Formaldehyde (methanal), with the chemical formula CH2O, is a reactive gas. According to information from the Environmental Protection Agency (EPA), "Formaldehyde has been confirmed as a human carcinogen in toxicology studies and can irritate the skin, respiratory tract, and central nervous system."

Most wooden furniture is made from various processed wood materials, and the adhesives used during the manufacturing process contain formaldehyde. During construction, formaldehyde gas is released, and even after completion, the adhesives gradually emit excess formaldehyde. Therefore, formaldehyde is one of the pollutants that contribute to indoor air pollution. 

Formaldehyde has been confirmed by the World Health Organization (WHO) as a carcinogenic and teratogenic substance, posing the following health risks to humans:

1. Irritation:
   Inhalation or contact with high concentrations can cause severe respiratory irritation, edema, skin irritation, eye irritation, and headaches.

2. Allergic Reactions:
   It can lead to allergic dermatitis, dark spots, necrosis, bronchial asthma, and even liver damage, pneumonia, and kidney damage.

3. Mutagenicity:
   High concentrations of formaldehyde have genotoxic properties, potentially leading to nasopharyngeal tumors, colon cancer, brain tumors, and nuclear gene mutations.

4. Other Adverse Effects:
   Symptoms include headaches, dizziness, fatigue, nausea, vomiting, chest tightness, eye pain, sore throat, poor appetite, heart palpitations, insomnia, weight loss, memory impairment, and nervous system disorders. Prolonged exposure in pregnant women may result in fetal deformities or even death, while long-term inhalation in men can lead to sperm abnormalities and reduced sperm count.

1.Avoid Excessive Renovation:
Minimize renovations and reduce the use of wood to prevent formaldehyde exposure.

2.Choose Quality Products Within Your Budget:
Opt for low-formaldehyde wood products, as better quality materials can help reduce formaldehyde levels.

3.Limit the Use of Air Fresheners:
Air fresheners are synthetic chemicals, which may contain traces of formaldehyde.

4.Delay Moving Into Renovated Homes:
Ensure proper ventilation and allow time for formaldehyde levels to drop before moving in.

5.Ventilation Method:
Improving air circulation between indoor and outdoor spaces can lower formaldehyde levels, reducing its harmful effects.

6.Plant Purification Method:
Plants can mildly purify air in lightly polluted spaces, but their effectiveness is limited.

7.Activated Charcoal Adsorption Method:
Bamboo charcoal adsorbs formaldehyde, but once it becomes saturated, formaldehyde can be released again. Rejuvenate charcoal by placing it in the sun for a few days before reuse.

8.Use of Air Purifiers:
Many air purifiers on the market claim to remove formaldehyde. It's recommended to purchase from reputable brands for better assurance.

9.Hire a Professional Formaldehyde Removal Service:
Formaldehyde release increases at 19°C and rises exponentially at 30°C, especially in closed environments with air conditioning. For faster results, hiring a formaldehyde removal company is effective.

Common methods include the use of chitosan, photocatalyst sprays, formaldehyde-removing sprays, and ozone treatments.