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Car exhaust chemicals
Chemicals in car exhaust
Car exhaust is a source of carbon dioxide and this component tends to get most of the coverage these days, but there's a whole bunch of nasty toxic chemicals in car exhaust that damage our environment. Let's take a look at a few.
Carbon Monoxide
Colorless, odorless, tasteless, yet highly toxic. Automobile and industrial emissions may also contribute to the greenhouse effect and global warming; it's one of the other greenhouse gases we don't usually hear much about. It occurs naturally in our atmosphere at around 0.1 ppm, but car exhaust without a catalytic converter contains 7,000 parts per million.
Nitrogen dioxide
Toxic by inhalation and can cause adverse health effects at low levels over a long period. It can contribute to acid rain and eutrophication in coastal waters.
Sulfur dioxide
Can cause pulmonary and respiratory distress and acidification of waterways.
Particulate matter
This is basically soot - it's most apparent effect is reducing visibility. It impacts on breathing and respiratory systems, damages lung tissues and causes cancer. Hundreds of thousands, if not millions of people and animals die prematurely each year due to the health effects of inhaling particulate matter.
Benzene
A carcinogen in humans, benzene is also very toxic aquatic life and can cause death in plants. It is a "precursor" component for formation of photochemical smog.
Formaldehyde
Another known carcinogen for humans, with similar effects to many animals and birds. In an aquatic environment, formaldehyde has a half life of between a day and ten days.
Polycyclic hydrocarbons
The U.S. Department of Health and Human Services states that some Polycyclic hydrocarbons may be carcinogens in humans and animals and can cause harmful effects on skin and the auto-immune system.
Some recent studies have also found car exhaust can create hydrocarbon-based free radicals which can linger indefinitely. These free radicals are believed to cause lung cancer and cardiovascular diseases. Even with the use of catalytic converters to help break down pollutants that cause smog, it may be creating conditions for the creation of these free radicals to form.
So when you reduce your car usage, take public transport or car pool, even just a bit of gentle exercise by walking to the store instead of driving, it's not just carbon dioxide you're keeping out of the atmosphere, but a lot of other environmentally damaging chemicals too. Even if you do need to drive your car regularly, by using simple gas saving strategies you can reduce your environmental impact and save a stack of cash at the same time.
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Car exhaust linked to heart disease, says expert
Scientists have linked car exhaust with higher risk of heart disease. That’s according to a study led by research toxicologist John Incardona of the Northwest Fisheries Science Center near Seattle, Washington.
John Incardona: Well, the fact is that we’re breathing an aerosolized oil spill if you’re in a big city. So that’s the main point, is that there’s this well-known link between ambient, everyday air pollution and heart disease, heart attacks, acute arrythmias.
Incardona’s research got its start from studies of the Exxon Valdez oil spill. In the lab, he tested the effects of the ringed polycyclic aromatic hydrocarbons, or PAHs, on the embryos of tropical zebrafish, a medical analog to humans.
John Incardona:We were able to make these observations by directly looking at the beating heart in a living embryo and saw that the function was disrupted by exposure to the three-ringed PAHs.
Because these PAHs have not been linked to cancer, Incardona said they’ve been ignored until now.
John Incardona: What if it really is these compounds that nobody’s looking at and there’s no regulation for them? So that’s why it matters.
We asked Incardona just how much city air pollution contributes to heart attacks.
John Incardona:That’s what we don’t know, right, because we study the fish. We’ve simply identified these compounds as toxic. It’s up to the medical community to go and look at these and ask whether or not these things are contributing to the acute effects of air pollution.
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