Scientists explain how ozone causes respiratory problems and premature death

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A research team from Birkbeck, University of London, Royal Holloway University and Uppsala University in Sweden, have helped explain how ozone causes severe respiratory problems and thousands of cases of premature death each year by attacking the fatty lining of our lungs.

In a study published in Langmuir, the team used neutrons from the Institut Laue-Langevin in Grenoble and the UK's ISIS Neutron Source to observe how even a relatively low dose of ozone attacks lipid molecules that line the lung's surface. The presence of the lipid molecules is crucial for the exchange of oxygen and carbon dioxide, as they prevent the wet surfaces of the lung from collapsing.

Ozone is mostly produced in the upper atmosphere as the sun's UV light splits oxygen molecules, but it can also form at ground level from burning fossil fuels. It is known to harm our respiratory systems and is linked to asthma, bronchitis, heart attacks, and other cardiopulmonary problems. A recent study published by the Bloomberg School's Department of Environmental Health Sciences found that stricter ozone emission regulations in the US could prevent over a thousand premature deaths and over a million complaints of respiratory problems each year [1].

However, it remains unclear how exactly ozone causes this damage. One theory is it attacks the lung's surface layers which consist of a layer of water sitting below a mixture of fatty molecules called lipids and proteins that are together known as lung surfactant. The surfactant aids the exchange of oxygen and carbon dioxide during breathing. It does this by reducing surface tension, i.e. the attraction that molecules feel for each other, in the liquid surface layer above, causing these fluids to spread out and provide a greater surface area for gas exchange.

Critically, a lack of adequate surfactant, a deficiency often found naturally in babies born prematurely, can produce similar respiratory health complaints to those mentioned above, even resulting in death in some cases.

This link was further established in 2011 by the same team from Birkbeck who demonstrated that ozone reacted very strongly with the lipid layer, damaging it. However, what exactly is going on and how these reactions might impede the surfactant from doing its job was still unclear.

To investigate further Dr Katherine Thompson from Birkbeck and her team ran neutron reflection studies at the Institut Laue-Langevin in Grenoble and ISIS Neutron Source in Oxfordshire on an artificial lipid monolayer, created to mimic the lung surface. The lipid layer was exposed to a dilute gaseous mixture of ozone, and changes in its structure or surface tension were studied in real time. The concentration of ozone was around 100 parts per billion (0.1 ppm), equivalent to what you might get in a polluted city in the summer.

The use of neutrons meant that Dr Thompson could label different parts of the sample using deuteration, a process whereby a heavier isotope of hydrogen, deuterium, is introduced and contrasted with undeuterated samples to pick out the location of hydrogen atoms. This allowed them to monitor different parts of the molecule separately as they reacted with the ozone.

Using this technique Dr Thompson's team showed that one of the lipid's upwards-facing tails, known as the C9 portion, breaks off during the ozone degradation and is lost from the surface completely. The portion still attached to the lipid head then re-orientates itself and penetrates into the air‐water interface. The loss of the C9 portion causes an initial decrease in surface tension which temporarily increases surface area for gas exchange and efficient respiration. However this effect is short-lived as the penetration of the rest of the molecule into the water results in a slow but pronounced rise in surface tension, producing an overall net increase.

The next step for Katherine and her colleagues is to look at adapting the model, to represent the condition of people with various forms of chronic respiratory problem and attempt to understand why ozone seems to affect them worse than others.

Dr Katherine Thompson, Birkbeck, University of London said: "We are not completely sure what causes the second stage of tension increase. The damaged lipid might be slowly dissolving in the water and leaving the interface entirely, or a slow reaction might be occurring that is damaging another part of the lipid not directly attacked by ozone. What we can say is that the slow increase in surface tension that occurs as a result of the ozone exposure would certainly damage the ability of our lungs to process oxygen and carbon dioxide, and could account for the respiratory problems associated with ozone poisoning."

Dr Martin King from Royal Holloway University said: "This important study shows how a key air pollutant has a detrimental effect on the human lung and could impair breathing. It is essential that a complex mixture of air pollutants - for example Ozone and nitrogen oxides - and the effect of inhaled particulate matter on the lung, is looked at next."

Dr Richard Campbell from the Institut Laue-Langevin said: "Neutrons are an ideal tool for studying biological materials, particularly their reactions and interactions on surfaces and across interfaces. They are highly sensitive to lighter atoms such as carbon, hydrogen and oxygen that make up these organic molecules and isotopic labelling can be used to determine the structure and composition of interfacial layers. As one of the world's brightest neutron sources, the ILL has a long history of modelling important micro-scale processes that take place inside our bodies and providing ground-breaking insights that inform the next generation of treatments."

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Research ties lightning to onset of migraines; may increase in pollution

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University of Cincinnati (UC) researchers have found that lightning may affect the onset of headache and migraines.

These results, published in the online edition of the journal Cephalalgia, are the first tying lightning to headache and could help chronic sufferers more efficiently anticipate headache and migraine arrival and begin preventive treatment immediately.

Geoffrey Martin, fourth-year medical student at UC, and his father Vincent Martin, MD, professor in the division of general internal medicine, UC Health physician and headache expert, led the study which showed that there was a 31 percent increased risk of headache and 28 percent increased risk of migraine for chronic headache sufferers on days lighting struck within 25 miles of study participant's homes.

In addition, new-onset headache and migraine increased by 24 percent and 23 percent in participants.

"Many studies show conflicting findings on how weather, including elements like barometric pressure and humidity, affect the onset of headaches," Geoffrey Martin says. "However, this study very clearly shows a correlation between lightning, associated meteorological factors and headaches."

Participants who fulfilled the criteria for International Headache Society-defined migraines were recruited from sites located in Ohio and Missouri and recorded their headache activity in a daily journal for three to six months.

During this time, the location where lightning struck within 25 miles of participant's homes as well as the magnitude and polarity of lightning current was recorded.

"We used mathematical models to determine if the lightning itself was the cause of the increased frequency of headaches or whether it could be attributed to other weather factors encountered with thunderstorms," says Vincent Martin. "Our results found a 19 percent increased risk for headaches on lightning days, even after accounting for these weather factors. This suggests that lightning has its own unique effect on headache."

He says that negatively charged lightning currents were also particularly associated with a higher chance of headache.

"There are a number of ways in which lightning might trigger headaches," he says. "Electromagnetic waves emitted from lightning could trigger headaches. In addition, lightning produces increases in air pollutants like ozone and can cause release of fungal spores that might lead to migraine."

"This study gives some insight into the tie between headaches or migraines, lightning and other meteorologic factors," says Geoffrey Martin. "However, the exact mechanisms through which lightning and/or its associated meteorologic factors trigger headache are unknown, although we do have speculations. Ultimately, the effect of weather on headache is complex, and future studies will be needed to define more precisely the role of lightning and thunderstorms on headache."

Breathe Smog? Report Says You’re More Likely to Die Early.

According to a recent report released by the National Research Council of the National Academy of Sciences, people who are exposed to high levels of smog, even for as little as a day, have an increased risk of premature death.

The committee leading the research concluded that even short-term exposure to ozone can exacerbate lung conditions, causing illness and hospitalization and can potentially lead to death.

The Bush administration has resisted stricter standards on smog, and maintains there is no evidence to support this report.

Ozone is the primary ingredient of smog and is created from nitrogen oxide and organic compounds released from car engines and other fossil-fuel-burning sources. Indoor Air Quality (IAQ) Experts point to the fact that these primary ingredients of smog have long been proven to be a health risk.

“These toxins are proven to increase the risk of respiratory problems, especially in children and the elderly,” said biochemical engineer and AllerAir IAQ Expert, Karen Hand. “This fact alone is reason enough for people to be proactive about protecting their health, and the health of those that they love.”

Hand says high-quality air purifiers are providing protection to many North American families who are concerned about the effect of poor indoor air quality.

For more information on the dangerous effects of smog, or for more information on high-quality air purifiers, contact one of AllerAir’s Indoor Air Quality Expert at 1.888.852.8247 or visit their www.allerair.com website.

Knoxville, Tennessee Deemed Asthma Capital of the World; Poor Air Quality to Blame

According to a 2008 Asthma and Allergy Foundation report, Knoxville is the asthma capital of the world—- due in great measure to the poor air quality in East Tennessee. Ozone and particulate matter are the two greatest contributors to air pollution in the area.

Mark Wenzler, the director of clean air and climate programs with the National Parks Conservation Association told knoxnews.com that people should pay close attention to air-quality alerts because “even healthy people could be impacted due to ozone”.

The Indoor Air Quality Experts at AllerAir agree with Wenzler, adding: “People who seek refuge indoors, especially in places like Knoxville, where pollution is very high, often don’t realize that indoor air is often times much worse than outdoor air,” said Karen Hand, an IAQ specialist with the company. “We have many customers in East Tennessee, and our recommendation is always the same: get an air purifier for your home—- it will make a world of difference, especially to asthma sufferers.”

To speak with an Indoor Air Quality Expert at AllerAir, you can call toll free at 888 852 8247 for a no-obligation consultation.

Air Quality Health Advisory Issued for New York State

Due to high levels of ozone and high levels of particulate matter, the New York State Department of Environmental Conservation (DEC) and State Department of Health (DOH) have issued an Air Quality Health Advisory for the New York City Metro and Long Island regions of New York state for today, September 4, 2008.

Indoor Air Quality (IAQ) Experts are reminding New York state residents that indoor air is affected as well as outdoor air. Residents should use fans to circulate air, and air conditioners if necessary.

Since people spend up to 90% of our time indoors, it’s essential that the air we breathe is clean — especially when an Air Quality Health Advisory has been issued, IAQ experts say. This is especially important for children, the elderly, and those with respiratory difficulties.

Residents living in areas experiencing an Air Quality Health Advisory are invited to call 888-852-8247 to speak to an IAQ Expert to receive information on how an air purifier can remove dangerous particles and chemicals from indoor air.