CHNET-Works! - Newsletter

CHNET-newsletter banner


...... ..................  upcoming webinar button ...... ..................
 How to register button ...... ................... archived webinar button

Health as if everybody counted blog


Acting on social determinants of health: how much do we need to know?

Posted by Ted Schrecker
Ted Schrecker
Ted Schrecker is a clinical scientist at the Élisabeth Bruyère Research Institut
User is currently offline
on Friday, 09 March 2012
in CHNET-Works!

Many readers will remember the sequence of events in which former football star O.J. Simpson was acquitted of the murder of his estranged wife and a friend in a criminal trial, yet found liable for damages in a civil suit brought by the family of one of the victims. Leaving aside the sociological roots of the not-guilty verdict in the United States' tragic history of racial antagonisms, in analytical terms the discrepancy can be explained with reference to the higher standard of proof in a criminal trial (proof beyond a reasonable doubt) than in a civil proceeding where a claim for damages can be sustained on a preponderance of the evidence or, in some common law jurisdictions, on the balance of probabilities.

The idea of a standard of proof is critical to understanding the question posed in the title of this posting. A classic article published in 1978 by economist Talbot Page (1) used this concept to analyze public policies toward "environmental risks" like toxic chemicals, which share such characteristics as incomplete knowledge of the mechanism of action, long latency periods between exposure and illness, and irreversibility. He pointed out that most forms of scientific inquiry are organized around minimizing Type I errors – that is, 'false positives' or incorrect rejections of the null hypothesis. Page used the analogy of the standard of proof in criminal trials, and went on to argue that minimizing Type I errors may be a thoroughly inappropriate principle when applied to use of scientific evidence in public policy, because it fails to take into account uncertainty and consequences. Stated another way, "a risk/benefit assessment," albeit often an implicit one, "is part of every public policy action which is based upon the interpretation of the results of a scientific investigation." (2)

Evidence-picture-1Waiting for "evidence of dead bodies" may be inappropriate when responding to health threats from environmental hazards.
Photo by biofriendly, reproduced under a Creative Commons licence.

This point has often been lost sight of in controversies about controlling toxic exposures in the environment and the workplace, with industry resisting regulation by demanding stronger – usually epidemiological – evidence and trying to cast the issue as one of scientific uncertainty: demanding what another economist has described as a "tobacco industry standard of proof." (3) Page correctly pointed out that: "In its extreme, the approach of limiting false positives requires positive evidence of 'dead bodies' before acting." This is, in fact, the standard of proof that has often been applied to research on the health effects of environmental hazards. A further point of importance is that the conventional threshold of statistical significance – 95 percent – may require extremely large and unmanageable sample sizes when the prevalence of a particular adverse outcome is only moderately elevated over background levels. (4) As Page pointed out, "there is literally no information content in a negative finding unless there is an analysis of ... the probability of a false negative." (1)

Choosing a standard of proof for purposes of public health policy therefore is unavoidably an ethical decision, having to do – as yet another author pointed out at around the same time – with the relative acceptability of being wrong in different kinds of ways (5) while we wait for evidence that may or may not be obtainable. Interestingly, a workshop on conceptual and methodological issues in public health science held at the University of Cambridge in 2010 revisited these questions, suggesting that understanding of them in the relevant research communities remains incomplete, even as they remain topical with respect to such issues as environmental causes of breast cancer .

The question of how much evidence is needed for action on social determinants of health underscores the value-laden nature of choices about the appropriate standard of proof. At least two issues are critical.

First, what kinds of research findings are relevant? Clinical epidemiology now widely accepts a hierarchy of evidence with the randomized controlled trial (RCT) at the top; presumably, this is what two authors writing on global health governance had in mind when they claimed that "[f]ew global health interventions are evidence-based, and interventions to improve population health among the poor are often untested ..." To some of us, this assertion is nothing short of bizarre, and neglects the fact that many interventions outside clinical settings cannot be assessed using RCTs, for reasons of ethics, logistics, or both. Colleagues and I pointed out a decade ago, in the context of research on preventing mental illness, that "choosing certain research strategies and standards of proof means the big questions ... probably will not be studied in ways that demonstrate the effectiveness of larger-scale, contextual interventions, and even the small questions will be asked in ways that seriously circumscribe the set of possible answers."

A methodologically pluralist approach, organized around what a former colleague calls a "portfolio of evidence," will yield more meaningful and policy-relevant answers. Unbeknownst to us, Michael Marmot had made a similar point the previous year in a general discussion of evidence for influences on population health: "The further upstream we go in our search for causes ... the less applicable is the randomized controlled trial. .... We must therefore rely on observational evidence and judgment in formulating policies to reduce inequalities in health. In this process, the best should not be the enemy of the good. While we should not formulate policies in the absence of evidence to support them, we must not be paralyzed into inaction while we wait for the evidence to be absolutely unimpeachable." (6) He continues to make this point.

Food-bank-can-use-help395,000 Ontarians received help from food banks in March, 2011.
Image courtesy Ontario Association of Food Banks.

Second, is it necessary to wait for evidence that a particular policy or intervention leads to improved health outcomes, or is it sufficient to have evidence of reduction in risk factors or what might be called intermediate biological variables (like markers of allostatic load, in the context of prolonged stress) that are known to have an adverse effect on health outcomes? This question gains urgency from knowledge of the cumulative effects of negative contextual influences on health over the life course: "waiting for dead bodies" in this case, as in others, can amount to carrying out a large-scale experiment on non-consenting subjects, the results of which may not be available for a generation. Obviously, ongoing evaluation of interventions and policy changes is important, but how much more do we need to know before (for instance) doing what it takes to reduce food insecurity among people for whom eating a healthy diet while paying market rents is arithmetically impossible?

This is a rather polemical way of stating the question, but it is useful in order to get at the hard politics of debates about evidence. Many policies and interventions needed to reduce health disparities by way of social determinants of health will be explicitly redistributive – starting with reductions in income inequality, as noted in a forthcoming editorial in the American Journal of Public Health. As mentioned, companies facing costly regulation of their activities have long found it attractive to frame their opposition as based on the insufficiency of scientific evidence. Similarly, those who stand to lose from tackling "the inequitable distribution of power, money, and resources" – one of the three overarching recommendations of the Commission on Social Determinants of Health – may frame their opposition in terms of the need for more evidence rather than simple self-interest. One-percenters, and those on a fast track to that status, are not a natural constituency for redistributive policies. This is not of course the only explanation for hostility to the social determinants of health agenda, but it cannot be disregarded. Against this background, it's especially important to keep in mind that the appropriate questions are not only about the strength of evidence, but also about how uncertainty should be resolved in a context where "deferring a decision is a decision in itself." They are, in other words, rooted firmly in the domain of public health ethics. Only by insisting on this point can we be sure that debates about when and how to act involve – as they should – the language of values and social justice.

(1) Page, T. (1978) A Generic View of Toxic Chemicals and Similar Risks. Ecology Law Quarterly, 7, 207-244.

(2) Darby, W. (1979) An Example of Decision-Making on Environmental Carcinogens: The Delaney Clause. Journal of Environmental Systems , 9, 109-117.

(3) Crocker, T.D. (1984) Scientific Truths and Policy Truths in Acid Deposition Research. In T. Crocker, ed., Economic Perspectives on Acid Deposition Control (pp. 65-79). Ann Arbor Science Acid Precipitation Series vol. 8. Boston: Butterworth.

(4) See e.g. Higginson, J., Muir, C.S., Muñoz, N. (1992) Human Cancer: Epidemiology and Environmental Causes (pp. 39-44). Cambridge: Cambridge University Press.

(5) Jellinek, S. D. (1981) On the Inevitability of Being Wrong. Annals of the New York Academy of Sciences, 363, 43-47.

(6) Marmot, M. (2000). Inequalities in Health: causes and policy implications. In A. Tarlov & R. St.Peter, eds., The Society and Population Health Reader, vol. 2: A State and Community Perspective (pp. 293-309). New York: New Press.

0 votes
Hits: 5199

HEST: A new frontier for action on health equity? *

Posted by Ted Schrecker
Ted Schrecker
Ted Schrecker is a clinical scientist at the Élisabeth Bruyère Research Institut
User is currently offline
on Tuesday, 28 February 2012
in CHNET-Works!

In December 1995, Cynthia Wiggins was hit by a dump truck while crossing several lanes of traffic in suburban Buffalo, New York; shortly afterward, she died from her injuries. The 17-year-old African-American woman had to cross the arterial road from her bus stop because the bus that took her from downtown to her job in the posh Walden Galleria mall was not allowed on mall property. It was later revealed that the local public transportation authority had for years tried, unsuccessfully, to get permission to stop in the mall's parking lot. In 1999, a lawsuit charging the mall's owners with racial discrimination was settled for $2.55 million (to benefit Ms Wiggins' son) without admission of liability.

Ms Wiggins' death is an especially dramatic example of the connections between transportation policy and social exclusion: specifically, support for a form of apartheid in the United States long after it was challenged in legislation and jurisprudence. In Los Angeles, The Bus Riders' Union has used a variety of tactics, including litigation under national civil rights legislation, to seek improvements in a transit service that mainly serves a darker-skinned, subaltern population unable to afford the costs of driving in a car-oriented metropolis. Although we are not (yet) familiar with similar extremes in Canada, an important and neglected 2009 report prepared for Human Resources and Social Development Canada on mobility and social exclusion in Hamilton, Toronto and Montréal concluded that "the evidence uncovered in terms of mobility and accessibility patterns is suggestive of social exclusionary processes that may prevent various vulnerable groups," specifically low income people, seniors and single parent households, "from accessing the places required for their daily needs." Since social exclusion functions as a social determinant of (ill) health, the role of transportation in social exclusion should automatically be of concern to the public health community.

There are more immediate reasons for concern. One involves the health consequences of transport-related (mainly automotive) air pollution, reviewed among many other places in a 2005 WHO-Europe report and in the same year by the Ontario College of Family Physicians. It is also likely that an inverse relation exists between income and exposure, although the relation is complicated both by the limitations of measuring exposure based on residential location (most people don't spend most of their time at home) and by the "particular social geography" of cities like Montréal. (I would be delighted if readers can identify useful literature reviews on this topic.)

A second issue is the relation between metropolitan form and injuries and deaths from road accidents, where data on the socioeconomic gradient are hard to find and primary data are often collected by law enforcement agencies, using categories that have limited relevance to population health. (Again, readers are invited to contribute sources to the conversation.) A 2003 article by Reid Ewing and colleagues developed a "sprawl index" for 448 metropolitan counties in the United States, matched this against "all-mode" traffic fatality statistics, and concluded that "sprawl is a significant risk factor for traffic fatalities, especially for pedestrians." In the ten counties with the most compact urban form, fatality rates averaged 5.6 per 100,000 population; in the ten counties with the least compact form – that is, the most sprawling ones – the average was 26.3 per 100,000 population. However, hazardous environments for pedestrians are common even in cities that are relatively compact by North American standards.

hest-picture-1-1-of-1Hazardous environments for pedestrians are common, as shown in this picture taken from the University of Ottawa’s downtown campus.

A third reason for concern involves the relation among transport policy, the built environment, and overweight and obesity, which are now recognized as one of the most urgent public health challenges. The idea of obesogenic environments has gained widespread acceptance, and represents an essential challenge to the emphasis on 'lifestyles' or 'healthy choices' that characterizes many health promotion efforts. Isolating the specific contribution of transport policy is complicated by the fact that in the metropolitan environment, many things are going on at once. For example, neighbourhoods may be more conducive to physical activity ('walkable'), but may also have few full-service grocery stores but lots of convenience stores and fast-food outlets, or neighbourhoods where the built environment is conducive to walkability may also be those where crime is highest. However, some evidence shows a direct link between settlement patterns or transportation and obesity. For example, a 2004 study using a sprawl index – not the same one used by Ewing and colleagues – and self-reports of Body Mass Index (BMI) found that each 1-point increase in the sprawl index (on a scale of 100, values for large US metropolitan areas ranged from 6 to 100) was associated with a 0.5 percent increase in the risk of obesity, after individual-level variables like income, gender, age and education were controlled for. Almost by definition, urban sprawl implies a high reliance on automobiles for transportation, as shown in a classic graph produced by Jeffrey Kenworthy

hest-picture-2-1Source: P. Newman and J. Kenworthy, “‘Peak Car Use’: Understanding the Demise of Automobile Dependence,” World Transport Policy and Practice 17 (June 2011), reproduced with permission.

Finally, there is the need to shift transportation patterns in order to limit climate change, which itself is likely to have substantial adverse health impacts that will be inequitably distributed, falling first and hardest on people and regions that contributed least to the buildup of greenhouse gases. A 2009 article in The Lancet pointed out that transport emissions are rising faster than all other categories, and argued using scenarios for London and Delhi that there would be substantial health benefits from moving to "sustainable transport" including both lower-emission motor vehicles and more walking and cycling, quite independent of the effects on climate change. Elsewhere, a recent assessment of the effects of reducing automobile usage for short trips (1.6 km or less) in the Midwestern United States came to similar conclusions, and further projected several billion dollars a year in health care cost savings. As with other studies cited here these are only selections from a very large literature, but the pattern is clear.

So far as I know, the acronym HEST (for Healthy, Equitable and Sustainable Transportation) is my own invention. There is no shortage of useful information about how to begin, starting with a WHO evidence review mentioned in an earlier posting that identified transportation as an important area for action to reduce health inequity. Kenworthy has listed "ten key transport and planning decisions for sustainable city development," including de-emphasis of freeway and road; planning for employment and housing growth in the city centre and sub-centres; and – critically – a planning process that "is a visionary 'debate and decide' process, not a 'predict and provide,' computer-driven process." (A recent Toronto Star commentary on how the city's planning is now driven by the "pseudo-science" of traffic engineering made a similar point.) Ewing and colleagues have described the "five D's of development": density, diversity, design destination accessibility, and distance to transit. This source is one chapter in an excellent book called Making Healthy Places published by Island Press. World Streets, a web site specifically devoted to "equity-based transport," is another valuable and provocative resource.

Some Canadian organizations have taken up the challenge. I've already mentioned the work of the Ontario College of Family Physicians. In 2007, Toronto Public Health produced a report on air pollution, traffic and health that concluded: "Given there is a finite amount of public space in the city for all modes of transportation, there is a need to reassess how road space can be used more effectively to enable the shift to more sustainable transportation modes" like "walking, cycling and on-road public transit." (I don't think the city's current mayor has read it.) And Alberta Health Services has produced a well researched and hard-hitting fact sheet on urban sprawl and health. Doubtless much more is going on, and I hope readers will post appropriate news, citations and links. 



Predictably, our colleagues in other countries have been less polite and more proactive. Margaret Douglas and colleagues in Britain's NHS (including the Director of Public Health for a primary care trust in Manchester) wonder whether cars are the new tobacco, pointing to the multiple negative effects on health and sustainability of auto-oriented transport systems and the influence of the "car lobby." Also from the UK, writing in the December, 2011 issue of Public Health Today Philip Insall calls for a 20 mph speed limit in residential areas, noting that some continental cities have already made this move and that it would eliminate up to 580 child deaths and serious injuries each year. (Lower speed limits are just one kind of traffic calming measure; many others involve design changes, as noted in an important review by the Canada's National Collaborating Centre for Healthy Public Policy just released last November.) And Andy Jones, writing about obesogenic environments, says: "Maybe we just need to force society to change. Excluding traffic from city centres, radically increasing parking charges, forcing employees to walk at least part of the way to work by removing workplace car parks" as well as taxing high-fat foods.

Forcing society to change can be difficult when we have things like elections, and that's as it should be. Canada's public health community could, however, be much more energetic in advocating for such changes, and providing leadership to ensure that their equity and health benefits are part of the public debate during and between elections.

* Unfortunately, as with previous postings some hyperlinks lead to sources that are not available on an open-access basis. I have tried to find open-access materials wherever possible.

Hits: 4496

Life A.D. (After Drummond), Part 1

Posted by Ted Schrecker
Ted Schrecker
Ted Schrecker is a clinical scientist at the Élisabeth Bruyère Research Institut
User is currently offline
on Monday, 20 February 2012
in CHNET-Works!

As Ontario-based readers will know, on February 15 the Government of Ontario released a far-reaching report on reorganizing public service provision in an era of austerity. The report was the work of a small commission chaired by Don Drummond, a former public servant in the federal Department of Finance and subsequently chief economist for TD Bank. The other commission members were the President of Laurentian University (base salary $304,647 in 2010); the Vice-President for Communications and Community Engagement of the Centre for Addictions and Mental Health (base salary $245,352 in 2010); and the dean of the business school at the University of Western Ontario (base salary $405,000 in 2010). These figures are matters of public record, as they should be, and are available under the Province of Ontario's salary disclosure legislation. The point is that all members of the commission were, to put it mildly, isolated from many of the influences that limit other Ontarians' ability to lead healthy lives.

The report proposed that public spending on health care – the largest item in Ontario's budget, as in that of other provinces – should grow by 2.5 percent annually over the next several years, as compared with the recent trend of 6 percent annual growth. Slower growth was recommended for public education; just 0.5 percent for "social programs"; and spending reductions of 2.4 percent annually in all other programs. However, the 'how to' rather than the 'how much' aspects of the report's recommendations may ultimately be most significant, if implemented.

The report has already generated a flood of commentary, to which I don't propose to add right now. I'll be posting a longer analysis after my presentation at Public Health Ontario's PHO Rounds on March 2, the last part of which will deal briefly with life A.D. (After Drummond). Meanwhile, the Wellesley Institute has commented on the report's neglect of broader social determinants of health that affect the prevalence of and prognosis for conditions like diabetes (the topic of one of my earlier postings). And the Toronto Star's Thomas Walkom pointed out the bias introduced by the government's instructions to the commission not to consider tax increases, at a time when the fiscal capacity of Canadian governments has been drastically reduced, while allowing it to consider user fees that will have a disproportionate impact on low- and middle-income households.

Walkom also pointed out the lack of attention to the employment impacts of a plan to take billions of dollars out of the Ontario economy by way of public spending cuts – indicative of a broader trend in which employment has all but vanished from the public policy agenda except when governments want to trot out the 'job creation' benefits of handouts to one or another corporate client. He predicts that implementation of the Drummond recommendation would lead to an Ontario unemployment rate of 11 percent by 2018, "even without another global crisis". Abundant evidence shows that not only unemployment rates but also the conditions of employment – full-time and secure versus precarious, casualized or entirely informal – and their effects on working conditions are key social determinants of health, so this is a point of some importance. (An aside to readers: would a future posting expanding on this evidence be of any interest?)

As pointed out by (among others) economist Erin Weir of the United Steelworkers, there is quite a bit in the report that those of us committed to social justice can support. There is also quite a bit that might be compatible with a "health in all policies" agenda, and with advancing health equity. Where will the public health community be as debates about the report continue in the coming weeks? How prominently, if at all, will population health and health equity figure in the discussions? Does the public health community, however defined, have an organizational platform capable of rapid, critical and effective response to events in the broader public policy environment? If not, it's high time we did.

Hits: 3812

How (some) sociologists think about health inequalities

Posted by Ted Schrecker
Ted Schrecker
Ted Schrecker is a clinical scientist at the Élisabeth Bruyère Research Institut
User is currently offline
on Tuesday, 14 February 2012
in CHNET-Works!

An exchange in the most recent issue of the journal Sociology of Health and Illness (for the moment, at least, available for open access) provides a useful overview of theoretical debates about the sources of health inequalities. Graham Scambler's review article summarizes main themes in these debates, starting with a relatively familiar typology of behavioural, material and psychosocial orientations. (Readers who have run across these terms without explanation of their contrasting initial assumptions will find Scambler's summary especially useful.) He then argues that new research directions emphasizing the origins of health inequalities in social structures are needed in order to follow through on the agenda of the Commission on Social Determinants of Health, and rather breathlessly concludes that "there is a need for a political economy of health that transcends the nation-state ... National health inequalities can no longer be explained without reference to transnational social mechanisms." Some of us, of course, have been saying this for quite a long time.

russia-poverty-picA homeless woman and her 14-year-old daughter beg for money in a Moscow metro station,
December 17, 1999.
Photo: Mark Milstein, Getty Images News, Getty Images.

There follow two brief responses. William Cockerham takes a skeptical view of Scambler's emphasis on structures. Then again, since Cockerham has attributed the mortality crisis that followed the collapse of the former Soviet economy to the lack of a "stable and resourceful middle class [that] has served as a powerful social carrier of a positive health lifestyle capable of penetrating the boundaries of other classes" (1, p. 469) – forget about a 50 percent decline in national economic product, official poverty rates over 40 percent and massive capital flight - this is perhaps to be expected. Canadian scholar David Coburn, on the other hand, lauds Scambler's focus on structural influences and indeed argues for a more explicit focus on how the operations of the global market economy magnify economic inequalities and therefore disparities in the chance to lead a healthy life.

I agree with Coburn that "structural analysis too often stays at high levels of abstraction," neglecting what philosopher of science Jon Elster has called the texture of everyday life, which is crucial to understanding how structural influences manifest themselves in the household and the neighbourhood. On this point, my main quarrel with Scambler is his apparent belief that sociology is all there is to the social science of health disparities. Political science and anthropology, to name just two other fields, have a lot to say as well – and the latter discipline, in particular, has done rather a better job of explicating the necessary macro-micro connections. A recent article by James Quesada and colleagues on the situation of Latino migrant labourers in the United States provides just one illustration among many.

(1) Cockerham WC (2007). Health lifestyles and the absence of the Russian middle class. Sociology of Health and Illness, 29, 457-473.

0 votes
Hits: 3103

Environmental justice: revived and revisited

Posted by Ted Schrecker
Ted Schrecker
Ted Schrecker is a clinical scientist at the Élisabeth Bruyère Research Institut
User is currently offline
on Tuesday, 31 January 2012
in CHNET-Works!

With a few exceptions, such as a short 2008 report from the Canadian Policy Research Networks, socioeconomic inequalities in exposure to environmental hazards have not been a central concern of Canadian population health research or public health practice. In the United States, on the other hand, the highly visible and persistent reality of racial segregation has generated a substantial stream of research and activism on environmental justice, including the establishment of units like the Environmental Justice Resource Centre in Atlanta. In 1994, an executive order issued by then-President Clinton required all federal agencies to consider environmental justice in their programs. Official interested waned (to put it politely) under subsequent Republican administrations, but the issues are now being revisited.

The December 2011 issue of the American Journal of Public Health – fortunately, available on an open-access basis – is based on a symposium on Strengthening Environmental Justice Research and Decision Making organized by the US Environmental Protection Agency in March 2010. The articles are a valuable resource for exploring both the strengths and the limitations of current US approaches to the issues, and amply support an editorial conclusion that the EPA's current approach "is not sufficient to end make progress toward ending environmental health disparities and environmental injustices," given its heavy reliance on toxicology and engineering.

env-justice-picture-1-1Reproduced with permission of the US Environmental Protection Agency

Among the many important points raised in the collected articles:

  •  An overview of methodologies points out that most existing studies of the spatial distribution of environmental health hazards rely on census data, so effectively track only nighttime exposure. People's daytime locations and exposures are harder to track, and it's certainly plausible that people living in locations where their exposure to environmental hazards is high are also more likely than others to be working in similar environments.
  •  In assessing the overall distribution of inequalities in the chance to lead a health life, it is essential to consider the combined health effects of chemical exposures and stressors of other kinds, including psychological and social stressors. A companion article by Bruce McEwen, one of the world's leading researchers on the biology of stress, elaborates on the physiological pathways that are likely to be relevant. Since population health researchers often ignore the massive accumulation of human and non-human evidence on this topic, its recognition is especially important.
  • Paula Braveman and colleagues elaborate on a now familiar definition of health equity by dealing explicitly with the issue of strength of evidence and standards of proof, arguing: "It must be plausible, but not necessarily proven, that policies could reduce [health] disparities, including not only policies affecting medical care but also social policies addressing important non-medical determinants of health and health disparities ..."

env-justice-picture-2-1Living near pollution from heavily travelled roads is one of many environmental hazards that are unequally distributed. Photo: Atwater Village Newbie

The symposium also (not always intentionally) underscores the limitations of the US approach. For a variety of reasons, many of which have to do with industry's use of the courts to resist environmental regulation, quantitative risk assessment is "the central paradigm of the Environmental Protection Agency". Especially in the case of cancer risk, it can be difficult to establish links with the spatial distribution of hazards: because of long induction and latency periods, "studies would need to include residential histories for as many as 15 to 30 years before a cancer diagnosis to capture pertinent environmental exposures," even before dealing with the problem of exposures when people are not at home – on the job, for instance. The effect is to build in a bias against regulation that requires "requires positive evidence of 'dead bodies' before acting," in the words of a classic 1978 article by environmental economist Talbot Page, unfortunately not available for open access. More generally, the emphasis on quantitative risk assessment focuses attention and resources on refining measurement techniques and building ever more elaborate models of causal pathways. An alternative, explicitly precautionary approach to environmental justice would focus instead on eliminating hazards once a much lower standard of proof is met. This tension is hardly unique to environmental justice; indeed, as Page pointed out, it is pervasive in the regulation of many kinds of health hazards.

As mentioned, environmental justice issues have had a relatively low profile in Canada. Three Canadian researchers recently argued (I think quite correctly) that institutional health promotion here has simply failed to address environmental health inequalities. Here's one of many areas related to social determinants of health in which even a modest commitment of additional research dollars is likely to generate valuable, if politically awkward, findings.

Hits: 5022
Ottawa SEO and Web Design