Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


The burning issue of hydrocarbons: Impacts on human health


Highlights of Prof. Hayakawa's research who is currently developing methods to identify metabolites of PAHs and NPAHs in urine and blood. Other work include developing the most sensitive method for measuring PAHs and NPAHs, showing that motorcycle engines released more particulate matter than automobiles and more

A leading professor has spent his considerable career at Kanazawa University in Japan investigating the toxic by-products of burning fuels, and the associated impacts on human health. 

Toxic (nitro)polycyclic aromatic hydrocarbons (PAHs/NPAHs), the by-products from burning fuels such as diesel, are now known to have a significant impact on human health. Current understanding of the nature and effects of these molecules has been greatly enhanced by the work of Kazuichi Hayakawa at Kanazawa University, Japan.

Polycyclic aromatic hydrocarbons (PAHs) and their related molecules, nitropolycyclic aromatic hydrocarbons (NPAHs), are released when fuel – either fossil fuels or biomass – is burnt. They are also present following tobacco and fat combustion. PAHs and NPAHs are known to be highly carcinogenic and mutagenic, meaning they can trigger genetic mutations in living organisms. The impact of these particular molecules on human health is now being uncovered, thanks in no small part to the work of Kazuichi Hayakawa at Kanazawa University. The research is featured in the May issue of the Kanazawa University Research Bulletin:

Hayakawa is highly regarded for his development of an extremely sensitive method of determining NPAH / PAH concentrations in atmospheric particulate samples. His technique uses high performance liquid chromatography with chemiluminescence detection – separating out the chemical components of particulate matter and classifying them according to how they emit light and heat (1).

“In the 1970s, there was no analytical method for monitoring trace levels of atmospheric NPAHs, even though the toxicity of NPAHs was very strong,” explains Hayakawa. “My analytical method for determining both PAH and NPAH levels, developed over 20 years ago, remains the most sensitive technique to date.”

Hayakawa discovered that the NPAH/PAH concentration ratio in any given sample is dependent upon the original combustion temperature of the fuel. In this way, airborne particulate samples can be analyzed and the original source of the pollutants can be identified – for example burning coal, diesel or petrol. 

Between 1997 and 2002, Hayakawa led a study of airborne particulates in seven cities across East Asia2. The research revealed that, due to the higher combustion temperature, diesel engine vehicles in Japan released far more PAHs/NPAHs into the atmosphere than coal heating systems, which were predominant in China.

In 2013, novel research published by Hayakawa and his team illustrates that motorcycle engines release more particulate matter and higher levels of PAHs than automobile engines (3). The same paper shows that motorcycle particulates hold stronger PAH-related mutagenicity than emissions from other vehicles. 

As well as studying atmospheric PAHs/NPAHs over recent decades, Hayakawa has been involved in numerous investigations into the effects of these molecules on human health. His team found that NPAHs originating from diesel fuels were implicated in the development of cancerous tissues in the body (4).

Furthermore, in research published in 2003, they uncovered the role of diesel fuel PAHs in disrupting the testosterone and estrogen effects in men and women, respectively, a condition which can lead to prostate cancer and genetic reproductive disorders5.

“I am currently developing methods to identify metabolites of PAHs and NPAHs in biological samples such as urine and blood,” describes Hayakawa. “These methods will determine the risk of exposure to PAHs and NPAHs.”

Kazuichi Hayakawa’s research will continue to provide insight into environmental pollution across the globe. It will also inform the development of countermeasures that should help to reduce human health risks.

Further information:
Organization of Frontier Science and Innovation, Kanazawa University
Kakuma, Kanazawa, Ishikawa 920-1192, Japan


About Kanazawa University

Kanazawa University, Japan publishes the May 2014 issue of its online newsletter, Kanazawa University Research Bulletin:

Kanazawa University Research Bulletin highlights the latest research from one of Japan's leading comprehensive universities with its three colleges and 16 schools offering courses in subjects that include medicine, computer engineering, and humanities.

As the leading comprehensive university on the Sea of Japan coast, Kanazawa University has contributed greatly to higher education and academic research in Japan since it was founded in 1949. The University has three colleges and 16 schools offering courses in subjects that include medicine, computer engineering, and humanities.

The University is located on the coast of the Sea of Japan in Kanazawa—a city rich in history and culture. The city of Kanazawa has cultivated a highly respected intellectual profile since the time of the Kaga fiefdom (1598–1867). Kanazawa University is divided into two main campuses: Kakuma and Takaramachi for its approximately 12,200 students including 500 from overseas.

Kanazawa University website:

Associated links

Journal information

1. K. Hayakawa et al. Determination of 1,3-, 1,6- and 1,8- dinitropyrenes and 1-nitropyrene in urban air by high-performance liquid chromatography using chemiluminescence detection. Environmental Science and Technology 29 (4) (1995)
2. N. Tang et al. Polycyclic aromatic hydrocarbons and nitropolycyclic aromatic hydrocarbons in urban air particulates and their relationship to emission sources in the Pan–Japan sea countries. Atmospheric Environment 39 (2005)
3. C.T. Pham et al. Polycyclic aromatic hydrocarbons and nitropolycyclic aromatic hydrocarbons in particulates emitted by motorcycles. Environmental Pollution 183 (2013)
4. M. Iwanari et al. Induction of CYP1A1, CYP1A2, and CYP1B1 mRNAs by nitropolycyclic aromatic hydrocarbons in various human tissue-derived cells: chemical-, cytochrome P450 isoform-, and cell-specific differences. Arch Toxicology 76 (2002)
5. R. Kizu et al. A role of aryl hydrocarbon receptor in the antiandrogenic effects of polycyclic aromatic hydrocarbons in LNCaP human prostate carcinoma cells. Arch Toxicology 77 (2003)

Kanazawa University
*corresponding author, e-mail address:

Adarsh Sandhu | Research SEA News
Further information:

Further reports about: Frontier Impacts Kanazawa PAH PAHs Polycyclic aromatic combustion fuels hydrocarbons levels

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Space observation with radar to secure Germany's space infrastructure

Satellites in near-Earth orbit are at risk due to the steady increase in space debris. But their mission in the areas of telecommunications, navigation or weather forecasts is essential for society. Fraunhofer FHR therefore develops radar-based systems which allow the detection, tracking and cataloging of even the smallest particles of debris. Satellite operators who have access to our data are in a better position to plan evasive maneuvers and prevent destructive collisions. From April, 25-29 2018, Fraunhofer FHR and its partners will exhibit the complementary radar systems TIRA and GESTRA as well as the latest radar techniques for space observation across three stands at the ILA Berlin.

The "traffic situation" in space is very tense: the Earth is currently being orbited not only by countless satellites but also by a large volume of space...

Im Focus: Researchers Discover New Anti-Cancer Protein

An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.

The incidence of liver cancer, also known as hepatocellular carcinoma, is steadily increasing. In the last twenty years, the number of cases has almost doubled...

Im Focus: Researchers at Fraunhofer monitor re-entry of Chinese space station Tiangong-1

In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.

Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...

Im Focus: Alliance „OLED Licht Forum“ – Key partner for OLED lighting solutions

Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.

They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...

Im Focus: Mars' oceans formed early, possibly aided by massive volcanic eruptions

Oceans formed before Tharsis and evolved together, shaping climate history of Mars

A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

New solar solutions for sustainable buildings and cities

23.03.2018 | Event News

Virtual reality conference comes to Reutlingen

19.03.2018 | Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

Latest News

For graphite pellets, just add elbow grease

23.03.2018 | Materials Sciences

Unique communication strategy discovered in stem cell pathway controlling plant growth

23.03.2018 | Agricultural and Forestry Science

Sharpening the X-ray view of the nanocosm

23.03.2018 | Physics and Astronomy

Science & Research
Overview of more VideoLinks >>>