Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Fertilizer chemicals linked to animal developmental woes

30.08.2010
Fertilizer chemicals may pose a bigger hazard to the environment – specifically to creatures that live in water – than originally foreseen, according to new research from North Carolina State University toxicologists.

In a study published in the Aug. 27 edition of PLoS One, the NC State researchers show that water fleas take up nitrates and nitrites – common chemicals used primarily in agriculture as fertilizers – and convert those chemicals into nitric oxide. Nitric oxide can be toxic to many organisms.

The study shows that water fleas introduced to fertilizer chemicals in water were plagued with developmental and reproductive problems consistent with nitric oxide toxicity, even at what would be considered low concentrations.

This raises questions about the effect these chemicals may have on other organisms, says Dr. Gerald LeBlanc, professor of environmental and molecular toxicology at NC State and the corresponding author of the paper describing the results. He adds that additional research will be needed to explore those questions.

LeBlanc says that some of the study's results were surprising.

"There's only limited evidence to suggest that animals could convert nitrates and nitrites to nitric oxide, although plants can," he says. "Since animals and plants don't have the same cellular machinery for this conversion, it appears animals use different machinery for this conversion to occur."

LeBlanc was also dismayed at seeing toxic effects at low chemical concentrations.

"Nitrite concentrations in water vary across the United States, but commonly fall within 1 to 2 milligrams per liter of water," he says. "We saw negative effects to water fleas at approximately 0.3 milligrams per liter of water."

Harmful effects of nitric oxide included developmental delay – water flea babies were born on schedule but were underdeveloped; some lacked appendages important for swimming, for instance.

LeBlanc now plans to identify the mechanism behind nitric oxide's toxic effects; evaluate the relationship between nitrite and nitrate concentrations in the environment and developmental toxicity; and consider possible risks to humans.

"It's not possible to eliminate nitrates and nitrites from our lives – they do wonders in agricultural crop production," LeBlanc says. "But we can take measures to ensure that the benefits of these chemicals outweigh their risks by keeping them out of surface waters."

The research was funded by the Environmental Protection Agency and the National Science Foundation.

The Department of Environmental and Molecular Toxicology is part of the university's College of Agriculture and Life Sciences.

Note to editors: An abstract of the paper follows.

"Intracellular Conversion of Environmental Nitrate and Nitrite to Nitric Oxide With Resulting Developmental Toxicity"
Authors: Bethany R. Hannas, Parikshit C. Das, Hong Li and Gerald A. LeBlanc, North Carolina State University

Published: Aug. 27, 2010, in PLoS One

Abstract: Nitrate and nitrite (jointly referred to herein as NOx) are ubiquitous environmental contaminants to which aquatic organisms are at particularly high risk of exposure. We tested the hypothesis that NOx undergo intracellular conversion to the potent signaling molecule nitric oxide resulting in the disruption of endocrine-regulated processes. These experiments were performed with insect cells (Drosophila S2) and whole organisms Daphnia magna. We first evaluated the ability of cells to convert nitrate (NO3) and nitrite (NO2) to nitric oxide using amperometric real-time nitric oxide detection. Both NO3 and NO2 were converted to nitric oxide in a substrate concentration-dependent manner. Further, nitric oxide trapping and fluorescent visualization studies revealed that perinatal daphnids readily convert NO2 to nitric oxide. Next, daphnids were continuously exposed to concentrations of the nitric oxide-donor sodium bitroprusside (positive control) and to concentrations of NO3 and NO2. All three compounds interfered with normal embryo development and reduced daphnid fecundity. Developmental abnormalities were characteristic of those elicited by compounds that interfere with ecdysteriod signaling. However, no compelling evidence was generated to indicate that nitric oxide reduced ecdysteriod titers. Results demonstrate that nitrite elicits developmental and reproductive toxicity at environmentally relevant concentrations due likely to its intracellular conversion to nitric oxide.

Dr. Gerald LeBlanc | EurekAlert!
Further information:
http://www.ncsu.edu

More articles from Life Sciences:

nachricht During HIV infection, antibody can block B cells from fighting pathogens
14.08.2018 | NIH/National Institute of Allergy and Infectious Diseases

nachricht First study on physical properties of giant cancer cells may inform new treatments
14.08.2018 | Brown University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

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...

Im Focus: Lining up surprising behaviors of superconductor with one of the world's strongest magnets

Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur

What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...

Im Focus: World record: Fastest 3-D tomographic images at BESSY II

The quality of materials often depends on the manufacturing process. In casting and welding, for example, the rate at which melts solidify and the resulting microstructure of the alloy is important. With metallic foams as well, it depends on exactly how the foaming process takes place. To understand these processes fully requires fast sensing capability. The fastest 3D tomographic images to date have now been achieved at the BESSY II X-ray source operated by the Helmholtz-Zentrum Berlin.

Dr. Francisco Garcia-Moreno and his team have designed a turntable that rotates ultra-stably about its axis at a constant rotational speed. This really depends...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
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

2018 Work Research Conference

25.07.2018 | Event News

 
Latest News

'Building up' stretchable electronics to be as multipurpose as your smartphone

14.08.2018 | Information Technology

During HIV infection, antibody can block B cells from fighting pathogens

14.08.2018 | Life Sciences

First study on physical properties of giant cancer cells may inform new treatments

14.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>