18 April 2008

Canada moving to ban BPA

Canada Likely to Label Plastic Ingredient ‘Toxic’
I've talked about this before, and I basically came up with, "Eh, we're poisoning ourselves anyway." So now the Canadian government is taking steps to ban BPA.

The public and industry will have 60 days to comment on the designation once it is released, setting into motion a two-year process that could lead to a partial or complete ban on food-related uses of plastics made using B.P.A.
This is the sort of thing that takes time; there are plenty of industry groups that are going to want to talk the Canadian government's ear off. But ultimately, the health of the people and the environment will hopefully win out.

Jack Bend, a professor of pathology at the University of Western Ontario in London and one of the Canadian government’s outside scientific advisers, declined to comment on what action Health Canada would take. But he said he was concerned about the widespread use of B.P.A.

“The first thing is that it’s an endocrine disrupter, there’s no question about that,” Professor Bend said, referring to the chemical’s impact on the hormonal system. “Should people that are exposed to these low levels of this chemical be outrageously concerned? I’d err on the side of not creating panic. We simply don’t know. But we should find out.”
We seem to be quite good at letting one part of science get far ahead of other parts. We make chemicals and integrated them into our lives before we have even scratched the surface of how the chemicals will effect our bodies or other living things. Rachel Carson's Silent Spring really got us moving on looking closer at the environmental impacts of the chemicals we put out there. But the closer we look, the worse it seems to get. Dioxins in Vietnam, PCB's in polar bears, endocrine disruptors in hermaphroditic fish and on and on and on.

Maybe I'll use my liter Nalgene to hold knitting needles. Oh, and I like that the NYT used the same picture in both articles.

UPDATE: Nalgene has decided to drop BPA containing plastics from their production line. They didn't go so far as to say that BPA was dangerous, but said that consumers would prefer plastics without BPA. NYT notes that the canning industry says that there is no replacement for their use of BPA. I don't buy that for a second.

12 April 2008

How graphs can lie to you

I want to discuss graphs for a bit. When we were wee first years at college, we spent a fair amount of time talking about how to make graphs well. Anyone can make a graph in Excel, but you need some knowledge to choose the right graphs for the right sets of data. You need to know when you need error bars and how to choose the right size error bars. Scale is an important aspect as well. Have a look at these two graphs.



This screen capture was taken Friday night, little before 7 pm central time.

The two graphs set the front runner as the whole and the other candidates as portions of that whole. No matter how many people are added, Obama and McCain stay as 100% of the available graph. But the more important issue is that it makes it look like Obama and McCain have the same amount of support, and that Hillary is way behind McCain. Thats part of the reason I started making my own graphs.

This graph is linked to the data on my google spreadsheet, it will update.

This graph puts all six of the candidates that ABC/Facebook is tracking on the same scale. Its pretty clear how huge of a lead Obama has among the Facebook crowd. Its also clear that Hillary is actually ahead of McCain by about 35,000 people, but thats rather hard to see since the difference is much smaller relative to Obama's lead.

So when you see a graph, look for the scale and just because two bars look the same doesn't mean that they're the same value.

08 April 2008

Pawlenty shows no love for St. Paul

St. Paul officials: What does Pawlenty have against us?

Governor Tim Pawlenty signed the bonding bill, but not before using the line item veto to cut $208 million in projects, many of them in St. Paul. But wait, St. Paul is hosting the RNC later this summer and Pawlenty's name has been floating around as a possible veep pick. Is it really such a good idea for Pawlenty to write St. Paul out of the bonding bill, when the city is about to go on display for the national convention of Pawlenty's own party?

"What does the governor have against St. Paul? What have we done?," (Sen. Sandy) Pappas asked.

"This is just a blatant attack on St. Paul and its residents, I think, and on Alice Hausman and her constituents," added (Sen. Ellen) Anderson.

DFL Rep. Alice Hausman is the lead bonding negotiator for the House and is from St. Paul. She attended the governor's briefing, but left before it ended.
There are a few things from the back story to keep in mind; the reason we have a bonding bill that is such a big deal is because Pawlenty made a "No New Taxes" pledge, and Pawlenty had said before that it was too big earlier, so the partial veto is not unexpected. Its the way St. Paul was singled out that is surprising people. The phrase bandied about this evening was a paraphrase of the New York Daily News; "Pawlenty to St. Paul: Drop Dead"


You know, that third headline might not be that far off from the current situation...

07 April 2008

La Nina doesn't negate climate change

Global temperatures 'to decrease'
La Nina is once again going lead to cooler temperatures this year but that doesn't mean that the earth isn't warming overall.

"When you look at climate change you should not look at any particular year," he (The World Meteorological Organization's secretary-general, Michel Jarraud) said. "You should look at trends over a pretty long period and the trend of temperature globally is still very much indicative of warming.

"La Nina is part of what we call 'variability'. There has always been and there will always be cooler and warmer years, but what is important for climate change is that the trend is up; the climate on average is warming even if there is a temporary cooling because of La Nina."
But just you wait, the Republicans and other climate change deniers will seize on this summer's cooler temperatures to tell us again that anti-business liberals are just making this up. Michelle Bachmann will come up with something about how its all just made up by the CFL manufacturers.

Now I don't expect all of my elected officials to understand the quantum physics behind how CO2 converts infrared radiation to heat (I only just understand it), but I do expect them to be humble enough to not blow their mouths off about things they really don't understand. In my more cynical moments I'm sure that the strong ego and thick skin needed to run for national office kills off any naturally occurring humility that might be in them.

Enough of that, back to the science. La Nina and El Nino, as Jarraud says, are natural variations. Global warming and the resulting climate change are long term changes due to levels of CO2 in the atmosphere that don't seem to have occured in the past 400,000 years. (For a sense of scale, the last ice age ended 12,000 years ago.) My question is how are the El Nino and La Nina events changing as the global mean temperature rises? How the ocean temperatures will change as the air temperature changes is not clear. Will the Pacific Ocean be even warmer in El Nino and even colder in La Nina, or will the difference get smaller so that the effect gets smaller? Or will the events happen more often?

The problem we run into here is how far back our data goes. We've got air temperature readings in the US going back to the Civil War, but we've only been taking satellite readings of the temperature of the oceans for a few decades at most. We just don't know exactly whats going to happen, we have more questions than answers, and I have to admit that it scares me sometimes.

04 April 2008

Where do your drugs come from?

In our household, we take our prescriptions to a locally owned pharmacy, one of the last in the area I'm sure. But we need to look further back; a few weeks back there was a contaminant found in the popular blood thinner heparin called attention not just to drugs made in China, but to what the actual chemicals are derived from. In the case of heparin, the answer is pig intestines, and the pictures of Chines peasants cleaning pig intestines in their homes has made some people think.

Seeking Alternatives to Animal-Derived Drugs

Before we genetically modified bacteria to take over the job many drugs were made from animal products, insulin and growth hormones to name just two. But some things just don't transfer well, and heparin is actually a mixture of disaccharides and just one doesn't work the quite same as all of them together. That makes the synthetic version, with only one of the disaccharides, more expensive and less effective.

“Any time you take a tissue or an extract process from a tissue from one species and put it into a another species or even another animal, you run the risk of unwanted pathogens that you didn’t know were there; that’s been responsible for repeated problems over the course of time,” Dr. Brown said. “If you can do something without taking tissue or a product from another being, you’re ahead of the game.”
Specifically they discuss the threat of prion disease, like mad cow but from pigs. With chemicals that are extracted, you don't have to worry about rejection because, hopefully, its pure enough to not have anything that would provoke an immune response.

But the article doesn't focus on heparin, but rather on the enzymes that people with cystic fibrosis need to live and digest food properly. A pharmaceutical company is working on a process that uses microbes rather than pigs to produce the enzyme, much like insulin is now, but its not finished yet.

“You don’t ever know what’s going to happen to pigs,” said Dr. Campbell of the Cystic Fibrosis Foundation. “We wanted redundancy in the system and a backup. If there was a recall of these products for six months, a number of people would die.”
Thats what it really comes down to, redundancy. If there is only one source, that source could be animal, vegetable or mineral, a recall is a recall. Thats another reason pharmaceutical monopolies are bad, if one company goes under, has their plants shut down, or relies on the same tainted Chinese manufacturers, there are humans that would suffer for lack of their drug.

02 April 2008

Just in case you weren't sure...

Its true, I'm a huge nerd. This graph I made tracks support of the major candidates based upon the Facebook/ABC US Politics application. I record the data using Google documents over my lunch break, but I also have an Excel file on my computer that I update in the evening.

There are a couple things that I find interesting. The first few are in the raw numbers; Obama has a commanding lead, Paul has a strong contingent, and McCain only broke one hundred thousand supporters last week. The next few interesting things are in the change in support from one day to the next. McCain gains more people per day than Clinton. The day after Gravel announced he would seek the Libertarian Party's nomination, he started gaining supporters. For awhile there, the net gain of people for all three Republican candidates was less than McCain's because Huckabee was loosing so many supporters. The next interesting thing is on sheet two, each candidate's daily gain of support as a percentage of the net gain. Obama's daily gain is consistently sixty to seventy five percent of the daily gain. He is gaining more people than everyone else combined every day.

Now the graph of Change in Support will, I think, be more interesting as the sample size increases. But for now I think it just shows that less happens on Sundays.

The thing to keep in mind is that this is far from a representative sample of Americans, and probably not even a great sample of young Americans. Facebook started as a site for college students with a valid .edu email address. While it has become an open site, I don't think it would be unfair to guess that it still skews toward the college student. Plus, the people who have this application and have used it to show support for a particular candidate probably care about national politics a bit more than the general population.

So if this isn't a representative sample, is it really that interesting? I think so and not just because I made it. It does show that there are at least a million people who have gone out of their way (but not terribly far) to show their support for a candidate for president. Will this translate into votes? Votes by young people? I don't think you can tell that from this data. Especially since there really isn't anything like it to compare it to.