What Are The Health Effects of Over-Sanitization?

Specific effects of sanitization chemicals on human health
The COVID-19 pandemic and the potential health consequences associated with the use of alcohol-based hand sanitization products
References 
Further reading 

Using cleaning agents in disinfection products is thought to produce various outcomes associated with several organ systems, including respiratory and cardiovascular symptoms and effects on the skin. The respiratory effects can range from acute temporary open airway irritation to two obstructive lung diseases.

Specific effects of sanitization chemicals on human health

There are several organs and systems which are affected by chemicals present in sanitization products.

Impaired respiratory function

Respiratory ailments are the most common health problem arising from chemicals present in sanitization products. It has been demonstrated that early exposure to large doses of cleaning chemicals can result in detrimental and long-term respiratory function, increasing the risk of childhood asthma as a consequence of epithelial lung cell damage mediated through the innate immune pathways. Bleach, glutaraldehyde, and ethanol are known to cause respiratory irritation, exacerbate existing asthma present, or trigger what is known as “occupational asthma.” Fragrances that also accompany the ingredients in sanitization products are also triggers for respiratory disorders.

Liver and kidney damage

QACs, which are disinfectants used in workplaces and healthcare settings, are thought to be directly toxic to the immune system due to compromising the phagocytotic function of macrophages. This is also a similar concern associated with the use of glutaraldehyde. However, the immunotoxicity of this agent has not been adequately assessed.

Metabolic health and obesity

Research has indicated that anthropogenic chemicals can produce long-term consequences such as problems with hormonal function and regulation of body weight in animals and humans. Cleaning chemicals may be considered obesogenic; the predominant mechanism through which cleaning chemicals compromise hormonal balance and promote obesity is through the alteration of the gut microbiome.

A study that evaluated the gut microbiota of infants between the ages of three and four months relative to the composition at one and three years of age demonstrated that alterations in the microbiota of the gut had a strong association with increased household disinfectant use. Concurrently, children exposed to heavier disinfectants also had higher body mass indexes at age three than infants who were less exposed.

Thyroid function

Phthalates are common chemicals found in sanitization products and are thought to impair thyroid function. Prenatal phthalate exposure has been shown to decrease total thyroxine (T4) levels in pregnant women, which may subsequently produce adverse effects on fetal development and the subsequent health of the infant.

Notably, a study has demonstrated that even small doses of phthalate triclosan can destroy thyroid function in mice due to suppressed hypothalamic gene expression. Despite these observations, the biological mechanisms through which phthalates exert their effects remain to be elucidated in full – though it is believed that phthalates may interfere with the binding of T3 to transthyretin, a binding protein that transports both T3 and T4 in the blood to target tissues.

Reproductive health

Cleaning products are thought to reduce fertility due to studies that indicate such effects. A study of female nurses found reduced fertility among those who reported high levels of disinfectant use. In animal models, it has been found that exposure to QACs results in declined fertility via reduced sperm count and motility in male organisms and the inhibition of ovulation and fertilized egg implantation in female organisms.

Similarly, fragrances in cleaning products have been shown to demonstrate toxic effects on sperm, decreasing their viability. Phthalates have a similar effect on male reproduction. QACs have also been linked to neural tube defects, or congenital disabilities of the brain and spinal cord in animal models, demonstrating that some cleaning product constituents can pose a risk to a developing fetus. Poor health outcomes for the baby have also been predicted as a consequence of phthalate-mediated disruption of fetal reproductive system development in utero, which may trigger premature delivery.

Brain health

Acute problems associated with sanitization include headaches; however, it is largely considered an innocuous effect. Despite this, a growing body of research indicates that some chemicals may harm the brain through several mechanisms. For example, perinatal exposure to triclosan has been found to alter brain development and behavior in infant mice.

Phthalates have also demonstrated the triggering of cognitive dysfunction due to increased oxidative stress in the brain. Furthermore, VOCs, gases emitted from various products, are known to readily pass through the blood-brain barrier, where they can enter into the central nervous system, producing toxic effects on brain cells.

The microbiome

The microbiome present on the skin, nasopharyngeal, and gastrointestinal membranes are vulnerable to excessive sanitization products use. Principally, these products disrupt the balance of various species of microbes and disrupt the harmonious process of environmental exchange that occurs with the environment that shapes the microbial population. Over-sanitization of indoor environments could reduce the diversity and resilience of microbial communities. As these populations are crucial for regulating health through their multifaceted effects on the immune, metabolic, and endocrine systems, depleting these populations may have downstream, sizable, and systemic negative effects on the body.

Specifically, phthalates are known to inhibit the intestinal synthesis of butyrate, which is an integral component open showing robustness of intestinal epithelial cells, which interacts with other gastrointestinal microbes to produce a functional and healthy microbial landscape. Moreover, SLS, a detergent and surfactant found in several sanitization products, is known to reduce the skin barrier integrity due to disrupting the skin microbiome.

The COVID-19 pandemic and the potential health consequences associated with the use of alcohol-based hand sanitization products

Hand hygiene is typically a crucial measure to prevent the spread of viruses and bacteria. This has been illustrated most notably during the COVID-19 pandemic. The World Health Organisation (WHO) has proposed, among several preventative measures, to adapt to effective hand hygiene; in line with this, the WHO Recommends washing or disinfecting hands frequently with soap or 60% alcohol-based hand sanitizer.

These recommendations are based on their ability to produce fast, effective, and broad-spectrum antibacterial activity. The alcohol-based sanitizer recommended by WHO comprises ethanol, isopropanol, and several types of hydrogen peroxide. However, these agents are toxic to both human health and the environment.

Alcohol-based sanitization products contain isopropanol. It is believed that alcohol causes disintegration of RNA, denatures viral proteins, and interferes with membrane integrity. Skin contact with ethanol-based hand sanitizers is associated with low toxicity. However, different people show different responses with regard to the tolerance levels of ethanol.

When in contact with the skin, it may cause eye and skin irritation as well as allergies. Prolonged contact can result in skin dryness or cracking, and itching or redness. It may also cause contact dermatitis if used regularly. Ethanol can build up in the respiratory system, causing respiratory depression and arrest, hypothermia, arrhythmia, ketoacidosis, hypoglycemia, and hypotension, with the possibility of cardiac arrest. Ethanol exposure can cause acute liver damage, myoglobinuria, and elevated potassium, calcium, and magnesium.

Therefore if ethanol-based products are used consistently, this prolonged use can cause harm to health as a result of skin absorption and poisoning. In a review of medical outcomes of disinfectant cases between January 2020 and September 2020, major, moderate, and minor effects caused by those using alcohol-based sanitizer were 0, 6, and 25%, respectively.

References

• Steinemann A. (2016) Fragranced consumer products: exposures and effects from emissions. Air Qual Atmos Health. doi:10.1007/s11869-016-0442-z.
• Malaguarnera G, Cataudella E, Giordano M, et al. (2012) Toxic hepatitis in occupational exposure to solvents. World J Gastroenterol. doi:10.3748/wjg.v18.i22.2756.
• Anderson SE, Meade BJ, et al. (2014)  Potential health effects associated with dermal exposure to occupational chemicals. Environ Health Insights. doi:10.4137/EHI.S15258.
• Differding MK, Mueller NT. (2018) Are household disinfectants microbially mediated obesogens? CMAJ. doi: 10.1503/cmaj.181134.
• Dodson RE, Nishioka M, Standley LJ, et al. (2012) Endocrine disruptors and asthma-associated chemicals in consumer products. Environ Health Perspect. doi:10.1289/ehp.1104052.
• Cao XY, Hua X, Xiong JW, et al. (2018) Impact of Triclosan on Female Reproduction through Reducing Thyroid Hormones to Suppress Hypothalamic Kisspeptin Neurons in Mice. Front Mol Neurosci. doi: 10.3389/fnmol.2018.00006.
• Melin VE, Potineni H, Hunt P, et al. (2014) Exposure to common quaternary ammonium disinfectants decreases fertility in mice. Reprod Toxicol. doi:10.1016/j.reprotox.2014.07.071.
• Hrubec TC, Melin VE, Shea CS, et al. (2017) Ambient and Dosed Exposure to Quaternary Ammonium Disinfectants Causes Neural Tube Defects in Rodents. Birth Defects Res. doi: 10.1002/bdr2.1064.
• Mitro SD, Johnson T, Zota AR. (2015) Cumulative Chemical Exposures During Pregnancy and Early Development. Curr Environ Health Rep. doi:10.1007/s40572-015-0064-x.
• Velazquez S, Griffiths W, Dietz L, et al. (2019) From one species to another: A review on the interaction between chemistry and microbiology in relation to cleaning in the built environment. Indoor Air. doi:10.1111/ina.12596.
• Mahmood A, Eqan M, Pervez S, et al. (2020)COVID-19 and frequent use of hand sanitizers; human health and environmental hazards by exposure pathways. Sci Total Environ. doi:10.1016/j.scitotenv.2020.140561.

Further Reading

• All Healthcare Content
• Healthcare Systems Around the World
• What is the Role of Regulatory Bodies in Healthcare?
• How is the ‘omics’ Revolution Changing Healthcare?
• Primary Healthcare Providers

Written by

Hidaya Aliouche

Hidaya is a science communications enthusiast who has recently graduated and is embarking on a career in the science and medical copywriting. She has a B.Sc. in Biochemistry from The University of Manchester. She is passionate about writing and is particularly interested in microbiology, immunology, and biochemistry.