Table 2.

Acute-chronic relationships for algal inhibition and sample sizes associated with each.

Metric	Based on	Comparison	# of chemicals	ACR geomean:
Biomass	All Data	EbC50 vs EbC10	87	4.85
Biomass	All Data	EbC50 vs NOECb	94	4.29
Biomass	Over-all	Biomass data	-	4.56
Growth Rate	All Data	ErC50 vs ErC10	61	3.22
Growth Rate	All Data	ErC50 vs NOECr	433	2.43
Growth Rate	Over-all	Growth rate data	-	3.93
Growth Rate	Endpoint Over-all	All data combined	-	3.57
Growth Rate	Raphidocelis subcapitata	ErC50 vs NOECr	349	4.64
Growth Rate	Desmodesmus subspicatus	ErC50 vs NOECr	16	4.21
Growth Rate	Chlorella pyrenoidosa	ErC50 vs NOECr	7	3.06
Growth Rate	Skeletonema costatum	ErC50 vs NOECr	9	3.12
Growth Rate	Chlamydomonas reinhardtii	ErC50 vs NOECr	7	3.06
Growth Rate	Single Species Over-all	ErC50 vs NOECr	-	3.56
Growth Rate	Chemical Class: Neutral Organics	ErC50 vs NOECr	56	4.32
Growth Rate	Chemical Class: Phenols	ErC50 vs NOECr	42	5.35
Growth Rate	Chemical Class: Aliphatic Amines	ErC50 vs NOECr	33	4.71
Growth Rate	Chemical Class: Anilines	ErC50 vs NOECr	29	4.85
Growth Rate	Chemical Class: Esters	ErC50 vs NOECr	26	4.26
Growth Rate	Chemical Class Over-all	ErC50 vs NOECr	-	4.68
Growth Rate	MOA: Narcotics	ErC50 vs NOECr	218	4.82
Growth Rate	MOA: Unspecified	ErC50 vs NOECr	110	3.99
Growth Rate	MOA: Specifics	ErC50 vs NOECr	65	5.62
Growth Rate	MOA: Herbicides	ErC50 vs NOECr	26	4.18
Growth Rate	MOA Over-all	ErC50 vs NOECr	-	4.61
Overall ACR	-	-	-	4.07