Arsenic poisoning linked to diabetes
by Geraldine Hinter
New research reveals that ingesting an excess of arsenic through contaminated groundwater can lead to diabetes.
Contaminated groundwater has been linked to significant ingestion of arsenic, resulting in the poisoning of people worldwide, particularly in Asian countries such as Bangladesh.
During a visit to Bangladesh, Professor Ravi Naidu of UniSA’s Centre for Environmental Risk Assessment and Remediation (CERAR) was struck by the number of people who had symptoms similar to that of diabetes. He raised a possible connection between excess ingestion of arsenic and diabetes with a number of toxicologists and doctors who confirmed a link between excessive arsenic ingestion and diabetes.
Prof Naidu is researching another possible link between arsenic poisoning and the high incidence of people with diarrhoea but so far results have not been conclusive.
"If a female has been poisoned through ingestion of arsenic, it causes a lot of upheaval in the community because the disease manifests itself as melanomas on the skin and she is labelled an outcast," Prof Naidu said.
"There is an urgent need to find solutions for arsenic poisoning as many people are suffering and millions of people worldwide are potentially at risk," he said. "Given that the majority of such impacted people are in the developing countries, the lack of financial resources has impeded the development of appropriate management strategies.
"Our research shows that water used for potable purposes is the main contributor but the use of water for the production of crops including rice has added to the problem. When people irrigate their rice or vegetables with groundwater, arsenic from the groundwater transfers to the soils and through the soils into crops."
In a significant finding, CERAR researchers have been able to determine the proportion of arsenic that is ingested from crops as opposed to water, and have ranked the different vegetables and rice into groups that accumulate excessive levels of arsenic and those that accumulate low levels of arsenic.
"What is interesting is that the concentration of arsenic in rice is not high enough to harm people but because so many people in Bangladesh and other Asian countries eat significant amounts of rice, most exceed their total daily acceptable limit of arsenic, not by a small fraction but by several times the acceptable limit. Coupled with that is the problem that most of the people come from poor countries and are not eating sufficient nutrients that they need to sustain good health," Prof Naidu said.
"We are making a major contribution to the health of the people of Bangladesh by helping the government there to produce pamphlets that show which vegetables are safe to eat and those which are not safe to eat, as well as the conditions under which people should grow them."
Prof Naidu will be going to Bangladesh later this year to see what recommendations have been adopted by the people there.
"Our scientists have worked on arsenic contamination since 1998 and have done a lot of work that has enabled us to come up with strategies to manage the effects of arsenic. We are also developing methods for cleaning up arsenic contaminated environments," he said.
"My next piece of research will be to see how closely diabetes and arsenic in water and arsenic in crops are related to arsenic levels in people’s blood, which will be done in partnership with a hospital in Bangladesh.
"Once we can demonstrate a strong predictive relationship between arsenic in water and diabetes, we can make sound predictions that ingestion of arsenic is going to lead to diabetes. To prevent that, we must get them to use other sources of water."