“…The rate of fingernail growth has been reported to be approximately about 0.1 mm/day, 0.5 mm/week, 38.1 mm/year, and 2.2-3.0 mm/month (Baden, 1965;Horner and Cohen, 1966;Clark and Buxton, 1938;Lin et al, 2004). To date, amphetamine-type stimulants (Cirimele et al, 1995;Lin et al, 2004;Suzuki et al, 1989), cannabinoids (Lemos et al, 1999), opiates (Lemos et al, 2000b;Ropero-Miller et al, 2000;Cingolani et al, 2004), cocaine (Ropero-Miller et al, 2000;Cingolani et al, 2004;Valente-Campos et al, 2006;Ragoucy-Sengler and Kintz, 2005;Garside et al, 1998;Skopp and Pötsch, 1997), phencyclidine (Jenkins and Engelhart, 2006), benzodiazepines (Irving and Dickson, 2007), and methadone (Lemos et al, 2000a) are among the drugs that have been detected in nails. These studies have been based on several instrumental methods including immunoassay (Lemos et al, 2000a;Lemos et al, 2000b), high performance liquid chromatography (HPLC) (Lemos et al, 2000b), gas chromatography/mass spectrometry (GC-MS) (Lemos et al, 1999;Ropero-Miller et al, 2000;Cingolani 2004;Valente-Campos 2006;Jenkins and Engelhart, 2006), and liquid chromatography/mass spectrometry (LC-MS) (Irving and Dickson, 2007).…”