Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The trouble with cat converters

28.03.2007
The rapid adoption by the car industry of catalytic converters for petrol engines that reduce the quantities of toxic nitrogen oxides and hydrocarbon pollutants entering the atmosphere has significantly improved air quality, particularly in busy towns and cities. However, this improvement comes at a price, according to Italian scientists who have studied the metallic fallout from catalytic converters.

Claudio Botrè of the University of Rome and Alessandro Alimonti of the Italian National Institute of Health in Rome and their colleagues explain that the increasing numbers of catalytic converters on the road has led to rising environmental levels of the metals used as the catalysts in these devices - platinum, rhodium, palladium, and iridium. The team has published their detailed findings in the International Journal of Environment and Health.

The team analysed air particulate samples collected from two typically busy sites in Rome over the winter of 2004-2005. They used mass spectrometry to determine the chemical constituents of the samples. Their initial findings confirmed that vehicle exhausts, as opposed to hospital incinerators and industrial sites, are the main source of platinum and related metals in the urban environment.

The researchers also confirmed the findings of an earlier study that suggests that platinum is present in vehicular pollution at four times the level of rhodium. The environmental evaluation of iridium used in catalytic converters provides the first benchmark for this pollutant as no detailed tests have been carried out previously.

In terms of public health, the researchers then looked at the way the platinum group metals interact with the natural antioxidant, vitamin C (ascorbic acid) and with a compound occurring in every cell of our bodies as a product of metabolic processes, the reduced form of nicotinamide adenine dinucleotide (NADH). They hoped to determine whether the metals from catalytic converters that have entered the atmosphere and been adsorbed, or trapped, on pollutant particles which can be breathed in could ultimately have a detrimental effect on health.

They used an electrochemical method to investigate how the platinum group metals from their particulate samples reacted with ascorbic acid and NADH. Their preliminary findings suggest that these metals can trigger deleterious reactions that decrease the amount of these two vital biomolecules, in the in vitro tests at least. They will need to carry out further investigations to find out whether the body's natural defences could cope with the potential harm caused by these metals.

Lead pollution has received considerable attention, with lead in petrol rightly banned across the EU. However, the emerging problem of platinum metal pollution must be considered in evaluating the benefits of vehicle catalytic converters. The researchers suggest that closer monitoring of increasing levels of catalytic metals in urban pollution is a matter of urgency. Epidemiological studies of the health effects on children of these metals are under way elsewhere with metal content in urine samples providing a straightforward method of monitoring exposure levels.

Albert Ang | alfa
Further information:
http://dx.doi.org/10.1504/IJENVH.2007.012229

More articles from Ecology, The Environment and Conservation:

nachricht Waste in the water – New purification techniques for healthier aquatic ecosystems
24.07.2018 | Eberhard Karls Universität Tübingen

nachricht Plenty of habitat for bears in Europe
24.07.2018 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig

All articles from Ecology, The Environment and Conservation >>>

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 >>>