From Mass Fisheries and Wildlife
COMING IN 2012:
• Lead fishing sinkers and jigs less than 1 ounce will be prohibited in all inland waters of the Commonwealth effective January 1, 2012.
This is all the information we can find at this time. This raises the question about flies weighted with lead. If anyone has more detailed information on this please drop us a line using the Contact Us page.
Update: If the lead is securely fastened to the hook or an integral part of the hook like a jig head it will be OK to use. The law was aimed at small split shot type leads which are easily ingested by wildlife.