A new study reports that about 19.6 million people in China could be exposed to arsenic-contaminated drinking water, thus increasing their risk for arsenic-related diseases such as cancer and heart disease.
Researchers from Switzerland and China reviewed geological maps of the country, which provided them with information about climate, land use, rivers, and elevation. With this data, the researchers found types of rocks that are present in the land and were able to point out areas where arsenic is most likely to be found. In order to complete a full and accurate test, however, researchers will need to test nearly 10 million drinking wells throughout China, which could take decades.
Since the 1960s, China has had a problem with both arsenic- and fluoride-contaminated drinking water. Arsenic-contaminated water has been an issue in several parts of the globe, particularly in Bangladesh, where the World Health Organization (WHO) has labeled it as a “public health emergency.”
Consuming drinking water adulterated with arsenic could lead to neurological disorders, diabetes, and cancer, while excessive fluoride may be associated with arthritis and tooth loss.
Arsenic is a metallic element that is naturally present in the Earth’s crust. However, if it comes into contact with groundwater and drinking water, usually by flowing through arsenic-rich rocks, it can lead to arsenic poisoning and other chronic health issues. In a report detailing the exposure and health effects of drinking arsenic-contaminated water, the UN noted that initial short-term effects of acute arsenic poisoning would start out with a metallic taste, burning lips, and violent vomiting — followed by multi-organ failures and death.
Long-term exposure to lower levels of arsenic, meanwhile, has been associated with cardiovascular disease, as well as skin problems like pigmentation changes and skin cancers.
The study attempted to measure the number of people with the risk of drinking arsenic-contaminated water by using the threshold of 10 micrograms per liter, which is the WHO guideline and the current Chinese standard for drinking water.
"What it is very important to do is to go to the areas that are hotspots and screen those first. The chances are you will find more contaminated wells than wells that are not contaminated," noted Dr. Annette Johnson, from the Swiss Federal Institute of Aquatic Science and Technology and co-author of the study.