In answer to the objection that urine tests reveal only very recent use of hard drugs, Bruce Reed says that before long, drug-testing technology will have advanced from urine to hair tests, which may reveal chemical traces for up to a year.
Urine tests can reveal use of drugs up to a year afterwards.
mnli hypothesis: Urine tests can reveal use of drugs up to a year afterwards. premise: In answer to the objection that urine tests reveal only very recent use of hard drugs, Bruce Reed says that before long, drug-testing technology will have advanced from urine to hair tests, which may reveal chemical traces for up to a year.