Chemical incense harms human health and the environment in the following ways:

1. **Health Risks**:

   - **Toxic Emissions**: Chemical incense releases harmful pollutants like volatile organic compounds (VOCs), benzene, and formaldehyde, which can irritate the respiratory system and cause headaches, dizziness, or nausea.

   - **Respiratory Issues**: Prolonged exposure to smoke from synthetic incense can lead to chronic respiratory problems, asthma, or worsen allergies.

   - **Carcinogens**: Burning chemical incense may release carcinogens like polycyclic aromatic hydrocarbons (PAHs), increasing the risk of cancer over time.

2. **Environmental Harm**:

   - **Air Pollution**: Chemical incense contributes to indoor air pollution by releasing harmful particles and gases into the environment.

   - **Non-biodegradable Ingredients**: Many synthetic incense sticks contain plastics, artificial binders, and toxic dyes that don't break down naturally, causing environmental harm during production and disposal.