A new analysis of more than two dozen studies found toxic chemicals in 90 percent of household dust samples taken from 14 states. 
 
 Household dust does more than collect in corners and on bookshelves full of novels you haven’t gotten around to reading. A new study shows it can expose people to a wide range of potentially toxic chemicals. 
 
 In what the authors are calling the first study of its kind – a meta-analysis of more than two dozen previous studies on chemicals in dust – they report that 90 percent of dust samples taken from houses in 14 states contain harmful chemicals, including one that’s known to cause cancer. 
 
 “Most studies only measure a few chemicals so it makes it hard to understand typical exposures in homes and work places,” said the study’s lead author Ami Zota, an assistant professor of environment and occupational health at Milken Institute School of Public Health at the George Washington University, in Washington, D.C. 
 
 The researchers – who also came from Harvard University, the University of California-San Francisco, Silent Spring Institute and the Natural Resources Defense Council – analyzed data from 26 peer-reviewed papers and one unpublished set of data. The collected data included 45 chemicals from five chemical classes. 
 
 “We wanted to be able to draw more solid conclusions about concentrations of indoor chemicals in the U.S. by pooling data across all of these studies,” Zota explained. 
 
 The chemicals studied come from all sorts of common consumer goods, including furniture, personal hygiene products, flooring, baby products, cleaning supplies, fast food and food packaging. Zota said the chemicals are released into the air and then seep into dust that settles on furniture and floors. People can inhale or ingest small particles of dust or even absorb them through the skin. 
 
 To analyze the previous studies, the scientists parsed the information from three different angles: the level of chemical concentration in dust, how much might be getting into our bodies, and how hazardous the chemicals are. 
 
 “No matter which way we looked at it, there were some chemicals that stood out,” co-author Veena Singla, a staff scientist with the Natural Resources Defense Council, told CBS News. The non-profit group helped to fund the study. 
 
 Ten harmful chemicals were found in 90 percent of the dust samples tested. Phthalates, used in toys and vinyl flooring, among other products, occurred in the highest concentrations. 
 
 They were followed by phenols, often used in cleaning products. Then came flame retardants, fragrances and perflouroalkyl substances, which are used in carpets, textiles, and leather to make them water-, oil- and stain-repellent and to create grease-proof and waterproof coatings for products such as paper plates and food packaging. 
 
 “Phthalates are linked to multiple health hazards, including reproductive,” Signla said. “And some flame retardants are linked to cancer.” 
 
 The authors of the study, published in the journal Environmental Science & Technology, were especially concerned about exposure to children, especially very young children who crawl around on the floor and put their hands in their mouths. 
 
 Chemicals of top concern: 
 
 TCEP - A flame retardant added to couches, baby products, electronics and other products 
 
 DEP, DEHP, BBzP and DnBP – These chemicals, different varieties of phthalates, are found in an array of drugstore items like those listed above, as well as some highly processed foods and fast food. Phthalates are also linked to IQ and respiratory problems in children. 
 
 PFOA and PFOS - These chemicals​ are found in cellphones, pizza boxes and many non-stick, waterproof and stain-resistant products. They’ve been linked to developmental problems​ and issues with the immune, digestive, and endocrine systems. 
 
 These may be worrisome when they accumulate in household dust, the researchers say. 
 
 “Indoor dust is a reservoir for commercial consumer product chemicals and many of these chemicals have known and suspected health effects,” Zota said. 
 
 “This is the first study where we can get a more comprehensive picture of chemical contamination in the home,” Singla added. “Previous studies were like looking at the individual dots in an Impressionist painting. Putting this data altogether, we could see what the bigger picture is and it’s really kind of scary.” 
 
 The authors said small amounts can add up over time and potentially impact health. 
 
 “On the one hand, I wasn’t that surprised, and on the other hand I was surprised to see just how bad it was. I definitely expected to see a number of toxic chemicals when we put the data together, but just the extent of it did surprise me,” Singla said. 
 
 The study doesn’t answer all of the researchers’ questions, however. There are still big gaps in knowledge about many chemicals. 
 
 “We know so little about fragrance chemicals. They’re a prime example of the problem of not having information on what’s in our products because companies claim trade secrets,” Singla said. 
 
 Safer alternatives need to be developed, said Zota. 
 
 “One of our objectives with this – because there are so many consumer product chemicals being used currently in commerce with incomplete health and safety information – was to conduct this analysis with the objective of helping researchers as well as decision-makers to set priorities. Which chemicals to prioritize, in terms of conducting future health assessments. As well as which chemicals to actively develop safer alternatives for,” Zota said. 
 
 Individuals can take a number of steps to improve safety, Singla said. 
 
 In your own home, day-to-day, washing your hands​​ with plain soap and water can cut down on the amount of dust you come into contact with. Vacuuming with a HEPA-filter, wet mopping and dusting with a damp cloth can reduce exposure to dust, as well. 
 
 In the longer term, she said, “There are regulatory and legislative solutions. It does make a difference when people tell their government agencies that this matters to them and they’re concerned.” Singla also noted that the Natural Resources Defense Council has a petition for the FDA to ban phthalates from food, which supporters can sign online. 
 
 “We think our homes are safe havens, but what we found is the surprising reality that our homes are being polluted by the products we have every day. Our choices about what we buy and the policies we support can make a real difference,” Singla said. ||||| TIME Health For more, visit TIME Health 
 
 Ten chemicals suspected or known to harm human health are present in more than 90% of household dust samples, according to a new study. 
 
 The research, published in the journal Environmental Science and Technology, adds to a growing body of evidence showing the dangers posed by exposure to a slew of chemicals people in developed countries encounter on a day-to-day basis. The chemicals come from a variety of household goods that includes toys, cosmetics, furniture, cookware and cleaning products. 
 
 A class of chemicals known as phthalates — a group that includes DEP, DEHP, DNBP and DIBP — are present in the highest concentrations, according to the research. That class of chemicals is also thought to be among the most harmful. Exposure to phthalates may interrupt the endocrine system, leading to a decrease in IQ and respiratory problems, among other problems, health researchers say. 
 
 Read More: You Asked: Can My Couch Give Me Cancer? 
 
 Highly fluorinated chemicals (HFCs), another class of chemicals common in household dust, has been linked to kidney and testicular cancer. The compound is found in everything from cell phones to pizza boxes, according to the study. 
 
 Researchers behind the study, which evaluated datasets from more than 25 prior studies, called for manufacturers to replace the chemicals in their products with safe alternatives, but, voluntary participation aside, the path to force companies to replace chemicals remains difficult. For decades, chemicals in this country have been eligible for use without tests to confirm their safety. 
 
 An overhaul to the Toxic Substances Control Act passed earlier this year will require the Environmental Protection Agency (EPA) to sign off on new chemicals before they enter the open market, but still thousands of chemicals on the market today remain untested. The Environmental Working Group, an environmental nonprofit, estimates that 1,000 of those chemicals warrant further scrutiny, but the EPA does not have the staff — or the time — to invest in such an effort. Instead, the EPA has selected a much smaller list of priority chemicals to evaluate first. 
 
 The research comes as scientists increasingly understand that exposure even to very low levels of these toxic substances can damage human health. And, while exposure on any given day may be small, each exposure adds up. ||||| The dust in our homes and the air we breathe harbor a complex stew of chemicals. Some, like oxygen, sustain life. Others are pollution stemming from things like car exhaust or from tiny scraps of household products. A pair of new studies adds a level of much-needed detail about exactly how widespread such toxic exposures can be. 
 
 A new analysis, published Wednesday in Environmental Science & Technology, reaffirmed that consumer product chemicals including phthalates, phenols and flame retardants are ubiquitous components of household dust. These substances are present at such high levels that researchers say it is likely we are inhaling and accidentally eating small amounts of these chemicals every day, although we don't yet know whether this level of exposure is enough to do harm. 
 
 Such exposures occur after the chemicals flake off of products including building materials, electrical cords or perfume, says senior author Ami Zota, a professor of environmental and occupational health at The George Washington University. To better understand the scale of such exposures she and her colleagues collected the findings of 26 peer-reviewed studies and one unpublished data set on indoor dust samples from 14 states. The samples came from urban, suburban and rural settings, and included houses as well as other locations like schools and workplaces. The 10 most common chemicals in the study were found in over 90 percent of samples, which suggests they come from items present in most people's households and communities. 
 
 The most abundant chemical in the analysis was di(2-ethylhexyl) phthalate (DEHP), a phthalate that is used in flexible plastics as well as in cosmetics and personal care products. In mice and rats, ingesting high doses of DEHP interferes with the development of the male reproductive system and is linked to liver cancer. When the investigators ranked the chemicals according to how much preschool-aged children were likely to ingest, the flame retardant tris(2-chloroethyl) phosphate (TCEP) came out on top. TCEP has been linked to cancer and brain damage in mice, but like many of these household chemicals we don't know whether it might be dangerous to humans. 
 
 An important limitation of the study is that it only looked at the types and amounts of chemicals present in dust—not the health of people who spent time in places where the dust was collected. For many of the chemicals, we don't yet know what amount should be considered hazardous for long-term exposure, Zota says. And we don't know whether some of the chemicals might be more harmful in combination than they are individually. 
 
 Tracey Woodruff, who was not involved with the new analysis, calls the work a “great contribution” to the study of chemicals in household dust. She's the director of the Program on Reproductive Health and the Environment at the University of California, San Francisco, and she was previously a senior scientist and policy analyst at the U.S. Environmental Protection Agency. “The dust is out there. We know the chemicals are in the dust,” she says. “Now we have a better picture of what that looks like and also what we’re going to be ingesting, which is really important for thinking about risks.” 
 
 In the Air 
 
 A second study raises new questions about air exposures we might encounter outside the home. Work published in Proceedings of the National Academy of Sciences on September 6 suggests magnetite nanoparticles, typically found in the air, may travel farther than previously believed throughout the human body and ultimately lodge in human brain tissue. Such particles from air pollution have long been linked to respiratory disease, Woodruff says, but the link to brain health is “newly being appreciated.” 
 
 The researchers examined 37 samples of brain tissue from people who had lived in Manchester, England, and in Mexico City. They used a sensitive magnet to confirm that magnetic particles were present in the brains and then looked for the particles under a transmission electron microscope. Although our bodies produce a small amount of magnetite—a mineral made of iron and oxygen—specific characteristics of the magnetite particles researchers found in the brain samples suggest these substances did not come from the body. Typically, such particles appear crystal-shaped under an electron microscopic. Yet Barbara Maher, who studies magnetic minerals that occur in the environment at Lancaster University, and her team found that most of the samples from the brain were actually smooth and round. 
 
 That shape, along with other clues like particle size and the presence of other metals, suggests they were produced at high temperatures—likely in the engines of vehicles. “In essence they are molten droplets,” Maher says. ”If they cool quickly enough, they keep that spherical shape.” 
 
 The particles are small enough that they can enter the brain through the olfactory nerve via the nose. Nobody has yet proved that magnetite contributes to Alzheimer's or any other disease—magnetite has been detected previously in the brains of some Alzheimer’s patients—but the mineral is known to create free radicals that can damage cells. As a result, Maher believes it is “highly improbable” that the particles' presence in the brain is harmless. 
 
 “The levels of magnetite they found in the brain are much higher than have been found in other studies,” says Jon Dobson, who studies magnetic nanoparticles in biomedicine at the University of Florida and was not involved in the study. There is a chance the high levels were from accidental contamination in the lab, in spite of the researchers' careful steps to avoid it, he says. But if the high levels are simply due to the patients being exposed to high levels of pollution, future studies involving a control group from less polluted areas could confirm the findings. 
 
 Removing nanoparticles and consumer product chemicals from our environment is a big job that would require major policy changes, for example banning the most toxic chemical from products. In the meantime, though, both Zota and Woodruff note that washing your hands before you eat can significantly reduce your accidental intake of the chemicals found in dust. They also recommend vacuuming with a high-efficiency particulate air (HEPA) filter, which is designed to remove very fine particles. 
 
 Maher points out that walking farther away from busy roads may also help to reduce how much exhaust you breathe in. Even walking on the downhill side of the road, she says, rather than the uphill side where drivers burn more fuel as they accelerate, may make a difference. “Any distance that you can put between you and the source of the particles is a good thing.” ||||| (CNN) When was the last time you dusted your house? 
 
 Your answer could reveal a lot about your home habits, but the findings of a new study might have everyone upping their game -- and potentially keeping wet wipes and hand sanitizer nearby at all times. 
 
 Researchers at George Washington University say 45 toxic chemicals are found commonly in your house dust, with 10 of them lurking in 90% of homes across the country. 
 
 "We wanted to identify which chemicals were present at the highest exposure in homes," said Dr. Ami Zota , an assistant professor of environmental occupational health who led the study. "Some chemicals were in virtually every dust sample." 
 
 To reveal which potential toxins we're being exposed to in the comfort of our own homes, Zota's team analyzed all studies that have sampled indoor environments in the United States since 2000. They looked for the presence of potentially toxic chemicals and divided them into five classes of chemicals, two of which were found to be more common than the rest: phthalates and flame retardants. 
 
 "Many of the top 10 fall into these two categories," Zota said. 
 
 But when factoring in the wide range of chemicals we're exposed to, small amounts can add up, she stressed. 
 
 Lurking in the dust 
 
 The chemicals found in dust samples came from a range of things typically found inside your home, including vinyl products -- such as flooring -- cosmetics, baby products, furniture and nail polish. 
 
 To understand how these chemicals are entering your home, it helps to understand where they are used. Phthalates make plastic softer and more flexible, so they tend to be found in vinyl (PVC) materials such as flooring, blinds and food packaging. Flame retardants help products meet flammability standards that are built into building codes, insurance requirements and fire regulations. 
 
 The other three classes of chemicals found in dust samples included environmental phenols, usually used as preservatives in personal care products like shampoo; fluorinated chemicals, used as stain- and water-repellent treatments for upholstery, carpets and clothes and in nonstick pans; and fragrances. 
 
 Only one chemical used in fragrances had been the topic of a study, meaning many more chemicals are likely to be present in dust with little insight into them, according to the researchers. "We know very little about the health hazard of these fragrances," said Zota. 
 
 But the researchers note that it is about more than exposure. For example, phthalates were detected in the highest concentrations in the study, but the chemicals found in flame retardants had the "highest estimated intake," meaning they are more likely to enter the body. 
 
 "You can breathe it in and can absorb into your skin," Zota said. "These chemicals are not bound to the products, so they can migrate out." 
 
 A risk to child development 
 
 One of the biggest concerns underlying the presence of these chemicals hiding in house dust is the fact that children are most likely to inhale or ingest them as they crawl around, touching things and inevitably placing their hands in their mouths multiple times a day. 
 
 "Environmental insults during early development can have long-lasting adverse health effects that persist across the lifespan," Zota said. Phthalate exposure in children "can increase risk of respiratory, behavioral and neurodevelopmental problems." 
 
 Phthalates are also known to disrupt hormones inside the body, meaning they could cause reproductive problems. 
 
 "We know from lead that exposures are not acceptable," said Dr. Asa Bradman, associate director for exposure assessment at the Center for Environmental Research and Child's Health at the University of California, Berkeley, who was not involved in the new study. 
 
 "There's a strong argument to reduce exposure to children whose brains are changing and bodies are developing." 
 
 As for the study findings, Bradman noted that the reason phthalates were found to be most common in house dust was probably because most studies have been done on this class of chemicals. 
 
 "By compiling information in this way, there's always the possibility of exposures that haven't been studied yet," Bradman said. 
 
 Preventing exposure 
 
 Some advice to prevent exposure, other than regularly dusting your home, is to veer away from the traditional feather duster and use a powerful vacuum with a HEPA filter to ensure that all dust particles are sucked up. Regular hand-washing -- which has a multitude of benefits -- will also reduce exposure to flame retardants found on the surfaces of furniture. 
 
 The Silent Spring Institute has created an app to help people understand more about their environmental exposures, aptly named Detox Me 
 
 Join the conversation See the latest news and share your comments with CNN Health on Facebook and Twitter. 
 
 But both Zota and Bradman stress that there needs to be more research into the range of chemicals people are exposed to at home and changes at the policy level to reduce the number of chemicals entering people's households, through bans, better regulation and improved underlying chemistry during production. 
 
 "There may be chemicals out there that we don't know about, that we should know about," said Bradman, whose own research looks into exposure risks, particularly among children. His studies have found phthalates to be common in child care practices in the United States. 
 
 "But we can also reformulate materials so that chemicals don't just go into our bodies," he added. "There may be ways to have better adhesion [of flame retardants to furnishings] so they don't get into the environment." 
 
 The issue is also not specific to the United States. 
 
 "These consumer product chemicals are widely used throughout the globe and have been detected in homes in the UK and other European countries," Zota said, adding, "since the European Union has different chemical regulations than the US, the average levels for some of the chemicals may be different than those we found for US homes." ||||| A new peer-reviewed study found that people are contaminated with several toxic flame retardants rarely studied in the US, including one that has never before been detected in Americans called TCEP. Scientists tested urine samples of California residents for biomarkers of six chemicals, all of which were present. 
 
 The scientists discovered a way to test for this class of toxic flame retardants (phosphates), which could open up a new wave of research into a group of pervasive flame retardants that were previously not studied nearly as much as some other flame retardants. 
 
 Funded in part by the National Institutes of Health (NIH), the study by researchers at Silent Spring Institute and the University of Antwerp was published online today in the peer-reviewed journal Environmental Science & Technology. 
 
 "We found that several toxic flame retardants are in people's bodies. When you sit on your couch, you want to relax, not get exposed to chemicals that may cause cancer," said lead author, Robin Dodson, ScD, a scientist with the nonprofit research group Silent Spring Institute. "Some flame retardants have been targeted for phase out, but unfortunately there are others that have largely been under the radar." 
 
 Fortunately, furniture without flame retardants is now available since the State of California recently revised its flammability standard after a public health outcry. The earlier standard resulted in high levels of flame retardants used in upholstered furniture across the country without appreciably improving fire safety. Hopefully levels of the chemicals in people's bodies will decrease as consumers are able to choose flame retardant-free furniture. 
 
 The chemical detected in Americans for the first time, TCEP [tris-(2-chloroethyl) phosphate], is a carcinogen and can also harm people's nervous and reproductive systems. The biomarkers for the chemical were detected in the urine of 75% of the people tested. More than a half a million pounds of TCEP are produced every year for use in polyurethane foam, plastics, polyester resins and textiles. It is listed under California's Proposition 65 as a carcinogen and the European Union has classified it as a "Substance of Very High Concern." 
 
 Another carcinogenic chemical detected in the study is similar to TCEP, like an "evil cousin," called TDCIPP (chlorinated "tris"). Some had expected that it wouldn't be so prevalent because they thought its production diminished after it was phased out of children's pajamas years ago. Arlene Blum, PhD, Executive Director of the Green Science Policy Institute and Visiting Scholar at UC Berkeley, said, "It is hard to believe that a metabolite of chlorinated tris, the same flame retardant we helped remove from baby pajamas in the 1970s, was found in almost all of the study participants. It is such good news that, thanks to the new flammability standard, such harmful chemicals are no longer needed in our furniture." 
 
 This study adds to a previous analysis of flame retardants in dust samples that were taken from homes of the same people whose urine was tested. The researchers chose to test urine samples for this class of phosphate flame retardants after seeing a high prevalence of them in the dust, and recognizing the dearth of information on this group of chemicals. In the household dust, half of the homes exceeded EPA health guidelines for either TCEP or TDCIPP. 
 
 Another interesting finding from this new study is that the people with the highest level of TCEP and TDCIPP metabolites in their urine live in homes that had the highest quantity of the respective chemical in dust. 
 
 "This study provides more evidence that our homes are a primary source of exposure to toxic flame retardants," said Julia Brody, PhD, Executive Director and Senior Scientist at Silent Spring Institute. 
 
 Tony Stefani, President of the San Francisco Firefighters Cancer Prevention Foundation, said, "It has been proven that flame retardants do not provide the level of protection necessary to save lives and property. We have known how toxic these chemicals are for decades and yet they are still being used. 
 
 "It disturbs me that Californians have cancer-causing flame retardants in their bodies. Another recent study showed San Francisco firefighters had higher flame retardant levels in their blood than the general population of California. We feel that these chemicals are a very large piece of a toxic, complex chemical puzzle we encounter when fighting a fire." 
 
 Brody described some good news that came from the research: "There has been a breakthrough in that we now know what to look for when trying to figure out if someone has these toxic chemicals in their bodies. This should open up future research on several toxic flame retardants that haven't been scrutinized enough before." The study identifies which biomarkers to look for in urine for each chemical to indicate the presence of the contaminant. 
 
 Rachel Gibson, Director of the Safer Chemicals Program at Health Care Without Harm, commented, "We are pleased to see furniture manufacturers taking steps to remove flame retardants from their products, as a result of California's new flammability standard. In support of the Healthier Hospitals Initiative, already five major health systems have pledged to buy furniture without these toxic chemicals." Those systems include Advocate Health Care, Beaumont Health System, Hackensack University Medical Center, Kaiser Permanente, and University Hospitals. 
 
 What Can Consumers Do? In addition to asking companies for flame retardant-free sofas at retailers like IKEA and Williams-Sonoma, which will begin selling these products early next year, consumers can also reduce their risk by cleaning surfaces with a wet cloth or mop and vacuuming with a HEPA filter, as these chemicals are emitted into the air and collect in dust. Consumers can also skip foam padding under carpets or request padding without flame retardants. People should also throw away foam that is deteriorating, as it likely sheds even more of the chemicals. 
 
 Senator Schumer recently introduced the Children and Firefighters Protection Act of 2014 (S.2811). The bill prohibits use of 10 designated flame retardants, including the three chlorinated phosphate flame retardants found in this study, in children's products and upholstered furniture. 
 
 ### 
 
 The study was funded by the National Institute of Environmental Health Sciences, The New York Community Trust, the Fine Fund, and Art beCAUSE Breast Cancer Foundation. 
 
 ATTENTION REPORTERS: More details, including tips for reducing exposure, are available. Scientists involved in the study and others who can comment on it are available for interviews. ||||| A strange catastrophe struck Spain's pig farmers in the spring of 2010. On 41 farms across the country—each home to between 800 and 3,000 pigs—many sows suddenly ceased bearing young. 
 
 On some farms, all the sows stopped reproducing. On others, those that did become pregnant produced smaller litters. 
 
 When investigators examined the sows and the semen that had been used to artificially inseminate them—it had been collected from different boar studs and refrigerated—they couldn't find anything wrong. The sperm cells weren't misshapen. None of the sows were diseased. No microbes or fungal toxins were detected in their feed or water. 
 
 Only one factor was common to all the farms and studs: The plastic bags used for semen storage all came from the same place. 
 
 Investigating those bags has led Cristina Nerín, an analytical chemist at the University of Zaragoza who studies packaging materials, to publish new research that traces the pigs' infertility to chemical compounds in the plastics. 
 
 This is "the first time that the correlation between reproductive failures and compounds migrating from plastic materials [has been] studied and demonstrated," says Nerín, whose team published last month in the journal Scientific Reports. 
 
 The implications could extend far beyond the farm. 
 
 Some of the same chemicals found in the pigs' semen storage bags are routinely used in packaging food for humans and are known to migrate into food. The strange case of the Spanish pigs, Nerín says, "shows the real risks we face." (Explore an interactive showing toxic chemicals that may be lurking in your home.) 
 
 Not Just About Pigs 
 
 Cyclic lactone, for instance, is a common by-product in adhesives used in potato chip bags and sliced meat packages. It was one of the chemicals found in high levels in the semen bags that had been used on the farms with the highest rates of reproductive failure. 
 
 Another chemical found in high levels on those farms: a compound called BADGE, a derivative of the notorious bisphenol A (BPA). It's the building block of epoxy resins that form the basis for 95 percent of food and beverage can linings in the U.S. (Also see "Chemical BPA Linked to Heart Disease, Study Confirms.") 
 
 In one recent study led by analytical chemist Kurunthachalam Kannan of the New York State Department of Health in Albany, BADGE, which is also found in household dust, was detected in 100 percent of 127 urine samples collected from people in the U.S. and China. 
 
 BPA, the precursor of BADGE, is a known endocrine disruptor: It mimics and interferes with the action of a human hormone, in this case estrogen. A derivative of BADGE called BADGE-2H2O—which forms when BADGE meets water—is an even more potent estrogen mimic. 
 
 A lot of research—epidemiological, lab-animal, and clinical studies—has linked endocrine disruptors to adverse health effects, including abnormal testicular development, early puberty, prostate cancer, breast cancer, and even obesity. 
 
 View Images A researcher says her study is the first to show a correlation between reproductive failures and chemicals migrating from plastics. Photograph by Ervin Sarkisov, Rex Features/AP 
 
 Damaging DNA? 
 
 Nerín thinks the suspect chemicals in the pigs' bags came from adhesives used to glue together the multilayer plastic that made up the bags. But the chemicals in question aren't normally used for that purpose. Their presence in the Spanish pig semen bags may reflect some kind of unusual contamination. 
 
 The supplier of the bags, a company named Magapor, had contacted Nerín because of her expertise. "They were desperate," she says, "because they didn't find a reason why reproduction failed." 
 
 Nerín confirmed her suspicion that the high levels of cyclic lactone and BADGE were to blame by "spiking" a new batch of semen with a mix that included those two chemicals and inseminating two groups of 50 sows with either the spiked mixture or a control. Just 58 percent of the sows inseminated with the spiked semen became pregnant, compared with 84 percent of the controls. 
 
 Magapor had purchased the semen storage bags from a Chinese manufacturer. When the company switched to a different bag producer, the Spanish pigs' fertility returned to normal. 
 
 To complicate the story further, Nerín didn't find any evidence that BADGE was acting as an endocrine disruptor at the levels at which it was present in the semen bags. But lab experiments suggest BADGE is a mutagen as well as an endocrine disruptor: Besides binding to hormone receptors inside cells, it can bind to DNA, causing mutations. 
 
 Because the sperm cells in Nerín's pig study looked normal and moved and penetrated eggs normally, she believes many of the pregnancy failures may have resulted from damage to the sperm's DNA—which somehow caused fertilized embryos not to develop normally and not to implant in the sow's uterus. 
 
 Effects in Humans? 
 
 Meanwhile another paper published last month revealed a specific mechanism by which endocrine disruptors might indeed interfere with fertilization in humans. 
 
 One of the authors, physician Niels Skakkebaek of the Rigshospitalet, a university hospital in Copenhagen, has been studying testicular disorders and endocrine disruptors for decades. In a 1992 paper in the British Medical Journal, he reported evidence indicating that sperm quality had deteriorated among men in the United States and elsewhere over the previous 50 years. 
 
 In the new study, Skakkebaek; Timo Strünker of the Center of Advanced European Studies and Research in Bonn, Germany; and their colleagues exposed human sperm in lab tests to 96 common endocrine disruptors—chemicals, they write, that are "omnipresent in food, household, and personal care products." 
 
 They looked at the effects of the chemicals on a specific signaling conduit in sperm (and other cells) called a calcium channel. The calcium channel in sperm is usually activated by female hormones in the female reproductive tract, including progesterone released by cells surrounding the egg. Activation of the calcium channel allows calcium ions to flood into the sperm cells, which in turn affects their motion, causing them to swim toward an egg and penetrate it. 
 
 Skakkebaek and Strünker found that about one-third of the chemicals they tested in the lab evoked a "sizable" response by the calcium channel. 
 
 For example, some caused the sperm's tail to curl up rather than flick from side to side. The chemicals that had the strongest effects included ultraviolet light-filtering agents in sunscreens; plastic-softening phthalates used in food and drink containers; and fungicides and antibacterial compounds such as triclosan, which are commonly found in soaps, toothpaste, and toys. 
 
 "That was quite unexpected to find so many that could have an effect," Skakkebaek says. "This is the first time this has been shown." 
 
 If endocrine-disrupting chemicals are present in the female reproductive tract, Skakkebaek says, they may desensitize the sperm to signals from progesterone. "The sperm cells may have more difficulty in sensing where the egg is," he says. "They could also be swimming in the wrong direction, because they had wrong signals on the way." 
 
 That, in turn, might disrupt the process of fertilization. 
 
 Skakkebaek's lab tests, like the Spanish semen bags, placed the suspect chemicals in direct contact with sperm cells. But it's not known whether those chemicals are in fact present in the female reproductive tract in dangerous concentrations. 
 
 Some researchers question whether everyday exposure to such chemicals in food packaging, say, would have the same detrimental effects on sperm; after the chemicals were ingested, they would be metabolized in the human body, which could change their structure and toxicity. 
 
 One skeptic is Allan Pacey, a senior lecturer in andrology at the University of Sheffield in the U.K. He and his co-workers conducted two large epidemiological studies on thousands of British men, examining both occupational exposures to chemicals and lifestyle issues, such as drinking and smoking. They found that only two risk factors—exposure to glycol ether (a paint ingredient) and wearing tight underwear—were associated with "low motile sperm count." 
 
 "It is possible to measure effects on ejaculated sperm in the lab, but this is a long way removed from what may be happening in the real world," Pacey says. 
 
 Skakkebaek agrees that more studies of how chemical exposure affects actual humans are needed. 
 
 "Most of these chemicals are found in almost everybody," he says, referring to the ones in his recent study. "We know for sure that they are in our bodies, because we know for sure that they are excreted in our urine. But what we don't know for sure is the concentration." 
 
 As for Nerín's study of the Spanish pigs, "they really found a clear association" between chemical exposure and infertility, Skakkebaek says. "I believe it should be taken as a warning." ||||| Consumers’ Guide to Highly Fluorinated Chemicals 
 
 Why are highly fluorinated chemicals harmful? Highly fluorinated chemicals contain carbon-fluorine (C-F) bonds, which are some of the strongest bonds in nature. That makes them both incredibly resistant to breakdown and very useful. For instance, they can make products grease or stain-resistant, nonstick, or waterproof. However, this comes at a cost. The highly fluorinated chemicals that have been well-studied have been associated with: Watch our new video 
 
 
 
 To learn more, watch our short webinar testicular and kidney cancer 
 
 liver malfunction 
 
 hormonal changes 
 
 thyroid disruption high cholesterol 
 
 obesity 
 
 ulcerative colitis 
 
 lower birth weight and size Other highly fluorinated chemicals are suspected of similarly causing health problems, but have not been well tested. Because they are resistant to breakdown, these chemicals can persist in our bodies for years. In the environment, they can last for millions of years. This means that the highly fluorinated chemicals released during our lifetimes will build up in the environment, and many future generations will be exposed to them, at even higher levels than we are today. Scientists from all over the world signed the Madrid Statement to share their concerns about highly fluorinated chemicals and are asking for a limit to the production and use of these chemicals. Find out more here On May 1, 2015, the Madrid Statement was published in Environmental Health Perspectives, a high-impact scientific journal. Click here to read the article, here to read an accompanying editorial by distinguished scientists Linda Birnbaum and Phillipe Grandjean, here to read the reply from the chemical industry, and here for our response. 
 
 How are we exposed? 
 
 Highly fluorinated chemicals are used in consumer products such as cookware, clothing, outdoor apparel, carpeting, and food packaging to provide nonstick, oil- and water resistant properties. They are also used in some kinds of cosmetics. 
 
 We are exposed to them by direct contact with these products, but also through the air we breathe, the water we drink, and the food we eat. 
 
 They have been detected at high levels in humans and wildlife all over the globe. 
 
 What can you do? Ask yourself, “Do I really need products that are stain-resistant, nonstick, or waterproof?” Knowing the consequences, you might choose to give up some conveniences or product performance. Steps you can take: Avoid products that are oil repellant or stain resistant. 
 
 Only purchase waterproof gear when you really need it. 
 
 Avoid cosmetics with PTFE or any word containing “perfluor” or “polyfluor” on their ingredients list. 
 
 Replace your Teflon nonstick cookware with cast iron, glass, or ceramic. 
 
 Avoid microwave popcorn and greasy foods wrapped in paper. 
 
 Tell retailers and manufacturers you want products without fluorinated chemicals. 
 
 Support companies committed to phasing out highly fluorinated chemicals, such as the apparel brands that have joined Greenpeace’s Detox campaign, and the fast food chains that removed them from food packaging as a result of EWG’s action. All products from these apparel brands will be free of highly fluorinated chemicals after those dates. You can drive change for healthy products! 
 
 Resources 
 
 In the Media
– We're surrounded by toxic chemicals, and even holing up in our meticulously kept homes may not save us, Time reports. Ten chemicals that may be hazardous to our health were found in over 90% of indoor dust samples taken for a study published in the Environmental Science & Technology journal. And these chemicals are found in everyday items, including ones you may suspect (e.g., cleaning products, cellphones) and ones that may surprise you (toys, pizza boxes). Two of the most common toxins are phthalates—chemicals used to make plastics more flexible and thought to be linked to harmful effects on the endocrine system, which can lower IQ and lead to breathing troubles—and highly fluorinated chemicals, or HFCs, used to make items nonstick or waterproof but which are also tied to testicular and kidney cancer, thyroid issues, and liver malfunction, among other problems. In what the study's authors say is the first mega-study of its kind, they scrutinized data from 26 past studies and one unpublished one, with dust containing 45 chemicals collected from homes, schools, and workplaces in 14 states, per Scientific American. The Toxic Substances Control Act was updated earlier this year, per the Atlantic, but the law only requires new chemicals get a green light from the EPA—leaving about 1,000 examination-worthy chemicals already on the market that the agency doesn't have the resources to study. "We think our homes are safe havens, but … the surprising reality [is] that our homes are being polluted by the products we have every day," co-author Veena Singla tells CBS News. How you can decrease your risk, the authors say, per CNN: Wash your hands regularly and use a strong vacuum with a HEPA filter. (Arkansas prisoners fear they were exposed to toxic dust.)