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.
Your Privacy Rights Canadian Customers. 1  It seems like common sense that to prepare for a marathonâan event that includes a heck of a lot of runningâyour training should also include a heck of a lot of running. Thatâs why marathon preparation dogma preaches that you need to do one long, 12 to 26 mile run each week. The problem: That often puts too much mileage on your body, says Mark Conover, director of the cross-country and track-and-field programs at California Polytechnic State University.