Pollution and Crime: Leaded Gasoline and Murder

The startling correlation between the amount of lead pollution and the murder rate 21 years later. Graph from Nevin (2012).

Rick Nevin‘s research provides a lot of evidence that the amount of violent crime — murders, aggravated assault, etc. — are the result of lead pollution. Lead was added to gasoline until the 1970’s. When the gasoline was burned in car engines, the lead was released into the atmosphere where it could get into people’s systems just by breathing.

Quite a number of studies taken together have shown that high blood lead levels result in lower IQ’s, which, in turn, seems to increase aggressive behavior.

Long-term trends in paint and gasoline lead exposure are also strongly associated with subsequent trends in murder rates going back to 1900. The findings on violent crime and unwed pregnancy are consistent with published data describing the relationship between IQ and social behavior. The findings with respect to violent crime are also consistent with studies indicating that children with higher bone lead tend to display more aggressive and delinquent behavior.

— Nevin (2000): How Lead Exposure Relates to Temporal Changes in IQ, Violent Crime, and Unwed Pregnancy (pdf pre-print) in Environmental Research.

Kevin Drum summarizes the research and goes into the details to disprove the other theories for peaks in crime rates in the last century.

The Dish

The Adolescent Sleep Cycle

Bora Zivkovic compiles some information on how kids circadian rhythms change during adolescence, and advocates for later school starting hours.

He points out the interesting concept of chronotypes:

Everyone, from little children, through teens and young adults to elderly, belongs to one of the ‘chronotypes’. You can be a more or less extreme lark (phase-advanced, tend to wake up and fall asleep early), a more or less extreme owl (phase-delayed, tend to wake up and fall asleep late). You can be something in between – some kind of “median” (I don’t want to call this normal, because the whole spectrum is normal) chronotype.

— Zivkovic (2012): When Should School Start in the morning in Scientific American (blog).

And how your chronotype gets phase-delayed at puberty:

No matter where you are on these continua, once you hit puberty your clock will phase-delay. If you were an owl to begin with, you will become a more extreme owl for about a dozen years. If you are an extreme lark, you’ll be a less extreme lark. In the late 20s, your clock will gradually go back to your baseline chronotype and retain it for the rest of your life.

— Zivkovic (2012): When Should School Start in the morning in Scientific American (blog).

A Better Commencement Address

2. Some of your worst days lie ahead. Graduation is a happy day. But my job is to tell you that if you are going to do anything worthwhile, you will face periods of grinding self-doubt and failure.

— Wheelan, 2012: 10 Things Your Commencement Speaker Won’t Tell You in The Wall Street Journal

Charles Wheelan provides an excellent perspective on what should be important in a commencement address.

I particularly like this warning about the danger of working only for rewards:

8. Don’t model your life after a circus animal. Performing animals do tricks because their trainers throw them peanuts or small fish for doing so. You should aspire to do better.

— Wheelan, 2012: 10 Things Your Commencement Speaker Won’t Tell You in The Wall Street Journal

And this point on conservation and the real meaning of being conservative:

3. Don’t make the world worse. I know that I’m supposed to tell you to aspire to great things. But I’m going to lower the bar here: Just don’t use your prodigious talents to mess things up. Too many smart people are doing that already.

— Wheelan, 2012: 10 Things Your Commencement Speaker Won’t Tell You in The Wall Street Journal

The Dish

Radiation dosages

Radiaton dosages from different sources. Graph by http://xkcd.com/radiation/.

xkcd has published an excellent graph showing where different dosages of radiation come from and how they affect health. It’s a complex figure, but it’s worth taking the time to look through. I find it easiest to interpret going backward from the bottom right corner that show the dosages that are clearly fatal.

One Seivert (1 Sv).

One red square of 100 red blocks is equal to one seivert, which is the radiation dosage that will kill you if you receive it all at once. Note:

  • If you were next to the reactor core during the Chernobyl nuclear accident, you would have gotten blasted by 50 Sv.
  • 8 Sv will kill you, even with treatment.
  • Getting 0.1 Sv over a year is clearly linked to cancer.
  • One hour on the grounds of the Chernobyl nuclear plant (in 2010) would give you 0.006 Sv.
  • Your normal, yearly dose is about 0.004 Sv, just about how much was measured over a day at two sites near Fukushima.
  • Eating a banana will give you 0.000001 Sv.

While I did not find equivalent exposure levels, the nuclear bombs dropped on Hiroshima and Nagasaki lead to many deaths and sickness from radiation created by the explosions. Within four months, there were 140,000 fatalities in Hiroshima, and 70,000 in Nagasaki (Nave, 2010). The Manhattan Engineer District, 1946 report describes the radiation effects over the first month:

Radiation effects for the month following the dropping of the nuclear bombs on Nagasaki and Hiroshima. (Table from The Manhattan Engineer District (1946) via atomicarchive.com).

The effects were not limited to the explosion itself, though. There is one estimate, that 260,000 people were indirectly affected:

Radiation dose in a zone 2 kilometers from the hypocenter of the atomic bomb was the largest. Also, those who entered the city of Hiroshima or Nagasaki soon after the atomic bomb detonation and people in the black rain areas were exposed to radiation. … some people were exposed to radiation from black rain containing nuclear fission products (“ashes of death”), and others to radiation induced by neutrons absorbed by the soil upon entering these cities soon after the atomic bomb detonation.

— Hiroshima International Council for Health Care for the Radiation Exposed (HICARE): Global Radiation Exposures.

HICARE also has a good summary of what happened at Chernobyl, where 31 people died at the time of the accident, about 400,000 were evacuated, and anywhere between 1.6 and 9 million people were exposed to radiation. Modern pictures of the desolation of Chernobyl are here. The Wikipedia article has before and after pictures of Hiroshima and Nagasaki.

Nix the Monster

A recent study making the news today, warns about the risks of energy drinks. 30-50% of adolescents and young adults drink them, they have lots of caffeine and other additives, and they do not have a whole lot of benefits.

Energy drinks have no therapeutic benefit, and many ingredients are understudied and not regulated. The known and unknown pharmacology of agents included in such drinks, combined with reports of toxicity, raises concern for potentially serious adverse effects in association with energy-drink use.
–Sara Seifert et al., 2011: Health Effects of Energy Drinks on Children, Adolescents, and Young Adults

Applying the precautionary principle might be in order.

Sex. Ed. on TV update

The National Campaign to Prevent Teen and Unplanned Pregnancy has recently issued a report showing that teen pregnancy dropped by 6% in 2009. They have some evidence that the TV show “16 and Pregnant”, which I’ve mentioned before, is one of the reasons why.

Among those teens who have watched MTV’s 16 and Pregnant, 82% think the show helps teens better understand the challenges of teen pregnancy and parenthood and how to avoid it.
Albert (2010)

Of course, it’s essential to note that, “Teens (46%) say parents most influence their decisions about sex.”

The report has many more details.

Sex. Ed. on TV

The message — that babies and parenting are hard work — seems to be sinking in for some of its intended audience. [15 year olds] Leslie, Miguel and Paola all intend to be parents, but, as Miguel says, “not at this age.” – Grigsby Bates, 2010.

NPR’s Morning Edition had a story on “Teen Mom” and “16 and Pregnant”, two TV shows from MTV. These shows apparently offer a very realistic take on what it means to be a teen parent. So much so, the Kaiser Family Foundation is providing free DVD’s of the 16 and Pregnant series (as well as the Think HIV: This Is Me documentary).

I have not seen either of these series, but am interested in finding out if any of my students are familiar with them, if they’re appropriate for early adolescents, and if anyone else has tried them. From the radio program it sounds like they might be a useful supplement to the Baby Think It Over® infant simulators.

On a somewhat tangential note, every time is see the Baby Think It Over dolls, I’m reminded of Elna Baker’s story, Babies Buying Babies (see Act 3), on This American Life. It’s about the choices parents make when choosing the race of a life-like, newborn doll for their kids. The Baby Think It Over dolls are pretty life-like and I’ve heard anecdotes of kids getting strange looks when walking around, not just with a baby, but one that looks like it’s from a different race.

Making pectin

Extracting pectin for making jelly does not seem to be that hard. Sam Thayer has a nice little article on how to get pectin from apples. The blog Spain in Iowa, has some nice pictures and video of how they extracted pectin from apples and what the result should look like when you test it by putting a teaspoon of pectin into a teaspoon of rubbing alcohol. Almost immediately (but leave it in for a minute), the pectin should jell in the rubbing alcohol and you should be able to pull it out using a fork.

Basically, all you do is chop up the apples, cook them for a long time over low heat till they’re broken down, and then strain out the liquid produced. Since I have access to a lot of green apples that won’t be used for anything else, I tried the process myself. Using a pot full of apples I produced a lot of liquid; way more than I could ever use, but the process seems to work fairly well.

One 8 quart pot of apples produced 8.75 cups of liquid. I’d planned to use the home-made pectin in my currant jam, but testing the currant juice showed that it had just as much, if not more pectin than my boiled apple residue. I guess I’ll save the apple pectin for future use.

Ideally, Student Run Businesses should sell goods or services that are worth the value paid. While I appreciate that there is some value to the sympathy of friends and family, it is nice when customers believe they’re getting a good deal even without that. One direction I try to direct the students is toward making things from scratch, because it adds so much to the experience. Then they can have the extra value of using natural, perhaps even organic, ingredients and satisfying Michael Pollan’s rules for good eating.

In Defence of Food by Michael Pollan

My students have not yet tried jam or jelly-making, but if they do natural pectin would be great.