In recent years, PFAS, known as "forever chemicals," have gained worldwide attention due to concerns about their environmental and health impacts. In Japan, the public broadcaster NHK has begun covering this issue, but for the general public, understanding technical explanations and subtle nuances may not be easy. This article explains what PFAS are, why they are considered problematic, and the specific situation in Japan.
PFAS (Per- and Polyfluoroalkyl Substances) is a collective term for organofluorine compounds that contain carbon-fluorine bonds. Chemically speaking, they have a structure where hydrogen atoms in alkyl groups (molecular chains consisting of carbon and hydrogen) are replaced by fluorine atoms.
This definition may seem simple, but in practice, slightly different definitions are used by various research institutions and regulatory authorities, and the number of compounds classified as PFAS is said to range from thousands to tens of thousands. Therefore, in everyday conversation, it is practical to understand PFAS as "a group of artificial compounds with carbon-fluorine bonds."
There are several reasons why PFAS are particularly concerning compared to other chemical substances:
The most notable characteristic of PFAS is their remarkable resistance to degradation. The carbon-fluorine bond is considered one of the strongest chemical bonds in nature, and this bond strength makes PFAS extremely stable in the environment. As a result, once released into the environment, they are very difficult to break down through natural degradation processes and may persist for hundreds, or in some cases thousands of years, depending on environmental conditions.
While the element fluorine itself exists in nature, PFAS with carbon-fluorine bonds do not exist naturally and are completely artificial substances. This means that all PFAS present in our environment have been created and released through human activities. Natural cycle systems are not adapted to process such substances, so once released into the environment, they continue to circulate for long periods.
Many PFAS compounds are water-soluble, which increases their mobility in the environment. They can spread over wide areas through water systems and potentially contaminate drinking water sources. Additionally, some PFAS have properties that allow them to accumulate in living organisms (bioaccumulation), raising concerns about their concentration through the food chain.
The PFAS issue needs to be considered from two major aspects: environmental and health.
The environmental aspect of PFAS is a clear problem recognized by virtually all scientists. The fact that artificially synthesized chemicals remain in the environment for generations without degrading raises serious environmental ethics issues. The long-term impact on ecosystems of non-natural substances continuously accumulating is not yet fully understood.
Of particular concern is that PFAS are now being detected in places far from production sites, such as polar regions and deep seas. This suggests that the entire global ecosystem is already under the influence of PFAS.
Concerns about health aspects are more complex. For widely studied PFAS like PFOA and PFOS, several health effects have been scientifically suggested:
However, research is still ongoing regarding the extent of these health effects at different concentrations, the effects of long-term low-concentration exposure, and many aspects have not yet reached definitive conclusions. Additionally, while there are thousands of PFAS substances, detailed health impact studies are limited to only a few substances.
In Japan, the PFAS issue focuses mainly on the following two types:
In addition to these, PFHxS (Perfluorohexane Sulfonic Acid) has recently been added to the list of regulated substances.
Regulation of PFAS in Japan has progressed in stages:
While these regulations essentially mean prohibition of manufacturing, import, and use, exceptions are allowed for certain applications where alternatives are difficult to find. Additionally, it has been pointed out that environmental standards and drinking water standards are less stringent compared to countries like the United States.
There are characteristic patterns in the sources of PFAS in Japan:
In recent years, there have been reports of PFAS (especially PFOA and PFOS) being detected in rivers, groundwater, and tap water across Japan. Research institutions such as the National Institute for Environmental Studies have advanced their investigations, including attempts to create nationwide contamination maps, but it cannot be said that sufficient nationwide surveys have been conducted yet.
Japanese media coverage of PFAS issues shows several characteristic patterns:
These reporting tendencies may emphasize only certain aspects of the problem, potentially hindering comprehensive understanding.
There are broadly two approaches to PFAS regulation globally:
This difference in regulatory philosophy is behind the perception that Japan's regulations lag behind global trends.
In Europe, there is a movement to regulate "the entire group of PFAS substances," and in the United States, the Environmental Protection Agency (EPA) has indicated a policy to strengthen PFAS regulations in drinking water. At the same time, there is also a direction to balance practicality and safety by setting exceptions for special applications (such as medical devices and special industrial applications).
To address PFAS issues appropriately in Japan, the following challenges need to be tackled:
It is important to conduct nationwide PFAS contamination surveys and disclose the results transparently. Currently, many surveys are limited to specific regions or specific substances, making it difficult to see the overall picture.
It is important to clearly distinguish what is known and unknown from current scientific knowledge and communicate this to citizens. Careful risk communication is required that conveys uncertainties openly while not causing excessive anxiety.
Rather than waiting for complete scientific proof, it may be necessary to take preventive measures when there is a possibility of serious adverse effects. There is room to consider more active regulation, especially for applications where alternative substances are available.
Supporting the development of safe alternative substances and technologies to replace PFAS is also an important challenge. There is potential for Japan to lead the world in developing alternative technologies with lower environmental impact by leveraging its technological capabilities.
The PFAS issue is a global environmental problem that cannot be solved by one country alone. More active international cooperation is required in terms of harmonization of international regulations, information sharing, and joint research.
The PFAS issue raises difficult challenges in our coexistence with chemical substances. How to evaluate and address long-term impacts on the environment and health while pursuing convenience and functionality—the answer is not simple.
However, it is important to face this issue sincerely, accumulate scientific knowledge, and seek balanced responses that incorporate preventive perspectives. While taking into account Japan's specific situation, it is necessary to address problem-solving from a global perspective.
The PFAS issue can be considered an important touchstone for how our society will deal with chemical substances in the future.