Ingestion and Exposure to Common Pesticides Could Be Linked To Early Menstruation and Its Socioeconomic Consequences
By BaoChau Le
Introduction
There are many things that I’ve done that has sent my Vietnamese immigrant mother into a spiral. Covering myself in leeches because I wanted to be ‘paler’ and breaking the nose of one of my male classmates with a football after he told me that ‘girls can’t play football’ are two childhood classics. (Maybe that’s where my passion for gender studies started.) Yet, the one that I remember the most vividly took place in my pediatrician's office when I was in fifth grade. We were there for a routine check-up since it was my eleventh birthday, and I had started my first menstrual cycle. Fortunately, the health presentations at school had already warned me about this, but nothing could have prepared my mother. She proceeded to ask my pediatrician if this was normal, if there was something abnormal about my hormones, and even cried. I remember her telling me things such as “You’re too young to be a woman,” and “You have to be extra careful now.” Eleven-year-old me had no idea why my mother was scared, because school had informed me this was normal and expected. Only now that I’m older do I understand why my mother was terrified. To her this was not just my introduction to ‘adulthood’, but to intimate sexual relationships, marriage, pregnancy, and unfortunately, sexual-based violence.
The start of puberty in females assigned at birth (ASAB) is indicated by the growing of breasts, development of hips, hormonal acne, and the start of their first menstrual cycle. The age at which someone experiences their first menstrual cycle is known as the menarche age. Since the late 1800s, the menarche age has decreased drastically with the average person starting their cycle at age 17 and now at 13 in the early 2000s. Studies have shown that the decreasing of menarche age is disruptive in young girls as it makes them more vulnerable to early marriages, sexual violence, gender-based violence, and poor maternal health. Scientists have contributed many factors to the decrease in menarche age such as genetics, nutrition, access to adequate healthcare, and other socioeconomic factors. One commonly overlooked factor is the relationship between the presence of endocrine disruptor chemicals, such as those found in pesticides, and the decreasing of menarche age.
The Endocrine System
The endocrine system, which is composed of reproductive organs and glands, is responsible for the production of all the hormones that we would need throughout our lifetime, specifically sex hormones. For females ASAB, the endocrine system is responsible for producing and regulating estrogen, the sex hormone that oversees regulation of menstrual cycles, fertility, pregnancies, and the homeostasis of reproductive organs. (National Cancer Institute, n.d) Disruption of the endocrine system tends to happen when endocrine disruptor chemicals (EDCs), are introduced to the body. Once inside of the body, EDCs can bind onto specific hormones or mimic their effects. If EDCs binds onto specific hormones and block the detection of this hormone, then the body would either increase or decrease hormone production, resulting in a hormonal imbalance. If EDCs can mimic hormonal activity, then the body would behave as if there were an increased level of hormones. For example, if a girl around the age of 11 constantly ingested food that was treated with estrogenic EDCs, then her body would eventually react under the premise that there are high levels of estrogen being produced, which is one of the signifiers that menstruation is ready to occur. Since the body cannot differentiate between true estrogen levels and estrogen levels caused by EDCs, it assumes that the young girl is prepared for menstruation.
Commonly used pesticides such as dichlorodiphenyltrichloroethane (DDT), methoxychlor, and endosulfans are notoriously known estrogenic chemicals or chemicals that can mimic estrogen and alter estrogenic activity in the body. These same chemicals can be introduced to the body when someone consumes food or water that has been treated with them. (Environmental Protection Agency, n.d) From there, these chemicals can either flow through the blood stream or settle into tissues throughout the body, formidably altering the hormone levels and disrupting crucial growth stages.
In this paper I will examine how the use of endocrine disruptor chemicals (EDCs) such as DDT, endosulfans, and methoxychlor can result in the decreasing of menarche age. With young girls starting their menstrual cycles sooner, they are also entering marriages at an earlier age. Societal implications of girls being married young include higher rates of sexual violence and gender-based violence. Furthermore, these girls are more vulnerable to adolescent pregnancies and its complications, which in turns negatively impacts their maternal health.
The Silent Disruptor: Pesticides
The three most commonly used pesticides are DDT, methoxychlor and endosulfans. (Ozen, S., Goksen, D., & Darcan, S, 2014) These pesticides are typically sprayed directly onto plants and mixed into soil to kill off any unwanted insects. When people ingest the food that have been treated with these pesticides, it enters the bloodstream, some are able to reside in our fatty tissue for long periods of times, while others dissolve within a few hours. Regardless, all three pesticides have demonstrated the ability to alter our endocrine system.
DDT (dichloro-diphenyl-trichloroethane)
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When it was first synthesized in the late 1950s, DDT was advertised as “benefactor of all humanity.” (Arnold, 2021) It was a multifaceted insecticide that promised farmers freedom from unwanted pests eating away at their crops and civilians’ freedom from malaria, typhus, and other insect-borne diseases. Within the first 20 years of its creation, the United States government sprayed more than 1.35 billion pounds of DDT all across America. (Arnold, 2021) Advertisements for DDT, like the one shown in Fig 2, claimed that DDT made cattle produce more meat and dairy, protects families from insects, and results in more crops grown as all of the bugs were eliminated. DDT was a household item that ensure pesky bugs such as mosquitoes and vector-borne diseases, malaria, did not terrorize American homes. In 1972, the Environmental Protection Agency (EPA) banned the use of DDT after alarming animal studies demonstrated that exposure to DDT could cause development of tumors, affect reproduction, and alter body mass index to cause morbid obesity. (Environmental Protection Agency, n.d) Unfortunately, countries that are malaria and typhus endemic still use DDT frequently. The global usage of DDT as a means of malaria vector control totaled to approximately 5700 metric tons in 2017, with India being the lead producer and user. Troublingly, studies also demonstrated that DDT usage throughout India has decreased the menarche age by at least 1.3 years.
Endosulfans and Methoxychlor
There is a limited amount of comprehensive human studies on the effects of endosulfans and methoxychlor on menarche age. The research that is available shows that exposure to estrogenic chemicals such as endosulfans and methoxychlor has the potential to decrease menarche age due to its promotion of estrogen production. (Ozen, S., Goksen, D., & Darcan, S, 2014) However, human studies are sparse and few in between, making the data available unreliable. More widely available are mice studies on the effects of endosulfans and methoxychlor. Both substances have shown to promote tumors in reproductive organs, increase in infertility, and interferes with the production of sex hormones both in female and male mice. Furthermore, the observed effects on tumor promotion, infertility, and hormone distribution in mice raise serious concerns about the safety of these chemicals, and the potential effects that it could have on human reproductive systems. Endosulfans and methoxychlor are still widely used in many agricultural practices and our gaps in understanding their full impact could be detrimental to anyone who is exposed to them.
The ‘Residual’ Effects
The decrease in menarche age, influenced by exposure to pesticides such as DDT, endosulfans, and methoxychlor, magnifies young girls’ vulnerability early marriages where they are then exposed to gender-based violence, sexual violence, and maternal health risks. In regions that practice early marriages, such as South Asia and Sub-Saharan Africa, the first menstrual cycle is often taken as a sign of marriage readiness. Within in 2 years of starting their cycles, over 70 percent of young girls in these regions are married. On the contrary, for each year that menarche is delayed, marriage is also delayed by 0.74 years. The average menarche age in South Asia and Sub-Saharan Africa is 13.2 years old. As young girls are continuously exposed to dangerous endocrine disrupting chemicals, menarche age continues to decrease over time, and it will result in younger and younger girls being forced into early marriages. It is also worth noting that India, one of the largest South Asian countries, is the world’s largest user of DDT, and there seems to be no declining trend.
In Brazil, the country with the fourth highest number of child brides, a study was conducted by the Brazilian United Health System (BHU) to observe the role of menarche on sexual violence, early marriages, and pregnancies. The mean age of menarche for 201 participants was 12.1 years, with 85 percent of the cohort reporting that they’re sexually active. Within the same cohort, 57 percent of the young girls became pregnant before 15, and there was a strong correlation between age at menarche and age of first pregnancy. Furthermore, the study also asked the cohort about their sexual violence experiences and 51 of the answered that they have experienced some form of sexual violence. More than half of the 51 participants answered that the experienced had taken place when they were 14 and younger. Brazil is not alone in its struggle against early marriages and its associated risks. Studies conducted in Bangladesh, Nepal, Ghana, and Malawi also demonstrated a similar relationship between younger age at menarche, early marriages, pregnancies, and sexual violence.
Early marriages pose a significant threat to young girls, particularly because it exposes them to gender-based and sexual violence at a much earlier age. Those who are married at a young age tend to lack comprehensive sexual education, leaving them ill-equipped to navigate sexual relationships safely. Consequently, young girls are then not able to negotiate and engage in safe sex, increasing their risk to sexually transmitted infections (STIs), unwanted pregnancies, and sexual violence.
Maternal Health Impacts
Adolescent pregnancies are often a reality for young girls in early marriages. Approximately 21 million girls (about the population of New York), aged 15 through 19, become pregnant in low-income countries, and only about 12 millions of them successfully deliver their child. Of the 9 million who did not carry their pregnancy to term, it could have been due to abortion, miscarriages, or pregnancy-related complications that adolescents are more susceptible to. Regardless, adolescent pregnancies are extremely dangerous because the uterine and cervical lining of young girls are less developed, making them more prone to preterm premature rupture of membranes, preterm birth, postpartum hemorrhages, and maternal morbidity. Furthermore, adolescent mothers face a higher risk of eclampsia, puerperal endometritis, and systematic infection during their pregnancies. Beyond the mother, babies carried to term in these pregnancies are also at risk for low-birth weight, preterm birth, and weaker immune systems. This has resulted in high neonatal mortality rates in adolescent pregnancies. With most adolescent pregnancies taking place in low-income countries, these girls already experience limited access to basic neonatal and maternal care, and an even harder time accessing care for the complications mentioned above.
Older and more biologically mature mothers are less prone to these complications but, alarmingly can experience these adverse effects if they have prolonged exposure to pesticides. Specifically, the presence of endosulfans, methoxychlor, and DDT have been identified in older mothers who experienced ectopic birth, lower birth weight, miscarriages, and overall lower neonatal health. (Coall, D. A. & Chisholm, J. S, 2003; Martin, E. J., Brinton, L. A. & Hoover, 1983,) While there are no comprehensive studies published about the role of pesticides and its effects on adolescent pregnancies, we can infer that if pesticides negatively impact stable, healthy pregnancies, it will devastate adolescent pregnancies and mothers.
Conclusion
Today countries in South Asia, Sub-Saharan Africa, and Latin America are still utilizing DDT to control malaria. Widespread use of insecticides such as DDT, endosulfans, and methoxychlor has far-reaching consequences that go beyond disease and pest control. Ingestion and exposure to these chemicals have been linked with disruption of reproductive health such as decrease in menarche age in young girls. This acceleration of menstruation has contributed to a trend of young girls marrying at an increasingly younger age. As a result, these girls are also experiencing adolescent pregnancies at a younger age. Young pregnancies are coupled with dangerous complications, sickly babies, and higher maternal and infant mortality rates.
With climate change harboring the potential to revive vector-borne diseases and countries searching for a large-scale solution will towards insecticides such as DDT, endosulfans, and methoxychlor. Recently, the Public Health Minister in Puerto Rico declared dengue fever an epidemic and malaria cases are returning to the United States, with cases popping up in Texas and Florida. This signals to us that these diseases are reaching regions that have never been affected by it, which in turn means that they are ill-equipped to handle it. As the urge to use ‘fast’ and ‘effective’ control measures to eradicate these diseases persists, we must carefully consider the dangerous societal impacts that insecticide use has on young girls. Safety from vector-borne diseases and efficiency in agriculture should not come at the cost of health and we-ll being of vulnerable populations.
Definitions
Endocrine System: Bodily system composed of organs and glands responsible for hormone production. These hormones are responsible of growth, development, puberty, metabolism, and reproduction.
Endocrine Disruptor Chemicals (EDCs): Any chemical that can bind onto hormones that disrupts cell signaling pathways. This directly affects hormone synthesis and can alter rates of growth and development.
Estrogen: A sex hormone that is commonly found in those who are assigned female at birth. This hormone is often responsible for regulating fertility, menstrual cycles, and homeostasis of reproductive organs.
Estrogenic Chemicals: Chemicals able to mimic or antagonize the activity of estrogen.
Dichlorodiphenyltrichloroethane (DDT): An insecticide that is commonly use to keep insects off of crops. DDT can be ingested if someone consumes food that has been previously treated with DDT. It is also commonly used as a malaria vector control in malaria epidemic countries.
Methoxychlor: Another insecticide that is also commonly used in agriculture. Similar to DDT, but acts quicker and does not reside in the fatty tissues of animals like DDT does.
Menarche: The age at which someone first experiences the signs of puberty. Often the start of the menstrual cycle and development of breasts.
Endosulfans: An insecticide widely used with similar abilities to DDT and methoxychlor. Can also be ingested if food was treated with endosulfans.
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