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31
Jan
2017

Curbing Catastrophe: Sugar is the New Lead

Timothy H. Dixon

Curbing Catastrophe by Tim Dixon

Sugar Is the New Lead:

The Toxic Power of Special Interests, and Why Medical Researchers Should Take a Geology Course

 

Geologists who study natural hazards spend a lot of time worrying about historical and longer-term records of events such as earthquakes, tsunamis and volcanic eruptions.  Only with a good understanding of the location, size and frequency of past events can we give sound advice about future ones.  Looking at a sufficiently long record is critical; several thousand years is often considered a minimum.   The managers of the Fukushima Daichi nuclear power plant in Japan got into trouble in 2011 by ignoring the available information.  On March 11 of that year, Japan was struck by a powerful earthquake and tsunami that would prove to be the country’s and the world’s costliest natural disaster.  The main problem was not the earthquake itself – losses were minimized thanks to Japan’s well-designed, earthquake-resistant infrastructure.  Thirty minutes after the earthquake, however, a massive tsunami struck the north coast, knocking out cooling systems at the power plant, which were not designed to withstand high water. The nuclear fuel began to overheat, leading to a nuclear operator’s worst nightmare – core meltdowns, hydrogen explosions that fractured containment vessels, and massive releases of radioactivity.  The tsunami was foreseeable – geologists had warned of the occurrence of similar events in the past.  Unfortunately, the Fukushima managers only considered earthquakes that had occurred in the immediate vicinity of the plant in the past 100-150 years –a place and period without giant earthquakes.  Had they considered a longer time scale, or a somewhat larger area, or the possibility of large tsunamis from more modest-size earthquakes (which occasionally happens) the likelihood of large tsunamis would have been apparent – they strike the region every few hundred years.  At the plant’s location a large earthquake and tsunami similar to the 2011 event struck in 869 AD, more than 1100 years earlier (a blink of the eye for geologists).

“Think

Long-Term”

The geologist’s mantra (“Think long-term”) also applies to many health and environmental problems.

 

Gary Taubes, an American science writer, published a book in 2016 outlining the health hazards of eating too much sugar.  These include obesity, hypertension, diabetes, stroke, coronary heart disease, and possibly some types of cancer.  Perhaps the case against sugar should have been obvious.  Indigenous populations only develop these ills when they are introduced to western diets, which are rich in sugar (they are also rich in fat, but so were the original diets of many native populations).  But proving that sugar was the main culprit using standard clinical trials was difficult.  A typical clinical study might follow a group of individuals over a short period, one to several years.  For many people, the worst effects of high sugar consumption don’t show up for several decades.  The same can also be true for high-fat diets, hence separating the two is difficult without long-term studies of large numbers of people.  Long-term here could mean longer than a typical scientist’s research career, so it’s not surprising that this problem has remained controversial-  it takes a long time for conclusive studies to be performed, and it can be difficult to get such studies funded.

CocaCola bottle

By Hariadhi [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons

But incomplete nutritional research was not the only problem.  Taubes describes the case of a researcher in the 1960’s who first pointed out sugar’s evils, only to be savaged by other researchers in the field who promoted the concept that dietary fats were the main problem.  It turns out that some of these other researchers were supported by the Sugar Association, an industry-lobbying group.  One year prior to Taube’s book, Marian Nestle published a book outlining similar tactics by companies selling sugary drinks.  These obvious conflicts of interest should have been a red flag for any reputable reporter writing about health issues related to sugar, or any scientist reviewing papers or proposals on the topic.  I remember reading newspaper articles about the fat versus sugar debate in the 1980’s, and recall being convinced that high fat diets should be avoided, but sugar, at least in moderation, was OK.  I might have thought differently had I known that some of the scientists quoted in those articles were funded by the sugar industry.   Reporters and many scientists apparently forgot that other important rule, “Follow the money.”

 

Sugar and sugary drinks have been compared to tobacco in terms of their long-term health impacts, and in the role played by special interests in manipulating the media and public opinion to hide the products’ harmful effects.

 

The issue is also reminiscent of another health and environmental problem that played out a few decades earlier.  Leaded gasoline was first introduced in the 1920’s.  Lead improved engine performance and eliminated “knocking”, caused by premature ignition of the fuel-air mixture.  However, lead is also a deadly neurotoxin, especially harmful to pregnant women, infants, and young children.  It has been implicated in miscarriages and stillbirths in adult females, and reduced sperm count and abnormal sperm in adult males.  Lead is even more dangerous for children, affecting their brain development.  Children exposed to enough of it grow up with reduced intelligence, and impaired concentration, reflexes, and impulse control.   There is evidence that lead exposure in childhood increases the chances of subsequent criminal behavior.  Some historians believe that excess lead consumption contributed to the fall of the Roman empire (the Romans used lead in everything from plumbing to cooking vessels to sweeteners to cosmetics).  Its tough to defeat the Barbarians when your leaders have muddled thoughts and your centurions have muddled reflexes.

 Lead is a deadly neurotoxin, especially harmful to pregnant women, infants, and young children

Fig 1 Soil lead pollution in London England

Figure 1. Soil lead pollution in London England (orange and red colors indicate higher lead levels). The worst pollution is near the city center, where major roadways cross. This pattern is typical of most cities world-wide, wherever leaded gasoline was used. Reproduced by permission of the British Geological Survey © NERC. All rights reserved. CP14/021.

Airborne lead is especially harmful because lead taken into the lungs is absorbed directly into the bloodstream.  Putting lead into gasoline was an especially bad idea because it contaminated the air wherever there was lots of traffic, i.e., cities, where most people live.  Leaded gasoline’s toxic legacy lives on today.  When lead falls out of the atmosphere, it contaminates the soil, and is easily re-mobilized later in dust.  Places with lots of roads, in or near city centers, tend to have the worst soil lead pollution (Figure 1).  While overall lead contamination has improved, it remains a problem in inner cities and poorer neighborhoods, which tend to have lots of freeways and major roads, and where lots of lead was deposited over the decades when leaded gasoline was used (1920s – 1970’s in the US, Canada and most of western Europe; some countries still use it today).  Factories that use and disperse lead also tend to be located disproportionately in poorer neighborhoods.

 

Global lead contamination started during the time of the Roman Empire

 

 

 

 

Gas Pump Lead Warning

Joe Mabel [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0/)], via Wikimedia Commons

Clair Patterson, a geologist at Caltech, was a well-known scientist who first figured out the age of the Earth.  Patterson used a technique called lead isotope geochronology (isotopes of an element like lead or uranium have the same chemical properties but slightly different masses).  Uranium in rocks slowly changes into lead, by a process of radioactive decay, and since the rate of change is known, measuring the amount and isotope composition of lead in the rock gives the age of the rock.  I once attended a lecture by Patterson, expecting to hear about his groundbreaking work on Earth’s age, 4.5 billion years old (much older than people had thought).  Instead, Patterson talked about lead pollution.   In his research he noticed that some of his samples were contaminated with modern lead, and realized that leaded gasoline was the main culprit.  In his attempts to understand the problem, he also came to understand that modern humans were absorbing lead in large quantities, perhaps large enough to threaten human health.  But how much of this lead was natural (what geologists sometimes call “background”)?  To find out, he had to go back in time to a period when no extra lead was being re-mobilized into the environment by human activities.  The way he did this is fascinating – he used ice from Greenland.  Greenland’s ice sheet accumulates slowly as each year’s snowfall is compressed by next year’s snow fall.  Snow crystals trap a little air when they fall, retaining a record of atmospheric composition.  By studying the annual layers of ice, you get a sense of the average amount of lead in Earth’s atmosphere for that year.  Patterson’s results showed that you have to go back at least 200 years, prior to the industrial revolution, to get low-lead samples.  Later work on Greenland ice cores would prove that global lead contamination started during the time of the Roman Empire.  In other words, if you want a true natural background for lead concentration in humans, you need to go back more than 2000 years.  Current medical evidence suggests that there is no safe level for lead in humans.  In other words, we’ve been poisoning ourselves for a long time.  It’s interesting to speculate how history might have been different if lead had never been discovered – we might all be smarter.  Patterson also showed that global lead contamination really took off after the introduction of leaded gasoline in the 1920’s and 1930’s.  Aware of the implications for human health, he campaigned tirelessly to have it banned.

we’ve been poisoning ourselves for a long time.

Ethyl Corporation (originally started by Exxon and GM), the main marketer of leaded gasoline in the US, used its industry lobbying group, the American Petroleum Institute (API), to discredit Patterson’s work.  In a Wall Street Journal article published September 9, 1965, API stated that the while his findings “may be of academic interest . . . they have no real bearing on the public health aspects of lead. Contrary to Mr. Patterson’s conclusion, the mass of evidence proves unquestionably that lead isn’t a significant factor in air pollution and represents no public health problem in any way.”  Given the well-known toxicity of lead and Patterson’s compelling evidence for its planet-wide dispersal, this was an astonishing statement.  Unfortunately, it went unchallenged by the Wall Street Journal reporter.  The Journal further undermined Patterson’s message by quoting a medical professional, Dr. Leonard Goldwater of Columbia University, who characterized Patterson’s statements as “misleading.”  Goldwater had studied blood lead concentrations in humans over a 30 year period, a time span when there wasn’t much change.  Goldwater’s mistake was similar to that of some later researchers who first looked at sugar’s health effects – his time scale was too short.  Even Goldwater’s oldest samples were contaminated with lead – his earliest samples started after the introduction of leaded gasoline.  Goldwater was a well-respected medical professional, but his mistake would have been obvious even to first year geology students, who are taught, first and foremost, to think long-term.

His time scale was too short.  Even Goldwater’s oldest samples were contaminated with lead

Crime vs Lead = 22 years

Figure 2. Data on violent crime (including murder, rape and armed robbery) from the US Federal Bureau of Investigation (FBI) Uniform Crime Reporting data base. Data on lead from Nriagu (1990) and National Academy Press (1993).

 

 

 

 

Ethyl Corporation and API managed to delay the imposition of much-needed controls on leaded gasoline by at least a decade.  The costs to society for this “lost decade” are difficult to calculate, but are probably extremely large.  Consider just one example – the fall of crime rates in the US that occurred in the early 1990s, about 20 years after the decline in use of leaded gasoline.  Lead exposure reduces IQ and impulse control in young children, and these unfortunate children are more likely to commit violent crimes when they grow up.  Figure 2 shows the rate of violent crime in the US since 1960, and compares it to the amount of lead used in leaded gasoline over a similar period, lagged by 22 years, close to the average age of felons when they are first incarcerated for a violent crime. Reyes (2007) and Nevin (2007) give more detailed discussion of this fascinating correlation.  These and other authors estimate that at least 50% of the fall in the US crime rate in the 1990’s can be explained by the reduced use and subsequent ban on leaded gasoline.  It’s a great example of what some common sense regulation can achieve.

 

Just like lead, the impacts of sugar are falling disproportionately on people living in inner cities and poorer neighborhoods, and will continue long into the future.   Savvy and well-off elites have been concerned about the links between sugar and health for several decades.  Consumption of one of the main sugar delivery vehicles, sugary drinks, has steadily fallen in this demographic.  Companies that peddle sugary drinks have noticed this and have changed the their advertising to focus on the inhabitants of poorer neighborhoods.  Just like Ethyl Corporation, the companies selling these products will not likely pay for the great long-term harm they are doing to society.  Governments that try to regulate the advertising  for these products or tax them run into a barrage of criticism from supposedly independent “think tanks” who claim to be protecting personal liberty and the free market.  A little bit of investigative reporting would likely show that some of these groups are not so independent, but are funded by “Big Sugar” or “Big Soda”.

“Follow

the Money”

 

 

This article is based on material in Chapter Six, “Nuclear Power, Coal, and Tuna: the Concept of Relative Risk.” of Timothy Dixon’s new book Curbing Catastrophe: Natural Hazards and Risk reduction in the Modern World.

 

Further Reading

Aufderheide, A., G. Rapp, L. Wittmers, J. Wallgren, R. Macchiarelli, G. Fornaciari, F. Mallegni, & R. Corruccini (1992) Lead exposure in Italy: 800 BC-700 AD. International Journal of Anthropology, 7, 9-15.

Bryson, B. (2005) A Short History of Nearly Everything.  Random House, New York,   624p.  Includes an excellent summary of Clare Patterson’s fight against leaded gasoline.

Davidson, C. I., ed. (1999) Clean hands: Clair Patterson’s crusade against environmental lead contamination.  Nova Science, 162p.

Denworth, L. (2009) Toxic Truth: A Scientist, A Doctor, and the Battle over Lead, Beacon Press.Gilfillan, S. C. (1965) Lead poisoning and the fall of Rome, Journal of Occupational Medicine, 7, 53-60.

Hiaasen, C (1993) Strip Tease.  Warner Books, 418 p.   A fast-paced and darkly humorous “roman a clef” about the corrupting role of “Big Sugar” in Florida and Washington politics.

McGrayne, S. B. (2001) Prometheans in the Lab.  McGraw-Hill, 243 p.

Mielke, H. (1999) Lead in the inner-cities, American Scientist 87, 62-73.

Montgomery, J., J. Evans, S. Chenery, V. Pashley, & K. Killgrove (2010). ‘Gleaming, white, and deadly’: using lead to track human exposure and geographic origins in the Roman period in Britain. Roman Diasporas, Journal of Roman Archaeology, Suppl 78, 199-226.

Needleman HL, C. Gunnoe, A. Leviton et al. (1979) Deficits in psychological and classroom performance of children with elevated dentine lead levels. New England Journal of Medicine 300, 689–695.

Needleman HL, Schell A, Bellinger D, Leviton A, Allred EN (1990) The long-term effects of exposure to low doses of lead in childhood. An 11-year follow-up report. New England Journal of Medicine, 322, 83–88.

National Academy of Sciences (1993) Measuring lead exposure in infants, children, and other sensitive populations.  National Academy Press, Washington DC, 337p.

Nestle, M. (2015) Soda Politics: Taking on Big Soda (and Winning).  Oxford University Press, Oxford (UK), New York (US) 508 p.

Nevin, R. (2007) Understanding international crime trends: The legacy of preschool lead exposure.  Environmental Research 104 (2007) 315–336

Nriagu, J. O. (1983) Lead and lead poisoning in antiquity.  Wiley-Blackwell, 454 p.

Nriagu, J. O. (1990) The rise and fall of leaded gasoline. Science of the Total Environment 92, 13-28.

Oreskes, N., E. M. Conway (2010) Merchants of Doubt: How a Handful of Scientists Obscured the Truth on Issues from Tobacco Smoke to Global Warming. Bloomsbury Press, New York.

Patterson, C. (1956), Age of meteorites and the Earth, Geochimica et Cosmochimica Acta 10 (4): 230–237.

Patterson, C. (1965) Contaminated and natural lead environments of man, Archives of Environmental Health, 11, 344-360.   This paper was the first to show that high lead levels in humans living in industrial nations are both widespread and man-made.

Reyes, J. W. (2007) Environmental policy as social policy:  The impact of childhood lead exposure on crime. National Bureau of Economic Research, Working Paper 13097, 68p.

Rosman, K. J. R., W. Chisholm, S.  Hong, J.-P.  Candelone, and C. F. Boutron (1997) Lead from Carthaginian and Roman Spanish mines isotopically identified in Greenland ice dated from 600 B.C. to 300 A.D. Environmental Science and Technology, 31, 3413–3416.

Taubes, G. (2016) The Case Against Sugar.  Knopf, 368p.

About The Author

Timothy H. Dixon

Timothy H. Dixon, author of Curbing Catastrophe, is a Professor of Geology and Geophysics at the University of South Florida, Tampa, and a former commercial pilot....

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