1 A highly toxic form (methylmercury) builds up in fish, shellfish and animals that eat fish. 2  Fish and shellfish are the main sources of methylmercury exposure to humans.3  Mercury exposure at high levels can harm the brain, heart, kidneys, lungs, and immune system. A highly toxic form (methylmercury) builds up in fish, shellfish and animals that eat fish. 2  Fish and shellfish are the main sources of methylmercury exposure to humans.
The 2016 Boston Marathon will begin on Monday, April 18. Here is some of the basic information you should know about the historic event. Length: According to Olympic standards, marathons are 26 miles and 385 yards, or roughly 26.2 miles long. Route: The Boston Marathon starts on Main Street in Hopkinton, Mass.
Competitors during the 2014 Orlen Warsaw Marathon. The marathon is a long-distance running race with an official distance of 42.195 kilometres (26.219 miles, or 26 miles 385 yards), usually run as a road race. The event was instituted in commemoration of the fabled run of the Greek soldier Pheidippides, a messenger from the Battle of Marathon to Athens, who reported the victory.