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.
A half-marathon is 13.1 miles, and a standard marathon is 26.2 miles. ANYTHING that is longer than 26.2 miles is considered to be an Ultra-Marathon. They have distances ranging from 50K (31.1 miles) on up to 100 MILES! My first marathon was the 1991 Marine Corps Marathon. 5k run is 5 kilometers (3.11 mi), and a 10k would be 10 Kilometers (6.21 mi). A marathon is 42.195 kilometres (26 miles 385 yards) and a half marathon is 21.0975 kilometers, or 13 7/64 miles, about 13.1 miles.