<prompt> In chronic arsenic poisoning the following samples can be sent for laboratory examination, except -Nail clippingHair samplesBone biopsyBlood sample  <response>: Arsenic is rapidly cleared from blood.so a blood sample is only useful for acute poisoning Ref: K.S.Narayan Reddys Synopsis of Forensic Medicine and Toxicology, 29th edition, Chapter 26, page 295. 