Abstract
Human infertility is increasing at an alarming rate and has affected nearly 12% of reproductive aged couples worldwide. Various reasons have been linked to its cause, besides the age of female partner, a huge number of environmental contaminants produced and used by humans throughout the world are one of the reasons for growing the infertility rate. Their exposure is virtually unavoidable. The literature review provides an overview regarding the effect of chemical agents on fertility. The environmental contaminants included in this review are plastics, pesticides, phthalates, metals, industrial chemicals, endocrine disrupters, and nano materials. The goal is to discuss the association between environmental contaminants and reproductive disorders with particular emphasis on infertility.
TopPlastics
Plastic plays an imperative role in everyday life and everyone is involved with plastic made products in different ways. Plastic is being used indispensably in our lively hood materials such as health, agriculture, automotive, construction and textiles (Andrady, 2011; Andrady and Neal, 2009; Dris et al., 2015). Plastic reliability is increasing by every single day because of its variety characteristic feature. The potential for diverse applications, including widespread use of disposable items and the durability of plastic is anticipated, but the associated problems of waste management and plastic debris are not (Yarsley and Couzens, 1945). Studies have revealed that the long term use of plastic containers can increase health risks. Plastic containers or bottles are composed of different chemicals such as phthalates, Bisphenol A (BPA), brominated flame retardants, antiminitroxide, and poly-fluorinated chemicals etc., which are a serious risk factor for health (Halden, 2010). BPA is a xenoestrogen, and having the structural similarity with estrogen can therefore bind with the estrogen receptor site. Various evidences have indicated the adverse impact of BPA on human fertility and is also responsible for the reproductive pathologies, e.g., cryptorchidism, cancers, testicular dysgenesis syndrome, follicle loss in female and decreased fertility in male. BPA has been found to bind to estrogen receptors but still it is less potent than estradiol. BPA also binds to the androgen receptor (AR) and act as its antagonist when its level is high (Rochester, 2013; Wisniewski et al., 2015; Lucas et al., 2009; Zhou et al., 2017). European Chemicals Agency 2017, listed BPA as a substance of concern because of its endocrine disruptor properties.
Key Terms in this Chapter
Testicular Dysgenesis Syndrome: The malformations of the male reproductive organs beside damaged semen quality, lower testosterone production and testicular germ cell cancer, constitute a syndrome of testicular dysgenesis (TDS) with a common origin in fetal life.
Phthalates: A family of chemical compounds used in hundreds of products mainly as plasticizers, increase the flexibility, transparency, durability, and longevity to plastics.
Xenoestrogen: Substances that are close enough in molecular structure to estrogen also called as “foreign” estrogens, can bind to estrogen receptor sites with potentially hazardous outcomes.
Sterility: It’s the physiological inability to produce offspring or to conceive a child.
Cryptorchidism: A condition in which one or both testes hasn't moved into the scrotum before birth.
Pesticides: A group of chemical substances that are used to kill, repel, or control the pests including rodents, insects, certain forms of plants and fungi.
Infertility: It is the inability of a couple to reproduce naturally or we can say not able to get pregnant.
Epidemiology: The study of the distribution and determinants of health-related states and events in specified populations and the application of this study to the control of health problems.
Spermatogenesis: A process of formation of male germ cells in the testis.