Table 7. Dissolved water concentrations of select compounds estimated from semipermeable membrane devices (SPMDs) at three sites in the McKenzie River basin, Oregon, September–October 2007.

[A and B are replicate samples. Water concentrations were estimated from quantified SPMD data using methods described in the section, ‘Estimation of Ambient Water Concentrations.’ nd, not detected in passive sampler; NQ, not quantified--compound detected in passive sampler at a concentration less than the method quantitation limit; detections are highlighted as bold type in shaded cells; HBSL, health-based screening level (Toccalino and others, 2008)]

Compounds	Concentrations, in picograms per liter
	Water treatment plant inlet			Cedar Creek			Camp Creek
	A	B		A	B		A	B
Fluorene1	nd	nd		NQ	140		240	140
Chrysene2	nd	nd		NQ	95		nd	nd
2-methylphenanthrene2	nd	nd		NQ	100		190	96
Pentachloroanisole2	18	65		130	170		370	150
trans-Chlordane2	NQ	NQ		NQ	NQ		NQ	16
trans-Nonachlor2	nd	nd		NQ	NQ		nd	13
Endosulfan3	nd	nd		NQ	NQ		NQ	280
p,p'-DDT4	NQ	NQ		NQ	NQ		41	NQ

¹ HBSL for fluorene is 300 micrograms per liter, more than 1 million times greater than the maximum concentration estimated from SPMD data during the current study.

² No toxicity data available.

³ HBSL for endosulfan is 40 micrograms per liter, more than 100,000 times greater than the maximum concentration estimated from SPMD data during the current study.

⁴ HSBL for p,p’-DDT ranges from 0.1 to 10 micrograms per liter, from 2,000 to more than 200,000 times greater than the maximum concentration estimated from SPMD data during the current study.