Although traditional scented candles can create an atmosphere and soothe emotions, their production, use and disposal processes may have negative impacts on the environment. The following are the main environmental issues and the scientific basis for them: 
1. Material contamination: paraffin and synthetic additives 
(1) The petroleum dependence of paraffin wax 
Source: Most cheap scented candles use paraffin wax, which is a by-product of petroleum refining and is a non-renewable resource. 
Emission from combustion: 
When paraffin is incompletely burned, it may release volatile organic compounds (VOCs) such as benzene, toluene, and formaldehyde. Prolonged inhalation of these substances may pose a threat to respiratory health (the US Environmental Protection Agency (EPA) has classified them as potential carcinogens). 
Exhaust black smoke (carbon particles), polluting the indoor air. 
(2) Synthetic fragrances and dyes 
Artificial flavorings: 
Many brands use "fragrance oil" instead of natural essential oils, and these oils may contain phthalates (a type of plasticizer), which can interfere with the endocrine system. 
The EU has restricted the use of certain phthalates in cosmetics, but the regulation for the candle industry is relatively lenient. 
Chemical dyes: 
The added pigments may contain heavy metals (such as lead and cadmium), which are released into the air during combustion or remain in the wax residue. 
2. Packaging waste: Excessive consumption and recycling challenges 
Non-degradable packaging 
Many scented candles are packaged in multiple layers: plastic film + cardboard box + metal lid, which increases the pressure on waste disposal. 
Low recovery rate of glass jars: 
Although glass can be recycled, containers with remaining wax or label glue need to be thoroughly cleaned; otherwise, they will be discarded. 
Some brands use colored glass (such as dark bottles), which makes recycling more difficult. 
(2) "Fast Fashion" Candle Culture 
Seasonal limited-edition candles and trendy collaboration models have prompted consumers to frequently change their candles, thereby exacerbating resource waste. 
3. Carbon footprint of production and transportation 
Globalized supply chain: 
Raw materials (such as paraffin and flavoring agents) may be transported from oil-producing regions to manufacturing countries, and then redistributed globally, resulting in significant carbon emissions. 
Energy-intensive production: 
The processes of paraffin purification and synthetic fragrance manufacturing rely on fossil fuels. 
4. Inefficiency and pollution during the usage process 
Incomplete combustion: 
If the wick is too long or the ventilation is poor, the candle will produce black smoke, waste the wax and pollute the air. 
Wax residue issue: 
Traditional candles tend to form "memory circles" (with only the center burning), resulting in the waste of the wax at the edges. 
5. Risk of bioaccumulative pollution 
The microplastic particles and synthetic fragrance components from paraffin candles may enter the natural environment through wastewater, affecting aquatic organisms. 
Summary: The environmental shortcomings of traditional scented candles 
Problem Type  Specific Impact 
Material contamination: Paraffin releases VOCs, synthetic fragrances contain plasticizers. 
Packaging waste: Non-biodegradable plastics, low-recycling rate glass jars 
High carbon footprint, reliance on oil, long-distance transportation 
Inefficient use: incomplete combustion, waste of wax residue 
How to reduce the impact? 
Choose natural materials: soy wax, beeswax or coconut wax candles. 
Prioritize simple packaging: plastic-free, refillable design. 
Support local brands: Reduce carbon emissions from transportation. 
Rational consumption: Avoid buying limited edition items just because of the trend.