Human health risks from oil pipeline spills

October 9, 2011

Oil pipelines have been in the news a lot this past year, between the proposed Keystone XL pipeline and various publicized oil spills. Potential human health effects of these spills are one of the concerns frequently raised, so I’m going to take a fairly high-level look at the potential risks here. Environmental effects are a separate topic that I’ll hopefully get to in the future.

First off, to have a human health risk, you have to have a few conditions met. The first is obviously that you have to have a potentially harmful chemical. Since any chemical, whether natural or synthetic, is potentially harmful at some dose, that one is kind of a given. The second condition is that chemical must get to where humans can be exposed. The third is that humans have to be exposed to enough of the chemical to have a potential for adverse health effects.

When oil is inside a pipeline there isn’t really any potential for exposure. So what happens when oil is released during a pipeline rupture?

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Sometimes the good guys win

August 26, 2011

Canadian Blood Services was running a campaign called “What’s Your Type” that included providing all sorts of weird new-agey mumble-jumble about blood types being related to personalities and recommended diet. They also had incorrect information about the origin of the different blood types. After word spread around the blogosphere a lot of people complained (including me), since an agency like that shouldn’t be providing false information, even if they did have a tiny disclaimer at the bottom that it was for “entertainment purposes only”. This has resulted in the nonsense being taken down, and replaced with a page indicating that they’ll determine your blood type for free. So yes, we can make a difference.

In case anyone is wondering, yes, I do plan to get back to talking about actual science in the near future. We get about two months a year of nice weather here, so I’ve been trying to enjoy the outdoors as much as possible before going back into winter hibernation mode. On top of that I’ve recently agreed to take on a new teaching gig on the side (as if I didn’t have enough on my plate already) and am trying to get everything ready before the semester starts in September. I should be able to get to some more substantive posts soon though.

Cadmium – the new lead?

July 26, 2011

Health Canada has just proposed a limit on cadmium in children’s jewelry of 130 ppm (0.013%), which is lower than the limit for lead concentrations. This limit was imposed because after a limit was established for lead, manufacturers started using cadmium instead. Several pieces of jewelry tested over the last couple of years have been almost pure cadmium, but in most cases these items remained on the market because there is currently no regulatory mechanism by which Health Canada can force them to be recalled and the sellers refused to voluntarily recall them (and yet there is still a lot of political resistance to proposed regulations that would give Health Canada the power to force a recall…).

So what’s the concern with cadmium, and is it really more toxic than lead? Read on…

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Salt consumption and the media

July 21, 2011

A good post at Science-Based Medicine today about how the media managed to completely misinterpret a meta-analysis of studies on salt effects.

Yes, I’ve been pretty slack about posts lately – summer is pretty short here so I should spend the time outside rather than sitting at my computer.

Cell phones and cancer – revisited

July 4, 2011

ResearchBlogging.orgA few weeks ago the classification of radiofrequency electromagnetic fields (RF-EMF, the radiation from cell phones) as a possible human carcinogen by the International Agency for Research on Cancer (IARC) made headlines. At the time, my position was that it is hard to draw conclusions from a press release, but that given the criteria for classification as a possible human carcinogen, the information in the press release and the data available in the scientific literature I didn’t see a need to panic.

Now more technical information about the IARC evaluation is available, published in the Lancet; while it still isn’t the full IARC technical monograph (which we probably won’t see for several months at least) it does provide a bit more insight into the basis for the IARC classification. At virtually the same time, another analysis of the same data by the International Commission for Non-Ionizing Radiation Protection (ICNIRP) Standing Committee on Epidemiology has been published, which concluded that “the accumulating evidence is increasingly against the hypothesis that mobile phone use can cause brain tumours in adults.” Which of these two apparently conflicting conclusions should we believe? Read the rest of this entry »

Classification of formaldehyde as a human carcinogen

June 20, 2011

There have been a few reports in the news recently about how the US government has added formaldehyde to their list of substances known to cause cancer in humans. This doesn’t really come as a surprise – the International Agency for Research on Cancer (IARC), for example, already classifies formaldehyde as a confirmed human carcinogen. But since there’s some media attention on the subject right now, and since formaldehyde exposure can occur from a variety of sources, including many consumer products, it seems a good time to look at what this classification means for the general public.

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Methylmercury and fish consumption

June 9, 2011

After a bit of a break, I’m getting back to my series of posts related to mercury. This time I’ll focus on methylmercury, which is generally considered to be one of the “nastier” forms, since it is relatively toxic (primarily neurotoxicity, but also believed to cause cardiovascular and reproductive toxicity at high doses) and also bioaccumulates in animals. Since the main source of methylmercury exposure is food, and in particular fish, I’ll look at how the amount of mercury in fish relates to potential effects on humans.

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