Summary of Key Points
This article highlights a fact that is often overlooked: the common chirping of cicadas in summer is not just a harmless background noise; their sounds can be so loud as to damage hearing. Prolonged or even brief exposure to high-intensity cicada noises can lead to high-frequency hearing loss, which in severe cases, may be irreversible. The article also explains the physiological mechanisms behind how cicada noises harm hearing, the reasons why they are louder this year, and what ordinary people can do to protect themselves.
Detailed Analysis
1. How Loud Are Cicadas Really? An Invisible Killer Comparable to a Chainsaw
You might think that cicada noises are just annoying, but their volume is much greater than you realize:
- The sound of a single cicada is about 70 decibels (similar to normal conversation), while a group of cicadas can produce sounds over 85 decibels (equivalent to the noise on a busy street);
- During the massive outbreak of the “17-year cicadas” in North America, the sound near a tree was nearly 100 decibels (comparable to the noise from a hair dryer or a motorcycle);
- In Africa, there is a particular species of cicada that produces sounds as high as 106.7 decibels at half a meter away, almost as loud as a chainsaw!
The duration of exposure is also crucial: According to American occupational safety standards, you can be exposed to 85 decibels for a maximum of 8 hours per day; for every additional 3 decibels, the safe exposure time is halved (for example, 88 decibels allow only 4 hours of exposure, and 91 decibels only 2 hours). The student Yang in the news suffered hearing damage after camping for 4 hours because he stayed in an area with a high concentration of cicadas.
2. Why Do Cicada Noises Harm Hearing? The Hair Cells in Our Ears Are Damaged
Our ears contain an organ called the cochlea, which contains many hair cells that convert sound waves into nerve signals sent to the brain. These hair cells are irrenewable; once they die, they cannot be replaced:
- Short-term, high-intensity exposure (such as camping for a few hours) can cause the hair cells to swell, leading to symptoms like a feeling of fullness in the ear, tinnitus, and difficulty hearing high-pitched sounds (like phone notifications or bird songs). With timely medical attention, some recovery is possible;
- Long-term, repeated exposure (such as garden workers working in cicada-infested areas year after year) can result in permanent damage to the hair cells and a decline in hearing;
- There is also a phenomenon called “hidden hearing loss,” where even if a hearing test shows no apparent damage, the connections between the hair cells and nerves may have been damaged, making it difficult to hear complex sounds in noisy environments (such as conversations in a crowded restaurant).
Additionally, cicada noises are concentrated in the frequency range of 3000–8000 hertz, which is the most sensitive part of our hearing range. This is why high-frequency hearing is affected first.
3. Why Are Cicadas Louder This Year? High Temperatures and Climate Change Are Contributing
Have you noticed that cicadas are louder or more frequent this summer? The main reason is high temperatures:
- Male cicadas produce sounds using a “drum-like” organ in their abdomens, and the muscles of this organ are very sensitive to temperature; higher temperatures cause the muscles to contract faster and more forcefully, resulting in louder and more frequent noises;
- Climate change has also extended the duration of cicada activity: In Japan, the first day of cicada chirping has been observed to be earlier each year, and in the United States, it is predicted that certain species will emerge earlier. This means that cicadas may be active from morning until late at night this summer.
However, some studies suggest that some cicadas adjust their body temperature by basking in the sun, so not all cicadas are affected by temperature changes, but the overall trend is an increase in the duration of their activity.
4. Who Is at Highest Risk? These Groups Need to Be Extra Careful
Not everyone is at risk of hearing damage from cicada noises, but the following groups are particularly vulnerable:
- Outdoor workers, such as gardeners and forestry workers, who are exposed to cicadas year-round and are more likely to suffer permanent damage (as seen with the 60-year-old gardener in the news);
- Campers and outdoor enthusiasts who spend long periods in forests with dense populations of cicadas;
- Residents living in areas with many cicadas: Exposure over time can gradually lead to hearing damage (as seen with the resident in Hangzhou).
These groups need to take extra precautions to protect their hearing.
5. How to Protect Yourself from Cicada Noises
Protection is simple and mainly involves avoiding, preventing, and checking for signs of damage:
- Avoid: Stay away from dense forests between 10 a.m. and 4 p.m., when cicadas are most active;
- Prevent: Wear noise-canceling earplugs (ordinary sponge earplugs will work);
- Check: If you experience symptoms such as a feeling of fullness in the ear, tinnitus, or difficulty hearing high-pitched sounds, immediately leave the noisy environment. If these symptoms persist for more than a day, go to the hospital for a hearing test—intervention is crucial before the hair cells are permanently damaged.
Final Reminder
Cicada noises are not something to ignore; they can be quite harmful. Especially for those at high risk, it’s essential to take proper precautions, as once hearing is damaged, it cannot be restored.