Table 2 Summary of epidemiological studies investigating recreational exposure to cyanobacteria
| Country; year study conducted; study author/s; reference | Study design | Main outcomes reported | Study size (n) | Odds ratio (95% confidence interval) |
|---|---|---|---|---|
| UK, 1990 Philipp [86] | Cross-sectional | No statistically significant findings | 246 | |
| UK, 1990 Philipp & Bates [87] | Cross-sectional | No statistically significant findings | 363 | |
| UK, 1990 Philipp et al [88] | Cross-sectional | No statistically significant findings | 246 | |
| Australia, 1992 El Saadi et al [89] | Case-control | No statistically significant findings | Approx. 48 (subjects reporting recreational exposure) | |
| Australia, 1995 Pilotto et al [90] | Prospective cohort | Increased symptoms at 7 days following exposure to more than 5,000 cyanobacterial cells/mL for >1 hour vs non-bathers |
852 (total) 338 (no prior exposure or symptoms) |
1.3 (0.7–2.6) 3.4 (1.1–10.8) |
| Australia & USA, 1999–2002 Stewart et al [91] | Prospective cohort | Increased reporting of mild respiratory symptoms and any symptom at 3 days following exposure to cyanobacteria cell surface area >12 mm2/mL vs <2.4 mm2/mL |
1,331 (total) 1,137 (no prior symptoms) 1,149 (no prior respiratory symptoms) |
1.7 (1.0–2.9) (any symptom) 2.1 (1.1–4.0) (respiratory symptoms) |