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.
The median finishing time for women was 4:45:30 (10:53 minutes per mile pace). Boston Marathon Qualifying Times. For amateur runners, some people use the Boston Marathon qualifying times (BQ) as a measure of a good marathon time. Only a small percentage of marathon runners achieve these times. To qualify for the Boston Marathon, men ages 18 to 34 must run 3:05 or faster, and women in that age group must run 3:35 or faster. After that, additional time is given to older age groups.