Written by Ben Bunting: BA(Hons), PGCert.
There are numerous threats to male fertility that have been linked to environmental toxins. These include Arsenic and DDT, both of which disrupt endocrine function. Other environmental toxins that have been linked to male fertility issues include Cadmium and noise pollution.
Arsenic affects male fertility
Endocrine disruptors, including arsenic, are known to affect various biological processes. For example, arsenic affects male fertility by affecting spermatogenesis, a complex process in which sperm and ovum merge to form an embryo. Some of the endocrine disruptors are known to alter the activity of a particular enzyme called glutathione peroxidase (GPx4), which has been shown to be crucial for spermatogenesis.
Studies have shown that exposure to arsenic can cause a reduction in sperm count and motility. It also reduces the synthesis of testosterone, which is essential for spermatogenesis. This results in low-quality sperm.
Arsenic exposure can also cause reproductive toxicity in both males and females. It can alter the tissue architecture of the sperm and ovaries and cause a decrease in testosterone synthesis. Furthermore, arsenic can increase the risk of prostate cancer.
Arsenic is one of the most toxic chemicals in the environment. It is ubiquitous in the earth's crust and is present in high concentrations in drinking water. It has been linked to a variety of diseases, including cardiovascular diseases and cancer. However, the World Health Organization has recommended that humans not consume more than 10 mg/L of arsenic in their drinking water.
Researchers have shown that heavy metals are toxic to humans and animals and have an adverse effect on fertility. The number of studies on heavy metals and male fertility is low, but evidence exists that they can reduce the quality of seminal fluid and cause infertility.
Arsenic is suspected of affecting male fertility through the ERK/AKT/NF-kB pathway. Previous research has also demonstrated that arsenic can increase phosphorylation of ERK1/2. It has also been shown to increase levels of AKT and NF-kB.
DDT disrupts endocrine function
The endocrine-disrupting chemical DDT has been linked to low male fertility in several species of animals. The chemical has been known to cause apoptosis of Leydig cells, which lower testosterone levels in the body. It is one of many environmental pollutants that affect the endocrine system. Specifically, it has been found that pesticides can disrupt the MAPK signaling pathway, which leads to erectile dysfunction in males. This pathway is mediated by Erk1/2 and p38 MAPK, which lead to a breakdown of the blood testes barrier, a decrease in testosterone, and weakening of the seminiferous epithelium.
EPA guidelines define endocrine disruptors as substances that interfere with natural hormones in the body. These chemicals interfere with reproduction and homeostasis, as well as other aspects of development. They are present in products that you use every day, from detergents to cosmetics. They also have negative effects on aquatic life. Studies have shown that endocrine-disrupting chemicals are associated with reproductive problems in fish and amphibians.
DDT is one of the most widely used pesticides in the world, and it has been linked to reproductive dysfunction. It has been shown that DDT affects reproductive function through a variety of mechanisms, including disruption of sperm quality and development, mitochondrial dysfunction, and oxidative stress.
In addition to disrupting reproductive function in animals, exposure to EDCs can impact future generations through transgenerational inheritance. Exposure to these compounds can lead to a variety of reproductive disorders in humans, including aneuploidy.
Cadmium interferes with spermatogenesis
Cadmium, one of the most common environmental contaminants, has been associated with reduced sperm motility in laboratory animals. Its effect is thought to be due to disturbed hormone production. Specifically, cadmium decreases serum testosterone and inhibits steroidogenic enzymes. This environmental heavy metal has long been known to affect the reproductive system, and it is found in virtually every location in our environment. In addition to causing a range of physical damage, cadmium also inhibits the production of testosterone, reducing sperm counts and increasing DNA damage.
Human exposure to mercury is primarily from seafood, although it is also present in certain dental compounds and skin-lightening creams. In one systematic review, researchers found that higher levels of mercury in the environment were associated with lower sperm quality and increased occurrence of spontaneous abortions in men. They also found that elevated levels of mercury in the blood were associated with higher rates of sperm quality and DNA damage.
Cadmium is known to boost oxidative stress, which may contribute to its toxic effects on the endocrine system in humans. To study the effects of cadmium on glycemic control and oxidative stress markers in male adolescents, researchers conducted a study involving 111 males aged 12-14 years in a polluted area in Sicily, as well as 60 healthy males living 28-45 km away from the polluted area. The subjects were then assessed for insulin resistance and homeostasis using a homeostatic model assessment.
There are many environmental pollutants that may threaten male fertility. SNBP, a protein that has been implicated in oxidative damage in spermatic DNA, is one of these. This alteration results in altered DNA binding pattern and altered sperm chromatin organization, which is critical to successful fertilization.
Noise pollution affects sperm counts
Noise pollution affects the number of sperms in a man's testicles, which can lead to a lower sperm count and decreased male fertility. It also affects the motility of sperm. Noise, vibration, lighting, and microwave exposure can negatively affect male fertility.
A healthy environment for men should be free of noise. Noise from traffic, airplanes, and trains can disrupt sleep and cause infertility. In one study, men exposed to 55 decibels of noise at night had lower sperm counts than men who were not exposed to the same levels of noise. It is unclear whether a single exposure to a high enough level of noise will affect sperm counts, but long-term exposure to high levels of noise is believed to increase male infertility.
The association between RF-EMR exposure and sperm motility has not been clearly established, but studies on animals suggest a negative connection. Nevertheless, the findings of the present study are consistent with other findings. RF-EMR exposure decreases sperm motility and causes DNA fragmentation.
Noise pollution can also decrease sperm motility and testosterone levels. The exposure of men to noise has been found to reduce serum levels of testosterone, the primary hormone responsible for sperm production. Furthermore, it reduces the concentration of luteinizing hormone in the blood. This effect may be due to increased levels of cortisol in the blood.
Environmental pollutants that affect male fertility include diesel exhaust, which reduces testis size and sperm production. It affects the aryl hydrocarbon receptor, which is also affected by cigarette smoke and other sources of smoke. This effect may be due to a similar mechanism to dioxin, which was found in the Seveso oil spill in 1976.
Pesticides affect spermatogenesis
Recent research suggests that exposure to pesticides may affect male fertility. Long-term exposure to pesticides may cause alterations in male hormone levels, including sperm concentration and motility. Excessive exposure to pesticides may also reduce the number of sperm.
Many studies have examined pesticides' effect on male fertility and spermatogenesis. However, many of these studies have used multiple pesticides and so are difficult to interpret. Some studies have found that pesticides negatively affect sperm quality, while others have found no impact. Regardless of the pesticides used, additional studies are needed to understand exactly how pesticide exposure affects spermatogenesis and male fertility.
Although most studies involved laboratory animals, humans can be a more complex organism. While most studies on chemical compounds in laboratory animals use high doses of a chemical, human exposure to these chemicals is much more complicated. In addition, a human male's spermatogenesis profile varies enormously. There is a complex interplay between ECs in the environment and sperm count, making it difficult to determine which compound has the most impact on male fertility.
In adults, the production of sperm depends on the number of germ cells in the Sertoli. Sertoli cells can only support a limited number of germ cells, depending on species. The number of Sertoli cells increases during the foetal and postnatal period, and is required for adult spermatogenesis.
While spermatogenesis requires a limited amount of room for manoeuvre, exposure to adverse environmental factors is highly likely to disrupt the process. This may explain why sperm counts have declined in recent decades. However, this is not conclusive as it may be caused by genetic or lifestyle factors.
A growing body of research has linked environmental toxins with male fertility decline. PFAS, or Perfluorinated Acids, are endocrine disruptors, which mean that they interfere with the production of natural male hormones. This can lead to reduced sperm count, motility, and semen quality. Furthermore, these compounds may affect male fertility in the womb, where adequate testosterone levels are necessary to ensure fertile fetuses.
One systematic review of environmental pollutants showed that air pollution can influence sperm quality parameters, including DNA fragmentation and impaired motility. However, the included studies were highly heterogeneous, making direct comparison of results difficult. However, three studies showed a significant association between air pollution and poor sperm quality, while six studies showed a link between air pollution and decreased sperm count and abnormal sperm morphology.
Heavy metals, such as lead, have also been implicated in male fertility problems. The American Chemical Society estimates that occupational exposure to heavy metals could cause a decline in sperm concentration. Occupational exposure to these chemicals is common in industries such as smelting, mining, and welding.
Environmental toxins are ubiquitous and affect vulnerable populations. Even preconception exposure to these agents can increase the risk of developing cancer, a potentially life-threatening condition. In addition, pesticides have been linked to sterility and prostate cancer in adult males. Exposure to these chemicals during pregnancy can also interfere with the developmental stages of female fertility.