Table 1.
Mouse ear swelling tests (MESTs): positive control + three cyanobacteria suspensions + purified cylindrospermopsin
| TEST MATERIAL | Proportion of test mice with ear swelling >20% after challenge | Proportion of test mice with ear swelling >20% after re-challenge | Per cent ear swelling of test group after challenge. Median (range) | Per cent ear swelling of test group after re-challenge. Median (range) | Per cent ear swelling of highest responder control mouse after challenge and re-challenge | Fisher's exact test comparing proportion of ear thickness increases <20% between test and control mice |
| 0.1% DNCB | 100% n= 10 at 24 hrs n = 9 at 24 & 48 hrs |
Not done | 68.6 (16.4 – 130.0) | Not done | Not done | |
| 2% w/v M. aeruginosa microcystins 13.6 μg/mL | 0 | 0 | 1.9 (-11.6 – 10.7) | 1.2 (-1.6 – 10.0) | 8.9 | |
| 2% w/v A. circinalis saxitoxins 6.0 μg/mL | 0 | 0 | 0.0 (-6.8 – 8.2) | 1.5 (-2.9 – 9.5) | 11.7 | |
| 2% w/v C. raciborskii cylindrospermopsin 73 μg/mL | 60% n= 2 at 24 hrs n= 4 at 48 hrs |
60% n = 6 at 24 hrs n = 2 at 24 & 48 hrs |
15.8 (0.0 – 38.9) | 18.3 (2.2 – 47.5) | 10.7 | p = 0.001 |
| 100 μg/mL cylindrospermopsin* | 22% n = 1 at 24 hrs n = 1 at 48 hrs |
44% n = 1 at 24 hrs n = 3 at 48 hrs |
8.1 (-4.8 – 26.1) | 12.6 (4.5 – 49.2) | 4.8 (challenge) 27.8 (re-challenge) |
p = 0.51 (challenge) p = 0.58 (rechallenge) |
* challenge concentration applied to test ears was 50 μg/mL. Rechallenge concentration was 100 μg/mL (= induction concentration).