Elevated Bladder Cancer in Northern New England—Drinking Water and Arsenic
A map of bladder cancer mortality rates
Study finds bladder cancer risk was associated with water intake among participants with a history of private domestic well use. The trend was significant for participants who used shallow dug wells exclusively—a well type that typically has low arsenic concentrations but may have had higher concentrations historically.
Bladder cancer rates have been elevated in northern New England (Maine, New Hampshire, and Vermont) for at least 5 decades compared to the rest of the United States. This excess is seen in both males and females, which suggests environmental causal factors. The high proportion of private domestic wells in this region with arsenic led to the hypothesis that drinking water from these wells may play a role in bladder cancer occurrence.
In this collaborative study, scientists from the National Cancer Institute, Geisel School of Medicine at Dartmouth, the Departments of Health for Maine, New Hampshire, and Vermont, and the U.S Geological Survey (USGS) examined the role of private well water consumption and arsenic concentrations on bladder cancer risk. The study used approximately 2,300 participants (cancer patients and control subjects) and collected risk factor information consisting of lifetime water consumption (including water used in food preparation) to calculate total water intake. Lifetime arsenic exposure was calculated as the average annual arsenic concentration; arsenic daily intake was calculated as the average concentration times the number of liters per day of consumption. Cumulative arsenic intake and number of years with arsenic greater than 10 micrograms per liter were also evaluated. Ancestry, smoking, occupation, and use of wood-burning stoves, as well as shellfish and bracken fern consumption, were examined. The assignment of arsenic level was done by direct measurement of concentrations in current (2001-04) and past wells. The inability to sample many past wells required estimation of arsenic levels from models. Ultimately, arsenic level was assigned for more than 85 percent of exposure years for nearly 90 percent of study participants.
Bladder cancer risk increased with increasing water intake; however, bladder cancer risk was significantly associated with water intake among participants with a history of private domestic well use. The trend was significant for participants who used shallow dug wells exclusively, and particularly dug wells used prior to 1960—a well type that typically has low current arsenic concentrations but may have had larger concentrations historically. Cumulative arsenic exposure had twice the risk in the highest compared to the lowest exposure group. Of the factors not related to water intake, only smoking and occupation (well-known risk factors) were related to increased bladder cancer risk, but neither factor appeared to play an important role in the New England bladder cancer excess.
Our findings support an association between low-to-moderate levels of arsenic in drinking water and bladder cancer risk in New England. The findings increase the understanding of a potential source of contamination (from land application of agricultural arsenic-based pesticides) that has not been seen in recent times, perhaps because the hazard has been diminished (such pesticides are no longer in use) or because shallow wells, once dominant in the region, have been largely replaced by deeper wells drilled into fractured crystalline bedrock. Although the increase in risk associated with use of deeper drilled wells was not significant, these newer deep wells have recently been identified as having high arsenic concentrations throughout New England. Study results are expected to increase awareness of the potential for drilled wells to cause exposure to arsenic and the potential link to future adverse health outcomes in New England.
This study was supported by the Intramural Research Program of the National Institutes of Health, National Cancer Institute, Division of Cancer Epidemiology and Genetics (contract N02-CP 01037).
News Releases
Broadcast (Television/Radio)
- PBS NewsHour (included as a brief mention in the daily summary)†
- NBC News Channel 5, WPTZ Private Wells could Lead to Higher Risk of Bladder Cancer, Study Shows †
- ABC9, WMUR9 Study Shows Private Wells could be Linked to Bladder Cancer †
- Maine Public Radio Study: Arsenic in Wells Elevates Cancer Risk†
- New Hampshire Public Radio Study Links Arsenic in Northern New England Wells to Bladder Cancer†
Print/Web
- Nashua Telegraph DES: Test Wells to Prevent Cancer†
- Portland Press Herald Study Links Arsenic in Well Water to Higher Risk of Bladder Cancer in Northern New England†
- Medscape Arsenic-Contaminated Well Water Boosts Bladder Cancer Risk†
- Science Daily Elevated Bladder Cancer Risk in New England, Arsenic in Drinking Water†
- CURE Magazine Arsenic in New England Well Water Suspected Root of 50-Year Bladder Cancer Rise†
- OncologyNurseAdvisor Well Water a Suspected Cause of Bladder Cancer in New England†
- AJMC.com (American Journal of Managed Care) Arsenic in Private Wells Responsible for Surge in Bladder Cancer in New England†
- Fox News Health Arsenic in New England Well Water tied to Bladder Cancer Risk†
- The Express [UK] DRINKING WATER SCARE: Homeowners at Risk from Dangerously High Levels of Deadly Arsenic†
- MedicalResearch.com Study Links Well-Water Arsenic To Increased Bladder Cancer Risk in New England†
Wire Service
- Reuters Arsenic in New England Well Water Tied to Bladder Cancer Risk†
- HealthDay Well Water a Suspected Cause of Bladder Cancer in New England†
- UPI Well water a suspected cause of bladder cancer in New England†
† Hypertext links to non-USGS products and services; and the use of trade names, trademarks, company names, or other references to non-USGS products and services are provided for information only and do not constitute endorsement or warranty by the U.S. Geological Survey (USGS), U.S. Department of the Interior, or U.S. Government.
Study finds bladder cancer risk was associated with water intake among participants with a history of private domestic well use. The trend was significant for participants who used shallow dug wells exclusively—a well type that typically has low arsenic concentrations but may have had higher concentrations historically.
Bladder cancer rates have been elevated in northern New England (Maine, New Hampshire, and Vermont) for at least 5 decades compared to the rest of the United States. This excess is seen in both males and females, which suggests environmental causal factors. The high proportion of private domestic wells in this region with arsenic led to the hypothesis that drinking water from these wells may play a role in bladder cancer occurrence.
In this collaborative study, scientists from the National Cancer Institute, Geisel School of Medicine at Dartmouth, the Departments of Health for Maine, New Hampshire, and Vermont, and the U.S Geological Survey (USGS) examined the role of private well water consumption and arsenic concentrations on bladder cancer risk. The study used approximately 2,300 participants (cancer patients and control subjects) and collected risk factor information consisting of lifetime water consumption (including water used in food preparation) to calculate total water intake. Lifetime arsenic exposure was calculated as the average annual arsenic concentration; arsenic daily intake was calculated as the average concentration times the number of liters per day of consumption. Cumulative arsenic intake and number of years with arsenic greater than 10 micrograms per liter were also evaluated. Ancestry, smoking, occupation, and use of wood-burning stoves, as well as shellfish and bracken fern consumption, were examined. The assignment of arsenic level was done by direct measurement of concentrations in current (2001-04) and past wells. The inability to sample many past wells required estimation of arsenic levels from models. Ultimately, arsenic level was assigned for more than 85 percent of exposure years for nearly 90 percent of study participants.
Bladder cancer risk increased with increasing water intake; however, bladder cancer risk was significantly associated with water intake among participants with a history of private domestic well use. The trend was significant for participants who used shallow dug wells exclusively, and particularly dug wells used prior to 1960—a well type that typically has low current arsenic concentrations but may have had larger concentrations historically. Cumulative arsenic exposure had twice the risk in the highest compared to the lowest exposure group. Of the factors not related to water intake, only smoking and occupation (well-known risk factors) were related to increased bladder cancer risk, but neither factor appeared to play an important role in the New England bladder cancer excess.
Our findings support an association between low-to-moderate levels of arsenic in drinking water and bladder cancer risk in New England. The findings increase the understanding of a potential source of contamination (from land application of agricultural arsenic-based pesticides) that has not been seen in recent times, perhaps because the hazard has been diminished (such pesticides are no longer in use) or because shallow wells, once dominant in the region, have been largely replaced by deeper wells drilled into fractured crystalline bedrock. Although the increase in risk associated with use of deeper drilled wells was not significant, these newer deep wells have recently been identified as having high arsenic concentrations throughout New England. Study results are expected to increase awareness of the potential for drilled wells to cause exposure to arsenic and the potential link to future adverse health outcomes in New England.
This study was supported by the Intramural Research Program of the National Institutes of Health, National Cancer Institute, Division of Cancer Epidemiology and Genetics (contract N02-CP 01037).
News Releases
Broadcast (Television/Radio)
- PBS NewsHour (included as a brief mention in the daily summary)†
- NBC News Channel 5, WPTZ Private Wells could Lead to Higher Risk of Bladder Cancer, Study Shows †
- ABC9, WMUR9 Study Shows Private Wells could be Linked to Bladder Cancer †
- Maine Public Radio Study: Arsenic in Wells Elevates Cancer Risk†
- New Hampshire Public Radio Study Links Arsenic in Northern New England Wells to Bladder Cancer†
Print/Web
- Nashua Telegraph DES: Test Wells to Prevent Cancer†
- Portland Press Herald Study Links Arsenic in Well Water to Higher Risk of Bladder Cancer in Northern New England†
- Medscape Arsenic-Contaminated Well Water Boosts Bladder Cancer Risk†
- Science Daily Elevated Bladder Cancer Risk in New England, Arsenic in Drinking Water†
- CURE Magazine Arsenic in New England Well Water Suspected Root of 50-Year Bladder Cancer Rise†
- OncologyNurseAdvisor Well Water a Suspected Cause of Bladder Cancer in New England†
- AJMC.com (American Journal of Managed Care) Arsenic in Private Wells Responsible for Surge in Bladder Cancer in New England†
- Fox News Health Arsenic in New England Well Water tied to Bladder Cancer Risk†
- The Express [UK] DRINKING WATER SCARE: Homeowners at Risk from Dangerously High Levels of Deadly Arsenic†
- MedicalResearch.com Study Links Well-Water Arsenic To Increased Bladder Cancer Risk in New England†
Wire Service
- Reuters Arsenic in New England Well Water Tied to Bladder Cancer Risk†
- HealthDay Well Water a Suspected Cause of Bladder Cancer in New England†
- UPI Well water a suspected cause of bladder cancer in New England†
† Hypertext links to non-USGS products and services; and the use of trade names, trademarks, company names, or other references to non-USGS products and services are provided for information only and do not constitute endorsement or warranty by the U.S. Geological Survey (USGS), U.S. Department of the Interior, or U.S. Government.