In the previous post, it was noted that Busby's claims about a deviating sex ratio in Fallujah (first article here, second article here) may not be such a significant finding as he makes it sound, and that Busby is well aware of it but doesn't change his approach about it. There are weaknesses in the study, both methodological and due to the difficult circumstances in performing the study. So, in lack of other data, the results of the study may be of interest, and if properly designed the survey may give much better results than other kinds of surveys. But with the weaknesses in mind it would be reasonable expect a more humble approach from Busby and co-authors about the conclusions, if they are serious about it, that is.

One of Busby's most significant findings, according to himself, is the deviating sex ratio for the children born in the years after 2004, the year of the battle of Fallujah. The first study shows a decrease in the number of boys with respect to the number of girls, 18% below the normal level (860 boys to 1000 girls instead of the expected 1055 boys to 1000 girls). According to Busby this must be due to mutagenic stress induced by radioactivity from uranium. To support this theory he cites studies about lower sex ratios when the parents have been exposed to uranium in mines, medical radition treatment, and the Hiroshima bomb. So if we ignore the weaknesses of the study, we may agree with Busby that an 18% reduction in the number of boys born is interesting.

The problem is that he consistently ignores all other possibilities. The wikipedia page on human sex ratio gives a number of environmental and sociological reasons for deviations in the sex ratio. Busby does not mention a single one of them. Considering the heavy fighting in the city, there may also be further reasons for deviations, including stress and the simple fact that maybe people are not putting priority on making babies when their homes and a good fraction of the city (and the country) have been smashed into rubbles. The issue about if uranium based weapons were used at all in Fallujah is an open question, there are opposing views on this issue (it has surely been used in other parts of Iraq). If we assume that uranium based weapons were used, then we would expect Busby to at least mention the known chemical toxicity of uranium. Instead he puts all emphasis on the radioactivity from uranium, his theories about radioactivity is the only thing that matters for this self-proclaimed international expert on radiation.

Considering how many attempts Busby has made with epidemiological studies (and failed badly with some of them) it is quite remarkable that he still has not learnt to be cautious with the most important parameter: low statistics. Furthermore, with all the possible reasons that he excludes as potential causes, he never asks the question: Is a deviation in sex ratio always due to mutagenic stress from radioactivity? It is always due to mutagenic stress at all? Let's find out.

As noted in an earlier blog post, Busby is quite upset with the Swedish Health Authorities (Socialstyrelsen) for not letting him use their cancer statistics data base, apart from the data that are publically available and that he already mistreated last year. I have some good news for him, he can play with another data base, the one from Statistics Sweden (Statistiska Centralbyrån, SCB), which has a lot of interesting data on the Swedish population. Let us use this data base in order to check the sex ratio for a few cases. Let us start with checking the sex ratio for the entire population in Sweden, i.e. the number of born boys every year divided with the number of born girls every year. As in Busby's article we normalize to 1000 born girls and expect the sex ratio to be around 1055.

Sex ratio for Sweden during the time period 1968-2010. Source: www.scb.se

We see that the sex ratio is indeed very close to 1055, the average rate is 1058. And it fluctuates very little, it is always well within the span 1040-1070, with minor statistical deviations. But we have lots of statistics when we use the number of born children in entire Sweden. So let us look at the same situation for a medium sized city in Sweden, for instance Avesta, the city where I was born. We use a blue line for the sex ratio for each year, and a red line for the 5-year average:

Interesting fluctuations indeed! Busby has made a lot of fuss about the level 860 boys to 1000 girls. This in a total cohort of 4843 persons. The population of Avesta is more than 21 000, so we should have more than enough statistics in order to make a fair comparison and even err on the side of caution. We see that the sex ratio (blue line) fluctuates year by year around the expected value of 1055 boys to 1000 girls, though in some years the sex ratio is down to 800 boys to 1000 girls. But in the Fallujah study the data were shown as cohorts of 5-year averages. The red line shows the data for 5-year averages for Avesta. This curve does not fluctuate so drastically as the blue line, the extreme values cancel out. In spite of this we see a drastic decrease in the sex ratio for the last five years, going down to slightly less than 900. This is not as low as the value 860 in Fallujah. But it is based on better statistics, and from a trustworthy source that probably has the numbers correct down to each individual child. And to my knowledge Avesta has not been bombarded with uranium based weapons recently.

Now, can we find any city in Sweden where the 5-year average of the sex ratio at some time in the period 1972-2010 is lower than 860? In order to be fair we should set a constraint that the city should not be too small. The population pyramid in Sweden is very different from the one in Iraq, so in order to have enough children born for a fair comparison we set, arbitrarily, that we want to find a city with a population of at least 10 000, where the 5-year average of the sex ratio at some time has been below 860. Well, look:

Sex ratio for 8 Swedish cities with populations larger than 10 000 people. The Fallujah data are inserted as a thick grey line. Click on the picture for a link to a larger version.

The figure is a bit messy, but the main point is to look at the extreme values for each city. We find eight cities that fulfill the requirement of a 5-year average sex ratio that at some time is below 860. The cities are: Trosa (pop 11 492), Åtvidaberg (11 474), Mörbylånga (14 152), Burlöv (16 825), Strömstad (11 965), Filipstad (10 506), Nora (10 462) and Hedemora (15 141). The data from Fallujah are shown as a broad grey line.

Wait a minute, you may say. These cities are probably from the same region, and share some common environmental effect. Hardly, the map below show their locations in Sweden. Furthermore, the fluctuations for the different cities do not agree in time with each other. It is therefore very unlikely to find a common cause. Except low statistics, just as in the sample from  Fallujah. If we include Swedish cities with populations below 10 000 then we will find more than 30 with sex ratios below 860 in the 5-year average, some of them well below 750. The reason is, again, low statistics.

Map of Sweden, with the location of the 8 cities shown.

But what about the drastic decrease in the number of born children in Fallujah, the number of boys born went down with 50%? This must be due to an environmental effect, right? Well, not necessarily. There can be many different reasons for why there is a decrease in the number of born children, not the least after an intense battle occurring in the city. But let's take a look at the 8 Swedish cities again, now we look at the number of born boys:

The number of born boys in the 8 cities that we look at.

Once again we see that the dramatic variations in Fallujah are not extreme when comparing with some of the Swedish cities. Each Swedish city has its own behaviour, mostly depending on local variations in the population. But most of them share a common drop from a peak value around the year 1992. For Hedemora the number of born boys is reduced to almost 50% over a ten year period, with 35% decrease as the most dramatic drop over a 5-year period. But why is there such a decrease in most of the studied cities? Well, let's look at the number of born children for all of Sweden:

Number of born children in Sweden, 5-year averages, 1968-2010. Source: www.scb.se

We see that there was a peak around 1992 followed by a quite drastic decrease, in 1997 the 5-year average number of born boys was 26% lower than in 1992. Is it due to the bad economy of Sweden at the time? Or was it less "popular" to have children for a couple of years? There are surely studies available regarding likely causes. Whatever the reason, we can easily exclude uranium based weapons. This does not disprove any hypothesis about uranium being the cause in Fallujah. Furthermore, I have only looked at the sex ratio while the article deals with a number of health effects, but whoever argues for uranium being the cause has a lot to explain before talking about significant findings the way Chris Busby does.

A few conclusions:

• All these cities have drastic variations in the sex ratio, even for the 5-year averages, and reach values lower than 860 boys to 1000 girls.
• For several of the cities the 5-year averages varies dramatically, similar to in Fallujah.
• The cities are distributed in different parts of Sweden with different geographical/environmental conditions.
• The periods of low sex ratio for the 8 cities occur at different times, no common cause can be seen.
• None of the 8 cities have suffered from war during the last 200 years, and during the last 40 years Sweden has been among the top ranked countries in the world when it comes to health status of the population.
• The variations are as large, or larger, than in Fallujah, based on much more reliable data, and equal or better statistics.
• Chris Busby should give up all attempts of epidemiology. This is not the first time he fails in this discipline, he just can't do it right.
• We do not learn anything about the causes of the health effects in Fallujah by listening to self-proclaimed experts like Chris Busby.

There are indeed more things to say about Busby's studies on Fallujah. When time permits they will be brought up on this blog.

Mattias Lantz - member of the independent network Nuclear Power Yes Please

Related blog posts:

Chris Busby and the Fallujah sex ratio - Part 1 (dishonesty)

Bad science - Chris Busby and his articles on Fallujah

The city of Fallujah in Iraq suffered through intense fighting during 2004, and US troops bombarded the city heavily. The US military has admitted to the use of white phosphorous, which is quite toxic though not necessarily cancerogenic. Whether depleted uranium (DU) weapons were used or not is still an open question, there is a number of statements in both directions from many different sources.

During the last few years there have been news reports about an alarming number of children born with deformities, and other serious health effects among the Fallujah population. In July 2010 a study by Chris Busby and coworkers was published in the International Journal on Environmental Research and Public health (here). The title of the article is the rather alarming Cancer, Infant Mortality and Birth Sex-Ratio in Fallujah, Iraq 2005–2009, and it reports on the results of a survey done in Fallujah that reveals drastic increases in various forms of cancer and birth defects.

The details of the study can be found directly in the paper (here), or from Busby's presentation about it in Stockholm in August 2010 that is available on Youtube (here). A transcript of what he says in the presentation and the discussion after is given here.

There are many things that can be said about the survey and the quality of it. Considering the difficulties of performing the survey, and the limitations of this kind of survey (knocking on doors and asking about the health status of the people living there), one has to be very careful and consider all the weaknesses before drawing any conclusions. Busby and coworkers cover much of these concerns in section 2.3 of the article; Strength and Weaknesses. It says, among other things:

One weaknesses of this type of study is population leakage due to migration. Although ten years is used on the questionnaire, from analysis in earlier studies of this kind [7] it has become clear that there is leakage of cases (due to deaths and subsequent population movements) and so the recent five year period is employed.

In other words, if the survey gives the result that 100 people in a population of 1000 suffer from a certain disease, giving a rate of 10%, it means that the actual rate can be different due to the fact that some of the people suffering from the disease may have died or moved away before the survey was done. This makes sense, but then there is a strange passage:

However, as a consequence of such a population leakage it is clear that the result will show the minimum cancer rates existing in the study group. In earlier studies this effect was especially found for lung cancer which has a high mortality to incidence ratio.

This part is not so obvious. Of course, if the people who died or moved away suffered from the same disease, the rate would be higher if they had still been alive and had participated in the survey. But it could also be the opposite, the people who died or moved away did not suffer from the same disease, and if they were still alive and participated in the survey the rate would be lower. So, if the disease we are looking at has a high mortality rate, as in the case with lung cancer, then the assumption may be reasonable, depending on how many people that have moved away or died of other causes. Clear it is certainly not.

Another interesting thing is that, while Busby and co-authors in the article are very careful about not stating that uranium is the cause of the health effects, Busby has no qualms about laying out the words in other places. For instance, in the Green Audit report where he claimed that 10 tonnes of enriched uranium had leaked from the Hinkley Point nuclear power plant, he puts them together without further explanation:

Most recently, alarming increases in breast cancer, leukaemia, childhood cancer and congenital malformation/infant mortality increases were found in Fallujah, Iraq, a city where uranium weapons were employed and uranium particles will have been inhaled (Busby et al 2010).

So even though the original paper does not show any connection between uranium and the health effects, he makes it sound like there is an obvious connection when he refers to the paper in other works.

Well, let's move on. In section 2.5 of the article the sex ratio is defined in one line as:

The population data in 5-year age groups was used to examine the sex ratio in 5-year birth cohorts.

In section 3, which covers the results of the survey, we read the following regarding the sex ratio:

The responses show that there is an anomalous sex ratio in the 0–4 age group. There are 860 males to 1000 females, a significant 18% reduction in the male births from the normal expected valueof 1,055 (267 boys expected, 234 observed; p < 0.01)

860 boys to 1000 girls after the 2004 battle, this does indeed sounds serious if the normal ratio is 1055. To use Busby's own words from the BSRRW meeting:

"It is absolutely standard, and very rarely diverse at all, that number, unless there is some problem."

Chris Busby explaining the significance of the results with deviating sex ratio in Fallujah, at the BSRRW meeting in Stockholm, 10 August 2010.

But what possible reasons could there be for it? Section 3 of the paper continues:

Perturbation of the sex ratio is a well known consequence of exposure of mutagenic stress and results from the sensitivity of the male sex chromosome complement to damage (the females have two X chromosomes whereas the males have only one).

So according to Busby and co-authors, mutagenic stress is the cause of why less boys than girls are born. The text continues with an explanation of what can cause mutagenic stress (emphasis is mine):

A number have studies have examined sex-ratio and radiation exposure of mothers and fathers. Of relevance is the study of Muller et al. [10] of the offspring of 716 exposed fathers who were Uranium miners. There was a significant reduction in the birth sex ratio (fewer boys). Lejeune et al. (1960) [11,12] examined the offspring of fathers who had been treated with pelvic irradiation; at high doses there was an increase in the sex-ratio, but this reversed in the low doses (around 200 mSv). Schull et al. 1966 [13] found a reduction in the sex ratio in A-Bomb survivor fathers (mothers “unexposed”) for children born 1956–1962 a reversal of an earlier finding by Schulland Neel 1958 [14] of a positive effect in the 1948–1955 births. It should be noted that there were external and internal irradiation effects in these groups, with the internal effects predominating in the later years. Yoshimoto et al. 1991 [15] found an overall reduction in the sex ratio for A-Bomb survivors for children born 1946–1984. Thus the evidence suggests that exposure to ionising radiation at low doses and specifically exposure to Uranium may cause a reduction in the sex ratio.

The quoted references deal with uranium miners, medical radiation treatment, and radiation from the Hiroshima bomb. So, exposure to radioactivity among the parents may cause mutagenic stress, which leads to a reduction in the number of boys born. At least there were scientific reports about it during the 1950's and 1960's, five of the six references are quite old. One would expect that such a world famous radiation expert as Chris Busby should be able to back his reasoning with references that covers the development of the field until present instead of what happened more than 45 years ago. There is nothing wrong with referring to old articles, but if you only do it and ignore later developments (if they exist) then your line of reasoning may be very weak.

Regarding the low sex ratio in the case of Fallujah, could there be other reasons than uranium-based weapons? Please note that Busby and co-authors do not mention any of the studies that show a connection between deviating sex ratio and exposure to chemicals, heavy metals, smoking and other environmental effects (see for instance the Wikipedia entry on sex ratio). Busby does not even acknowledge the chemical toxicity of uranium, instead it has to be the radioactivity of uranium, if it is the cause. The authors mention depleted uranium several times, but are very cautious about drawing any conclusion regarding what is the reason. That is a wise approach considering all the uncertainties related to a study like this, and the fact that there are a number of other possible causes.

It is less wise, however, to emphasize uranium as a likely cause, or to claim that the 18% reduction of the sex ratio is significant when you are not even sure about what you have measured. During the talk at the BSRRW meeting in Stockholm in August 2010, a person in the audience, Dr. Eckerman, wanted to have a clarification of what the data really showed. After some confusion it turned out to be that the sex ratio was not derived from the number of born children, but from the number of children available at the time of the survey.

So, to repeat the quote from Busby's presentation again:

"It is absolutely standard, and very rarely diverse at all, that number, unless there is some problem."

As it turned out during the BSRRW meeting, there was indeed a problem. Not only did Busby ignore the earlier so cautious approach when he claimed that the deviation was significant, he also based the sex ratio on the wrong assumptions about the group of children.

Somehow this classic picture seems appropriate...

You may wonder what's the big fuss about? Well, if the sex ratio is to be trusted it has to be derived from the number of born children in the study group. If you instead only have data on the number of living children at the time you make the survey, then you are missing the children who may have died or moved away. Busby disqualified the method himself when I asked about the age group 5-9 years old, which seem to deviate in sex ratio in the opposite direction, i.e. there are significantly (13%) more boys than expected. To be fair to Busby, for the age group 5-9 there are more children that may have died or moved away (or moved to the city) than for the age group 0-4 years, there have been 5 more years when things can happen. But even with that in mind, it is very irresponsible of Busby to claim that it is such a significant finding, when he ignores all the weak points in his reasoning.

So all the time Busby has known that the reported sex ratio is based not on the number of born children, but instead on the number of children available at the time of the survey. The message from Dr. Eckerman is quite clear; to speculate about the causes of the deviating sex ratio should not be done without keeping the limitations of the study in mind. And if you are honest in your approach, you make a clear statement about this the next time you present the study. In spite of this, when Busby a few weeks later has a presentation about his study at the Human Rights Council in Geneva (22 September 2010) he repeats the same thing without any caveats. In fact he says:

Then most important, we found the sex ratio... [...] This is the most important result that we had here.

It seems as if he has forgotten Eckerman's objections. To be fair, he does say that there are some structural problems with the study, and that those concerns are brought up in the paper. But he gives no details about these structural problems during the talk. Instead he goes on with all sorts of explanations about the causes (including some ludicrous speculation about cold fusion based weapons!), as if they were clearly established facts. A year later all concerns about weaknesses in the study seem to be forgotten. The new article about Fallujah (Alaani et al., Conflict and Health 5:15 (2011)) starts off with the following statement in the second sentence (emphasis is mine):

In addition to the increased cancer and rates and infant deaths, the epidemiological study [1] showed that there was a sudden significant drop in the sex ratio (an indicator of genetic stress) in the cohort born in 2005, one year after the battles which occurred in the city, suggesting that the cause of all these effectsis related to the time of the US led invasion of the city in 2004.

I could buy the argument if it was phrased something like "the epidemiological study [1] gave an indication, although with large uncertainties, of a reduction in the sex ratio..." But as we have seen before it is not in the interest of Chris Busby to be clear about the details, at least not when the details make the case weaker. Instead he never misses a chance to bring it up, for instance in the RT interview from 26 October:

http://rt.com/news/uranium-birth-defects-fallujah-729/

or in the LLRC press release:

http://llrc.org/du/subtopic/fallujah20oct2011.htm

Busby has to push the line that there has been a significant change in the sex ratio, and without stating it clearly he and his co-authors do everything but saying it straight out that it must be due to uranium.

So we now have seen how Busby in writing is very careful with stating too clearly that there is a clear connection between the deviating sex ratio and some sort of uranium based weapons. In talks and interviews however, he clearly gives a different message. And he consistently ignores all other possible explanations, just as if they wouldn't even exist.

Now the question is, is the deviating sex ratio in Fallujah even relevant? We will look at this issue in part 2. Stay tuned.

Mattias Lantz - member of the independent network Nuclear Power Yes Please

Related blog posts:

Chris Busby and the Fallujah sex ratio - Part 2 (incompetence)

Bad science - Chris Busby and his articles on Fallujah