3 research outputs found
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Passive sampling devices as biological surrogates for evaluating seasonal bioavailability of hydrophobic organic contaminants in surface water
The seasonal distribution of bioavailable organochiorine contaminants in surface
water and the potential environmental factors influencing their bioavailability were
evaluated. The study was carried at the lower Willamette River at Portland Harbor, Oregon
where surface water runoff varied according to season. Bioavailable water concentrations of
DDTs and PCBs were determined using a polyethylene membrane containing passive
sampling device (PSD), known as semipermeable membrane device (SPMD). Our findings
indicated that the influence of river seasonality on the bioavailable distributions of
organochiorine contaminants was compound- and site-specific. Bioavailable DDTs
concentrations were strongly affected by the local historic use of DDTs and seasonal changes
in river conditions. The dominance of bioavailable p,p'-DDD and large DDD/DDE ratios
observed during low flow condition in summer suggest redistribution of p,p'-DDD into the
water column and conditions favoring reductive dechlorination of p,p'-DDT to p,p'-DDD. In
contrast, bioavailable dieldrin and PCB concentrations were significantly increased during
high flow condition in fall, especially during episodic rainstorm events. While a discernable
seasonal pattern for PCBs was observed along the 18-mile stretch study area, the seasonal
pattern of dieldrin was only apparent at the sampling site downstream of an agricultural creek
with historical use of dieldrin. The increase in bioavailable PCB concentrations and daily
loads cOincident with high precipitation and sewer overflows in fall suggested a significant
contribution of PCBs from precipitation input and urban storm water discharges to the
surface water. Seasonal bioavailable concentrations of organochiorine compounds exceeded the national and the Oregon water quality criteria revealing the significance of considering
realistic seasonal and site-specific influences on bioavailable organochiorine distributions
when performing risk assessments. In addition, we developed the triolein-free polyethylene
lay flat tubing (LFT) as an alternative in situ PSD. The LFT proved reliable and had the same
benefits as SPMD, but was simpler, inexpensive and lacked interference from the triolein
impurities. The LFT tended to accumulate compounds with high log K0 faster than SPMD.
LFT sampling rates were estimated and modeled for 33 target analytes, including PAHs,
PCBs, and organochiorine pesticides. The successful determination of field derived data
illustrates the effectiveness and reliability of LIT for environmental monitoring
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Bioaccumulation profiles of chemical contaminants in fish from the lower Willamette River, Portland Harbor superfund site and human health risk assessment
Concentrations of twenty-five PCBs, fifteen organochiorine pesticides and mercury were determined in recreational fish from the Willamette River, Oregon during the summer of 2000. Thirty-six fish samples of three fish species including black crappie, smalimouth bass and con-rn-ion carp were analyzed. The data reported here provides new information and recent residue data in fish from the main stem of lower Willamette River. Concentrations of total PCBs and total DDT (sum of p,p'-homologs) in fish varied from 14 to 528 and from 18 to 510 ng/g wet weight, respectively. Fish samples from Portland Harbor superfund site were most contaminated because this river segment is the primary depositional area of the Willamette River system. Among three fish species analyzed, smailmouth bass contained the highest contaminant levels. Distribution profiles of analyzed PCBs were similar in three fish species. Hexachiorobiphenyl congener 153 was the most abundant and pentachiorobiphenyls congeners 118, 101 and heptachiorobiphenyls congeners 180, 187 were second most abundant. Among DDT derivatives, p,p'- DDE was the most abundant species. Other organochlorine pesticides were not detected or present below detection limit. Mercury levels in tested fish were in a range of 0.013 to 0.52 mg!g. Hazard quotient indices (ÎŁHQ>1) indicated consumption of contaminated fish by recreational fishers and subsistence fishers harvesting fish from the lower portion of the river might cause chronic adverse health effects posed by the presence of these chemicals. Total cancer risk at all sites of this study exceeded acceptable lifetime cancer risk level (10â»â”). The greatest contributors to hazard quotients for non-carcinogenic risk and carcinogenic risk were total PCBs and dioxin-like PCBs, respectively. The 10â»â” upper limit of lifetime cancer risk as the health protection standard, suggested no fish consumption in the unit of meals/year for smallmouth bass and black crappie from the lower Willamette River were acceptable because the presence of PCBs were at the concentrations that can pose a long term toxic threat to local fish consumers
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Final report : environmental stresses and skeletal deformities in fish from the Willamette River, Oregon, USA
The Willamette River, one of only 14 American Heritage Rivers, flows through the most densely populated and agriculturally productive region of Oregon. Previous biological monitoring of Willamette River fish detected elevated frequencies of skeletal deformities in fish from certain areas of the lower (NP [NP], rivermile [RM] 26-55) and middle (near Wheatland Ferry [WF], RM 72-74) Willamette River, relative to those in the upper Willamette (i.e. near Corvallis [CV], RM 125-138). The objective of this study was to determine the likely cause of skeletal deformities in populations of Willamette River fish. Characterization of deformity loads in Willamette River fish collected in 2002 and 2003 demonstrated that deformity loads remained 2-3 times greater at the NPPool (NP) and WF locations than those observed at the CV location. There were some differences in water quality parameters between the NP and CV sites, but they did not readily explain the difference in deformity loads. Concentrations of bioavailable metals were below detection limits (â1-5 ”g/L). Concentrations of bioavailable polychlorinated biphenyls (PCBs) and chlorinated pesticides were generally below 0.25 ng/L. Concentrations of bioavailable polycyclic aromatic hydrocarbons were generally less than 5 ng/L. Chlorpyrifos (averaged less than 1.5 ng/L) was the only organophosphate pesticide detected as bioavailable in water. Concentrations of most persistent organic pollutants were below detection limits in ovary/oocyte tissue samples and sediments and those that were detected were not significantly different among sites. Bioassay of Willamette River water extracts provided no evidence that unidentified compounds or the complex mixture of compounds present in the extracts induced skeletal deformities in cyprinid fish. However, metacercariae of a digenean trematode were directly associated with a large portion of the lesions detected in fish collected from the Willamette River and the lesions were reproduced in fathead minnows exposed to cercariae extracted from field collected snails. As a whole, there was very little evidence to suggest that chemical contaminants were responsible for the greater deformity loads observed at NP and WF. Instead, the weight of evidence suggests that parasitic infection was the primary cause of skeletal deformities observed in Willamette River fish.Keywords: Willamette River,
Infection,
Chlorpyrifos,
Polychorinated biphenyls,
Chlorinated pesticides,
Water,
Parasite,
Fish,
Quality,
Environment and Conservation,
Skeleton,
Deformity,
Orego