Evaluation of commercially available methamphetamine presumptive tests for site contamination

Figures & data

Table 1. Results from the presumptive tests for each brand (✓ indicates an accurate result, O indicates an incorrect result below the limit of detection, X indicates a false negative result).

Concentration (µg/100 cm^2)	Brand 1	Brand 2	Brand 3^a	Brand 4	Brand 5	Brand 6	Brand 7
0.7	✓✓✓	✓✓✓	✓✓✓	✓✓✓	✓✓✓	✓✓✓	✓✓✓
0.6	✓✓✓	^b	^b	✓✓ X	✓✓✓	^b	✓✓ X
0.5 µg/100 cm^2 – stated limit of detection for all kits
0.24	O O O	✓✓✓	✓✓✓	O O O	O O O	✓✓✓	^b
0.18	O O O	O O ✓	O O ✓	O O O	O O O	O O O	O O O
0	✓✓✓	✓✓✓	✓✓✓	✓✓✓	✓✓✓	✓✓✓	✓✓✓

Most kits were tested three times for each concentration.

^aBrand 3 was out of date and so results should be interpreted with caution.

^bIndicates that this test was not performed on that brand.

Table 2. The quality control data provided to customers in the methamphetamine presumptive test kits.

Brand	Negative (%)	Positive (%)
1	99.38	97.45
2	N/A^a	N/A^a
3	98.2	93.7
4	N/A^a	N/A^a
5	99.38	97.45
6	99.38	97.45
7	N/A^a	N/A^a

^aN/A means that there were no quality control data provided.

Table 3. The components that were Included in the kits that were tested in this study.

	Price per Test AU$	Transit to Adelaide	Swabs	Test	Buffer	Gloves	Template	Glove Change	Blank Test	Quality Control
Brand 1	17	7 days	✓	✓	✓		✓	✓	✓	✓
Brand 2	N/A	N/A	✓	✓	✓	✓
Brand 3	13	7 days	✓	✓	✓	✓	✓			✓
Brand 4	18	2 days	✓	✓	✓	✓
Brand 5	15	15 days	✓	✓	✓		✓	✓	✓	✓
Brand 6	15	16 days	✓	✓	✓		✓	✓	✓	✓
Brand 7	18	7 days	✓	✓	✓		✓