Concord Journal 2/11/09: Scientist: Tests show turf fields are safe. After a Boston Globe article reported on lead in the yellow boundary lines of local artificial turf fields, and in the green carpet at Concord-Carlisle, the Concord Board of Selectmen brought in an expert. Laura Green is an MIT lecturer who has spent 30 years studying the way the land children play on affects them. She concluded “I cannot find a risk here.” She said, “I’m quite confident, both because the total lead content is very low and the bioavailability [of lead within the plastic blades of grass] is unmeasurable.”