Click on a circle in the chart to view Sham immigration records. You can find out when most of the Sham families immigrated to the United States. You can focus your search to immigration records dating from that era. Immigration records can tell you an ancestor's name, ship name, port of departure, port of arrival and destination.
Probably, however...: As my colleague dr. Pappas mentions, marijuana is almost always tested in urine rather than blood, so someone would almost certainly pass a blood test but is more likely to face a urine test.
Approximately 90 percent of drug tests are done as urine tests. Other tests using saliva, hair, sweat and blood samples can also analyze and detect traces of marijuana in your system. Hair testing provides a longer window of detection than urine and can detect drugs taken within the past 90 days.