Not all workers are allowed to save up to the federal limit, however.
Elected officials and political parties cannot give more than the federal limit directly to candidates.
The levels of mercury in children in the new study were lower than expected, and well below federal limits.
A significant increase is defined as consuming half the available cushion between the federal limit and the current air quality.
Next month, 32,800 families will reach the five-year federal limit for cash welfare assistance.
The federal limit for individual contributions to state and local party committees is a combined total of $10,000 per year.
Hard money is subject to federal limits - $1,000 per person in the general election.
There are also federal and state limits, both under $400,000, on how much a house can cost under the program.
Selected samples from Boston had lead levels that were more than 45 times the federal limit, according to the analysis.
The levels were even below the current federal limits suggested for children.