Environmental Impacts on Male Fertility
WHY AVOIDANCE IS BEST AND WHAT TO DO IF AVOIDANCE IS UNAVOIDABLE
Don’t forget about the sperm! Women are often at the forefront of infertility conversations, but up to 35% of infertility cases involves the male partner. Sperm production is a leading cause of male infertility, but 20% of male infertility is categorized as idiopathic, which occurs when men have a seemingly normal semen analysis but are still infertile. Research is showing that sperm health has been declining over the last several decades and overall conception rates are lower as well. One possible cause for the declining health of sperm may be due to environmental pollutants. Exposure to various toxins in the air, in our houses, and in the workplace is unavoidable and the negative effects on fertility rates is reflected in the literature. Environmental exposure to toxins often has a chronic low-level effect on health and may not always be picked up by blood work and testing. Although not always obvious, environmental exposures could be a key reason why male semen quality and quantity has decreased over time. Some key pollutants that have been linked to male infertility include bisphenol A, phthalates, and heavy metals.
BISPHENOL A (BPA):
Bisphenol A (BPA) is a synthetic compound and is found in many household and food objects including canned foods, food packaging, and plastic objects such as toys. BPA is a known endocrine disruptor, which means it can bind to estrogen receptors in the body and cause harmful effects. Various endocrine hormones regulate the male reproductive system, and a proper balance of these hormones is needed for optimal fertility. BPA has been found to decrease overall testosterone production and this disruption in hormonal activity can lead to altered spermatogenesis, sperm transport, and sperm storage. BPA has also been linked to decreased sperm concentration, decreased motility, abnormal morphology, and decreased total sperm count.
What does the research say?
- Studies have found that BPA levels are higher in infertile men compared to healthy controls.
- Sperm concentration and count were inversely related to BPA levels in seminal fluid.
- One study examined 308 men and found that BPA was detectable in 98% of urine samples and participants with the highest levels of BPA had significantly lower sperm motility.
PHTHALATES:
Another common environmental exposure is found in phthalates. Phthalates are synthetic chemicals that are commonly used as plasticizers in many commercial products. Phthalates increase plastic flexibility and are ubiquitous in the US population. Common sources of phthalates include food packaging, vinyl flooring, perfume, deodorant, and nail polish. Phthalates may cause DNA damage to sperm and increased oxidative stress.
- One study found that phthalate exposure was related to DNA damage of sperm and a 20% reduction of fertility was observed.
HEAVY METALS:
Heavy metal exposure is known to have a toxic effect on the human body. Exposure to heavy metals mainly come from environmental, dietary, and occupational sources. Lead and cadmium are two heavy metals that have been consistently linked to male infertility due to their accumulation in male reproductive organs. Increased lead exposure has mainly been associated with lower sperm count. Possible mechanisms include detrimental effects on testicular function and hormone alterations. Cadmium is another heavy metal that contributes to male infertility and is a known endocrine disruptor. Smoking and occupational exposure are two common sources of cadmium, but there are many other environmental sources including dietary, pollution, and contaminated water.
- One study examined the seminal fluid of infertile and fertile men and measured seminal cadmium levels and semen parameters including sperm concentration and motility. Statistically significantly higher cadmium levels were found in the infertile group of men, suggesting that cadmium toxicity may contribute to male infertility. Additionally, those with the highest levels of cadmium had both lower sperm count and motility.
WHAT TO DO:
Avoidance is the best practice for treatment when there is exposure to environmental pollutants. There are several ways to limit exposure in the household. One of the best ways to decrease exposure to BPA and phthalates is to cook and store food in glass containers instead of plastic and minimize use of plastic Ziplock bags. It’s also a good idea to buy organic food as much as possible, since many pesticides and other toxins are found in non-organic foods, especially in produce and dairy products. Other easy ways to decrease household exposure to toxins include drinking filtered water, running the fan when using gas appliances, and switching to more natural cleaning products and bath/beauty products. Finally, it is helpful to make sure house filters are cleaned regularly and carpets are vacuumed to remove toxic particles that circulate through the house.
INTERVENTIONS:
Additional ways to decrease toxin effects of environmental pollutants include lifestyle modifications, detoxification, and supplementation with antioxidants. Detoxification is a powerful tool to utilize if you have a known exposure to toxins or heavy metals. Easy detoxification techniques include eating cruciferous vegetables such as broccoli, cauliflower, or Brussel sprouts, and sweating though exercise or sauna use. The metabolism of toxins and heavy metals cause a high amount of oxidative stress on the body and the production of reactive oxygen species (ROS). Supplementation with antioxidants can neutralize the detrimental effects and possibly increase semen quality.
- One study found a positive correlation between antioxidant use and sperm health, successful assisted reproductive therapy, and live-birth rate.
Examples of antioxidants include dark-colored berries such as blueberries, vitamin C, and selenium (found in brazil nuts). If you or your partner are hoping to conceive, minimizing environmental toxin load may be a helpful place to start. What are ways that you have worked toward decreasing environmental exposures? Drop a comment below!