Table 1.

Distribution of thresholds of hypoxia for different groups of benthic organisms

Organisms	LC50, mg O2/liter	SLC50, mg O2/liter	LT50, h
Fish
Mean ± SE	1.54 ± 0.07	4.41 ± 0.39	59.9 ± 12.3
90th percentile	2.51	8.09	0.9
n	77	34	39
Crustaceans
Mean ± SE	2.45 ± 0.14	3.21 ± 0.28	55.5 ± 12.4
90th percentile	5.72	5.0	1.0
n	168	30	102
Gastropods
Mean ± SE	0.89 ± 0.11
90th percentile	1.62
n	12
Bivalves	1.42 ± 0.14
Mean ± SE
90th percentile	3.43
n	19
Molluscs
Mean ± SE		1.99 ± 0.16	412.9 ± 37.3
90th percentile		2.83	55.4
n		28	239
Annelids
Mean ± SE		1.20 ± 0.25	132.2 ± 18.7
90th percentile		1.37	37.8
n		10	43
Echinoderms
Mean ± SE		1.22 ± 0.22	201.1 ± 44.8
90th percentile		2.12	33.6
n		8	23
Cnidarians
Mean ± SE		0.69 ± 0.11	232.5 ± 114.4
90th percentile		1.43	24
n		19	8
Priapulids
Mean ± SE			1512.0 ± 684.0
90th percentile			820.8
n			3

Shown are mean ± SE, 90th percentile (10th percentile for lethal times), and number of observations of LC₅₀, SLC₅₀, and LT₅₀ for the various groups.