There are methods of decontamination of artifact contaminated with  hazardous 
materials (other than radioactive items), if you work with a licensed  and 
qualified professional. For example, many companies decontaminate  petrochemical 
soils with biological agents and artifacts can be handled the same  way. I 
have read Adrian Praetzellis and Julia Costello's article and Roberta  Greenwood 
and (?) Hale's counter article and side with those who do not believe  in 
"throwing the baby out with the bathwater." Archaeological sites and  artifacts 
are one day going to be extinct and I feel those of us who happened to  live 
and view them should conserve what we have for the future.
 
Ron May
Legacy 106, Inc.