Cars, Trucks, Air Pollution and Health

The explosion of a a deep sea oil rig in the Gulf of Mexico is a reminder that gas and diesel consumers are partners in causing environmental degradation and disasters.
Mục lục

Driving a car or a truck is the most air polluting act an average citizen commits. Air pollution is not a good idea for a variety of reasons, large and small. The right ideas for remediation of environmental degradations involve unselfish and compassionate behavior, a scarce commodity. The right ideas involve long-term planning, conservation and a deep commitment to preserving the natural world. Without a healthy natural environment, there will be few or no healthy humans.

To understand air pollution you can consider a simple schematic that divides a big problem into components.

1. Local effects -e.g. poisoning humans breathing bad air.

2. Regional effects - fallout from airborne pathogens - infections, particles, chemicals.

3. Global effects - changing interactions between the atmosphere, oceans and the sun, weather effects, effects on plants and the ocean biosphere.

Developments in the media made "go green" the slogan for action to limit the adverse effects of air pollution. Green refers to the color of chlorophyll in plants. Chlorophyll is the basis of photosynthesis that allows plants to turn the sun's energy into life energy. Human action destroys plants and replaces healthy ecosystems with concrete and asphalt. Another slogan that emerged was "save planet earth." Humans will not save the planet. The task for humans is to stop destroying the environments that sustain themselves. If we fail, the planet will do just fine without humans.

The deepest problem for humans is that we cannot predict the future with any accuracy. Even the best informed scientist with the most recent data cannot know what is going to happen next. When we talk about prudence, we refer to methods of minimizing risk and preparing to deal with events beyond our control which can injure or kill us. Recovery from extreme weather events, earthquakes, natural catastrophes, injury and disease will consume an increasingly large chunk of our resources. Smart humans notice adverse changes and take action to minimize adverse consequences. But not all human are smart or prudent.

The year 2008 will be remembered as the near-collapse of capitalist economies. Among the corporations in trouble in the US and Canada were General Motors and Chrysler. All the US/Canada car and truck manufacturers had promoted their larger vehicles on customers by exploiting the innate human tendency to seek domination over others. Bigger is better. In 2009 the GM and Chrysler refurbished their operations and offered smaller, more fuel efficient vehicles for sale. Ford appeared to be unscathed by the recession. US car and truck manufacturers continue to build very large vehicles (e.g. pickup trucks) for the domestic market.

The explosion of a a deep sea oil rig in the Gulf of Mexico is a reminder that gas and diesel consumers are partners in causing environmental degradation and disasters. While BP gets most of the blame, two US companies who built and operated the oil rig actually caused the problem. Among the most angry BP critics are consumers of BP products. Surely the blame should be widely distributed and must include the consumers of petroleum products.

The only certainty is that the future should look very different from the past. When we consider air pollution in cities from burning fossil fuels as the main source of energy for electricity production, transportation, home heating and industrial production, then the entire infrastructure of industrial countries must change.

When cars and trucks are the focus, manufacturers are the chosen culprits, but the people who buy and drive vehicles are really responsible for creating a better future for themselves and their children. The immediate challenge for vehicle users is not to replace existing vehicles with more fuel efficient versions, but to reduce use and participate in a new vision of car-free living environments. Citizens and not governments must end the madness of traffic, gridlock, superhighways, smog and lethal accidents.

Friendly or Lethal? Cars have two opposite personalities. One is friendly and attractive the other is destructive and can be lethal. The desire to own a car is linked to pleasure, sexuality, convenience and freedom. Men lust for big, prestigious cars they way they lust for women and women desire men with big, prestigious cars. Men are also interested in power, performance and want to know something about the engine, although modern engines are sufficiently complex to discourage even the professional mechanic. Some of the engine complexity involves electronic monitoring and adjustment of engine performance under different operating conditions. Several devices are added to the engine to handle air flow in, fuel delivery and exhaust out. Computers have been added to monitor and control engine, brake and transmission operation. The design of new hybrid vehicles involves even more complexity with electronic sensors feeding data to computers that manage every system. The cost of repairs will increase as will the demand for new sophistication from mechanics. The most advanced designs use only black box modules that cannot be repaired at the local garage but can be replaced with new or rebuild modules. This might be a wonderful solution, but only if you can afford it.

Extravagant Car Use Emissions from passenger vehicles increased in Canada and the US despite attempts to make engines more fuel efficient and despite the addition of antipollution devices. The two main reasons were: 1. vehicle use increased; 2. in the US and Canada, cars got bigger; pick-up trucks, vans and sports vehicles often replaced smaller, lighter passenger cars. An average new vehicle in 2003 consumed more fuel that its counterpart in 1988. In the USA in 1987 cars averaged 25.9 miles to the gallon. Fuel efficiency dropped to 24.6 miles/gallon by 1998 and it dropped further as larger vehicles replace smaller ones. The decision to drive cars long distances to work was common among people in North America and Europe in the past 60 years. In retrospect, it is clear that commuters made a mistake. They should now stop commuting by cars. Their mistake had health and economic consequences for them personally and for every other inhabitant of planet earth.

Despite compelling evidence of climate change, governments in many affluent countries have avoided their responsibility to reduce emissions of greenhouse gases. The USA is the biggest emitter of greenhouse gases worldwide. US emissions increased to 7 billion tones of CO2 in 2004, 16% higher than emissions in the late 90's. The UK did better reducing their emissions to about 0.6 billion tons, 14% below 1990 levels. An accurate analysis of total greenhouse gas emission is difficult or impossible to achieve since there many variable and unknowns. Take the US estimates, for example, and pursue the argument that the US is also responsible for some emissions from other countries, which provide raw materials and manufacturing for the US economy. Romm argued: businesses have off-shored more and more of the U.S. economy’s and CO2 emissions to parts of the world where the carbon intensity is higher but labor is cheaper. The U.S. has essentially off-shored its emission problem to the rest of the world, turning their economies into dumping grounds for our own air pollution.

Car exhaust is toxic at ground level Exhaust from all combustion engines combine to produce local adverse effects on the health of car users and all innocent bystanders. Cities have become islands of toxic chemicals from the unrestrained use of vehicles burning fossil fuels. Cars are noisy, ugly, often dangerous and dominate the experience of modern living. We are now used to the carnage on roads and highways- attempts to reduce death and disability from our motorized containers have not substantially altered the negative impact on society. The adverse health effects of car exhaust are pervasive and difficult to measure. 

Advertising and Delusions Television Ads for sports and recreation vehicles show solitary, impeccable machines in wilderness locations. One TV ad shows a couple making a mad dash to escape the city core in their expensive, luxury upholstered clone of the land-rover. The ads are selling a fantasy of wilderness, fresh air and escape. Is the consumer is completely deluded? These vehicles are mostly found in suburban driveways and in the traffic jams of polluted cities. They have nowhere to go to escape the environmental degradation they help to create: 4x4 drives and large tires are rarely useful in cities and are not suited to highway driving. You see these machines, submerged in suburban driveways by the floods they helped to create. The latest car advertising has switched to styling, crash protection, interior comforts and fuel efficiency as selling points. While these improvements are welcome, reduced vehicle use is the most essential remedy and is seldom mentioned.

Ethanol Combustion engines contribute to greenhouse gas accumulation in the atmosphere and are responsible for climate changes. A sane, sober revision of vehicle use is long overdue. While ethanol has been championed as an alternative to petroleum fuels, it mainly helps to reduce dependency on oil producing countries. The promised ethanol revolution has not occurred and probably will never become and important fuel. Ethanol or methanol can be blended with gasoline to reduce petroleum dependency. Gasoline engines can use up to 10% ethanol without modification. New "flex" engines can use higher percentages of ethanol up to 100%. North American and European flex-fuel vehicles are optimized to run on a maximum blend of 15% gasoline with 85% ethanol (E85 fuel). The production of flex engine vehicles has increased, but the supply of flex fuel is limited. There are problems in the bigger picture of carbon consumption and emission. When ethanol is made from corn, some its energy value (up to 70% in the least efficient plants) must be spent on its production. While innovations in production technologies continue, there will be an ongoing requirement to invent new methods of production. Investment in new technologies will require government policy changes, subsidies and research grants. Climate change with extreme weather events may reduce corn production in the US, where for decades corn surpluses were common. The new competition between ethanol plants and food production suddenly in 2008 became an international issue.

Other non-food vegetable sources of carbon will become alternative sources of raw materials.

Hydrogen The ultimate cars burn hydrogen in fuel cells, but despite working prototypes, a hydrogen fuel infrastructure is a distant fantasy. One problem is the low energy density of liquefied hydrogen that requires larger tanks than the equivalent gasoline tank. Another problem is that producing hydrogen requires a large amount of energy. In Canada, there are opportunities to dam more rivers and produce electricity with falling water, a non polluting, renewable energy resource. A science fiction fantasy might include a novel way of splitting water into hydrogen and oxygen with less energy consumed but no-one has invented a novel solution. Even if new non-polluting energy sources are developed, hydrogen storage and distribution requires investment in a very expensive infrastructure.

An innovative use of hydrogen added in small quantities to gasoline and diesel engines-has been achieved by the h2gogo HRN3 Hydrogen Generator The generator produces hydrogen from distilled water and is retro-fitted to regular engines. The hydrogen input results in more efficient fuel burn, in reduced emissions and improved engine efficiency and power output. The Heathrow Airport in England retrofitted hydrogen generator units to a range of vehicles and reported up to 40% reduction in carbon dioxide, particulates, nitrogen oxides and hydrocarbon emissions.

Electric Cars are on the road, under development and promise to become vehicles of choice for urban transportation. Tesla is the best known electric car company that is addressing the need for local battery manufacturing and is building charging stations that are essential for long distance travel in their cars. The new cars represent advances in technology that link computers, electric motors and batteries into systems that drive well, self-regulate, and require little maintenance. The main components are modules that are removed to be refurbished in specialized factories and recycled. One limitation is battery technology. Batteries are heavy, wear out quickly with repeated recharging and require expensive, rather scarce materials such as lithium. Another more severe limitation is obtaining electricity from a non-polluting power source. Even if all the technical problems of building reliable electric cars were solved, there remains a daunting list of infrastructure problems yet to be solved. While electric cars produce little air pollution, generating electricity continues to be a major source of air pollution. If an electric car is recharged with electricity produced by a coal-burning generator, there may be no net benefit to the atmosphere. A real solution for car technology would reduce air pollution beginning at source materials and would continue through the use cycle of the vehicle. While is it feasible to use fossil fuels in generation plants with all the latest techniques of emission control and C02 recycling, these plants are uncommon . Before more people plug in electric vehicles, a new infrastructure of non-polluting, affordable electricity production will have to be built.

Understanding Complex Ecosystems Our ability to monitor and understand the atmosphere has taken a quantum leap in recent years. We have gone beyond naïve linear models and now appreciate that if complex systems such as the atmosphere, the oceans, and land ecosystems change, they may become unstable and more unfriendly. Extra heat will cause more turbulence, and weather patterns will change in unpredictable ways. While climate models are interesting, they have have limited to no predictive abilities. Rather than playing with unreliable, long-term predictions, a sober assessment of what is happening right now should motivate action to change human behavior. Actions, such as driving cars whenever and wherever we please, do pollute the air, change the atmosphere and cause more extreme weather events. Smart humans notice adverse changes and take action to minimize adverse consequences. But not all human are smart or prudent.

What Can I do? Drive Less Both local and global pollution would be reduced if each car-driving person pledged to use their car 30% less starting immediately. This is a responsible, individual contribution to a global problem. At least 30% of vehicle use is optional - either recreational or lazy driving when walking, cycling or public transit would be a better choice.

Cities can reduce vehicular traffic by more than 30% over the next 3 to 5 years by improving public transportation. Commuter trains are a model of urban access for suburban residents who drive their cars short distances, park in terminal lots and ride the train into town. Cities can create car free zones and develop park-like corridors that would allow movement through the city by walking, cycling and limited use of small, light electric vehicles in vehicle corridors specially designed to be safe and efficient.

The rising cost of crude oil is altering driving habits and big auto companies closed plants that produced SUVs and pickup trucks. If you are interested in longer term human survival, then high cost oil is a real benefit. With or without higher fuel prices, each person can drive less and resist the temptation to buy larger, heavier cars, trucks and sports vehicles. If you really need a 4x4 to drive off-roads in wilderness settings, you need a rugged clunker that's already got scratches, dents and mud on the tires. Carry a shovel, axe, chain saw, and a come-along in the back. If you can afford it, add a heavy duty winch up front. Stay off city streets and highways.

Solutions: Reduce Air Pollution by changing the design and use of motor vehicles

The use of cars must be re-defined. Car use has to be considered a privilege, not a right. The cost of environmental damage and reclamation has to be added to the cost of owning and operating a car. Vehicle use should no longer be subsidized.

Reduce number of Vehicles - Urban areas need to set vehicular quotas and issue permits to limit the number of vehicles to control regional traffic congestion and air pollution.

Small hybrid or 100% electric cars are desirable, but make their occupants specially vulnerable when they collide with much larger vehicles. A sane city would separate small, efficient passenger vehicles from buses and trucks.

Improve efficiency of vehicles - reverse the trend to larger vehicles; engineering solutions to emissions of combustion engines. Flex fuel and hybrid cars are a step in the right direction but in small numbers will not have a significant impact on air pollution.

Reduced vehicle use and traffic reform can be a bigger and more immediate remedy for urban air pollution. Improved efficiency of traffic is important. Examples are: dedicated bus lanes and priority for car-pools and vehicles with 3 or more passengers. Traffic can be scheduled to optimize road usage; e.g. commercial traffic at night; large companies can stagger working hours and decentralize administrative operations. Commuting long distances in cars to work needs to be phased out. Single passenger commuting to work should be strongly discouraged.

The most accessible measure of air pollution contribution is the amount of fossil fuel burned

Recreational driving can be reduced immediately. Car owners need to pay for miles driven and fuel burned on an escalating scale. Each person can have a "free driving" allotment per year and pay increasing insurance and/or taxes on fuel consumption beyond this limit.

Governments can encourage the reduction of vehicular use by

Promoting Voluntary abstention.

Increase Public Transit - diversify options and limit access to existing roads.

Separate commercial and private traffic to increase efficient use of roads.

Stop building car-oriented roads and highways.

Replace 30% of the existing roads designed for cars with park-like corridors.

In cities, build more walking paths, bicycle routes and roads for small electric vehicles.

Reduce commuting - link residence and business activities by rezoning and rebuilding cities.

Reward car-pools and car-sharing plans.

Redefine road use by defining access privileges - no longer a right.

Road Tolls and increased gasoline and vehicle registration taxes.

Base car license fees on fuel consumption in the previous year. Use exponential fee rate increase for high fuel consumption individuals.

Provide generous development grants and tax incentives for all non-polluting transportation alternatives.

Governments can use a combination of

Voluntary and Reward Schemes

Compulsory and Penalty Schemes

Incentives for New Technology and Changes in Industrial Fuel Consumption

Long term solutions require that vehicles use less polluting energy sources such biofuels, propane and natural gas. I am sorry to say that the marketing of "green solutions" to global warming is becoming yet another scam. One problem is that producing alternate fuels and hybrid cars often requires CO2 emissions that offset or cancel the benefits of improve vehicular design.

You might imagine new residential and commercial buildings that conserve energy and generate their own electricity with solar panels and wind generators that also charge their own electric vehicles. The cost of constructing new, more autonomous buildings is so great that only the wealthiest citizens can afford the capital costs.

In the immediate future reduced car use is the best solution. A gas-inefficient clunker driven twice a week for 20 km is a better choice than a new expensive hybrid car driven everyday for 100 Km. No solution is better than fewer vehicles and reduced vehicle use.

Limited Funds for Change

With once rich countries such as the USA on the verge of bankruptcy and facing the extensive repairs of already aging, derelict infrastructures, adding new, unprecedented development costs seems unlikely. Unless, of course the priorities in many countries shift dramatically. The US, for example, could adopt a sane, smart strategy, reduce its military budget by >50% and invest the money and skills in rebuilding the country's infrastructure with new sustainable energy sources.

Discussions of Environmental Science and Human Ecology were developed by Environmed Research Inc. Sechelt, B.C. Canada. Online Topics were developed from the book, Air and Breathing. This book helps you understand air quality issues, normal breathing and the causes of breathing disorders. You will find detailed information about the atmosphere, air pollution, climate change, airborne infection, air quality and airborne hazards at home.

Not all respiratory diseases are caused by airborne pathogens. If asthma, bronchitis and/or nose sinus congestion is chronic or attacks occur frequently in all seasons and are not related to airborne exposure, then consider delayed pattern food allergy as the cause and do diet revision using the Alpha Nutrition Program.

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