Uranium travels nerves from nose to brain

Two articles in Environmental Health News review technical reports on new discoveries about the effects of depleted uranium on the body.  In “Uranium travels nerves from nose to brain”, the author writes:

Nerves can act as a unique conduit, carrying inhaled uranium from the nose directly to the brain, finds a study with rats. Once in the brain, the uranium may affect task and decision-related types of thinking.

This study provides yet another example of how some substances can use the olfactory system – bypassing the brain’s protective blood barrier – to go directly to the brain. Titanium nanoparticles and the metals manganese, nickel, and thallium have been shown to reach the brain using the same route.

In another article, “Depleted and enriched uranium affect DNA in different ways,” the author writes:

Meticulous research identifies for the first time how two main types of uranium – enriched and depleted – damage a cell’s DNA by different methods. The manner – either by radiation or by its chemical properties as a metal – depends upon whether the uranium is processed or depleted.

This study shows that both types of uranium may carry a health risk because they both affect DNA in ways that can lead to cancer.

Why does it matter? Regulatory agencies determine safe uranium exposure based on the metal’s radioactive effects. Currently, safe exposure levels for workers and military personnel are based on enriched uranium – which is the more radioactive form and is considered to have a higher cancer risk than depleted uranium. Uranium exposure has been shown to affect bone, kidney, liver, brain, lung, intestine and the reproductive system.

Yet, many people are exposed at work or through military activities to the less radioactive, depleted form. They may not be adequately protected based on current methods that evaluate uranium’s health risks.

The study found that depleted uranium could cause genetic damage by its toxicity rather than its radiological effect:

However, the depleted uranium had a different type of effect. It altered the number of chromosomes in the cell. These effects are due to improper migration of chromosomes when cells divide. This type of damage – called aneugenic damage – was not related to the amount of radiation the cells received and was likely caused by the metal properties of uranium.

The methods used in this study clearly provide a new way to assess the different types of genetic harm caused by uranium. The findings will help ferret out whether the genetic damage caused by the depleted uranium also carries a high risk of causing cancer, which is something those who work with or are around the metal want to know. Further study is warranted to truly assess human health risks.