A chronic bacterial infection, a flame retardant and some byproducts of water treatment processes have been added to a list of carcinogens identified in the U.S.
Eight entries have been added to the U.S. Report on Carcinogens, a cumulative report mandated by U.S. Congress to list substances that are known or are reasonably anticipated to cause cancer in humans.
In the 2021 15th Report on Carcinogens, the new entries added bring the total list up to 256 substances, .
The report is prepared by the U.S. National Toxicology Program for the Secretary of the U.S. Department of Health and Human Services. This year’s report coincides with the 50th anniversary of the , signed into law by then-President Richard Nixon.
The report identifies environmental factors, chemicals, infectious agents, physical agents – such as X-rays -- and exposure scenarios but does not include estimates of cancer risk because of the many variables that can affect whether or not a person will develop cancer.
In the latest report, chronic infection with the bacterium known as Helicobacter pylori, or H. pylori, has been listed as known to be a human carcinogen.
H. pylori is a spiral bacteria that can enter the body through food, water or utensils, lives in the digestive tract and is behind most stomach ulcers. It is thought to penetrate the mucous lining of the stomach to establish infection and can lead to stomach cancer. It is more commonly found in countries with less established infrastructures surrounding clean water and sewage systems, but spread from one person to another is possible through saliva or other bodily fluids.
Another new entry to the report is the flame-retardant chemical called antimony trioxide, which in Canada is used for household items such as mattress covers, furniture and carpets.
It is also used in the manufacturing of the plastic material polyethylene terephthalate, or PET. Antimony trioxide is both manufactured and imported into Canada, .
Health Canada states that Canadians are “expected to be exposed to low levels of antimony trioxide from environmental media (soil, drinking water, ambient air) from food and from contact with household items.â€
The agency says it conducted a screening assessment and “concluded that antimony trioxide is not harmful to the health of the general population at current levels of exposure.â€
The final entries into the latest report include six haloacetic acids (HAAs), found as water disinfection byproducts, that are listed as reasonably anticipated to be a human carcinogen.
They are:
- Bromochloroacetic acid (BCA)
- Bromodichloroacetic acid (BDCA)
- Chlorodibromoacetic acid (CDBA)
- Dibromoacetic acid (DBA)
- Dichloroacetic acid (DCA)
- Tribromoacetic acid (TBA)
The HAAs are formed during the water treatment process, when chlorine-based disinfection agents react with organic matter in the source water.
that the maximum acceptable concentration for total HAAs in drinking water is 0.08 milligrams per litre, based on a locational running annual average of a minimum of quarterly samples taken in distribution systems.
“Cancer affects almost everyone’s life, either directly or indirectly,†said Rick Woychik, Director of the U.S. National Institute of Environmental Health Sciences and NTP, in the release. “As the identification of carcinogens is a key step in cancer prevention, publication of the report represents an important government activity towards improving public health.â€