Table 1. Ratios of the 10 most abundant PAHs on average in surface waters of the Portland Harbor Superfund site based on passive sampling during 2010 and 2015, relative to the most abundant by mass PAHs (pyrene).

Surrogate mixtures were constructed based on the aquatic relative concentrations of PAHs in the Superfund site by mass. The highest initial exposure concentrations (1% DMSO) are reported for Supermix10 (SM10), Supermix3 (SM3), and Supermix7(SM7). Mixture ratio represents the ratio of that particular PAH in the mixture.

PAH	Environmental Ratios	Mixture Ratios	Exposure concentration (μM)
			SM10	SM3	SM7
Pyrene	0.50 – 1.0	1.0	24	24	-
Fluoranthene	0.45 – 1.0	1.0	24	-	48
Retene	0.083 – 1.0	0.60	13	12	-
Benzo[a]anthracene	0.053 – 0.15	0.21	4.2	4.4	-
Chrysene	0.068 – 0.26	0.20	4.4	-	8.8
Naphthalene	0.072 – 1.0	0.14	5.9	-	12
Acenaphthene	0.11 – 1.0	0.12	2.9	-	5.8
Phenanthrene	0.16 – 0.45	0.12	3.4	-	6.8
Fluorene	0.10 – 0.32	0.080	3.1	-	6.2
2-methylnaphthalene	0.049 – 0.51	0.052	1.7	-	3.4