Ironically the lead itself is sometimes the source of the radiation causing problems (Pb-210). One small benefit of lead free electronics!<p>Some experiments have used 2000 year old Roman lead to avoid this <a href="http:&#x2F;&#x2F;www.nature.com&#x2F;news&#x2F;2010&#x2F;100415&#x2F;full&#x2F;news.2010.186.html" rel="nofollow">http:&#x2F;&#x2F;www.nature.com&#x2F;news&#x2F;2010&#x2F;100415&#x2F;full&#x2F;news.2010.186.ht...</a><p>See also <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Low-background_steel" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Low-background_steel</a>