How are harmful elements and compounds in plants, soils, rocks, and sediments regulated?

Regulatory limits for safe levels of elements in water and foodstuffs are established by the U.S. Environmental Protection Agency (EPA) and the U.S. Food and Drug Administration (FDA). However, there are generally no regulatory limits that scientists can refer to when dealing with plants, soils, rocks, and sediments. Therefore, to determine whether a plant, soil, rock, or sediment contains a 'high or unusual' quantity of a specific element, it is necessary to determine what quantity is 'normal or usual.' These levels are referred to as background or baseline measurements, but they may be somewhat different.

background measurement represents natural concentrations of an element in natural materials that exclude human influence. This measurement represents an idealized situation and is typically more difficult to measure than a baseline.

baseline measurement represents concentrations measured at some point in time and is not generally a true background. Baseline concentrations are typically expressed as a range, not a single value.

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Does the Earth's magnetic field affect human health?

The Earth's magnetic field does not directly affect human health. Humans evolved to live on this planet. High-altitude pilots and astronauts can experience higher levels of radiation during magnetic storms, but the hazard is due to the radiation, not the magnetic field itself. Geomagnetism can also impact the electrically-based technology that we...

Does the USGS have reports on the background levels of elements in soils and other surficial materials?

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How frequently are volatile organic compounds (VOCs) detected in groundwater?

Volatile organic compounds (VOCs), which are widely used in the manufacture of many products including refrigerants, plastics, adhesives, paints, and petroleum products, have been detected in about one-third of the wells sampled by the National Water-Quality Assessment (NAWQA) Program of the USGS. Chloroform and other trihalomethanes, the most...
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Date published: March 31, 2017

20 Years Researching Harmful Algal Blooms Supports Sustainable Water Supply in Wichita

Two decades of harmful algal bloom, nutrient and sediment research by the U.S. Geological Survey is helping to support Wichita’s long-term vision of a sustainable water supply into the future. Early warning indicators of harmful algal blooms have been developed for Cheney Reservoir, Kansas, according to a new USGS publication done in cooperation with the City of Wichita, Kansas.

Date published: April 13, 2015

Coal-Tar-Sealant Runoff Causes Toxicity and DNA Damage

Runoff from pavement with coal-tar-based sealant is toxic to aquatic life, damages DNA, and impairs DNA repair, according to two studies by the U.S. Geological Survey published in the journals Environmental Science and Technology and Science of the Total Environment.

Date published: June 16, 2014

Well-Water for 80,000 New Hampshire Residents May contain Metals Exceeding Human Health Standards

Nearly three-in-ten well-water samples tested from southeast New Hampshire contained metals at concentrations that exceeded U.S. Environmental Protection Agency drinking-water standards and guidelines, according to a recent U.S. Geological Survey study.

Date published: April 29, 2014

Potentially Harmful Levels of Contaminants Found in Fish in the Columbia River

A newly published scientific study discovered that some resident fish in the lower Columbia River, namely largescale suckers, contain chemicals that health officials have determined can cause health concerns for people who eat large quantities of the fish.

Date published: September 4, 2013

Disinfection of Energy Wastewater Can Lead to Toxic Byproducts

Wastewater treatment plants that process waters from oil and gas development were found to discharge elevated levels of toxic chemicals known as brominated disinfection byproducts, according to a new study by the U.S. Geological Survey.

Date published: June 17, 2009

Beach Health: Safe to Swim?

When a local beach closes for health reasons, people start wondering, "Is it safe to swim?" U.S. Geological Survey (USGS) science can help local beach managers understand the sources of contamination and the kinds of contaminants that may affect human health.

Date published: October 28, 1999

Compounds in Most Groundwater Do Not Exceed Water Standards

Ground water used for drinking water generally does not contain levels of volatile organic compounds (VOCs) in excess of drinking water criteria, according to a national assessment by the U.S. Geological Survey.

Date published: June 28, 1999

Many Contaminants Found In Nation’s Streams, But Few Drinking-Water Standards Exceeded, USGS Report Shows

In a look at water-quality conditions of 20 of the country’s largest and most important river basins, the U.S. Geological Survey announced today (June 28, 1999) that streams in areas with significant agricultural or urban development almost always contain complex mixtures of nutrients and pesticides.

Date published: August 15, 1997

Chesapeake Bay Advisory: Water From Pocomoke River Will Be Tested For Toxics

The U.S. Geological Survey (USGS) is working with scientists from George Mason University and the Maryland Department of Natural Resources to collect a water sample from the Pocomoke River and analyze the sample for a variety of commonly used pesticides.

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Image: Testing Coal-Tar Sealcoats for Toxic PAH Emissions
August 23, 2011

Testing Coal-Tar Sealcoats for Toxic PAH Emissions

A USGS scientist adjusts an air pump used to measure emission of polycyclic aromatic carbons (PAHs) into the air.

USGS CoreCast
June 29, 2010

Slimy Summer Swimming: Harmful Algal Blooms in Lakes, Rivers and Streams

You may notice a green, red or brown film on your favorite boating or swimming area in the summer. This coloring could mean that the water is affected by harmful algal blooms. USGS scientists Dr. Barry Rosen, Dr. Jennifer Graham and Dr. Keith Loftin discuss why these blooms can be harmful to people, animals, and ecosystems, as well as what the USGS is doing to better

May 23, 2006

rare earth oxides

These rare-earth oxides are used as tracers to determine which parts of a watershed are eroding. Clockwise from top center: praseodymium, cerium, lanthanum, neodymium, samarium, and gadolinium. Image Number D1115-1. Photo by Peggy Greb, USDA-ARS.

Image: Harmful Algal Blooms

Harmful Algal Blooms

You may notice a green, red or brown film on your favorite boating or swimming area in the summer. This coloring could mean that the water is affected by harmful algal blooms. Harmful algal blooms are an accumulation of tiny organisms known as algae and can release harmful toxins into the environment. Pictured is Gloeotrichia echinulata, showing the entire colony under