Monday, December 26, 2011

Happy New Year!

English: Wikipedia Happy New YearImage via Wikipedia

Taking a week off to recharge the batteries.

New posts will begin again on January 3, 2012

Best wishes to all for a healthy and happy New Year!
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Friday, December 23, 2011

Planning the Ideal Town

Planning the Perfect Place - From Scratch (Tim Halbur, Planetizen, Nov. 28, 2011)

Claude Lewenz on VillageTowns (6 min video)

How would you design a town if you started from scratch? This is the question and challenge that faced Claude Lewenz after he decided that his native USA was not ready and decided to go to New Zealand to live. Today we review an interview that Tim Halbur had with Mr. Lewenz which highlights some of his guiding principles to create a sustainable community in both economic and social respects. This starts with the intelligent design of small self-sustaining communities.

Key Quotes:

"what would happen if we use architecture and design so that the problems didn’t grow, and eventually died out? That we actually use design rather than rules or rather than taxpayers' money or all this nonsense"

"enable people and communities to provide for their social, economic, and cultural well-being while protecting and persevering the environment and the life giving forces of earth, water, sky, and ecosystems for now and for the foreseeable needs of future generations." [stated purpose of New Zealand’s resource management act)

“when a community gets over 150 people, people don't know each other anymore…if you have a community of 1,200 people you can only support one general store there…You need 5-10,000 people to have a local economy. That's where this concept of village-town came from”

"when several villages come together to become self-supporting, the purpose of their continuance is to enable their people, their citizens, to enjoy a good life"

“I’m a big fan of cafe, tavern, "taberna" type lifestyle where, especially in Eurppe you go to a place and the food’s inexpensive, fantastic tasting, and it isn’t like going out to dine, where you have to spend $100 and can't do that very often”
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Thursday, December 22, 2011

Freeways: divide and pollute cities today - greenspace tomorrow?

Junctions and ramps connecting I-80 and I-480 ...Image via WikipediaAre freeways doomed? -Several cities are tearing down highways, creating bold new public spaces -- and building a future without cars (Dream City, Nov. 30, 2011)

Also discussed here: Carmageddon - Complete coverage of the 405 freeway closure during July 16-18 (Los Angeles Times, Aug. 2, 2011)
Video: A time-lapse of the Mulholland Drive bridge demolition

A number of cities in the USA have seen the light and replaced expensive, ineffective, polluting freeways that divide communities with parks and tourist vistas that unite them. The article under review today summarizes the situation across the country in recent days from New jersey to San Francisco to New York to Minneapolis. Soon many more will reap the benefits and quality of life that freewayless cities such as Vancouver BC have enjoyed for years.

Bottom line “Improved traffic flow, fewer roads to maintain, nicer neighborhoods — what’s not to love?”

Key Quotes:

“The drive to tear down the huge freeways that many blame for the inner-city blight of the ’60s and ’70s is one of the most dramatic signs of the new urban order”

“For some cities, this means a once-in-a-lifetime opportunity to reclaim a vast amount of downtown land and turn it into the public space of their dreams”
  • “Trenton, N.J….is looking at converting the four-lane highway that runs along the Delaware River into a vibrant waterfront of parks and buildings”
  • “as New Orleans implements a new master plan for the city following Hurricane Katrina, anything seems possible — including a pitch to tear down the Claiborne Expressway, the freeway that divided several of the city’s historically black neighborhoods when it was erected decades ago.. It would also reunite the neighborhoods the freeway divided, allowing residents of the north side to benefit from the south side’s proximity to the French Quarter.”
  • “San Francisco .. demolished the bay-adjacent double-decker Embarcadero Freeway after it was damaged in an earthquake. Today, the area .. has evolved from a forbidding dead zone to a bustling waterfront and tourist magnet”
  • “New York is studying plans to tear down the Sheridan, which runs along the Bronx River”
“the dirty secret of freeways is that they don’t reduce traffic, they create it”
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Wednesday, December 21, 2011

Road Noise from Motor Vehicles in Europe

Nederlands: Geluidsscherm langs A13 bij OverschieImage via WikipediaBEVERLY HILLS, CA - OCTOBER 29:  (L-R) Chairma...Image by Getty Images via @daylifeProposal for a Regulation on the Sound Level of Motor Vehicles (12 gage pdf, Commission Staff Working Paper- Executive Summary of the Impact Assessment, Dec. 9, 2011)

Also discussed here: EU Would Quiet Vehicles to Benefit Public Health (Environment News Service, Dec. 12, 2011)

The focus today is on a new proposal to reduce by 25% the vehicle noise which impacts the health of almost 21 million citizens of European cities. Past efforts to accomplish this have little success because of the introduction of wider noiser tires, increasing urban traffic and the slow transition from noisy to more modern quieter vehicles- despite the advent of electric vehicles which are soundless (but represent less than 5% of the cars on the road) . The situation is summed up by this quote: "After air pollution, noise is the biggest environmental health problem in Europe".

Key Quotes:

“The European Commission Friday adopted a proposal to reduce the noise produced by cars, vans, buses, coaches, light and heavy trucks by some 25 percent over five years”

“European vehicle noise emissions limits have not changed since 1996, despite increasing traffic.. which negatively affects almost half of European citizens, around 210 million people”

“almost 67 million people (i.e. 55 % of the population living in agglomerations with more than 250 000 inhabitants) are exposed to daily road noise levels exceeding 55 dB.. Almost 21 million people (i.e. 17 % of the population living in urban agglomerations) live in areas where night-time road noise levels have detrimental effects on health”

“The exposure of people to traffic noise can be reduced in different ways: through reducing noise limits at the source, .. or through other indirect measures such as tax relief schemes for environmentally friendly investments ., standards for acquisition of quiet delivery vehicles … traffic restrictions.. rerouting and speed restrictions or noise abatement solutions (noise barriers, quiet road surfaces, façade insulation)”

"It's far cheaper to add readily-available noise reducing technology to vehicles than for cash-strapped local authorities to spend millions on noise barriers along roads. The benefits outweigh the costs by 20 to 1, so there is no excuse for inaction."
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Tuesday, December 20, 2011

Global Overview of Health Impacts from Particulate Matter

Premature Mortality and Particulate Matter: A Critical Challenge in Urban Management - A Global Perspective on Effects, Placed in an Asian Context (57 page pdf slides, Bob O’Keefe, Sixth Regional EST Forum in Asia, New Delhi, India, Nov. 9, 2011)

Today, we review the keynote address to The Sixth Regional EST Forum in Asia,sponsored by the World Health Organization with the Theme: Sustainable Mobility. The author provided highlights of recent research into the health impact associated with air pollution, pointing out the risks of proximity (within 300-500 m) of most urban populations to traffic.

Key Quotes:

*High levels of PM (> 500 μ/m3) known to cause premature death. Studies in US, Europe, elsewhere have found association of PM with mortality at much lower levels (<50μ/m3); No evidence of a “threshold” (safe level)”

“Estimates impact of urban outdoor air pollution worldwide:~795,000 premature deaths per year attributable to PM air pollution in Asian cities”

“• Highest exposures 300-500 meters from major roads - Growing evidence of effects, especially asthma exacerbation in children”
  • In Los Angeles, 44% of population live in the maximum zone of impact of major roads
  • in Delhi: New HEI Analysis: 55% of the Population within 500 meters of a highway; 50 meters of a major road
  • in Beijing: New HEI Analysis: 76% of the Population within 500 meters of a highway; 50 meters of a major road”
“the Panel found:
  • Sufficient evidence that exposure to traffic can cause exacerbation of asthma, especially in children
  • Suggestive evidence for other health effects (premature mortality, lung function, respiratory symptoms, and others)
  • But only limited evidence of effects for: Adult onset asthma; Health care utilization; COPD; Non-asthmatic allergy; Birth outcomes; Cancers”
“Given the large number of people living within 300- 500 meters of a major road, the Panel concluded that exposures to primary traffic generated pollutants are likely to be of public health concern and deserve attention”

“Who is most at risk from premature mortality from PM Exposure?

• Highest effects generally seen among: Older, frail members of society; Those with preexisting heart or lung disease

Highest PM effects for Heart disease (18% - 24% increase in risk per 10 μg/m3PM2.5)”
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Monday, December 19, 2011

Proximity to Traffic, Autism and Impacts on the Brain

The Hidden Toll of Traffic Jams - Scientists Increasingly Link Vehicle Exhaust With Brain-Cell Damage, Higher Rates of Autism
(Robert Lee Hotz , Wall Street Journal, Nov. 8, 2011)
Also discussed here: Autism Increase May Be Blamed On Increased Traffic Fumes (The Autism Newswire)

And here: Increased Rates of Neurocognitive Issues Linked to High Traffic Areas (Carolyn Drake, HCP Live, Nov. 30, 2011)

And here: Rush-Hour Read: The Link Between Traffic Congestion and Health (Daniel Lippman, The Infrastructurist, Nov. 9, 2011)

Today, we return to a review of studies on the health impacts on the brain for those who breathe air near traffic. The studies indicate that the while the vehicle emissions affect everyone for periods as short as 30 minutes, impacts near traffic include the intelligence and emotional stability of children and the brain activity of seniors. There is evidence also that congestion pricing’s role in improving air quality has beneficial health impacts.

Key Quotes
“New public-health studies and laboratory experiments suggest that, at every stage of life, traffic fumes exact a measurable toll on mental capacity, intelligence and emotional stability. There are more and more scientists trying to find whether and why exposure to traffic exhaust can damage the human brain

“Traffic fumes from some major L.A. freeways reached up to 1.5 miles downwind—10 times farther than previously believed”

"There are more and more scientists trying to find whether and why exposure to traffic exhaust can damage the human brain,"

“an individual breathing street-level fumes for just 30 minutes will experience more intense electrical activity in brain regions accountable for behavior, personality, and decision-making—a change that is normally an indication of stress, they stated”

“an elderly individual breathing normal city air with high levels of traffic exhaust for 90 days could suffer alterations to how his/her genes turn on or off”

“the intelligence and emotional stability of children residing in areas affected by high levels of emissions…such children scored worse on IQ tests and were more prone to depression, anxiety, and attention issues than children who lived in areas with cleaner air"

“children born to mothers who resided within 1,000 feet of a major road or freeway in Los Angeles, San Francisco, or Sacramento were twice as likely to be autistic”

“areas around highway toll plazas [in New Jersey, USA] dropped 10.8% after the introduction of E-ZPass, which eased traffic congestion and reduced exhaust fumes, according to reports published in scientific journals this year and in 2009.”
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Friday, December 16, 2011

Tolls, Congestion and HOT Lanes in Canadian Cities

FasTrak High-occupancy toll (HOT) lanes at 91 ...Image via WikipediaCongestive Traffic Failure: The Case for High-Occupancy and Express Toll Lanes in Canadian Cities (9 page pdf, Benjamin Dachis, C.D. Howe Institute, Aug. 31, 2011)

Also discussed here: Think Tank proposes HOT lanes for Vancouver, Calgary and Montreal (Road Pricing, Nov. 2, 2011)

The difficulty on introducing tolls as urban cities become more and more clogged with traffic is addressed in the report reviewed today which suggests high-occupancy toll ( HOT) lanes for Canada’s five largest cities. HOT lanes could generate more than $1 B/ year in much needed net revenue in these cities where congestion costs more than $5 Billion or $410 per capita pm average.

Key Quotes:

“Canada’s urban highways are choked with congestion because road access is free and scarce road space is occupied by drivers who wait, albeit grumpily, in traffic”

“governments have chosen to build carpool lanes on urban highways, despite evidence that these lanes have limited effectiveness in curbing congestion”

“Governments should instead convert existing and planned carpool lanes to high-occupancy toll (HOT) lanes, giving drivers a choice of whether to use them or free lanes.. improve travel time reliability, increasehighway capacity and potentially reduce congestion on un-tolled lanes”

“congestion in Vancouver cost C$927 million per annum ..which comes to C$466 per capita”

“allowing vehicles to use the network by paying a toll akin to C$0.23 per km at peak times and half that at the off peak - to match the Toronto 407 toll road rates.. would generate C$81 million per annum in revenue.”

“taxes on fuel and ownership only cover 53% of road infrastructure costs”

“The political dilemma of pricing what were previously free lanes has hitherto stymied road toll proposals. By preserving a non-toll option, HOT and express lanes provide the solution. They can achieve the benefits of road pricing, while still being politically palatable, since drivers have the choice to drive for free in adjacent lanes”
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Thursday, December 15, 2011

Making Paris Mobile in a Cleaner Environment

English: Paris, France : station Velib (bike h...

Deutsch: Paris: Eiffelturm und Marsfeld]

The greening of Paris

( Manisha Gutman, The Hindu,Feb. 3, 2008)

Also discussed here: Slowth (Eric Britton, World Streets, Mar. 9, 2009)

Paris received an award recently for its Mobility Plan which was aimed at replacing its car culture with other and less polluting forms of transportation, including innovative bicycle and car sharing schemes, extensive information communication systems making known the availability of the alternatives and improved public transit based on the concept of “slowth”, not fast and growth.

Key Quotes:

“In a dense urban context, cars are the most inefficient system of transport, creating traffic jams and needing more and more parking space. The car culture in the city had to be replaced by alternative systems of transport”

“Priorities of the New Mobility plan for Paris:
  • improving air quality and public health, with an emphasis on reducing carbon emissions.
  • mobility had to be improved not only for the rich few, but for all, overcoming barriers of physical and economic handicaps.
  • creating a beautiful city remained a priority.
  • rejuvenate economic vitality, supporting commerce and tourism.
  • regional solidarity, uniting the two million people who live within the city limits with the 12 million that live around the city, in the larger region of the Ile-de-France”
“The 20,000 Velib public cycles that were introduced in June this year [2008]were preceded by an establishment of 400 km of cycle paths in the city”

““autopartage” — public cars that can be hired successively by different users to cover different routes”

“a traffic system based on slowth is carefully calibrated to lower top speeds , but the entire system leads to far steadier flows and throughput, and, with it, greater safety, lower emissions, and higher quality of life all around”
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Wednesday, December 14, 2011

How Expensive are Roads Built only for Cars?

Combating the Myth That Complete Streets Are Too Expensive (Tanya Snyder, World Streets DC, Dec. 8, 2011)

Also discussed here: National Complete Steets Coalition

Today we look at reasons to build streets for uses other than driving (such as cycling and walking) and find that this is not only economical but also adds to the overall quality of life for cities that take this approach. Making roads more narrow for driving also reduces costs.

Key Quotes:

“Do you put on your walking boots only to find that your city’s street design conveys the message, ‘These roads were made for driving?’”

Sidewalks will turn out to be somewhere around 3 percent of that compilation of costs.. Bicycle lanes, around 5 percent — and that’s adding bicycle lanes, of course, to both sides of the street…reducing the width of a lane by a foot can reduce the costs by 2 percent.”

“In many cases, by accommodating road uses that take up less space than automobiles, cities can reduce the need for road and intersection widening later”
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Tuesday, December 13, 2011

Health Impacts from Exposure to Emissions from Traffic

English: Intermed. mag. (H&E). Image:Cardiac a...Image via Wikipedia

Health Update - Association Between Exposure to Traffic and Heart Disease (6 page pdf, Air Resources Board, California Environmental Protection Agency, Feb. 24, 2005)

Today we review a briefing to the California Air Resources Board on the health risks faced by those who travel on or live near freeways. Results “provide evidence for an association between exposure to traffic and its pollutants and increased risk of heart attacks and heart disease risk factors, even in healthy, young adults”.

Key Quotes:

“increased death from heart and lung disease - Particle counts and black carbon increase by a factor of 30 near 405 and 710 freeways”

“There was a rapid decrease in concentration on the downwind side of the freeways to near background levels within about 500 feet”

“for a typical commuter, the in-vehicle exposure to traffic-related pollutants while travelling on freeways can represent more than 50% of their daily exposure to ultrafine PM”

“German investigators focused on residents of Augsburg, a city of about 280,000 residents located near Munich, who experienced nonlethal heart attacks over a two-year period- The risk was greatest – a threefold increase – when traffic exposure occurred one hour before the heart attack”

“Nine healthy North Carolina State Troopers were monitored using real-time electrocardiographs. The volunteers were males ages 23 to 30, non-smokers, and had shifts from 3 pm to midnight- In-vehicle PM2.5 levels were associated with significant changes in markers of inflammation, blood coagulation, and cardiac rhythm, which are possible indicators for increased risk of heart disease”
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Monday, December 12, 2011

Pricing Parking Policies and Principles in Delhi, India

Districts of Delhi, with Narela in the North W...

Parking Policy for Delhi(126 slides PowerPoint file, Municipal Corporation of Delhi, Dec, 2011)

Also discussed here: Congestion charges around the world - Delhi is planning to introduce a congestion charge, following in the footsteps of Singapore, London, Oslo and Stockholm (Gwyn Topham, The Guardian, Dec. 8, 2011)

Today’s review article comes from Delhi, the 100 year old Capital of India (as of today), where the need for an improved policy toward congestion and parking is proposed to relieve congestion and the amount of space used for parking of the millions of vehicles. Options considered include pricing parking spaces by location and time of day and a congestion charge for vehicles other than public entering the urban core. Many of the policies and approaches would seem to apply to other cities.

Key Quotes:

“A car is allotted 23 sq m for parking. On an average three different car spaces are needed per car in the city, result, the current fleet occupies nearly 9-10 % of Delhi’s geographic area”

“Overall Principles:
  • Parking should be managed so that it supports the City’s strategic outcomes for economic development, urban development, transport, environmental, social and recreation, and cultural well being.
  • Parking also has the equally important role of supporting a better land transport system for the city that is integrated, safe, responsive and sustainable
  • Street space is a scarce resource and priority for use for parking needs to be considered against other uses and depends on the location, type of street, time of day and day of week
  • Revenue from parking needs to reflect the parking policy and the city’s strategic direction. Pricing is an effective tool in maintaining a certain level of availability of the on-street spaces…”
“The overarching objective for parking is to progressively reduce the demand for parking and facilitate organized parking for all types of vehicles”

“Introduction of congestion tax in select high density and business district (zones) of the city. Rationalisation of the fee in accordance with the land use and price is to be followed”

  • A variable pricing based on the location of the parking linked to land price is a desirable model: Parking in the centre of city will be costlier than parking in the periphery as the value of the land is different.
  • Variable pricing based on hourly basis during the peak hours and lower prices during the off peak periods is recommended.
  • Fee collection can be through automated methods or manual means.
  • This must be carried out within the guidelines drawn up by the authority.
  • Variable parking fee needs to be based on the size and type of vehicle – the larger the vehicle, the fee will be higher.
  • The increase of tariff for the number of hours parked will be cumulative scale with every increase of hour parked- the fee will be higher”
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Friday, December 9, 2011

Health Benefits from Mitigating Climate Change in Transportation

Health co-benefits of climate change mitigation - Transport sector (156 page pdf, Jamie Hosking, Pierpaolo Mudu, Carlos Dora, Health Impact Assessment, World health Organization, Dec., 2011)
Today the focus is on a report issued by the World Health Organization in connection with the Climate Change Conference held at Durban, South Africa. The report examines the positive impacts on health by reducing greenhouse gas emissions from transportation and the advantages and disadvantages of certain strategies such as the results of congestion pricing (positive) or the shift to diesel fuel (negative).

Key Quotes:

“This new WHO report, part of the Health in the Green Economy series, considers the evidence regarding health co-benefits, and risks, of climate change mitigation strategies for transport, as reviewed by the Intergovernmental Panel on Climate Change

“Health benefits may include: physical activity from walking and cycling, which can help prevent heart disease, some cancers, type 2 diabetes, and some obesity-related risks; lower urban air pollution concentrations; lower rates of traffic injury risks for users of dedicated bicycle and pedestrian networks; and less noise stress”

“A shift to active transport (walking and cycling) and rapid transit/public transport combined with improved land use can yield much greater immediate health “co-benefits” than improving fuel and vehicle efficiencies”

“Potential health gains of a shift from private motorized transport to walking, cycling and rapid transit/public transport include reduced cardiovascular and respiratory disease from air pollution, less traffic injury and less noise-related stress”

“Shifting from gasoline to diesel vehicles could increase emissions of health-damaging small particulates (PM10, PM2.5)”

“Transport-related health risks now cause the deaths of millions of people annually”

Congestion charges have reduced emissions by 13–30%, while a subsidy for low carbon fuel has been estimated to reduce emissions by 6%”
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Thursday, December 8, 2011

Are Pollution Hotspots Legal in Ontario?

Pollution-iconImage via WikipediaPollution, hot spots and environmental justice (Dianne Saxe, Environmental Law and Litigation, Dec. 5, 2011

Also discussed here: Pollution, Hot Spots and Environmental Justice (Dianne Saxe, Slaw, Dec. 5, 2011)

Topping the reviews today is a blog post by a lawyer who examines the potential inconsistency of environmental law, as expressed by the 1993 Ontario Environmental Bill of Rights, when applied to varying levels of air pollution across the province. Although she looked only at industrial examples (burning tires and stack emissions), the basic issue presented is whether the law could extend to differences in pollution at the neighbourhood level and, by extension in our mind, to pollution hotspots created by heavy traffic on urban public roads.

Key Quotes:

“Is it acceptable for legal pollution levels to be higher in some neighbourhoods than in others?”

“a Charter challenge … argues that Ministry of the Environment ongoing approval of multiple sources of pollution surrounding their Sarnia reserve violates their rights to life, liberty and security of the person and to equality”

“the Ontario Environmental Review Tribunal had granted neighbours of a cement manufacturing facility leave to appeal permits, issued by the Ministry of the Environment, allowing Lafarge to burn tires, as fuel, at its cement manufacturing facility…The Tribunal found there was a failure on the part of the Directors to take into account “environmental consistency”.. consistency means that facilities should be regulated as necessary to limit environmental effects to a consistent level across Ontario”

“Air and water pollution levels do vary from place to place– for example, mountains and forests typically have cleaner air than highways or industrial areas. Is it unreasonable for regulators to allow different levels of pollution in different places, and if so when? Does this contravene the preamble to Ontario’s Environmental Bill of Rights,1993, S.O. 1993, ch. 28: “The people of Ontario have a right to a healthful environment”? Or not?”
[caption id="" align="alignright" width="93" caption="Image via Wikipedia"]Pollution-icon[/caption]

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Wednesday, December 7, 2011

The Health Impact of Emissions from Light Traffic

Heavy vehicle traffic is related to wheeze among schoolchildren: a population-based study in an area with low traffic flows ( 8 page pdf, Martin Andersson, Lars Modig, Linnea Hedman, Bertil Forsbergand Eva Rönmark, Environmental Health, Oct. 13, 2011,

The review today looks at research in northern Sweden and the health impact for children within 200 m of relatively low flows of traffic (100-250 vehicles per day). The results indicate a respiratory health risk, not only for those near low traffic but also a possibility of underestimated risks near high traffic flow.

Key Quotes:

“Asthma is a major public health issue, affecting 300 million people all ages world-wide”

“The present study is one of the very few that describe an association between traffic air pollution and symptoms of asthma in children in a cold climate setting with, in a global perspective, low traffic intensity and small socio-economic differences in the population”

“Exposure to high traffic flows was uncommon in the study area; only 15% of the children lived within 200 meters from a road with a traffic flow of 8000 vehicles per day”

“The unadjusted odds ratio for current wheeze when living closer than 200 m from a road with ≥500 heavy vehicles daily was 1.8.. This association became weaker but still significant, with decreasing frequency of heavy traffic flow”

“Children having high traffic flows within 200 meters from home, are most often exposed to higher levels of gases and particles, both refereeing to long- and short term exposures”

“By using three different cut-off levels within the 200 m radius we could show the importance of larger roads (250 vehicles per day) in comparison to using a lower cut-off (100 vehicles per day)”

“vehicle traffic emissions may pose a threat to public health also in large areas of the world where background pollution and traffic intensity are low and an even larger threat to respiratory health in highly trafficked communities where the risk may be underestimated”
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Tuesday, December 6, 2011

Health Impacts from Road Traffic and Railway Noise

English: Main complications of persistent high...Image via WikipediaExposure to road traffic and railway noise and associations with blood pressure and self-reported hypertension: a cohort study ( 11 page pdf, Mette Sørensen, Martin Hvidberg, Barbara Hoffmann, Zorana J Andersen, Rikke B Nordsborg, Kenneth G Lillelund, Jørgen Jakobsen, Anne Tjønneland, Kim Overvad and Ole Raaschou-Nielsen,Environmental Health, Oct. 28, 2011)

Today we review some research from Denmark which tried to assess the impact of road traffic and railway noise on blood pressure and hypertension, after taking into account the additional impacts of air pollution. There was a weak link with both sources, although it was thought that those who were most sensitive to noise (especially seniors) may have taken medication that reduced the impacts, compared to non-medicated people.

Key Quotes:

“Exposure to noise can interfere with relaxation and concentration and during the night, noise exposure at normal urban levels has been associated with sleep disturbances”

“An overview from 2006 of the effects of exposure to transport noise (road, air and rail) on cardiovascular health concluded that transport noise is associated with hypertension, which has mostly been verified by later studies on road traffic noise”

“The few studies that have investigated effects of exposure to long-term air pollution on BP and hypertension has found air pollution to be positively associated with systolic and diastolic BP as well as with hypertension”

“The results suggest that exposure to road traffic noise is associated with a higher risk for hypertension both before and after adjustment for air pollution”

“Exposure to railway noise at enrolment of 60 dB or more was associated with an 8% higher risk for hypertension”

“long-term exposure to road traffic noise was weakly associated with a higher systolic BP”

High blood pressure is a major risk factor for cardiovascular disease and, therefore, even small increases in BP from road traffic noise may have high impact on public health”
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Monday, December 5, 2011

Do the Suburbs Have a Future?

The Death of the Fringe Suburb (Christopher B. Leinberger, New York Times, Nov. 25, 2011)

Also discussed here: Here Comes the Neighborhood (Christopher B. Leinberger, The Atlantic, June 2010)

And here: The Future of the City- Special Report (The Atlantic, Jun. 8, 2010)

Today we look at the future of traditional North American cities with sprawling suburbs and large malls that can only be reached by car. Population trends toward an older society, the rise of carbon fuel costs and the desire for a better life style have shifted home buyers to the urban core from the suburban fringe- with huge impacts on what is left in the suburbs and the future priorities for transportation.

Key Quotes:

“It was predominantly the collapse of the car-dependent suburban fringe that caused the mortgage collapse”

“In the late 1990s, high-end outer suburbs contained most of the expensive housing in the United States, as measured by price per square foot…..Today, the most expensive housing is in the high-density, pedestrian-friendly neighborhoods of the center city and inner suburbs”

“Many boomers (born between 1946 and 1964) are now empty nesters and approaching retirement.. will downsize their housing in the near future. … live in a walkable urban downtown, a suburban town center or a small town”

“The millennials (born between 1979 and 1996) are just now beginning to emerge from the nest … favors urban downtowns and suburban town centers — for lifestyle reasons and the convenience of not having to own cars”

“only 12 percent of future homebuyers want the drivable suburban-fringe houses that are in such oversupply…Add the fact that the houses were built with cheap materials and methods to begin with, and you see why many fringe suburbs are turning into slums, with abandoned housing and rising crime”

“The cities and inner-ring suburbs that will be the foundation of the recovery require significant investment at a time of government retrenchment. Bus and light-rail systems, bike lanes and pedestrian improvements — what traffic engineers dismissively call “alternative transportation” — are vital”
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Friday, December 2, 2011

Estimating the Risk of Death from Air Pollution

Assessment of Deaths Attributable to Air Pollution: Should We Use Risk Estimates based on Time Series or on Cohort Studies? ( 6 page pdf, N. Künzli, S. Medina, R. Kaiser, P. Quénel, F. Horak, Jr., and M. Studnicka, American Journal of Epidemiology, Vol. 153, No. 11, 2001)

Today’s review looks at an analysis of the two ways of estimating the risk of death from air pollution- as an event from immediate pre-death conditions over a short time (using time series) or as a cumulative result over a lifetime using cohort groups. The authors suggest that each risk estimate has value and each has strengths and weaknesses. The analysis could be useful in suggesting what and how often to monitor and how to use the data.

Key Quotes:

“The “frailty” concept is useful in acknowledging that, in most cases, the probability of death is influenced not by one single factor, e.g., air pollution, but rather by a function of a whole set of underlying conditions or risk factors”

“Time-series studies model the association between the probability of death and the level of air pollution shortly before the event”

“Cohort studies model the association between an exposure and time to death. Thus, in cohort studies, time is the outcome measure of interest.. the cohort study design requires a setting with spatial variability of long term exposure”

“several patterns of exposure may influence time to death:
  1. a single exposure occurring once in the past over a short period of time (e.g., an accidental spill);
  2. repeated exposures of short duration;
  3. continuous exposure over a longer period of time;
  4. a pattern of short term exposure just before death; or
  5. a combination of all of the above”
“categories of death associated with air pollution:
  • air pollution increases both the risk of underlying diseases leading to frailty and the short term risk of death among the frail;
  • air pollution increases the risk of chronic diseases leading to frailty but is unrelated to timing of death;
  • air pollution is unrelated to risk of chronic diseases but short term exposure increases mortality among persons who are frail; and
  • neither underlying chronic disease nor the event of death is related to air pollution exposure”
“we have conceptually shown that time-series based numbers of attributable cases must underestimate the total effect”

“assuming the availability of long term air pollutant monitoring data, exposure may be defined for different periods of life and for a variety of patterns (e.g., number of peaks, seasonal averages, cumulative exposure, etc.)”

“both types of air pollution mortality studies— the time-series approach and the cohort approach—are of value in air pollution epidemiology. However, they measure two different aspects of mortality that are not interchangeable”
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Thursday, December 1, 2011

The Health Impact of Indoor Air Pollution

Ball-and-stick model of the acrolein moleculeImage via WikipediaMethod to Estimate the Chronic Health Impact of Air Pollutants in U.S. Residences (29 page pdf, Logue JM, Price PN, Sherman MH, Singer BC, Environ Health Perspect, Nov.17, 2011)

Today we review research into indoor air quality as it effects health on a long term basis. The main sources of the three main pollutants (aside from radon), formaldehyde, acrolein and particulate matter are emitted from materials around the house and from tobacco smoking- with some PM coming from outdoor sources. The total health impact is 1,100 Disability Adjusted Life Years (DALYs)

Key Quotes:

Air pollutant concentrations in many homes exceed health-based standards for chronic and acute exposures…Americans spend more than 65% of their time in residences”

“In this study we combined disease incidence and DALY-based health impact models to develop a methodology to estimate the population average health costs due to chronic inhalation of a broad suite of air pollutants in U.S. assess population health impacts of large-scale initiatives – including energy efficiency upgrades and ventilation standards – that affect indoor air quality”

“Our analysis demonstrates that in the majority of U.S. residences PM2.5, acrolein, and formaldehyde dominate health impacts due to chronic exposures to non-biological air pollutants”
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