MUT Research Professor dissects sources and impact of radiation through a seminar

Professor Theo Davies

A picture of children playing in the dumpsite is an unusual occurrence. But for professionals like Professor Theo Davies, a Research Professor at the University’s Faculty of Natural Sciences, such a picture may signal questions about the lifelong impact of playing in that site for the children in question.

On 12 December 2022, Professor Davies, a co-founder of Medical Geology, delivered a virtual seminar where he talked at length about the negative effects of energies that emanate from mining and milling centres. The topic of the seminar was “Combating neonatal, maternal and child deaths from ionising radiation exposure around gold and uranium mines in South Africa: A Medical Geology perspective”.

Professor Davies’ presentation aimed “to reveal knowledge gaps on aspects of ionising radiation exposure of mainly pregnant women and children living around uranium and gold mining and milling centres in Sub-Saharan Africa”. Professor Davies, a seasoned researcher, also said he wanted to enable researchers in the field of Medical Geology and allied fields to gather pertinent data, that would be used to formulate novel, multipronged and proactive approaches to bridge the gaps. He also wanted to provide various stakeholders with the requisite information upon which evidence-based interventions could be predicated, he said.

Professor Davies focused mainly on radiation as a byproduct of these economic activities. He defined radiation as the energy that comes from a source and travels through some material or space. Light and heat are types of radiation, Professor Davies explained. In his presentation, he discussed ionising radiation because it has enough energy to remove an electron from an atom, making that atom an ion.

According to Professor Davies,  sources of radiation include medicine, the nuclear industry, radon gas, buildings/soils, cosmic, food and drinking water, and natural radioactivity.

Explaining how humans take in radiation, Professor Davies said that people swallow or breathe in radioactive materials, or when radioactive materials enter the body through an open wound or are absorbed through the skin. Some types of radioactive materials stay in the body and are deposited in different organs.

He explained that radiation harms humans. Radiation can damage the DNA in human cells, he said.

“High doses of radiation can cause Acute Radiation Syndrome (ARS) or Cutaneous Radiation Injuries (CRI). High doses of radiation could also lead to cancer later in life,” said Professor Davies.

Professor Davies also said that radiation can also affect pregnant women through prenatal radiation exposure.

“This can occur when the mother’s abdomen is exposed to radiation from outside her body. Also, a pregnant woman who accidentally swallows or breathes in radioactive materials may absorb that substance into her bloodstream. From the mother’s blood, radioactive materials may pass through the umbilical cord to the baby or concentrate in areas of the mother’s body near the womb (such as the urinary bladder) and expose the foetus to radiation,” said Professor Davies.

Professor Davies said the possibility of severe health effects depends on the gestational age of the foetus at the time of exposure and the amount of radiation it is exposed to.

“Unborn babies are less sensitive during some stages of pregnancy than others. However, foetuses are particularly sensitive to radiation during their early development, between weeks two and 18 of pregnancy,” he said.

He said the health consequences can be severe, even at radiation doses too low to make the mother sick. Such consequences can include stunted growth, deformities, abnormal brain function, or cancer that may develop sometime later in life.

Other common health effects or harmful effects of radiation on the human body are loss of hair, and the functioning of the heart if radiation exposure is from 1000 to 5000 rems. Radiation can also affect the thyroid, the blood system and the reproductive tract.