I’ve used the word legacy a lot when I wrote about the accumulation of lead in a lead workers body, and what that meant in terms of health outcomes.

So I’m going to start with a blog about some of what that that legacy means.

A really good place to start is with an e-book, Lucifers Curves: The Legacy of Lead Poisoning. Lucifer Curves by Rick Nevin – Ebook | Everand

Statisticians noticed that as the amount of leaded petrol used went up, the incidence of a whole lot of other things were also increasing. Things like youth violence, number of unwed mothers and so on. The fact that these things might be related didn’t register until leaded petrol began to be phased out and as the use of leaded petrol dropped, so did youth violence and so on. The rise could have been due to changes in the living conditions of people, changes in diet, other environmental factors and so on. But when the use of leaded petrol dropped, and the incidence of a whole lot of other things dropped accordingly, people noticed.

When the graphs of lead vs everything else were compared, some of the curves matched, almost perfectly. That’s what the book is all about, the sociological and other changes that matched up with the use of leaded petrol. It also has some interesting commentary about politics in the UK.

There are other interesting statistics, like the ones that came out of a relatively large epidemiological study where over 10,000 people were studied for about a decade, with regular interviews, health checks and blood tests. One significant statistic that came out of the study was that as blood lead levels went up, so did the incidence of cardiovascular disease.

Lead is a biological irritant as well as inhibiting sulphur-containing regulatory systems, and interfering with neurotransmitters. So as the effects of lead have been studied, all sorts of other parallels have been found between blood lead levels and other diseases.

I’ve talked about atherosclerosis before, and I think I’ve mentioned the finding that blood pressure increased as blood lead levels increased in former soldiers. I view soldiers as lead risk workers that aren’t working in a safety controlled work environment. They do have armoured vehicles and flak vests though, which actually puts them in a slightly better position than workers protected by RSHQ regulations at the moment, but that’s being petty.

In case there’s any doubt about the link between lead and cardiovascular disease, please read “

A prospective study of bone lead concentration and death from all
causes, cardiovascular diseases, and cancer in the VA Normative
Aging Study” by Weisskopf et al, Basic Life Science 1990,:55:267-74.

I’ll quote their conclusions:

We found bone lead to be associated with all-cause and cardiovascular mortality in an environmentally-exposed population with low blood lead levels. This study suggests that cumulative lead exposure from prior decades of high environmental exposures continues to significantly impact risk of death despite recent declines in environmental lead exposure.

The declines in environmental lead exposure refer to decline in the use of leaded petrol in the US.

Talking about the effects of lead in children will be some later blogs, but since my time on the computer is being restricted a bit (my wife!), I thought I’d bring up a few interesting stories.

Prostate cancer was relatively rare according to a surgeon at The London Hospital (J Adams) in 1853. That’s no longer the case, with a current saying: “More men die with prostate cancer than because of it”.

So something that was uncommon before the 20th century, was relatively common in 1945 is now the commonest male malignancy.

Over the years prostate cancer treatment has progressed from surgery with hideous complications, to biochemical/drug treatments and minimally invasive surgery.

There were gloriously awful incidents where the use of estrogen for example, was thought to reduce the risks of prostate cancer, and actually made things worse, but I’m wandering.

The are a lot of other possible environmental factors that could be responsible, but when researchers started looking at possible causes, they found an interesting correlation between blood lead levels and prostate cancer. That’s not totally surprising to me, not because I’m paranoid about lead (much) but because I read a report on the distribution of lead in the body at autopsy. They basically took a whole lot of tissue samples from cadavers and analyzed them for lead content. Lead in bones won the contest, followed by lead in the brain, but while high levels of lead in the aorta fitted in nicely with the link between lead and atherosclerosis, there was also quite a bit of lead somewhere else, in the prostate. That was unexpected.

The possible message is that as blood lead levels increase in older males, and even not so old males, the incidence of prostate cancer and prostate hyperplasia goes up accordingly.

After a bit more searching in the medical literature, I came across a bunch of papers that talked about the possible effects of lead on the prostate. Think about this scenario: lead causes inflammation and the tissues in the prostate respond by producing calcium deposits. I had no idea that part of the process of prostate hyperplasia was due to the deposition of calcium calculi. I guess you could call them prostate stones. The “stones” were ignored by radiologists for quite a while, but some clinicians are starting to look at ways to reduce hyperplasia and blockage of the urethra by using ultrasound, as with kidney stones. That could lead to treatments where they no longer have to ream out your urethra as it gets blocked.

While we’re on the subject of calcium, here’s a bit on the effects of lead on your bones.

Exposure to lead is associated with decreased femur and spine bone mineral density and increased risk for fracture in premenopausal women. It also significantly decreases the mineral/matrix ratio, collagen maturity and crystallinity in the trabecular bone, increasing bone turnover and resulting in weaker cortical bone.

What this means to you is that lead will weaken your bones and make them more likely to fracture. It also delays fracture healing and as a bonus it may exacerbate bone loss and osteoporosis in the elderly.

Now a bit more on the legacy lead in your bones represents.

There is a case study in 1945 (British Medical Journal) that nicely illustrates what I’ve been trying to tell you about lead in your bones being a timebomb. It concerns a 31-year-old compositor (printer/typesetter) who had been quite healthy, but he came to hospital after becoming seriously ill. In those days hospitals still routinely measured blood lead and that uncovered something totally unexpected. Serial blood tests showed his blood lead levels rising steeply from 280ug/dl on admission to 455ug/dl 2 weeks later. It was later determined that he had leukemic hyperplasia that was responsible for the release of lead from his bones. That was from lead he had accumulated in his bones working for 12 years as a compositor.

Lead in bones isn’t biologically inactive, because bone is constantly being rebuilt and the more lead you have in your bones, the higher your blood lead levels will be in the presence of further exposure to lead. If the lead is rapidly released for any reason, such as gestation, breast feeding, osteoporosis,  blood cancer or parathyroid disorders, frank lead poisoning may result.

An article in 1996 published in Environmental Health Perspectives, looked at the relative contribution of skeletal lead to lead in the circulation using lead isotope ratios. The study used blood lead and bone lead samples from lead-affected individuals undergoing total hip or knee replacement.

One of the conclusions was that:

The skeleton is an important endogenous source of lead exposure in environmentally exposed  subjects.

A last couple of depressing examples for today, and there are many more, is a direct association between lead concentration and HPV-positive cervical cancer. Plus an Australian study that showed a 7-times greater risk of oesophageal cancer as blood lead levels exceeded 30ug/dl in lead risk workers.

I made the comment that there were many examples of a link between cancer risk and lead levels. Lead in your body not only damages cells and DNA, it has a depressive effect on your immune system. So not only can lead potentiate cancer, it weakens your bodies’ immune system so you’re less able to fight the resulting cancer.

I wish I was making this up but I’m not. Why oh why don’t our Health services take lead exposure seriously and treat it like the epidemic it is?

Isn’t that a brilliant legacy. Something to look forward to when you get older?

I think I’ve pointed out a few times that lead can be removed. So if lead causes or triggers cancers, maybe they can be avoided.

It’s nearly time for me to go up and prepare breakfast for the family (tradition on Saturday mornings, I serve pancakes with fruit and whipped cream) so I’d better finish this up now.

Sorry, I really do have to finish up. More to come 🙂