Saturday, April 6, 2013

Canaries struggling to improve environmental health: Earth Poisoning diary month 3

In 1989 I was a junior doctor in a sparsely populated part of north western Tasmania, Australia’s island state. One day, I discovered the journal Archives of Environmental Health. In it I found the proceedings of the first meeting of the International Society for Environmental Epidemiology (ISEE). This was tremendously encouraging, for reasons I will explain. The article with the greatest impression was by John Goldsmith, keynote speaker. He wrote:

"We, the environmental epidemiologists of the world, are the canaries, capable of giving warning of impending environmental disaster in time for remedial steps to be taken. Fortunately, our fate is not to have to die as the unfortunate canaries of the coal miners did, but to sing, to call out in clear tones the nature and type of impending health danger that threatens. It is the methods and criteria of scientific detection, analysis, and interpretation that give us our lifesaving potential."
Tasmania is Australia’s poorest state financially and is far from markets and population centres. Its name dates only to the 1850s, a marketing exercise as its European predecessor (Van Diemen’s Land) was so tainted by brutality, both to its indigenous people and its white convicts, transported from Britain until the 1850s. The state still has the lowest levels of education and the highest rates of chronic disease found in Australia, other than among its indigenous people. Its isolation, low population density and poverty have helped preserved unusually rich environmental qualities. But it retains a frontier mentality in which the natural environment has been repeatedly assaulted in attempts to wrest a living, whether by logging, hunting, fishing, mining, or farming. Its high rainfall and numerous rivers have also stimulated an intensive hydro-electricity industry, so successful that in most years, the entire state’s electricity supply does not rely at all on coal or other fossil fuels.

Three steps towards environmental epidemiology

1. The Wesley Vale pulp mill and its link to ecological integrity

In early 1989, three events were crucial to my evolving understanding of environmental epidemiology and environmental health. First was my involvement with the campaign to stop the expansion of a pulp mill on the north west coast. A tactic was to raise community concern about the possible adverse health effects of persistent organic pollutants (chemicals) (acronym POPs) called organochlorines, which the mill was to discharge into Bass Strait, and which would accumulate in the marine food chain. Though I was concerned about that, I was even more concerned with the proposed massive expansion of the paper industry, which would in turn lead to a huge increase in log truck traffic and harm to biodiversity and what is now conceptualised as “ecological integrity. This term, allied to “land sickness”, “ecosystem health”, “ecosystem services” and, more recently, “ecohealth” links human well-being and health to ecological conditions.

Humans have operated as “patch disturbers” for millennia (well before the development of agriculture), altering both landscapes and biodiversity on continental scales. However our collective capacity to change nature has expanded enormously, to include the intrusion of synthetic chemicals. But much damage to ecological integrity is old-fashioned; physical means aided by technology and a bonanza of cheap fossil fuels. 

In Tasmania, there have been numerous attacks on ecological integrity, including harm to water quality, not only from the clearing of forests (e.g. increasing water run-off, cloudier water and the drying up of creeks in dry periods), but also from the use of chemical involved in forest “regeneration”. These include the herbicide atrazine and the poison “1080” (sodium fluoroacetate) widely used to kill fauna (especially wallabies) which  might otherwise feast on young tree seedlings, planted to replace the old-growth forests. Bio-accumulation of poisons, with consequent immuno-supression, has been speculated as linked to the transmissible facial tumor disease of the Tasmanian devil, the state’s top non-human predator. This disease emerged about the time of large-scale forestry and its extensive use of poisons.
I was intrigued by the concept of bio-accumulation, and increasingly motivated by my daily work with patients, some of whom developed cancer or other severe illnesses at young ages, while others lived to be octogenarians. A very common question for an ill person was “why?” Apart from smoking, there were few clues. High exposures, or unusual sensitivity to pesticides and other POPs seemed a worthwhile hypothesis to explore. We now know that the organochlorine dieldrin, the use of which is declining, has been convincingly linked to breast cancer.

2. The lack of co-operation between industry and science

I developed an ambition to conduct a study of the long-term health of the pulp mill workers, and visited the School of Public Health at the University of Sydney to explore this idea as a research thesis. I received mild encouragement. But it was clear that I would need the co-operation of the mill management. Later that year I asked a senior manager at the mill about this. I envisioned a careful scientific study, seeking to explore whether the mill workers, presumably exposed to higher OCL levels than the community, might have unusual patterns of illness. (I did not then fully understand the Healthy Worker Effect.)

It was obvious that my own career depended crucially on a fair interpretation of the evidence. But his answer was violent: “anyone but f***ing you, Butler”. He clearly assumed I would be biased, yet I knew that no-one without a strong pre-existing interest would have the motivation to conduct such a study. H
is opposition meant that any such study was impossible.

3. Herbicides, two mysterious deaths, and a tepid government report 

The last key preparatory event was an encounter with a patient who told me an odd story of a healthy young woman riding a horse across the bridge at Forth, a nearby village, in the centre of a rich farming area. While crossing the bridge, a crop-dusting plane had flown overhead, discharging herbicides. My patient told me that within a year, both the woman and her horse had died.

I retrieved a short report about this event, prepared by the Tasmanian Health Department. No author was listed. Inexperienced as I was, it was clear that the report was hopelessly inadequate from a scientific perspective (I can’t recall if the fate of the horse was mentioned). Its conclusion that the two events (the spray and the death) were unrelated was completely unconvincing. Pesticide overspraying still occurs.


At that time, health interest in climate change was just starting.
The Brundtland Report ("Our Common Future") had recently popularised the term “sustainable development” and the Montreal Protocol was recent. The Green movement was taking root, not only in Tasmania but also in parts of Europe. 

Environmental transformation is necessary to provide goods and services for humans, but doing so too hastily and on too large a scale was obviously dangerous. It seemed to me that environmental epidemiologists might be able to sound an effective warning.

Twenty four years later it is hard to be as optimistic. The strain of neo-liberalism that existed then seems almost civilised compared to today's. The Savings and Loans scandal of the 1980s generated numerous prosecutions. So far, the much bigger scale of fraud that precipitated the 2008 global financial crisis has not led to a single high-level prosecution. Poorly regulated, poorly understood chemicals continue to pollute the biosphere. While human numbers and average life expectancy continue to rise, numerous danger signs are evident, from declining bee populations (whose health is linked to chemicals) to an almost inevitable rise in global temperature of four degrees, with consequent profound, adverse health effects. Limits to growth, including of human size and health,  are on the horizon, perhaps just over the next hill. 

We do need to continue to transform nature in ways that will benefit humans, but the process is not infinite. We also have to protect nature so that humans can continue to benefit. We have to wean ourselves from earth poisons. We have to slow population growth, by spreading female education and human rights. Many of us need to learn to live with less.

"Accredited” authorities remain optimistic about humanity’s future, though histories of the near future report our collapse as a civilisation. The scope of environmental epidemiology is growing, and now includes limits to growth. But not enough people are paying attention to we canaries. The noรถsphere - planetary consciousness - is evolving, but those who sound warnings need to tweet much louder.