Your question is way to inclusive to accurately answer ---the answer is "it depends"----some fish can be perfectly safe to eat and other imports can be quite problematic. Here is a recent short article produced by ABC news in the U.S. I believe that this piece provides one with the appropriate caution. If you are absolutely sure of the store's policies where you shop, go ahead and consume but with the warnings out there--be careful. Here is a statement that can give one pause: "Also this week, (March, 2013) regulators in China closed 180 food plants after uncovering more than 23,000 food safety violations. Despite the crackdown, China denies that its food exports are dangerous." This is a classic case of "caveat emptor" (let the buyer beware) but China is a major exporter of fish so checking the internet for warnings would be wise. It is simply impossible to make a blanket statement about the safety of all fish from China.