Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Manganese in underground drinking water is cause for concern

25.08.2017

UCR study on US Glacial Aquifer and 3 Asian countries suggests public health officials should monitor manganese as a possible public health threat

Underground drinking water sources in parts of the U.S. and three Asian countries may not be as safe as previously thought due to high levels of manganese, especially at shallow depths, according to a study led by a researcher at the University of California, Riverside. Manganese, a metal that is required by the body in tiny amounts, can be toxic at elevated levels, particularly in children.


UCR researchers have shown that the highest concentrations of manganese (Mn), which can be harmful to human health, are found at shallower depths than Arsenic (As) in underground drinking water wells. The study suggests that these contaminants should be evaluated separately to ensure the water is fit for consumption.

Credit: UC Riverside

Samantha Ying, an assistant professor of environmental sciences in UCR's College of Natural and Agricultural Sciences, led the study, which was published recently in Environmental Science & Technology.

The paper describes manganese levels that exceed World Health Organization (WHO) guidelines in groundwater wells in Bangladesh, Cambodia, China, and the Glacial Aquifer, which spans 26 states in the northern U.S. and provides drinking water to more than 41 million Americans. Of the four regions, the Glacial Aquifer had the fewest contaminated wells.

While groundwater can be contaminated with a number of heavy metals, more emphasis has been placed on assessing the levels of arsenic than manganese, although the latter also poses a threat to human health. Levels of arsenic, a known carcinogen above the WHO's guideline of 10 parts per billion (ppb), are enforced by the Environmental Protection Agency (EPA) in the U.S. and similar agencies in other countries. Although the WHO suggests a health-based limit of 400 ppb, manganese is not listed as a contaminant on the EPA's National Primary Drinking Water Regulations, and therefore the levels are not monitored or enforced.

A growing number of studies have linked abnormal manganese concentrations in the brain to neurological disorders similar to Parkinson's disease, and elevated levels in children may negatively impact neurodevelopment and cognitive performance.

In the current study, the researchers collected and analyzed chemical data from 16,000 wells in the Glacial Aquifer, the Ganges-Brahmaputra-Mehta Basin in Bangladesh, the Mekong Delta in Cambodia, and the Yangtze River Basin of China. The researchers studied the levels of arsenic and manganese at a range of depths, showing that, in general, arsenic levels increased with depth, while manganese levels decreased with depth.

When accounting for both metals at levels suggested by the WHO, the percentage of contaminated wells across all depths increased as follows:

-Glacial Aquifer (U.S): 9.3 percent contaminated when considering arsenic only; increased to 16.4 percent when considering arsenic and manganese.

-Ganges-Brahmaputra-Mehta Basin (Bangladesh): 44.5 percent contaminated when considering arsenic only; increased to 70 percent when considering arsenic and manganese.

-Mekong Delta (Cambodia): 10 percent contaminated when considering arsenic only; increased to 32 percent when considering arsenic and manganese.

-Yangtze River Basin (China): 19 percent contaminated when considering arsenic only; increased to 88 percent when considering arsenic and manganese.

Ying said omitting manganese from water monitoring protocols means public health officials are dramatically overestimating the number of safe wells in some regions.

However, while arsenic contaminated wells should be avoided completely, manganese contaminated wells can be treated inexpensively or be used for agriculture rather than drinking water.

"Providing access to safe drinking water is a global challenge that is increasing the demand for drinking water from underground sources," Ying said. "However, due to increasing knowledge on the detrimental impact of manganese on human health, particularly on children, manganese levels in these sources should be monitored more closely and governments should consider introducing manganese drinking water standards.

Ying said since the highest manganese concentrations were not found at the same depths as the highest arsenic concentrations, these contaminants can and should be evaluated separately to ensure groundwater is fit for human consumption or agricultural use.

###

The title of the paper is "Depth Stratification Leads to Distinct Zones of Manganese and Arsenic Contaminated Groundwater." In addition to Ying, UCR contributors include: Michael V. Schaefer, a postdoctoral researcher and Jun Li, an associate professor of statistics. Co-contributors include Scott Fendorf, a professor of soil biogeochemistry at Stanford University, and Alicea Cock?Esteb, program manager at Aquaya Institute.

Media Contact

Sarah Nightingale
sarah.nightingale@ucr.edu
951-827-4580

 @UCRiverside

http://www.ucr.edu 

Sarah Nightingale | EurekAlert!

Further reports about: arsenic drinking water human health manganese

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

Smallest transistor worldwide switches current with a single atom in solid electrolyte

17.08.2018 | Physics and Astronomy

Robots as Tools and Partners in Rehabilitation

17.08.2018 | Information Technology

Climate Impact Research in Hannover: Small Plants against Large Waves

17.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>