This is Arnel's query (using Allen Browne's ConcatRelated() ):
TRANSFORM First(
ConcatRelated(
"TestedFor",
"Table1",
"DateReportDue=#" & Format([DateReportDue],"m/d/yyyy") & "# And Sample_ID = '" & [Sample_ID] & "'",
"TestedFor",
Chr(13) & Chr(10)
)
) AS TFor
SELECT...