Why are Synthetic Frangrances so Toxic?

Most of us have had the experience of being overwhelmed by a scent that is supposed to be nice, but in high amounts signals to our brains that something is not right. Artificial scents, also known as synthetic fragrances, are complex mixtures of various chemical compounds designed to mimic natural scents. However, unlike their natural counterparts, these compounds often include:

1. Phthalates: Used to prolong the shelf life of fragrances and make them last longer on the skin. Phthalates are esters of phthalic acid, such as Diethyl phthalate (DEP), and di-n-butyl phthalate (DBP).
2. Parabens: Used as preservatives to prevent microbial growth. Parabens are esters of para-hydroxybenzoic acid. They have a high dermal uptake, and known to be estrogenic in vivo. Common Examples: Methylparaben, propylparaben, butylparaben.
3. Synthetic Musks: Used for their long-lasting scent profile. These are polycyclic or nitro musks. Common Examples: Musk ketone, musk xylene. Synthetic musk is very neurotoxic and found in wastewater from cleaners, detergents,and fabric softeners. It causes neuropathologic alterations, demyelination, as well as distal axonal degeneration and nerve damage in specific areas of the CNS.
4. Volatile Organic Compounds (VOCs): These are gases emitted from certain solids or liquids, including many artificial fragrance ingredients. Often in the form of compressed aerosols, volatile organic compounds (VOCs) are increasing to the point they pose a significant negative risk to the atmosphere, environment and human health (5). Common Chemicals: Ethanol, acetone, benzene, toluene. Toluene is associated with cerebellar and brainstem atrophy, and loss of differentiation between the gray and white matter troughout the central nervous system. 

These chemicals are so toxic because they not only are complex, large molecules that the body has no easy way to detoxify, but they also bioaccumulate, leading to allergic reactions to artificial fragrance exposure. If anyone you have know has developed an allergy to artificial scents, they likely had lifelong exposure and may be unable to pass by the laundry detergent or perfume isle in grocery stores without getting a reaction. The reason has to do with the fact that synthetic odors target olfactory receptors that are expressed in various cells and tissues throughout the body, including the lungs, intestines, skin, heart and blood cells (5).

Artificial scents have shown to have endocrine disrupting effects, and a host of symptoms, including neural disturbances (e.g., headache,  reproductive problems, depression, and migraine), breast cancer and polycystic ovary syndrome, skin and airway hypersensitivity, gynecomastia, liver and thyroid toxicity, and teratogenic toxicity effects (6).

As noted in one study:

“The endocrine-immune-neural axis perturbation pathways of these chemicals are being proven. Despite the revelations of cause-effect nexus, a majority of the vulnerable populations are unaware and unmotivated to avoid these ‘slow poisons’…"

"Fragrance compounds share configurational similarity with carcinogenic environmental hydrocarbons and they provoke the expression of cytochrome group monooxygenase enzyme aromatase. This enzyme aromatizes androgens to form estrogen, the powerful signaling hormone, which underlies the majority of morbidities…

Evidences are emerging that the fragrance compounds are endocrine disruptors, capable of upsetting the hormonal signaling systems. The pathologies triggered by them can manifest in any form such as neuropathies (depression, autism), neoplasms (breast cancer, prostate cancer), endocrinopathies (gynacomastia), organ damage (hepatotoxicity), among others" (6).

List of Chemicals in Artificial Fragrances

• hydroxyisohexyl 3-cyclohexene carboxaldehyde,
• sorbitan sesquioleate,
• phenoxyethanol,
• salicylaldehyde,
• glutaraldehyde,
• hydroperoxides,
• trimethylbenzenepropanol,
• dipropylene glycol,
• benzyl benzoate,
• oil of turpentine,
• metals (nickel sulphate, cobalt chloride),
• 2-hydroxy-5-octanoylbenzoic acid,
• capryloyl salicylic acid,
• β-lipohydroxy acid,
• methylchloroisothiazoline/methylisothiazoline,
• methyldibromoglutaronitrile trimethylbenzenepropanol

Products to Avoid that Contain these Chemicals:

• perfume
• body soap
• hand wash
• shampoo
• sunscreen
• deodorant
• hair spray
• nail polish/ remover, lotion/mist)
• household cleaning
• room/ car freshener
• laundry/ dish detergents
• dryer sheets
• incense sticks
• scented candles
• essential oil diffusers
• fragrant pens

Summary of Health Hazards

Artificial fragrances may pose several health risks due to the toxicological profiles of the chemical constituents used. Here are some scientifically backed concerns:

1. Respiratory Issues:
• Mechanism: VOCs and other chemicals in artificial fragrances can act as respiratory irritants.
• Evidence: Studies show that exposure to these compounds can exacerbate conditions like asthma and allergies¹.
2. Endocrine Disruption:
• Mechanism: Chemicals like phthalates and parabens can interfere with hormone function by mimicking or blocking endocrine signals.
• Evidence: Research indicates that these chemicals can disrupt hormonal balance, potentially leading to reproductive issues and developmental problems².
3. Skin Irritation and Sensitization:
• Mechanism: Many synthetic fragrance compounds are allergens and can induce contact dermatitis.
• Evidence: Dermatological studies have shown a correlation between synthetic fragrance exposure and increased rates of skin irritation, rashes, and allergic reactions³.
4. Neurotoxicity:
• Mechanism: Some synthetic musks and other fragrance chemicals can accumulate in human tissue and have been linked to neurotoxic effects.
• Evidence: Laboratory studies have demonstrated that certain synthetic musks can be neurotoxic, potentially affecting cognitive functions and neurological health⁴.

Conclusion

The use of artificial fragrances involves exposure to a variety of chemical compounds that pose significant health risks, particularly concerning respiratory health, endocrine disruption, cancer, skin irritation, and neurotoxicity. While not all individuals will experience adverse effects, those with preexisting conditions or sensitivities should take particular care and avoid all exposure.

Links to more information:

"Fragrances Are Everywhere and Can Trigger Severe Brain Fog" - UT Health

Video Content

Is Traffic Annoying or is your Car Air Freshener POISONING Your Health?

Dr. Axe on Synthetic Frangrances

References

1. American Lung Association ↩
2. Environmental Working Group ↩
3. Journal of the American Academy of Dermatology ↩
4. National Institute of Environmental Health Sciences ↩
5. Rádis-Baptista, G. (2023). Do synthetic fragrances in personal care and household products impact indoor air quality and pose health risks?. Journal of xenobiotics, 13(1), 121-131.
6. Patel, S. Fragrance compounds: The wolves in sheep’s clothings. Med. Hypotheses 2017, 102, 106–111. [CrossRef] [PubMed]