Use of Semipermeable Polymeric Membrane Devices to Monitor Organic Contaminants in Lincoln Creek, Milwaukee, Wisconsin
File(s)
Date
1994-10Author
DeVita, William M.
Publisher
University of Wisconsin-Stevens Point, College of Natural Resources
Metadata
Show full item recordAbstract
Semipermeable polymeric membrane devices (SPMDs) were evaluated as
concentrators of nonpolar organic contaminants in Lincoln Creek, an urban stream in
Milwaukee, WI. There were no significant levels of polychlorinated biphenyls
(PCBs) or organochlorine pesticides (OCls) detected, consequently, this report focuses
on polynuclear aromatic hydrocarbons (PAHs).
SPMD method detection limits (MDLs) were determined for PCBs, OCls and
PAHs. Values ranged from .004 μg/g for mono- and dichlorobiphenyl (PCBs) to 1.0
μg/g for benzo(g,h,i)perylene, however, most MDLs ranged from .050 to .100 μg/g.
SPMD methodology demonstrates excellent reproducibility with percent coefficients of
variance (%CV) less than 30 and are effective concentrators of biologically available
PAHs.
A pilot study initiated in October, 1993, revealed 11 of 16 targeted PAHs
were detected in SPMDs deployed for 21 days. Fluoranthene, pyrene and chrysene
(PAHs) were of highest concentration. Composite sediment samples collected
upstream of the SPMD exposure site were also analyzed and 14 of 16 PAHs were
detected. Differences in PAH concentrations occur between SPMDs and sediments.
Higher concentrations of larger molecular dimension and higher Kow PAHs in
sediment samples was noted.
Frequency and intensity of storm events affect loading of P AHs into Lincoln
Creek . An r^2 value of .9657 was obtained when comparing storm events occurring
over a 30-day period to total PAHs accumulated in SPMDs.
SPMDs and fathead minnows (Pimephales promelas) were simultaneously
deployed during five, 30-day exposure periods between April 17 and September 19,
1993. Total SPMD accumulated PAHs ranged from 9.1 to 30.1 μg/g with
fluoranthene, pyrene and chrysene accounting for an average of 72 % of this total.
Fathead minnows accumulated PAHs ranging from 0.20 to 11.6 μg/g (lipid
normalized). Rusty crayfish (Orconectes rusticus) were deployed during two 30-day
periods and accumulated PAHs at 3.0 and 7.2 μg/g (lipid normalized).
SPMDs, fathead minnows, and rusty crayfish were simultaneously exposed for
30 days between July 21 and August 20, 1993, and sampled on days 2, 4, 8, 16, 24
and 30 to record uptake of PAHs, PCBs, and OCls. Fluoranthene, pyrene, and
chrysene were detected in SPMDs at levels of 5.8, 4.5, and 2.7 μg/g respectively by
day 30. Four and five-ringed PAHs appear to be in the linear region of the uptake
curve into SPMDs while three-ringed PAHs appear to reach equilibrium during this
30-day exposure. Fathead minnow and rusty crayfish P AH curves demonstrate
metabolism and elimination of contaminants despite further inputs of PAHs into
Lincoln Creek from storm water runoff. Three-ringed PAHs appear to exhibit faster
rates of uptake and depuration in all three sample matrices.
Hexane-filled SPMDs were exposed concurrently with lipid-filled SPMDs to
compare accumulation efficiency of these two sampling devices. Retention of hexane
in SPMDs was variable with up to 96% loss of the initial 100 mL hexane by the low
density polyethylene (LOPE) membrane. Lipid-filled SPMDs accumulated 1.5 to 22
times PAH levels found in hexane-filled SPMDs. Hexane SPMDs produced
unacceptable %CVs for the most abundant PAHs, fluoranthene, pyrene, and chrysene,
at 85, 62, and 75 percent respectively. Lipid SPMDs produced %CVs of 7.3, 6.6,
and 5.1 for the same compounds respectively. Reduction in uptake of contaminants
into SPMDs due to biofouling of LPDE was investigated during one 30-day exposure.
SPMDs which were periodically cleaned displayed an average of 41% higher
concentration of PAHs than those which were not cleaned. Four additional PAHs
were detected in cleaned SPMDs.