A recent medical report has sparked a raging debate in the medical fraternity; experts in male fertility notably as it has been reported that over the last few decades, a decline has been witnessed in human sperm count and that it is consistent throughout the globe. 

The same was reported via an updated review of medical literature and has caught the researcher’s attention. If true, these findings have resounding and vital implications for human reproduction. 

Researchers also opine that this could also point to the fact that the same could also be an indication of declining health among men in general since the quality of semen in men is an important marker to gauge their overall health.

Over The Years

A rising global trend in infertility has been observed in the past few years, with male infertility arising as a significant problem. One primary reason for the rise in male infertility cases is declining semen quality. 

According to medical research, it has been established that any factor that affects semen quality can affect male fertility. 

Apart from the fact that excessive smoking and drinking, stress, a sedentary lifestyle, and diet all can affect sperm quality but there are also several modifiable factors affecting semen quality, including occupational hazards, air pollution, use of pesticides and harmful chemicals, exposure to excessive heat, and even climate change that can lead to decreased male fertility.

Statistics

• Globally, infertility affects around 8–12% of couples, with male factors being the primary cause in 50% of cases.

• Approximately 7% of all men worldwide are affected by male infertility.

• Many factors predispose to male infertility, including congenital malformations and hormonal, genetic, behavioural, environmental, and lifestyle factors. 

• Environmental pollution has emerged as a significant cause for the rising trend of male infertility worldwide due to the universal presence of environmental contaminants. 

• Recent studies have revealed that air pollution significantly impacts human fertility and sperm quality.

• Semen quality is the primary predictor of male fertility outcome.

• It was observed that environmental pollution unfavourably affects semen quality by impairing the process, thereby leading to decreased male fertility.

Environmental factors: Why Men In India Are Particularly At Risk

Air pollution

In recent years we have seen an alarming rise in air pollution in many cities of the world, which has affected human health to a large extent and has also led to an increase in the number of diseases, including respiratory, cardiovascular, skin-related, cancers, and reproductive disorders. 

Furthermore, India is the second most populated country and the third most air-polluted country globally, the primary sources of air pollution are motor vehicle exhaust, factories, fire, household, agriculture, waste treatment, oil refineries etc., and thus, men in India are particularly vulnerable than those in the west.

Numerous recent researches have shown the adverse effect of air pollution on reproductive outcomes in both males and females; however, it seriously affects the semen quality in males.

Air pollution is one major factor in today’s era resulting in defective spermatogenesis, increased sperm DNA fragmentation, reduced motility, and abnormal morphological changes, leading to a rise in male infertility.

Exposure to harmful chemicals, Occupational Complications

Human beings all over the world are exposed to a wide variety of chemicals in their day-to-day life. Many of these chemicals have serious ill effects on the functioning of the human body, especially reproductive organs. Recent studies have shown that male reproductive organs are affected by exposure to environmental chemicals leading to male infertility.

Dioxins

Dioxins are a group of highly persistent lipophilic chemicals produced as a by-product of several industrial and natural processes, including smelting, chlorine bleaching of paper and pulp, in creating some pesticides, biomedical and plastic waste incineration. 

They are of concern because of their highly toxic nature and ability to get absorbed by fat tissue and stored in the body for long periods (7–11 years). They are known to cause serious reproductive, developmental, and cancer problems. 

Plastic contaminants (Bisphenols): Plastic use has become indispensable in our daily lives, but being non-biodegradable, it has become a significant cause of concern worldwide. 

Bisphenol A (BPA), a major component of plastic, is released into the environment during the process of production, use, or disposal of plastics and from the breakdown of industrial plastic-related wastes resulting in altered reproductive system functions.

Increased exposure to BPA results in sperm DNA damage, mitochondrial dysfunction, degeneration, decreased sperm motility, and sperm count. Hence, prolonged exposure to BPA in excessive concentrations can affect male fertility.

Pesticides and herbicides, Industry

Pesticide exposure can result in defective spermatogenesis leading to reduced sperm concentration, sperm motility, and an increased number of morphologically abnormal sperms, causing poor semen quality and decreased male fertility.

Pesticides such as DDT persist in the environment for years after use and are known as ‘legacy pesticide’ and still can harm male fertility. 

Phthalates

Phthalates, or Phthalic acid diesters, are manufactured chemicals used in several consumer and industrial goods.

They are universally present environmental chemicals commonly found in many consumer products such as toys, pharmaceuticals, cosmetic products, building and construction materials, scent retainers, some medications, personal care products, etc. They are known for their anti-androgenic activity. 

Phthalate gets easily absorbed in the human body through ingestion, skin, or inhaling contaminated air. It causes a wide array of male reproductive organ dysfunction known as “phthalate syndrome”, comprising diminished anogenital distance, infertility, low sperm count, undescended testes, hypospadias, and many other reproductive-tract anomalies.

Heavy metals Industry

Another widespread environmental pollutant that can affect male fertility is non-essential heavy metals, such as lead, cadmium, arsenic, mercury, barium, etc. These heavy metals can adversely affect the semen and sperm quality in men.

Heat exposure Due To Occupation Or Climate Change

Another major factor that may contribute to male infertility is exposure to excessive heat at the workplace or due to climate change. Temperature plays a crucial role in maintaining normal spermatogenesis in testes, and environmental stresses, such as a temperature rise, activate heat shock protein (HSP).

Exposure to high temperatures, as seen in cases of occupational exposure to radiant heat in people working in furnaces, bakeries, welding or ceramic factories, those working for long hours in kitchens, laundries, dry cleaning shops, or drivers can result in loss of thermoregulatory function of scrotum affecting one or more component of semen quality in males.

Hence, exposure to high temperatures due to occupation and environmental factors has a harmful impact on overall semen quality and can cause male infertility.

Conclusion: Environment plays a crucial role in male fertility. Adverse environmental factors can result in poor semen quality, leading to male infertility. 

However, all these factors can be prevented or modified, allowing us to decrease their risk. Reducing air and chemical pollution, heat exposure and bringing positive changes in our daily lifestyle can prevent these adverse impacts on semen quality to a large extent, thereby reducing the overall incidence of male infertility.

Hence the lifestyle choices you make can significantly impact your entire health and well-being. Most lifestyle choices, age, food, exercise, weight, stress levels and sleep quality are associated in some way with fertility, where physical and mental health, occupational and environmental exposures, substance use and abuse and medications also impact male fertility.