Is It in your cosmetics and skincare products?
By Dr. Peter Dingle, BEd, BSc, PhD
Triclosan (TCS) is another one of those chemicals found in personal care that is finally on its way out, even though we have known of its toxic effects for decades.
After many decades of scientific scrutiny many companies are now removing TCS. Colgate removed it from its Softsoap liquid hand soaps and Palmolive antibacterial dish liquid in 2011.
The big companies continue to deny TCS is a problem, and claim they are phasing it out because of public concerns, citing changing consumer preferences and superior formulations.
Triclosan is a biocide used as an antibacterial and antifungal agent in a number of consumer products such as toothpaste, mouthwash, disinfectants, soaps, hair products, skin creams (0.1%), feminine hygiene products, and cosmetics. Personal care products and cosmetics are the major source of exposure and studies on human subjects using TCS-containing cosmetics showed variable but significant amounts of TCS.
Research suggests that beyond its use in clinical applications (in hospitals) and toothpaste to prevent gingivitis (Gunsolley, 2006) there is questionable evidence that TCS provides any extra benefit in other consumer products.
Should we trust labels?
Unfortunately, what is on the label is not always what is in the products and it has been detected in conventional dish liquid products at low concentrations, although it was not listed on the product labels. So should we trust labels?
Because of such widespread use in cosmetics, personal care and cleaning products TCS is also one of the more frequently detected and highly concentrated contaminants in aquatic and terrestrial environments, particularly in drinking water, and is among the top seven organic wastewater contaminants in the United States. (Kolpin et al 2002).
Looking at the chemical structure of TCS implies that it may have chemical properties related to many toxic compounds, such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), bisphenol A (BPA) and dioxins (Allmyr Sci Total Environ. 2008).
Given the prevalence of TCS in the environment, it is not surprising that measurable levels have been detected in just about every person, even if you don’t use products with it on the label.
It is commonly found in found in body fluids such as amniotic fluid, blood, breast milk and urine and was also found in human tissues such as adipose tissue, brain, liver and nails (Geens et al.2012).
The high TCS concentrations in the tissues relative to the environmental concentrations suggests that TCS bio-accumulates and is distributed all through human tissues. Other chemicals such as Propylene glycol, which is commonly found in the same product, has been shown to increase skin absorption of TCS (Fang et al. 2014).
Interestingly, in one study TCS concentrations were a factor of 2 higher in Australian serum than in the Swedish plasma samples (Allmyr et al. (2008), probably because of the discouragement to use TCS-containing products by the Swedish government and the lack of concern from the Australian authorities.
Moreover, TCS has been detected in amniotic fluid, indicating that TCS can enter the fetal environment through placental transfer (Philippat et al 2013).
Fetal life is considered a particularly vulnerable period for exposure to endocrine-disrupting chemicals because hormonal disturbances during organ development may introduce irreversible changes (MacLeod et al 2010). Studies on pregnant rats have also reported the greatest bioaccumulation of TCS was observed in the placenta and that the hormone disruption might subsequently affect fetal development and growth (Feng et al. 2016).
Breast-feeding infants represent a major route of exposure to TCS. In highly industrialised countries, elevated concentration in breast milk is common (Dayan 2007). This is of major concern, because the immature metabolising pathways of infants makes them particularly vulnerable to the negative impact of TCS. Not to mention they may be relying on just one source of food.
Moreover, levels of TCS in breast milk may be increased by underarm cosmetic use, which presents a direct dermal route of exposure to underlying epithelial tissue (Darbre, Best Pract. Res. Clin. Endocrinol. Metab. 2006). In addition, a study of Swedish women who are users of personal care products containing TCS had higher concentrations in milk and serum than women who use similar personal care products that presumably contain no TCS (Allmyr et al. (2006), showing that personal care products containing TCS were the dominant, but not the only, source of exposure to TCS.
Similar to all the research on the other environmental estrogens, the latest science has shown that even small doses of certain chemicals can significantly affect hormone functions, if they are delivered at the wrong moment. The endocrine-disrupting properties of TCS including its effects on estrogen, testosterone activity and disturbance of thyroid hormone action at concentrations [are] typically found in the studies on humans and the environment.
Birth defect studies
In humans, recent studies have shown an increasing number of potential birth defects. In a study of 520 male newborns, prenatal TCS exposure was inversely associated with prenatal growth parameters at week 33 and was statistically associated with reduced head circumference at birth (Philippat et al 2014). In another study, Prenatal TCS exposure was associated with reduced head and abdominal circumference at birth, (Harmer Lassen,et al 2014 Environ Health Perspect)
Increasing evidence suggests that TCS plays a role in cancer development, perhaps through its estrogenicity or ability to inhibit fatty acid synthesis (Dinwiddle et al 2014). This includes breast cancer and liver tumours.
The results of these studies suggest that TCS affects cancer cell proliferation, particularly in the presence of estradiol. In male rats, TCS exposure led to decreases in serum testosterone (T), sperm production and male accessory gland weight (Kumar et al Reprod Toxicol. 2009), and reduced ability to reproduce.
Increase in asthma
During the past decade, there has been a remarkable and unexplained increase in the prevalence of asthma. Some have hypothesised that widespread use of antimicrobial ingredients such as TCS may be a contributing factor. This concept is based on the hygiene hypothesis, which proposes that lack of pathogen exposure during development can alter the usual development of the immune system by eliminating or changing the commensal microbiota, which are an important support for health.
There is also increasing evidence of TCS-induced allergic reactions in humans. Dermatitis following prolonged use of TCS-containing hand washes (Wong and Beck 2001) or when further exposed to sunlight after use (Schena et al. 2008) have been recorded. Similarly, blisters were known to have erupted in the mouth and on the lips of human subjects following prolonged use of TCS-containing toothpaste (Robertshaw and Leppard 2007).