A U.S.
Images
All items in this gallery are considered public domain unless otherwise noted.
![Scientist sitting next to a biological safety cabinet in a laboratory](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/scientist_with_laboratory_hood_p1010431_crop.jpg?itok=o-I0v4Rx)
![This is an example of a 72 hour post fertilization fli1:egfp zebrafish (3 millimeters long) imaged under transmitted light](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/ctt_leet_72hpf_fli1_tl_control_example_with_text_1024.jpg?itok=WWJgc4i-)
This is an example of a 72 hour post fertilization fli1:egfp zebrafish (3 millimeters long) imaged under transmitted light. The same imaging system with was used.
This is an example of a 72 hour post fertilization fli1:egfp zebrafish (3 millimeters long) imaged under transmitted light. The same imaging system with was used.
![High-Content Screening Laboratory -- Columbia, Missouri](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/imagexpress_crop_qc_0.jpg?itok=fXRmHEMC)
High-Content Screening Laboratory -- Columbia, Missouri
High-Content Screening Laboratory -- Columbia, Missouri
![Behavioral Toxicology Laboratory -- Columbia, Missouri](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/swimming_behavior_tests_puglis_qc.jpg?itok=OqIGzfCV)
Behavioral Toxicology Laboratory -- Columbia, Missouri. Swimming paths of control (left) and copper (right) exposed fish
Behavioral Toxicology Laboratory -- Columbia, Missouri. Swimming paths of control (left) and copper (right) exposed fish
![Swimming paths of control (left) and copper (right) exposed fish demonstrate changes in swimming behavior](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/ctt_puglis_swimming_behavior_tests_puglis_l.jpg?itok=QiHefeI6)
Behavioral Toxicology Laboratory — Columbia, Missouri. Swimming paths of control (left) and copper (right) exposed fish demonstrate changes in swimming behavior detected following exposure to metals. Such changes can impact ability of fish to survive.
Behavioral Toxicology Laboratory — Columbia, Missouri. Swimming paths of control (left) and copper (right) exposed fish demonstrate changes in swimming behavior detected following exposure to metals. Such changes can impact ability of fish to survive.
![Multimode, microplate reader used for the measurement of optical density, fluorescence, and luminescence in biological screening](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/ctt_iwanowicz_plater_reader_1024.jpg?itok=-rXIEW7w)
Multimode, microplate reader
![The zebrafish developmental cardiovascular toxicity high-content screening assay uses a 384-well plate format](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/ctt_leet_384_well_plate_1024.jpg?itok=KVYEeZRq)
The zebrafish developmental cardiovascular toxicity high-content screening assay uses a 384-well plate format to maximize number of treatments and replicates possible on each plate.
The zebrafish developmental cardiovascular toxicity high-content screening assay uses a 384-well plate format to maximize number of treatments and replicates possible on each plate.
![Molecular Devices ImageXpress† High-Content Imaging System](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/ctt_leet_imagexpress_crop_l.jpg?itok=SkL467kY)
High-Content Screening Laboratory — Columbia, Missouri. Molecular Devices ImageXpress† High-Content Imaging System
High-Content Screening Laboratory — Columbia, Missouri. Molecular Devices ImageXpress† High-Content Imaging System
![Screen capture of primary hepatocytes isolated from experimental smallmouth bass (Micropterus dolomieu) visualized](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/ctt_iwanowicz_cell_analysis_1024.jpg?itok=Cbfa6_tk)
Screen capture of primary hepatocytes isolated from experimental smallmouth bass (Micropterus dolomieu) visualized following image-based flow cytometric analysis
Screen capture of primary hepatocytes isolated from experimental smallmouth bass (Micropterus dolomieu) visualized following image-based flow cytometric analysis
![U.S. Geological Survey (USGS) scientist preparing plates for yeast bioassay screening of surface water extracts](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/ctt_iwanowicz_at_hood_1024_0.jpg?itok=d9vM61hK)
USGS scientists working at laboratory fume hood
USGS scientists working at laboratory fume hood
![Attribution of storm-weighted potential contaminant hazard ranks to sampling locations](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/ctt_jones_contaminant_hazard_rank_map_l.jpg?itok=eSUIG4F7)
Geospatial Analyses and Applications — Salt Lake City, Utah. Attribution of storm-weighted potential contaminant hazard ranks to sampling locations in the Sediment-Bound Contaminant Resiliency and Response (SCoRR) network.
Geospatial Analyses and Applications — Salt Lake City, Utah. Attribution of storm-weighted potential contaminant hazard ranks to sampling locations in the Sediment-Bound Contaminant Resiliency and Response (SCoRR) network.
![USGS scientist examining human breast cancer cells under a microscope](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/scientist_with_microscope_p1010329_crop_l.jpg?itok=Kfp0HpzX)
USGS scientist examining human breast cancer cells under a microscope in the cell bioassay laboratory at Columbia Environmental Research Center. Behind the scientist is an automated liquid handling system for dispensing reagents into multi-well micropates for bioassay experiments.
USGS scientist examining human breast cancer cells under a microscope in the cell bioassay laboratory at Columbia Environmental Research Center. Behind the scientist is an automated liquid handling system for dispensing reagents into multi-well micropates for bioassay experiments.
![Gas chromatograph-mass spectrometer (GCMS) used for pesticide analysis](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/ctt_hladik_gcms_new_1024.jpg?itok=g8Si6Tcf)
Organic Chemistry Research Laboratory — Sacramento, California. Gas chromatograph-mass spectrometer - GCMS
Organic Chemistry Research Laboratory — Sacramento, California. Gas chromatograph-mass spectrometer - GCMS
![Fathead minnows (Pimephales promelas) swimming in an experimental aquarium](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/fathead_minnows_in_experimental_aquarium_barber_crop_1024.jpg?itok=r5RaWpfN)
Fathead minnows (Pimephales promelas) swimming in an expermental aquaium. The aquarium is part of an experiment to assess endocrine disruption in fish.
Fathead minnows (Pimephales promelas) swimming in an expermental aquaium. The aquarium is part of an experiment to assess endocrine disruption in fish.
![Bioactive Chemicals Research Laboratory -- Boulder, Colorado](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/fathead_minnows_in_experimental_aquarium_barber_crop_qc_0.jpg?itok=l1331G-5)
Bioactive Chemicals Research Laboratory -- Boulder, Colorado. Fathead minnows (Pimephales promelas) swimming in an expermental aquaium
Bioactive Chemicals Research Laboratory -- Boulder, Colorado. Fathead minnows (Pimephales promelas) swimming in an expermental aquaium
![USGS scientist preparing to measure cyanotoxins in water samples using an automated enzyme-linked immunosorbent assay (ELISA)](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/ctt_loftin_automated_elisa_instrument_img_4517_1024.jpg?itok=jBJXSNXm)
USGS) scientist preparing to measure cyanotoxins in water samples using an automated enzyme-linked immunosorbent assay (ELISA) instrument
USGS) scientist preparing to measure cyanotoxins in water samples using an automated enzyme-linked immunosorbent assay (ELISA) instrument
![Pressurized fluid extractor used to extract organic compounds from solid samples](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/ctt_ogrl_pressurized_fluid_extractor_img_6942_crop_1024.jpg?itok=kbslc9K8)
Organic Geochemistry Research Laboratory — Lawrence, Kansas. Pressurized Fluid Extractor
Organic Geochemistry Research Laboratory — Lawrence, Kansas. Pressurized Fluid Extractor
View of the new (2018) instrument laboratory at the Organic Geochemistry Research Laboratory (OGRL), Lawrence, Kansas. View of a row of instruments in the laboratory.
View of the new (2018) instrument laboratory at the Organic Geochemistry Research Laboratory (OGRL), Lawrence, Kansas. View of a row of instruments in the laboratory.
![U.S. Geological Survey (USGS) scientists working on a time-of-flight mass spectrometer used for the analysis of pesticides](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/ctt_ogrl_working_on_time-of-flight_mass_spec_img_6948_crop_1024_0.jpg?itok=YPVNta7M)
Organic Geochemistry Research Laboratory — Lawrence, Kansas. Scientists working on at time-of-flight mass spectrometer
Organic Geochemistry Research Laboratory — Lawrence, Kansas. Scientists working on at time-of-flight mass spectrometer
![View of the new (2018) sample processing laboratory at the Organic Geochemistry Research Laboratory (OGRL), Lawrence, Kansas](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/ctt_ogrl_sample_processing_laboratory_img_6959_crop_1024_0.jpg?itok=obqqHC6G)
Organic Geochemistry Research Laboratory — Lawrence, Kansas. Sample processing laboratory.
Organic Geochemistry Research Laboratory — Lawrence, Kansas. Sample processing laboratory.
![Image-based flow cytometer for cell population analysis](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/ctt_iwanowicz_flow_cytometer_1024.jpg?itok=My5P4_rl)
Image-based flow cytometer for cell population analysis
Image-based flow cytometer for cell population analysis