is cooked, its shell's color changes from blue to orange because the heat from cooking breaks down a protein called crustacyanin, which suppresses the orange hue of the chemical astaxanthin, which is also found in the shell. According to the United States Food and Drug Administration (FDA), the mean level of mercury in American lobster between 2005 and 2007 was 0.107ppm. History Humans have eaten lobster since the prehistoric period. Large piles of lobster shells near areas populated by fishing communities attest to the crustacean's extreme popularity during this period. Evidence indicates that lobster was being consumed as a regular food product in fishing communities along the shores of Britain, South Africa ~100,000 years ago, Australia, and Papua New Guinea ~35,000 years ago. Lobster became a significant source of nutrients among European coastal dwellers. Historians suggest lobster was an important secondary food source for most European coastal dwellers, and it was a primary food source for coastal communities in Britain during this time. Lobster became a popular mid-range delicacy during the mid to late Roman period. The price of lobster could vary widely due to various factors, but evidence indicates that lobster was regularly transported inland over long distances to meet popular demand. A mosaic found in the ruins of Pompeii suggests that the spiny lobster was of considerable interest to the Roman population during the early imperial period. Lobster was a popular food among the Moche people of Peru between 50 CE and 800 CE. Besides its use as food, lobster shells were also used to create a light pink dye, ornaments, and tools. A mass-produced lobster-shaped effigy vessel dated to this period attests to lobster's popularity at this time, though the purpose of this vessel has not been identified. The Viking period saw an increase in lobster and other shellfish consumption among northern Europeans. This can be attributed to the overall increase in marine activity due to the development of better boats and the increasing cultural investment in building ships and training sailors. The consumption of marine life went up overall in this period, and the consumption of lobster went up in accordance with this general trend. Unlike fish, however, lobster had to be cooked within two days of leaving salt water, limiting the availability of lobster to inland dwellers. Thus lobster, more than fish, became a food primarily available to the relatively well-off, at least among non-coastal