kids — mercury is a neurotoxin — in this sushi-centric town. Finally, a good reason to let them use their iTouches at the omakase bar. Take a picture of that kazunoko (herring roe). Translate “thank you very much” and “may I please have some more” into Japanese on the Translator app. Make sure you can eat what's behind the glass case.