top of page
  • Writer's pictureEnvironmental Health Project

Blue Hydrogen: A Threat to Public Health?

A number of legislators and industry representatives have recently touted “blue hydrogen” as a clean solution to many of the world’s energy challenges. Generally speaking, hydrogen is a clean fuel that, when used in a fuel cell, produces no pollution. The blue hydrogen process, however, is not the panacea some would make it out to be. And while energy experts have raised real questions about blue hydrogen’s environmental footprint and business model, there can be no doubt about one unwanted consequence: If blue hydrogen production ramps up, there will be an associated increase in the risks to public health.

A hydrogen plant in the Netherlands.

What is blue hydrogen? To talk about blue hydrogen, we first need to talk about green hydrogen. (Different colors are assigned to represent the various hydrogen-producing processes.) Green hydrogen is created through a process of extracting hydrogen from water molecules, which can then be used as a light and highly reactive fuel, typically in hydrogen fuel cells (HFCs)—which operate like batteries— to be used in cars, laptops, or backup power system, or even in power plants. This technology is called “green” because it uses renewable sources of energy to extract the hydrogen and because the only byproduct of producing and using it is oxygen and water, making it very eco-friendly. No harmful emissions are produced and there are no costs associated with handling and storing toxic materials like diesel fuel or battery acid.

Homes with rooftop solar panels next to a solar array on the ground and a tank labeled H2 with sleek equipment nearby labeled "Hydrogen H2."
Green hydrogen produced using solar energy might look like this.

Green hydrogen would provide a cleaner form of energy in many uses currently associated with pollution and would slow climate change, but experts say that the technology for economically producing it is still some years away. Eventually, though, as technology improves, green hydrogen may serve as an environmentally sound fuel for many years to come. Blue hydrogen, by contrast, is produced through a complex and energy-intensive process that mixes methane gas with water to create carbon dioxide and hydrogen. Unlike its cheaper and dirtier cousin, gray hydrogen (which also uses methane gas but emits the carbon dioxide byproduct directly into the air as pollution), blue hydrogen captures some of the carbon dioxide emissions and stores them underground. This underground storage process is called “carbon capture and storage” or “carbon capture and sequestration” (CCS). It’s what earns the process its “blue” name. Can blue hydrogen save the planet? Blue hydrogen may not be the ready-for-prime-time fuel some have touted it to be. First, it’s relatively expensive to produce. A lot of energy must be expended to extract the methane fuel stock then to isolate, process, and stockpile usable hydrogen. A lot more energy is spent to capture the CO2 and store it underground. So much energy must be used in the process that some researchers say that the carbon footprint to create and burn blue hydrogen is significantly greater than using either oil or gas directly to heat your home or business.[1] Further, CCS technology is a problematic solution to taking the carbon out of, or “decarbonizing,” emissions. According to a current article in Scientific American:

[C]arbon dioxide doesn’t necessarily stay in the rocks and soil. It may migrate along cracks, faults and fissures before finding its way back to the atmosphere. Keeping pumped carbon in the ground—in other words, achieving net negative emissions—is much harder. Globally there are only [a] handful of places where this is done. None of them is commercially viable…. Meanwhile numerous CCS plants have failed. In 2016 the Massachusetts Institute of Technology closed its Carbon Capture and Sequestration Technologies program because the 43 projects it was involved with had all been canceled, put on hold or converted to other things.[2]

Many experts believe that some end uses—long-haul heavy-duty trucking, high-temperature industrial processes like steelmaking, and long-duration energy storage of renewable energy—may not be readily electrified or decarbonized through other less polluting technology. So, blue hydrogen may offer a way to temporarily decarbonize such uses. But experts also recommend that the technology should be deployed only when it serves the most efficient pathway to a decarbonized economy, complementing proven and readily available alternatives.

There is also speculation that shale gas corporations are pushing blue hydrogen as a way to ensure a market for gas investments still in the ground. To protect against losing these investments, and to make the blue hydrogen industry attractive from a business perspective, sizeable subsidies of public dollars will no doubt be required. The argument can be made that these tax dollars would be better spent on lower-emission and no-emission renewable technologies.

Is blue hydrogen good for public health?

Setting aside serious technology and business uncertainties, the production of blue hydrogen raises the risk of public health impacts and the related healthcare costs in several critical ways.

First, blue hydrogen production requires the extraction of fossil fuels—typically shale gas—as feeder stock, demanding many more hydraulically fractured shale gas wells in areas already overburdened by this heavy industry. Increased well production means greater emissions of a variety of toxic chemicals, such as fine particulate matter (PM2.5), volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs), glycol, and radium into local communities. Studies have found that these emissions may raise the risk of asthma and other respiratory illnesses, heart disease and heart attacks, birth defects and pre-term deliveries, mental health issues, and cancer.

Shale gas drill rig and open air impoundment

Additionally, the production of blue hydrogen itself raises the same elevated health risks for people living in proximity to these large-scale industrial complexes. With larger facilities comes greater emissions and greater risks of spills, leaks, or other contamination events. Given the right atmospheric conditions, pollution can travel for miles, impacting residents far from the source of emissions.

How else will public health be impacted by blue hydrogen?

Public health may also be impacted by the transportation and storage of gas feeder stock, used wastewater, gas byproducts, and the hydrogen itself once produced. Whether these products or byproducts are transported by diesel trucks, trains, ships, or pipelines, potentially harmful pollution releases occur at every stage of the process. The risks of accidents and explosions increase, too. Operators are also challenged to find proper ways to store or dispose of other waste, which typically contains hazardous chemicals and often radioactive substances.

While blue hydrogen might be considered cleaner than some other available fuel options (think coal and oil), it’s not without a carbon footprint. Utilities want to take hydrogen and combust it the way you would current fuels, an alternative to the fuel cell technology described above. As hydrogen production ramps up, utilities have discussed mixing hydrogen with methane gas to burn as fuel, emitting greenhouse gases in the process. Even if the hydrogen is derived using green technologies, burning it with methane can produce dangerously high levels of nitrogen oxides (NOx). Two studies found that burning hydrogen-enriched methane gas can lead to NOx emissions up to six times that of burning methane alone.[3] NOx plays a major role in the formation of smog—a major contributor to asthma and other respiratory issues.

Further, a large-scale blue hydrogen industry would facilitate more releases of climate-altering methane, which carries a heavy public health burden, as lethal storms, fires, heat waves, floods, and other extreme weather events impact people’s physical and mental health worldwide.

How can we protect public health from blue hydrogen production?

Whether it’s blue hydrogen or fossil fuel production, the Environmental Health Project (EHP) calls for robust and comprehensive public health protections:

  • Industry must be compelled to effect stringent emissions detection and reporting—working with communities to reduce exposure and alert the public of any unusual releases, whether planned or accidental.

  • Government agencies must be intrinsically involved in making sure industry complies with pollution standards, holding operators accountable when they do not comply.

  • Health impact assessments and other community health monitoring must be put in place to ensure public health is protected today and into the future. Residents must be informed fully about health risks to which they are exposed.

  • It is not enough to regulate sources of emissions singly. All sources of emissions must be aggregated to determine actual levels of pollution the public is exposed to in any given locality.

  • Production facilities, well pads, compressor stations, and other shale gas infrastructure must be situated far enough from areas of human activity—including homes, schools, businesses, and recreational facilities—to protect public health. EHP recommends these setback distances be at least one-half mile.

  • Communities must be given a say as to whether this development happens within their borders, and there must be clear channels of communication between governmental agencies, industrial operators, and community leaders.

When public health becomes part of the blue hydrogen conversation, only then can we truly begin to limit the serious risk to human health this industry poses.


[1] Howarth, R.W., Jacobson, M.Z. (August 12, 2021). How green is blue hydrogen? Energy Science & Engineering. 9: 1676–1687. [2] Oreskes, N. (August 1, 2022). Carbon-Reduction Plans Rely on Tech That Doesn't Exist, Scientific American 327, 2, 90. [3] Milford, L., Mullendore, S., Ramanan, A. (December 14, 2020). Hydrogen Hype in the Air (blog). Clean Energy Group.


bottom of page