TAMPA DRINKING WATER

Tampa drinking water is a blend of surface water, groundwater, and desalinated seawater supplied by Tampa Bay Water. The water is treated and meets all federal standards set by the Environmental Protection Agency (EPA), but due to regional sources and infrastructure, some residents report issues with taste and may choose to use a home filtration system.

Photography By Clément Bardot – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=45465505

Sources of Tampa Drinking water

Tampa Bay Water, the utility that serves the Tampa Bay area, uses a diversified approach to ensure a reliable Tampa drinking water supply.

Surface water: This includes water from the Hillsborough River and the Tampa Bypass Canal.
Groundwater: Water is drawn from wells in the Floridan Aquifer, the primary source of groundwater in Florida.
Desalinated seawater: The Tampa Bay Seawater Desalination facility provides a drought-proof source of drinking water for the region.

Safety and quality

Tampa drinking water is considered safe to drink according to EPA and state regulations, but its quality has been assessed differently by other organizations, and consumer reports vary.

Safety standards: Public water supplies are regularly tested and regulated by the EPA and Florida Department of Environmental Protection (FDEP).
Disinfection: Chlorine is used as a disinfectant to kill harmful microorganisms. To minimize disinfection by-products, Tampa Bay Water uses a combination of chlorination and monochloramines.
Consumer concerns: Some water quality watchdogs, such as the Environmental Working Group (EWG), argue that some contaminants, though at legally acceptable levels, may still pose long-term health risks. In 2023, an analysis by SpringWell Water noted that while Tampa’s water met EPA standards, six contaminants exceeded EWG health guidelines, including total trihalomethanes, chromium-6, arsenic, and radium.
Taste and odor: Tampa’s water can sometimes have a distinctive taste or odor due to the natural mineral content from its source waters, chlorine used in the treatment process, and other factors like algae. The high mineral content can also lead to hard water buildup.

If you have concerns about the quality of your Tampa drinking water, options are available:

Home filtration: Many residents use water filters to improve the taste and remove impurities.
Local reports: Stay informed about the water quality in your specific area by checking your local utility or the FDEP if you have any concerns.
Water testing: If you use a private well, you are responsible for testing your water, as private wells are not regulated by the EPA.

What contaminants were found in Tampa’s water above EWG recommendations?

According to the Environmental Working Group (EWG) database, several contaminants were found in Tampa’s water that exceeded EWG health guidelines between 2021 and 2023. It is important to note that all detected levels met federal legal standards and that the EWG’s health guidelines are often stricter than EPA regulations.

Some of the key contaminants that exceeded EWG’s recommendations include:

Arsenic: In 2021, tap water tested from the City of Tampa had arsenic levels 198 times higher than the EWG’s Health Guideline, though still within federal limits.
Radium, combined (-226 and -228): This radioactive element was found at up to 19 times above EWG’s Health Guideline.
Total trihalomethanes (TTHMs): This group of cancer-causing contaminants, which includes chemicals like chloroform and bromoform, was detected at up to 217 times above EWG’s Health Guideline.
Haloacetic acids (HAA5): Another byproduct of water disinfection, this group of chemicals was found at levels up to 126 times above EWG’s recommended limit.
Chromium (hexavalent): Also known as chromium-6, this industrial pollutant was found at levels 3.8 times higher than the EWG’s Health Guideline.
Nitrate: This chemical, often from agricultural and urban runoff, was detected at 6.6 times above the EWG’s Health Guideline.
Bromodichloromethane and dibromochloromethane: These are individual trihalomethane components, and both were found at elevated levels compared to EWG guidelines.

While these contaminants were detected, EWG and other organizations advocate for stronger standards and improved infrastructure to minimize potential long-term health risks.

What are the health risks of long-term exposure to these contaminants?

Long-term exposure to contaminants like arsenic, radium, trihalomethanes, haloacetic acids, hexavalent chromium, and nitrates, even at levels that meet legal standards, can be associated with an increased risk of cancer and other adverse health effects. Different contaminants pose varying levels of risk and affect different organs.

Carcinogenic effects

Several of the contaminants found in Tampa drinking water are classified as possible or probable human carcinogens by regulatory and health organizations.

Arsenic: Classified as a known human carcinogen, chronic exposure increases the risk of skin, lung, and bladder cancer.
Total trihalomethanes (TTHMs): Chronic exposure to elevated levels has been associated with an increased risk of bladder, colon, and rectal cancer. This includes specific TTHMs like bromodichloromethane (BDCM), which is classified as likely to be carcinogenic to humans based on animal studies.
Haloacetic acids (HAA5): Some HAA5 compounds, including dichloroacetic and trichloroacetic acid, are classified as possible human carcinogens and have been linked to an increased risk of bladder cancer.
Radium: This radioactive substance is a known human carcinogen. Long-term exposure, particularly at high levels, is associated with an increased incidence of bone, liver, and breast cancer.
Hexavalent chromium (Chromium-6): Ingestion of chromium-6 has been shown to increase the risk of stomach and intestinal tumors in animal studies. In humans, it is linked to stomach cancer and reproductive harm.

Non-carcinogenic health risks

In addition to cancer risks, these contaminants can cause a range of other serious health issues, especially with long-term exposure.

Arsenic: Can cause developmental effects, cardiovascular disease, and liver and kidney damage. It can also lead to skin lesions, nerve damage, and diabetes.
TTHMs and HAA5: Besides cancer, these disinfection byproducts can cause liver, kidney, and central nervous system problems. Some studies also suggest potential reproductive and developmental issues, though findings are not definitive.
Radium: At high doses, radium can cause anemia, cataracts, fractured teeth, and reduced bone growth.
Hexavalent chromium (Chromium-6): High-level exposure can cause damage to the liver and kidneys. Studies also indicate reproductive harm.
Nitrate: High levels of nitrate can cause methemoglobinemia (blue baby syndrome) in infants, a potentially fatal condition that affects the blood’s ability to carry oxygen. Long-term exposure in adults has been linked to potential thyroid problems and increased risks of certain cancers.
Dibromochloromethane (DBCM): A type of TTHM, DBCM is associated with liver and kidney injury in lab animals at high exposure levels.

Factors influencing health risks

The actual health risks depend on a number of factors, including the concentration of the contaminant, the duration of exposure, and individual susceptibility. Vulnerable populations, such as infants, children, pregnant women, and the elderly, may face a higher risk from exposure.

Many government and health agencies, including the Centers for Disease Control and Prevention (CDC), stress that EPA-regulated water is safe to drink. However, organizations like the EWG highlight that legal standards are not always sufficient to protect against all potential health effects, especially with long-term exposure to low levels of contaminants.

What are the potential health risks for pregnant women and infants?

Several contaminants found in Tampa’s water, even at levels meeting federal standards, pose increased risks to pregnant women and infants. These groups are especially vulnerable because a fetus or infant’s developing body is more sensitive to certain chemicals and can have a harder time processing them.

Risks during pregnancy

Arsenic: Exposure to even low levels of arsenic in drinking water during pregnancy is linked to adverse birth outcomes. Studies have associated it with an increased risk of low birth weight and babies being smaller than expected for their gestational age. Animal studies have also shown potential links to birth defects and miscarriages.
Disinfection Byproducts (DBPs): This includes trihalomethanes (TTHMs) and haloacetic acids (HAA5). Some studies have found associations between DBP exposure and adverse pregnancy outcomes like low birth weight, intrauterine growth retardation, and spontaneous abortion. Higher exposure to certain DBPs, like brominated trihalomethanes, has also been linked to birth defects, including heart, musculoskeletal, and neural tube defects.
Hexavalent Chromium (Chromium-6): This chemical is considered a likely cause of developmental toxicity in humans. Exposure during pregnancy may affect fetal development and has been linked to reproductive issues in women, including pregnancy loss and spontaneous abortion.
Nitrate: While the connection is not definitive, some research has suggested that high nitrate levels could be associated with an increased risk of birth defects or miscarriage. A 2021 Stanford study of 1.4 million California births found that pregnant women exposed to higher levels of nitrate were at a higher risk of spontaneous preterm birth.
Radium: Exposure to this radioactive substance in drinking water has been linked to an increased risk of birth defects.

Risks for infants

Nitrate (“Blue Baby Syndrome”): The most well-documented risk for infants is methemoglobinemia, or “blue baby syndrome,” caused by high levels of nitrate. Ingesting formula mixed with high-nitrate water can inhibit an infant’s blood from carrying oxygen, which can be fatal. Infants are particularly susceptible because they convert more nitrate into nitrite and have a harder time converting methemoglobin back into hemoglobin.
Arsenic: In addition to its impact during pregnancy, arsenic exposure can negatively affect infant growth after birth. Studies have found associations between higher maternal arsenic levels and slower physical growth in male infants during their first year.
Lead: While not listed in the initial EWG report for Tampa, lead can enter drinking water through aging plumbing. The EPA and CDC state there is no safe level of lead for children. Exposure to even low levels can cause learning and behavioral problems, lower IQ, slowed growth, and anemia.
Chemical Sensitivities: Because of their smaller body size, infants and children consume more water for their size than adults, which increases their overall exposure to any contaminants.

How to reduce risk

Use an alternative water source: The Washington State Department of Health recommends using bottled water to prepare infant formula if your water has nitrate levels above 10 mg/L.
Filter your water: Using a certified water filter, such as a reverse osmosis system, can significantly reduce or remove many of these contaminants. Filters can also remove fluoride, which some studies have linked to adverse neurological effects in infants at elevated levels.
Test your water: If you have a private well, test it annually for nitrates and other contaminants.

Levels of arsenic, DBPs, chromium-6, and nitrate found in Tampa’s water.

Based on Environmental Working Group (EWG) data from 2021 to 2023, the following levels of key contaminants were found in the City of Tampa’s water, though it is important to remember that these levels met federal legal standards.

Arsenic

Maximum detected level: 0.100 parts per billion (ppb).
EWG Health Guideline: 0.004 ppb.
The detected level was 25 times higher than the EWG’s health-based guideline.

Disinfection Byproducts (DBPs)

Total Trihalomethanes (TTHMs)

Average level: 14.5 ppb.
Legal limit: 80 ppb.
EWG Health Guideline: 0.15 ppb.
This average level was 97 times higher than the EWG’s guideline.

Haloacetic Acids (HAA5)

Average level: 14.5 ppb.
Legal limit: 60 ppb.
EWG Health Guideline: 0.1 ppb.
This average level was 145 times higher than the EWG’s guideline.

Hexavalent Chromium (Chromium-6)

Average level: 0.0769 ppb.
Legal limit: None, but the EPA sets a legal standard for total chromium, which is 100 ppb.
EWG Health Guideline: 0.02 ppb.
The detected level was 3.8 times higher than the EWG’s public health goal.

Nitrate

Average level: 0.347 parts per million (ppm).
Legal limit: 10 ppm.
EWG Health Guideline: 0.14 ppm.
This average level was 2.5 times higher than the EWG’s health guideline.

Additional Websites Created by Joe Angrisano: