(Beyond Pesticides, August 14, 2023) Marijuana regulators in the state of Washington issued administrative holds on 18 licenses due to pesticide-contaminated marijuana, forcing producers and processors to cease operations until now. This shutdown of legal marijuana businesses serves as a window into a broader historical backdrop of pesticide issues within the marijuana industry. Within Washington, pesticide concerns have been growing since a study in 2018 of legal marijuana farms in the state had 84.6% (of 26 samples) with significant quantities of pesticides including insecticides, fungicides, miticides, and herbicides. Last year, a national study identified a list of contaminants in 36 states and the District of Columbia and found 551 pesticides within cannabis products. For over a decade, Beyond Pesticides has sounded the alarm about the highly-concentrated levels of pesticides in marijuana products, calling on state officials to require organic marijuana, especially in the context of medical marijuana. The absence of federal regulations for pesticides in cannabis production has raised significant concerns about exposure risks for recreational and medicinal use, exposure risks to workers, and potential environmental contamination impacting wildlife. Since marijuana is classified as a Schedule 1 narcotic under the Controlled Substances Act, the EPA does not regulate pesticides in […]

(Beyond Pesticides, March 28, 2023) High concentrations of fully intact, never broken down DDT remain on the California seafloor decades after it was dumped off its southern coast in the middle of the 20th century. “We still see original DDT on the seafloor from 50, 60, 70 years ago, which tells us that it’s not breaking down the way that [we] once thought it should,” University of California Santa Barbara scientist David Valentine, PhD, told the Los Angeles Times. “And what we’re seeing now is that there is DDT that has ended up all over the place, not just within this tight little circle on a map that we referred to as Dumpsite Two.” These findings underscore the enormity of legal and regulatory decisions to approve production of hazardous chemicals. While many may believe the legacy of DDT ended with its ban in the early 1970s, the California findings raise a deeper problem not only with U.S. chemical policy, but also the response from well-meaning environmental nonprofits that continues to play out to this day. As many in the environmental community invest tremendous resources in seeking to ban problematic pesticides or chemicals of the day after the contamination has occurred […]

(Beyond Pesticides, December 6, 2022) Persistent organic pollutants (POPs)—including banned pesticides—present a health risk to humpback whales (Megaptera novaeangliae), according to a study published in Environmental Pollution. Regarding female humpback whales, levels of POPs in blubber are higher in juveniles and subadults than in adults, primarily from the transference of contaminants from the mother to her calf.  Organochlorine compounds (OCs), such as organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs), are well-known persistent organic pollutants. The international Stockholm Convention treaty (signed by 152 countries, but not the U.S.) banned these primary pollutants of concern (UNEP, 2009) in 2001 (taking effect in 2004) because of their persistence, toxicity, and adverse effects on environmental and biological health. These pollutants have a global distribution, with evaporation and precipitation facilitating long-range atmospheric transport, deposition, and bioaccumulation of hazardous chemicals in the environment. However, these chemicals can remain in the environment for decades and interact with various current-use pesticides, including organophosphates, neonicotinoids, and pyrethroids. Although various studies demonstrate the volatile, toxic nature of POPs, much less research evaluates the impact POPs have on maternal offloading or transfer of contaminates to offspring and respective health consequences. The globe is currently going through the Holocene Extinction, Earth’s 6th mass extinction, with one […]

(Beyond Pesticides, November 7, 2022) The Maine Congressional delegation — Senators Collins (R) and Angus King (I), and Representatives Chellie Pingree (D) and Jared Golden (D), along with New Hampshire Senator Jeanne Shaheen (D) — have  introduced a bipartisan bill — the Relief for Farmers Hit with PFAS Act — to help farmers who have been adversely affected by the scourge of PFAS (perfluoroalkyl and polyfluoroalkyl substances) chemicals. The bills are the identical S. 5070 and H.R. 9186, both titled “Relief for Farmers Hit with PFAS Act.” Tell your U.S. Senators and Representative to cosponsor the Relief for Farmers Hit with PFAS Act. If they are already cosponsors, thank them. Tell EPA to stop the spread of legacy chemicals. PFAS chemicals, also known as “forever chemicals,” are legacy contaminants or those whose historical use, including many decades ago in some instances, has led to their toxic persistence in the environment and in organisms. PFAS chemicals are not the only legacy contaminants. Others include wood preservatives, DDT, dioxins, and the termiticide chlordane. Unfortunately, some of these continue to be added to the environment, sometimes inadvertently, but also intentionally, particularly through pesticide use. As indicated by the title of these bills, farmers […]

(Beyond Pesticides, August 24, 2022) New research is helping the medical community understand the mechanism through which exposure to the banned insecticide DDT increases risk of Alzheimer’s disease. Published in the journal Environmental Health Perspectives, a team of researchers from Florida International University and Rutgers used multiple models to demonstrate the effects of DDT on the production of toxic proteins in the brain. The constant stream of new health risks regarding a chemical banned decades ago underlines the importance of a precautionary approach to pesticide regulation, particularly as red flags are already being raised about the connection between widely used weed killers like glyphosate and neurodegenerative diseases like Alzheimer’s. “The vast majority of research on the disease has been on genetics — and genetics are very important — but the genes that actually cause the disease are very rare,” says study coauthor Jason Richardson, PhD of Florida International University. “Environmental risk factors like exposure to DDT are modifiable. So, if we understand how DDT affects the brain, then perhaps we could target those mechanisms and help the people who have been highly exposed.” Previous research from Dr. Richardson found that DDT exposure increased risk of Alzheimer’s by four times. Scientists […]

(Beyond Pesticides, June 10, 2021) Exposure to toxic chemicals decreases egg count and increases infertility risk among women, according to a study published in Environment International. Since 2014, U.S. fertility rates have been decreasing, with many attributing the decline to older age pregnancies. However, several findings demonstrate that exposure to environmental pollutants, like persistent organic pollutants (POPs) from the industrial and agriculture industry, contributes to a decline in fertility rates. Scientists and health officials already associate exposure to POPs, like pesticides, with adverse impacts on male fertility, including reduced sperm count, quality, and abnormal sperm development. Therefore, it is essential to understand how exposure to toxic chemicals in the environment affects reproductive success, especially among women who can transfer contaminants to the fetus via the umbilical cord. The researchers note that these findings should urge government and health officials to reexamine chemical safety concerning reproductive health, and “strongly encourage [them] to study mechanisms behind POP-associated infertility in women in more detail.” Researchers examined ovarian egg reserve size in pregnant women directly by examining the density of follicles and immature eggs in ovarian tissue and indirectly via serum anti-Müllerian hormone (AMH). Using AMH serum samples, researchers assessed concentration levels of 31 POPs: nine organochlorine pesticides (OCPs), ten polychlorinated […]

(Beyond Pesticides, April 22, 2021) Past maternal exposure to the pesticide dichlorodiphenyltrichloroethane (DDT) during pregnancy can increase the risk of breast cancer and cardiometabolic disorders (e.g., heart disease, obesity, diabetes) up to three successive generations, according to a new study published in Cancer Epidemiology, Biomarkers & Prevention. Although previous studies highlight early life or in utero exposure to DDT increasing breast cancer risk later in life, this study is the first to note generational effects on grandchildren’s health. DDT continues to adversely affect the health of the U.S. population, nearly 50 years after its ban. However, this ban is not global, as many countries still use or manufacture the chemical compound. Furthermore, residues of DDT metabolite, DDE, continue to readily contaminate food and water worldwide. Therefore, studies like these highlight the need to investigate how first-generation pesticide exposure can impact future generational health in order to prevent adverse health outcomes, especially during sensitive developmental periods (i.e., in utero, infancy/childhood). The study researchers note, “Discovery of actionable biomarkers of response to ancestral environmental exposures in young women may provide opportunities for breast cancer prevention.” To assess the association between multi-generational health risks and chemical exposure, researchers used the Public Health Institute’s Child […]

(Beyond Pesticides, February 25, 2021) A University of Michigan study finds a link between elevated rates of breast cancer incidents and chemical exposure from pesticides among African American women. Breast cancer is the most common cancer among women, causing the second most cancer-related deaths in the United States. However, breast cancer outcomes differ significantly among women of various races/ethnicities, with African American women being 40 percent more likely to die from breast cancer than women of any other race. Furthermore, incidences of triple-negative breast cancer (TNBC)—an aggressive breast cancer subtype lacking remediation—is approximately three-fold higher in non-Hispanic Black women (NHBW) compared to non-Hispanic White women (NHWW). Although past studies suggest genetic and environmental factors interact to produce these differences in breast cancer outcomes, genetic factors only play a minor role while disparities (differences) in external factors (i.e., chemical exposure) may play a more notable role. This study highlights the significance of understanding how chemical exposure drives disease outcomes and increases disease risk, especially for more virulent diseases that disproportionately (unequally) impact specific communities. Prior research infers differences in chemical exposure may explain racial disparities for several illnesses, and growing evidence suggests common chemical exposure patterns influence the risk of breast cancer. […]

(Beyond Pesticides, August 20, 2020) Persistent organic pollutants (POPs), including banned and current-use pesticides are present in snow and ice on top of Arctic glaciers, according to the study, “Atmospheric Deposition of Organochlorine Pesticides and Industrial Compounds to Seasonal Surface Snow at Four Glacier Sites on Svalbard, 2013–2014,” published in Environmental Science & Technology. Past research finds that air contaminated with these environmentally bioaccumulative, toxic chemicals drift toward the poles, becoming entrapped in ice under the accumulating snowfall. As the global climate continues to rise and the climate crisis worsens, studies like this become significant, as glaciers encapsulating these toxic chemicals are melting. Upon melting, some chemicals can volatize back into the atmosphere releasing toxicants into air and aquatic systems, with the ensuing consequences. Although this research demonstrates that specific computer programs can track the trajectory of chemically contaminated air parcels with practical precision, it falls to global leaders to curtail the continued manufacturing of these chemical pollutants. [For related pieces, see Silent Snow: The unimaginable impact of toxic chemical use and DDT in Glacial Melt Puts Alaskan Communities at Risk.] Countless scientists consider Arctic environments to be “pristine,” void of direct chemical inputs from pesticides and other POPs. However, the Arctic has become a sink for […]

(Beyond Pesticides, July 9, 2020) Conventional U.S. milk contains growth hormones, antibiotics, and low to elevated levels of pesticides not found in organic milk, according to a study published in the journal of Public Health Nutrition by Emory University researchers. Milk can bioaccumulate certain organic pollutants, making it a valuable medium to assess what chemical we might be ingesting daily. With milk being one of the most consumed beverages in the U.S., in addition to its use in other popular drinks (i.e., coffee and tea), this study discloses widespread contamination and highlights the need for improved regulation. Researchers in the study note, “To our knowledge, the present study is the first study to compare levels of pesticide in the U.S. milk supply by production method (conventional vs. organic). It is also the first in a decade to measure antibiotic and hormone levels and compare them by milk production type.”  The market for conventional milk, produced in chemical-intensive agriculture, is declining, but the demand for organic milk is increasing due to concerns over chemical contamination in consumer products from pesticides and other toxic chemicals. Although the U.S. Environmental Protection Agency (EPA) sets limits for pesticide residues in food products, the agency […]

(Beyond Pesticides, July 8, 2020) Efforts to control the transmission of malaria are encountering a big, though predictable, problem: the mosquitoes that transmit malaria are developing resistance to at least five of the insecticides that have been central to limiting transmission of the disease. A study released in late June reveals a dramatic increase in resistance to pyrethroid insecticides and DDT across sub-Saharan Africa. This signals the failure of a mainstay chemical approach to the spread of malarial mosquitoes; this same problem — resistance — is happening with chemical management of agricultural pests and weeds, and with antibiotics to treat human bacterial infections. This study underscores a point Beyond Pesticides has made repeatedly: resistance to pesticides (whether insecticides, herbicides, biocides, fungicides, or medical antibiotics) is nearly inevitable. The solution to containing the spread of malaria lies not in the use of more and different chemicals, but in nontoxic approaches that respect nature and ecological balance. Malaria is a sometimes deadly disease caused by female Anopheles mosquitoes infected with any of four varieties of the Plasmodium parasite. The disease kills roughly 400,000 people annually, with half that mortality in sub-Saharan Africa. The U.S. sees approximately 2,000 cases of malaria annually, primarily in […]

(Beyond Pesticides, May 14, 2020) Four banned organochlorine pesticides (OCP) are present in over 60% of a cohort of reproductive-age, black women in Detroit, according to a study published in Environmental Research by Boston University School of Public Health (BUSPH). OCPs are lipophilic (fat combining/dissolving), environmentally steadfast chemicals linked to harmful health effects. This study stresses the importance of monitoring pesticide accumulation, particularly regarding environmentally persistent chemicals and their metabolization via indirect exposure routes. Lead author Olivia Orta, Ph.D., a postdoctoral research associate in the Department of Epidemiology at BUSPH, highlights the significance of water monitoring—especially in light of historically disproportionately high hazards for people of color (e.g., Flint, Michigan)—and testing sources prone to OCP contamination. She remarks, “The sources that we identified as potential OCP correlates should be tested for pesticide contamination,[…] especially drinking water.” Environmental contaminants, like organochlorine pesticides (OCP), can persist in the environment decades after use stops, as OCPs have greater chemical stability and gradual attenuation. Minority populations are at higher exposure risk of environmental contaminants (i.e., pesticide) exposure that can catalyze adverse health and birth effects, especially in metropolitan areas. Although black women endure higher body burdens than other U.S. populations, there remains a lack of research surrounding the association. Boston University researchers enrolled […]

(Beyond Pesticides, May 13, 2020) A pilot study at New York University (NYU) provides evidence of a direct relationship between increased risk for celiac disease (adverse immune response to eating gluten) and exposure to endocrine-disrupting chemicals, including DDE – a metabolite of the infamous, bird-killing pesticide DDT. Researchers at NYU set out to elucidate the connection between the autoimmune disease and persistent organic pollutants (POPs), also known as “forever chemicals” or “legacy chemicals” due to their persistence in nature and the human body. The new research, published in Environmental Science, highlights higher odds for celiac disease among participants with elevated POPs exposure and differing results among male and female participants. Considering the complexity of these initial results, researcher Leonardo Trasande, Ph.D. says, “It’s not as if these chemicals were designed with the human body in mind; These chemicals were designed with materials in mind.” [See video overview here] Celiac disease produces an immune-mediated inflammatory response to the consumption of gluten, a protein found in wheat, rye, and barley. Risk for celiac disease has long been associated with genetic factors, but increased prevalence of the disease inspired further research. Considering previous studies on the deleterious impact of POPs on the immune […]

(Beyond Pesticides, December 17, 2019) South Asian immigrants to the U.S. may be at increased risk of diabetes due to prior exposure to high levels of DDT, research published by the University of California Davis earlier this month indicates. The study highlights a blind spot for health care in the U.S., researchers say. “Our findings evoke a new interpretation of Rachel Carson’s famous book Silent Spring, in that the high DDT exposures of South Asian immigrants in the U.S. currently fall on deaf ears in the U.S.,” said lead author Michele La Merrill, PhD an associate professor in the UC Davis Department of Environmental Toxicology. “Although DDT remains in use in other nations and migration globalizes these exposures, people in the U.S. often mistakenly regard DDT exposure as no longer relevant to our society due to its ban in this country nearly 50 years ago.” When compared to other race and ethnic groups, South Asian immigrants (individuals from India, Pakistan, Bangladesh, Nepal, Sri Lanka, and Bhutan), are at greater risk of developing diabetes, even when adjusting for potential confounders such as age and obesity. Authors of the study hypothesized that this was a result of past exposure to high levels […]

(Beyond Pesticides, February 20, 2019) Women exposed to DDT during ‘early windows of susceptibility’ in their childhood are at increased risk of developing breast cancer, according to new research published in the Journal of the National Cancer Institute. Nearly 75 years after the chemical was first used in the U.S., and 50 years after its ban, DDT is continuing to adversely affect the health of Americans. The data brings needed attention to the dangers of early-life pesticide exposure, and underlines the need to take a precautionary approach to the introduction of biocides in our environment so that future generations do not suffer from the same mistakes of the past. “What we have learned is that timing really matters. We know that if harmful exposures occur at times when breast tissue is rapidly changing, such as during puberty, they impact breast development in ways that can later result in cancer,” said lead author Barbara A. Cohn, PhD, of the Public Health Institute’s (PHI) Child Health and Development Studies. “The research published today suggests that DDT affects breast cancer as an endocrine disruptor, that the period of time between first exposure and cancer risk seems to be around 40 years–and that other […]

(Beyond Pesticides, January, 23, 2019) Individuals that have been acutely poisoned by pesticides at some time in their life may be more likely to lose their sense of smell, according to a recent study published in Environmental Health Perspectives.  Researchers focused on the effect of high pesticide exposure events (HPEE), such as a pesticide spill or other incident, on a farmers’ ability to smell later in life. This is the first study to indicate pesticide exposure may result in olfactory impairment. Farmers from Iowa and North Carolina enrolled in an ongoing U.S. Agricultural Health Study have been asked about their pesticide use roughly every 5 to 6 years since 1993. In the most recent survey, taken from 2013-2015, farmers were asked additional questions about HPEE in their lifetime and whether they had a significantly decreased or impaired sense of smell. “Studying farmers gives us more reliable data on pesticide exposures than if we had studied the general population,” says Honglei Chen, MD, PhD, lead author and professor of epidemiology at Michigan State University in a press release. “Because they use pesticides more and it’s part of their job, they’re more likely to remember what pesticides they used and in cases […]

(Beyond Pesticides, December 11, 2018) Meltwater and runoff from Alaskan glaciers contain detectable levels of organochlorine pesticides that bioconcentrate in fish and put individuals at risk, according to a new study from researchers at the University of Maine (UMaine). DDT, lindane, and other organochlorines have been detected throughout the world, even in natural areas thought to be untouched, and pristine. As UMaine scientists show, the atmospheric transport and ubiquitous deposition of these pesticides continues to pose risks to U.S. residents long after regulations banned their use. Although most of the highly toxic class of organochlorine pesticides like DDT were banned in the early 1970s, some chemicals retained certain uses. Lindane, for example, had its pest management uses phased out gradually until 2007, but is still allowed today as a scabies and lice shampoo. While use of these pesticides has declined in the U.S., much of the developing world, including many Asian countries, such as China, India, and North Korea, still report use. This results in atmospheric transport of the pesticides, and relevant to the UMaine research, increases the likelihood that the chemicals will eventually be deposited onto Alaskan glaciers through snow or rain. The UMaine research team investigated the amount of […]

(Beyond Pesticides, November 30, 2018) A study published this month in Science of the Total Environment reveals numerous pesticide residues persisting in soil, harming the viability of agricultural lands and increasing risk of off-site contamination. Funded by the Horizon 2020 programme of the European Commission, researchers from the European Diverfarming project at the University of Wageningen in the Netherlands suggest nations urgently reevaluate conventional land use and inputs including water, energy, fertilizers, machinery and pesticides. Researchers decrying the lack of soil protection policies endeavored to determine which pesticides had the highest soil persistence and toxicity to non-target species. Three hundred seventeen surface soil samples were analyzed from 11 European countries. Selected countries were those with the largest amounts of active agricultural land, characterizing six distinct cropping systems. Sampled soils purposefully represented different soil properties and were taken from crops with the highest pesticide use per hectare. Samples were then analyzed for the concentration of 76 pesticide residues. These 76 pesticides were selected as being most often applied on conventional crops. Eighty-three percent of samples contained varying degrees of pesticide residues, with 25 percent showing one pesticide residue and 58 percent showing mixtures of two or more. Only 17 percent of […]

(Beyond Pesticides, August 22, 2018) Mothers with high levels of DDT’s major metabolite, DDE, are more likely to have their children diagnosed with autism, according to a study published in The American Journal of Psychiatry this month. Though this study links autism to long-banned DDT, it raises significant concerns about legacy contamination from this chemical, which remains ubiquitous in the environment and in human bodies. With an increasing number of studies linking autism and other developmental disabilities to pesticides, the need to transition to safer, organic methods of farming is now more important than ever before. The study, Association of Maternal Insecticide Levels With Autism in Offspring From a National Birth Cohort, measured maternal serum levels of Finish women during early pregnancy whose children were born between 1987 and 2005. Specimens were analyzed for DDE as well as PCB contamination. Mothers with DDE at the highest 75% threshold reportedly had a 132% (1.32x odds ratio) increased risk of having a children diagnosed with autism after adjusting for confounders such as age and history of psychiatric disorders. Moms above the 75th percentile had their chances of a child’s autism diagnosis increase by 221% (2.21x odds ratio). The study found no connection […]

(Beyond Pesticides, May 31, 2018) Deforestation in tropical regions helps spread malaria, concludes a recent research study of the Amazon Rainforest. Published in Nature’s open-access journal, Scientific Reports, the study details researchers’ work, from 2009–2015, comparing patterns of deforestation to rates of malaria in nine states in the Brazilian rainforest. Investigators found that the highest malaria incidence concentrated in impacted patches of forest — areas deforested or otherwise degraded from an unmanaged or more-natural state. These medium-sized patches (from .1 to 5 sq. km. in size) seem to be the “sweet spots” at which wood extraction activity (logging, charcoal production, et al.) correlate most strongly with malarial infection rates. The researchers suggest that the finding is perhaps related to the habitat preferences of the primary malaria vector in the region, Anopheles (Nyssorhynchus) darlingi, which breed most happily in shady, watery, edges of forest habitat. Sixty of the 380 mosquitoes in the genus Anopheles can transmit the malaria parasites. Deforestation fragments the forest landscape, creating more forest “edges,” which means more places for mosquitoes to breed. This fragmentation may also help malaria-carrying mosquitoes spread to other areas as adults: “The new [fragmented] landscape delineated by the pattern of deforestation and soil occupation may favor […]

(Beyond Pesticides, June 7, 2017) Fruit flies that developed a genetic resistance to the insecticide DDT have lower success at mating than those without similar changes, according to a study published last month in the journal Behavior Genetics. The results were surprising to researchers, given that the resistance developed through changes to a single allele (a variation of a single gene). “It is amazing that even if all the genes are exactly the same, having this one gene expressed at a higher level has all these effects,” said Professor Nina Wedell, PhD, of the Centre for Ecology and Conservation on Exeter’s Penryn Campus in Cornwall, UK to Phys.org. The study raises possible concerns about the effect of pesticide exposure to non-target (not the focus of pesticide use) insects that are integral to a healthy ecology and food web. In conducting their investigation, researchers studied the biological fitness costs associated with the development of an insecticide resistance gene. After scientists bred resistant flies in the lab, they set up a series of “competitive mating trials,” comparing both courtship behavior and the impact of size on male fruit flies’ mating success. In general, resistant males were found to be smaller than flies that […]

(Beyond Pesticides, August 24, 2016) Researchers at Drexel University report that higher levels of some organochlorine compounds during pregnancy are associated with autism spectrum disorder (ASD) and intellectual disability (ID). The organochlorine compounds under study have long been banned in the U.S., and include pesticides like DDT, underscoring how pervasive and persistent these chemicals are, and their continued impact on human health. The research is reported in the study  Polychlorinated Biphenyl and Organochlorine Pesticide Concentrations in Maternal Mid-Pregnancy Serum Sam ples: Association with Autism Spectrum Disorder and Intellectual Disability,  which examines whether prenatal exposure to polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) influences offspring risk of ASD and intellectual disability without autism (ID). According to the research, children born after being exposed to the highest levels of organochlorines during their mother’s pregnancy are roughly 80 percent more likely to be diagnosed with autism when compared to individuals with the very lowest levels of these chemicals. The team looked at a population sample of 1,144 children born in Southern California between 2000 and 2003. Data was accrued from mothers who had enrolled in California’s Expanded Alphafetoprotein Prenatal Screening Program, which is dedicated to detecting birth defects during pregnancy. Participants’ children were […]

(Beyond Pesticides, November 10, 2015) Exposure to organochlorine chemicals, such as DDE and PCBs, is linked to increased rates of sperm abnormalities that may lead to fertility problems, according to a new study published in the journal Environmental Health Perspectives. This is the latest study in a long line of research implicating endocrine (hormone)-disrupting chemicals in reproductive diseases. Researchers investigated this issue by observing the blood serum and sperm quality of 90 men, aged 22-44, participating in health studies in the Faroe Islands, an archipelago under  Denmark’s control that is  located between Iceland, the UK and Norway. Faroe islanders consume a high seafood diet that often consists of pilot whale, integral historically as a  food source for the Faroese people. However, this practice exposes the Faroese to higher than average levels of environmental contaminants. For the study, data on umbilical cord blood and blood serum at age 14 was available for 40 of the participants, allowing a researchers to measure lifetime impacts. Faroese participants were screened for sperm aneuploidy, a condition which usually involves an abnormal number of X or Y chromosomes in sperm, and is suspected as contributing to congenital abnormalities and up to 50% of early pregnancy losses. […]