Photo of tuna at Tsukiji Market in Tokyo courtesy Tien Mao. Hold onto your chopsticks; the Times recently commissioned a toxicology report on sushi from 13 local establishments and got back some rather unappetizing results:More than half of the restaurants and stores surveyed sold sushi with so much mercury that eating just six pieces a week would exceed the amount the EPA says can be safely consumed by an adult of average weight, which the......