The Earth’s crust contains arsenic, a naturally occurring substance. Arsenic exposure, which is often caused by contaminated water and food, can have a variety of negative health effects, including cancer.
Arsenic is a serious public health problem. According to a 2020 study, arsenic contamination in drinking water is affecting up to 200,000,000 people worldwide. This level of exposure exceeds the HTML1 limit set by the U.S. Environmental Protection Agency (EPA) and the World Health Organization (10 parts per billion HTML1). Over 70 countries have been affected. These include the United States of America, Spain, Mexico and other countries such as India, China, Canada.
We believe that arsenic is a public health problem in many countries. This issue requires immediate action. We are studying the way arsenic exposure can cause cancer by forming cancer stem cells.
In the U.S., communities of color are disproportionately affected by arsenic contamination in their water.
Food and water contamination with arsenic
The body can absorb arsenic through several routes, including inhalation, skin contact, and other methods. The most common way to get arsenic is by drinking contaminated water or eating contaminated food.
Those who live in areas where arsenic levels are naturally high in soil and water, or have a natural tendency to be higher are at heightened risk. For example, in the United States, this includes the Southwest, including Arizona, Nevada, and New Mexico. Human Activities like mining and agriculture may also cause arsenic to be present in water and food sources.
Arsenic is also found in foods and drinks, as well as rice. Consumer Reports investigated in 2019 and found that certain brands of bottled waters sold across the U.S. had arsenic levels that exceeded the legal limits. Multiple studies also revealed that arsenic levels in some popular brands of baby food were much higher than legal limits.
Cancer stem cells and arsenic
Arsenic exposure can increase the risk of multiple cancers.
Arsenic’s cancer-causing mechanisms are complex and still not fully understood. Research suggests arsenic may damage DNA, interfere with cell signaling pathways, and affect the immune system. All of these can lead to cancer.
The left image shows normal ovarian epithelial cell growth. The cells on the right are shown after three weeks of chronic exposure to arsenic at 75 parts per trillion. Cristina M. Andrade Feraud/Azzam Laboratory, FIU, CC-BY-NC-ND
Scientists also link chronic exposure to arsenic with the development of tumor stem cells. They are believed to be the cells responsible for spreading and growing cancer. Cancer stem cells, like normal stem cells within the body, can be transformed into a variety of different cell types. Unknown is the stage at which a stem cell acquires a genetic mutation that changes it into a cancerous stem cell.
The goal of our research is to determine which type of cells arsenic targets in order to form cancer stem cells. We use cell cultures from the same organ at different stages of development to investigate how the origins and characteristics of the cells influence the formation of cancerous stem cells.
To reduce the health effects of arsenic, it is important to prevent chronic arsenic. It is necessary to conduct further research to better understand the formation of cancer stem cells by arsenic and to develop effective prevention strategies. Until then, monitoring and regulating this toxic metal found in water and food sources can help improve the health and wellbeing of the affected communities.