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Dalma Martinovic-Weigelt

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In crude-oil-contaminant plumes the dissolved organic carbon (DOC) is mainly hydrocarbon degradation intermediates only partly quantified by the diesel range total petroleum hydrocarbon (TPHd) method. To understand potential biological effects of degradation intermediates we tested three fractions of DOC: (1) solid phase extract (HLB); (2) dichloromethane (DCM-total) extract used in TPHd; and (3) DCM extract with hydrocarbons isolated by silica gel cleanup (DCM-SGC). Bioactivity of extracts from five wells spanning a range of DOC was tested using an in vitro multiplex reporter system that evaluates modulation of activity of 46 transcription factors; extracts were evaluated at concentrations equivalent to the well...
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The U.S. Geological Survey, National Park Service, St. Cloud State University, and the University of St. Thomas conducted a cooperative study to investigate the occurrence of chemicals of emerging concern (CECs) and potential effects to aquatic biota in select tributaries of the St. Croix River in Minnesota and Wisconsin. In 2011, treated wastewater effluent samples were collected from 22 sites in the St. Croix River Basin to determine total estrogenic activity. In 2012, wastewater effluent was collected at five select locations based on total estrogenicity and analyzed for CECs. In addition, surface water, bottom sediment, resident fish, and resident crayfish were collected upstream and downstream from effluent...
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Management of petroleum-impacted waters by monitored natural attenuation (MNA) requires an understanding of the toxicology of both the original compounds released as well as the transformation products formed during natural breakdown. Here, we report data from a groundwater plume consisting of a mixture of crude oil compounds and transformation products resulting from a crude-oil release in August, 1979 near Bemidji, MN, USA. Water samples were characterized for activation of 52 human nuclear receptor (NR) activities and 50 transcriptional pathways associated with toxic responses. Five replicate analyses were performed for each solution at strengths of 1, 3, and 10 times the sample concentration. Radar plots of...
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This data describes the relative luminescence units (RLUs) and relative fluorescence units (RFUs) of lysates of aryl-hydrocarbon responsive chemically-activated luciferase expression human hepatoma HG2L7.5c1 cells which were exposed for 4 or 24 h to beta-naphthoflavone dilutions, 2,3,7,8-tetrachlorodibenzo-p-dioxin dilutions, or dilutions of groundwater extracts collected from wells within or near an oil-contaminated area. This data also describes RFUs of bovine serum albumin standards which were used to convert the RFUs of the cell lysates to protein with which to normalize the RLUs of the cell lysates.
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Groundwater samples were collected in June 2018 from a background (reference) well located 200 m upgradient from the source and five wells along a flowline in the plume at 39, 68, 102, 125, and 254 m downgradient from the source. Before sampling, at least three times the water volume in the well casing was purged and field parameters (temperature, dissolved oxygen, specific conductance, and pH) were stable. Two samples from each well were collected into unpreserved 1 L amber bottles and shipped on ice overnight to a commercial lab. The two samples were extracted using dichloromethane (DCM; EPA Method 3510). One sample extract was treated with silica gel cleanup (SGC) column (USEPA method 3630C). Aliquots of the...
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