I am still making up my mind whether to try Ernie Ball's Cobalt covered strings. However, is has come to my attention that Cobalt can cause some very significant health issues. There is a famous case with a Canadian brewery which killed a while bunch of people when they used Cobalt to control the foam on the beer (***, anyway?). Cobalt is also a top contender for skin contact allergies. Is there anything out there that looks at using Cobalt in strings and recommend or disrecommends them?