Shift work linked to fertility problems in new study

Millions of women in the United States are shift workers, following schedules that are beyond the typical 9 to 5, but little is known about how their hours can affect their reproductive health and fertility.

Now, a surprising new review of previous studies suggest that shift work can take a serious toll.

According to a study presented at the annual meeting of the European society of human reproduction and Embryology in London this week, women who work irregular shifts are more likely to experience reduced fertility and increased menstrual disturbance. Women who work nights may specifically have an increased risk of miscarriage.

"Nobody who works shifts has changes in biological function, and could be one of a number of things which has an impact on the ability of women to play," Dr. Linden Stocker, researcher at the University of Southampton in the United Kingdom, told The Huffington Post.

Stocker and colleagues reviewed 14 published studies between 1969 and 2013 that investigates the links between shifts and spontaneous abortions, menstrual disorders (defined as cycles of less than 24 days and cycles of 32 or more days) and not get pregnant after a year of trying of. All together, the studies included nearly 120,000 women.

Irregular schedule - Stocker defined as anything out of 8 to 18 - was linked to an increased rate of 33 per cent of menstrual disorders and one rate higher than 80 percent of Subfertility.

Working nights was not particularly tied to menstrual problems or problems getting pregnant, but was linked to an increased risk of miscarriage.

The researchers described the results as the novel, but warned that it should not be oversold. "We have not shown causality; We have found an association, warned the Stocker.

The women who work irregular shifts or nights can participate in any number of behaviors that could be influencing reproductive outcomes. For example, working hours is often linked to loss of sleep, decrease of exercise and poor diet.

But a growing body of research suggests that the physiological changes that accompany the work shift may be the culprits and that reproductive problems are a direct result of interrupted circadian rhythms.

In a preliminary study published last year, researchers manipulated the patterns of light and dark mice were exposed to it to test what effect, if any, this would have on their fertility. A group of mice subjected to repeated changes in its cycle of light / darkness had a success rate of pregnancy of just 22 per cent, compared to a success rate of 90 percent among a group of mice exposed to a typical day/night pattern.

"We were surprised, dramatically, the effect of manipulating the cycle was light-dark," said Keith Summa, researcher at Northwestern University and author in that study, in a statement. "We expected a negative effect of the disruption of the circadian clock, but not both."

Some estimates suggest that up to 15 million Americans take turns regular, including more and more women. According to the work of Sloan and research network of the family at Boston College, nearly one-third of companies with extended hours reported an increase in the number of workers by turns female in a 2004 study. Doctors and nurses often work irregular hours, as pilots, police officers, firefighters, employees of the restaurant and retail and home health aides.

Stocker said that women who work in shifts should not emphasize on the new findings, particularly until future studies have replicated the results.

"We know that many things can help improve reproductive outcomes - a balanced diet, exercise and take care of yourself in general," said. "While we hope that future studies prove or disprove our conclusions, it is important that women are focused on your health in general."

Gun Violence Study Links State Levels Of Gun Ownership And Homicide

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A new study of gun violence published by the American Journal of Public Health found that states with greater levels of gun ownership tend to have higher rates of gun-related murder.

The study, conducted by Boston University professor Michael Siegel and coauthors Craig S. Ross and Charles King III, examines this relationship in all 50 states from 1981 to 2010. The researchers found that "for each percentage point increase in gun ownership, the firearm homicide rate increased by 0.9 percent."

The authors note that, though they can't prove a causal relationship between higher levels of gun ownership and homicide, "states with higher rates of gun ownership had disproportionately large numbers of deaths from firearm-related homicides."

Their findings echo past studies about the relationship between gun ownership and homicide, though Siegel, Ross and King look at the relationship over a larger window of time than previous research.

According to a fact sheet from the Harvard School of Public Health:

Our review of the academic literature found that a broad array of evidence indicates that gun availability is a risk factor for homicide, both in the United States and across high-income countries. Case-control studies, ecological time-series and cross-sectional studies indicate that in homes, cities, states and regions in the US, where there are more guns, both men and women are at higher risk for homicide, particularly firearm homicide.

A more localized 1993 study published in the New England Journal of Medicine, which focused on the most populous counties in Tennessee, Washington and Ohio, found that "keeping a gun in the home was strongly and independently associated with an increased risk of homicide."

(h/t ThinkProgress)

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Chlamydia Can Cause DNA Damage Linked With Cancer Risk, Study Finds

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By: Rachael Rettner, LiveScience Senior Writer
Published: 06/21/2013 12:17 PM EDT on LiveScience

Chlamydia infections can cause DNA damage that may increase the risk of later developing cancer, a new study suggests.

In the study, human cells growing in lab dishes that were infected with chlamydia were more likely to have DNA damage compared to cells not infected with chlamydia. What's more, this DNA damage was not always repaired properly by the cell, increasing the chances of genetic mutations.

Normally, cells with such DNA damage would activate a process that kills the cells, so that the cell does not turn cancerous. But in the study, the cells with DNA damage overrode this mechanism, and continued to divide. The continued division of cells with DNA mutations could eventually lead to cancer, the researchers said.

Earlier studies found an association between chlamydia infections and an increased risk of cervical and ovarian cancer in people, but such studies cannot prove cause and effect. The new study provides a biological explanation for how chlamydia could increase the risk of cancer.

However, because the study was conducted in cells in a lab dish, more research is needed to show the same thing occurs in people.

The new study, conducted by researchers at the Max Planck Institute for Infection Biology in Berlin, was published June 12 in the journal Cell Host & Microbe.

Chlamydia is a sexually transmitted disease caused by the bacteria Chlamydia trachomatis. Most infected people have no symptoms, according to the Centers for Disease Control and Prevention. However, untreated infections can damage the reproductive tract in women, and cause infertility. Complications from untreated infections are rare in men, but the condition can cause a burning sensation when urinating, and very rarely, prevent a man from fathering children, the CDC says.

Follow Rachael Rettner @RachaelRettner. Follow LiveScience @livescience, Facebook & Google+. Original article on LiveScience.com.

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Ugly people harassed at work? Study shows little attractive employees more likely to be abused

A new study by the Michigan State University has discovered a terrible truth about the American workplace: looks do matter.

The researchers found that employees who are considered unappealing are more likely to be despised and harassed at work. While a lot of research has found that attractive students tend to be more popular in school, the study is the first to link the level of attraction to cruelty in the Office.

"Although we like to think that we are professional and mature in the workplace, can be just as high School in many ways," said Brent Scott, one of the researchers of the study lead.

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As part of the study, 114 workers surveyed researchers in a center of health in the United States Southeast over the frequency with their coworkers to cruel behavior towards them, which included saying hurtful things, acting rudely and mocking them. In addition, the researchers had people who do not know the participants of the survey to judge its attractions of digital photos.

They found that unattractive workers treated much more harshly that attractive employees even when other key factors were taken into account, such as age, gender and how long had worked in the health care facility.

The researchers also collect information upon how pleasant or environment of the workers were based on questionnaires completed by their spouses, partners or friends. The results show that unpleasant workers, as unappealing employees, were treated more harshly than their coworkers.

"Our results revealed that personality and appearance matter," said Scott.

Based on the study, managers should have a better idea that employees are potential targets for preventing such behaviour, or be able to provide advice and social support if they fail attempts at prevention, said Scott.

The results of the study have recently published in the journal of Human Performance research.

Chad Brooks of follow on Twitter @cbrooks76 or elEconomista.es @BNDarticles. We are also on Facebook & Google +. This story was originally published in elEconomista.es.

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Non-Maternal Urges Linked To Higher IQ In Controversial Study

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A British researcher made waves in the blogosphere this week after his study regarding maternal urges and intelligence was shared on the Internet.

Satoshi Kanazawa, an author and researcher at the London School of Economics and Political Science, suggested that the higher a woman's IQ, the lower her desire to reproduce, according to an article published in the Daily Mail.

The numbers dovetail with recent results from Britain's Office of National Statistics concluding more women than ever are deciding to remain childless, The Telegraph notes.

Kanazawa did not respond to a Huffington Post request for comment, so the exact nature of his study cannot be independently verified. However, he made very similar assertions in his 2012 book, The Intelligence Paradox: Why the Intelligent Choice Isn't Always the Smart One.

In a chapter called "Why intelligent people are the ultimate losers in life," Kanazawa notes that "more intelligent women are significantly more likely to remain childless -- and significantly less likely to become parents -- than less intelligent women."

According to Kanazawa, the "mean childhood IQ of women who have remained childless for life is 105.3, whereas the mean childhood IQ of women who have become parents is 101.7. The difference in mean childhood IQ between the two categories of women is very large and statistically significant."

The research is by no means unassailable, however.

Kanazawa uses statistics compiled from the U.K.'s National Child Development Study and measures intelligence based on IQ. This method is not foolproof, notes blog xoJane, which cites studies showing IQ is not the ultimate measure of intelligence.

There's also the matter of a past scandal involving a very controversial Kanazawa study that suggested black women are less attractive. After a backlash, Kanazawa was fired from his position at Psychology Today.

Finally, The Guardian's Sadhbh Walshe says Kanazawa appears to be making a troubling value judgment about women who choose not reproduce.

"It seems that this research is just adding fuel to the argument that women who don't have children, regardless of the reason, are not just selfish losers but dumb ones as well," Walshe writes, citing The Intelligence Paradox. "Kanazawa finds it paradoxical that intelligent women apparently don't possess the desire to pursue what should be the ultimate goal of their biological existence."

The concerns of many women -- not to mention mothers -- may be most accurately summed up by Al Arabiya columnist Ahlya Fateh.

Staring down the Daily Mail's examples of outspokenly "childless" women, including Cameron Diaz and Eva Mendes, Fateh jokes that her two children have caused her a fair share of stress and brain-cell loss and wonders if Kanazawa would consider her "sub-human on the intelligence scale."

On a more serious note, however, Fateh recounts the recent experience of her friend becoming a mother later in life.

"I received a text while I was in New York, 'He has arrived and I am so in love with him," Fateh wrote. "This told me everything I needed to know; there is a mother in all of us, she’s just waiting to be born and it doesn’t have a thing to do with her IQ."

She does, however, point out that she has "many friends who are unmarried and have chosen not to have children and are genuinely happy with their decisions."

Autism, Air Pollution Link Confirmed By First National Study

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Living in an area with high levels of air pollution may increase a woman's chances of having a child with autism, according to the first national study to date that investigates the possible link.

"Women who were exposed to the highest levels of diesel or mercury in the air were twice as likely to have a child with autism than women who lived in the cleanest parts of the sample," study author Andrea Roberts, a research associate with the Harvard School of Public Health, told The Huffington Post.

Earlier studies have established a potential connection between air pollution and autism risk, but have concentrated on a few individual states. The latest study, published in the journal Environmental Health Perspectives on Tuesday, draws on a large sample of women across the whole country.

Researchers crossed U.S. Environmental Protection Agency data on the level of air pollutants from year to year with data from the Nurses' Health Study, one of the longest running investigations of women's health in the U.S. They looked for associations between levels of pollutants in the time and place that a woman was pregnant and whether that woman went on to have a child with a diagnosed autism spectrum disorder.

The researchers split up the locations into fifths, and women who lived in the most polluted sections -- those with the highest levels of diesel particulates or mercury in the air -- were twice as likely to have a child with autism compared to those in the cleanest sections. Other types of air pollution, including lead, manganese and other hard metals, were also linked to a greater risk of autism, although the risk was not quite as high.

"All of the chemicals studied are known neurotoxins," Roberts said. "They are also known to pass from mother to baby while a woman is pregnant. It's very plausible that the 'stuff' the mother is taking in through the air is affecting her baby's brain development."

But the researcher cautioned against reading too much into the results, particularly with regard to mercury. Many parents continue to worry that the form of mercury sometimes used in vaccines is linked to autism -- although that claim has been repeatedly disproven by research efforts.

"Our data is not good enough to know which thing in the air might actually be causing this [link], if it even is something in the air that is increasing the risk of autism," Roberts said. "It might be that it's actually diesel that's [behind] the problem. We are skeptical about the possibility of mercury being causal in this way, through the air."

Alycia Halladay, the senior director for environmental and clinical sciences for the advocacy group Autism Speaks, said that "in terms of how [air pollution] is linked to autism, that's not something we're able to specifically define."

"We can make a lot of hypotheses, but we don't really know," added Halladay, who did not work on the study.

The next step, which would represent a crucial step forward, is to look at blood samples of both mothers and their babies to see what chemicals are actually being absorbed, Roberts said. Only then can researchers assert with any real certainty that the link exists, and begin to understand which specific air pollutants are the most damaging.

The cause of autism is not yet known, although researchers suspect that a combination of genetic and non-genetic factors, such as parental age and complications during pregnancy could all play a roll.

For now, there are few specific steps women living in high-pollution areas can take in order to mitigate their risk.

"There are things any doctor or health care professional would tell you to do," Halladay said. Those include eating well, taking a prenatal vitamin, getting regular prenatal health care check-ups and staying away from sick people or viruses as much as possible.

"This is just a change in risk," she said, "it's certainly not a cause."

Sibling Bullying As Detrimental As Peer Bullying, Study Claims

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Sibling squabbling is a rite of passage. Brothers and sisters argue; they roughhouse; they steal each other's clothes and toys.

But a provocative new study claims that even mild acts of sibling aggression are just as detrimental as the bullying that many children face at school.

"Historically [sibling bullying] has been accepted as something that's normal, as something that's benign. Oftentimes it's just dismissed," study author Corrina Jenkins Tucker, an associate professor of family studies at the University of New Hampshire, told The Huffington Post. "Some people actually view it as a good thing, thinking it teaches kids how to fight and develop conflict resolution skills."

The new study, published online Monday in the journal Pediatrics, suggests otherwise.

In telephone interviews, researchers asked more than 3,500 children 17 and younger, or their caregivers, whether they'd exeperienced at least one act of sibling aggression in the past year. It could include psychological bullying, property damage, physical fighting (with no weapons that resulted in no injuries), and more serious physical assault.

Researchers questioned participants about feelings of depression, anxiety and anger. Children who experienced even just one, relatively mild act of sibling agression in the past year reported greater mental health distress than those who had not. Kids aged 9 and under were more distressed after experiencing physical aggression than their teenage counterparts, but all age groups were equally affected by other forms of bullying.

The new study is the first major investigation of the consequences of sibling aggression, which is generally considered less serious or harmful than the peer bullying that children may face online or in school.

"This is an extremely important study for parents, psychologists, and pediatricians," said Susan Swearer, who did not work on the study, but is a professor of school psychology at the University of Nebraska-Lincoln and co-director of the Bullying Research Network. "The findings clearly connect sibling aggression with youth mental health difficulties."

The difficulty for parents and health care providers is distinguishing between "normal" fighting among children who are growing up together under one roof, and something more serious.

"This study examined sibling agression [but] not sibling bullying, per se," said Amanda Nickerson, director of the Alberti Center for Bullying Abuse Prevention at the University at Buffalo, who did not work on the new research. "To assess bullying, it is important to assess the intent of the aggression -- was it done to cause harm? -- the repetition of it and the power imbalance between the perpetrator and the victim."

For example, Nickerson said, it is common for brothers and sisters to argue over who gets what items and privileges, such as picking TV shows, as well as for them to annoy each other. However, if a child's aggression is aimed at intentionally hurting a sibling physically or psychologically, then it is different. Repeated behaviors are also a red flag, Nickerson added.

The Centers for Disease Control and Prevention has identified bullying as a major public health concern, citing estimates that suggest nearly 30 percent of adolescents in the U.S. have either been a bully, been the victim of bullying, or both. Children who are bullied are at greater risk for depression and anxiety that may last into adulthood, as well as lower academic scores and broader health complaints. Being a bully also carries health risks: Children who are the agressors are more likely to abuse alcohol or drugs as they get older, engage in early sexual activity and abuse their partners or children.

Jenkins Tucker and her colleagues hope to next explore how long the mental health effects last and whether patterns vary according to birth order or gender.

But outside experts hail the new study as an important first step.

"This study is the first to unequivocally show that sibling aggression is connected to mental health problems among youth," Swearer said. "In order to effectively treat mental health problems in youth, parents and mental health providers must recognize and understand the role that sibling aggression plays."

Eric Uhlfelder: A Picture of Autumn: The Mint Theatre's New Production Is a Study of Home

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Coming to New York's Mint Theatre is like tuning into a classic movies channel, except productions are rarely familiar. It has been artistic director Jonathan Bank's mission to unearth forgotten small theatrical gems from decades past.

A Picture of Autumn, British playwright N.C. Hunter's first play, would seem to have the pedigree. After all, Hunter went on to write subsequent West End productions that starred the likes of Sirs John Gielgud and Ralph Richardson. And on Broadway, Jessica Tandy and Hume Cronyn brought his words to life.

The Times of London credited the 20th-century playwright as "a writer who brought a new tone and unfamiliar nuances into the English theatre." Just knowing Autumn had never seen an American stage likely made the Mint artistic staff downright giddy.

Set in the Mint's typically well-crafted stage capturing worn elegance of a British country estate's main living room, the audience is introduced to an elderly couple, Sir Charles and Lady Margaret Denham, played genially by Jonathan Hogan and Jill Tanner. Also present is the husband's eccentric yet occasionally clear-minded brother Harry [George Morfogen], and a fiercely kooky, independent nameless servant, played frighteningly well by Barbara Eda-Young.

The four are the only souls occupying the 18-bedroom spread. It's far too big and costly for them to manage, and it has gone much to seed both inside and out. With the house having been in the family for two-centuries, the issue that drives the story is summed up Bard-like by Henry: "To move or not to move?"

Despite his romantic penchant, Henry coolly observes the drama being played out as "farce, not tragedy." And if the family doesn't take the buyer's offer and stays on, he wonders if they won't end up living out their days in regret.

Of course he's right on both counts, especially when one realizes the play was written just several years after the end of the Second World War. With British cities and towns still reeling after endless bombing, the tale is a bit escapist, colored with plenty of screwball. Certainly the playwright (a war veteran himself) thought it was as good a time as any to see how the aging aristocracy was getting on.

The Mint likely saw the play's timeless theme as one that would touch it's own elderly patrons and regulars. Deciding whether or not to give up one's home that shelters decades of memories can be heart-wrenching trauma. Oddly, the family is oblivious to how fortunate it is to have a solid roof over its head in the first place. But let that go, and the story's charming zaniness starts to grab hold. And by the end of the first act, Hunter seems to turn from this singular focus.

Uncle Harry suddenly sees the spitting image of his bride lost 60 years prior, reincarnate in his great niece, Felicity [Helen Cespedes]--the daughter of his brother's son Robert [Paul Niebanck] -- descending the grand staircase. One almost wants to rub one's hands in anticipation to where the playwright plans to take us.

In their ability to span such a large gulf in age, these two share some of the play's most touching moments Their meeting propels the collision of generations -- an ode to the house as it were -- as all characters are prompted to look both forwards and backwards as parallel universes intersect in the remembrances of times and people. In the process, there's reflection about whether one's happiness and sense of self-worth is rooted in one's company, sense of obligation toward others, and sturdiness of familiar walls that surround and protect.

This comedic-drama only strafes this psychological space. But in this way, the production displays a familiar Mint quality, most recently seen in its last show, Katie Roach, where a myriad of splendid ideas are postured about but detoured around in favor of focus on a basic story line.

This subtlety of production is very much Mint. In Autumn, we see a play of compelling simplicity that's a snapshot of a turning point in a family's life, a painting with small, intimate details set within the theatre's always attractive staging, brought to life by a solid cast and direction.

With likeable characters, splashes of humor, and occasional wit, that may be enough.
But with dialogue focused on housecleaning, cooking, the weather, caring for aging parents, suggested adultery, sibling rivalry, and shooting up the local wildlife, one can't help to wonder how quickly banality has replaced the trauma of war, of which the playwright was no doubt keenly aware.

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Wage Gap Tied To States' Minimum Wage And Latinas Most Affected By Pay Inequality, Study Says

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The fact that women’s wages lag behind men’s is nothing new, but a new report is showing that the minimum wage may have something to do with it.

According to a study by the National Women’s Law Center, the average gender wage gap in states with minimum wages above the federally mandated $7.25 per hour is smaller than the pay gap in states where the minimum wage meets the $7.25 criteria. Of the ten states with the widest wage gaps in 2011, only two had minimum wages above $7.25 per hour. All of the states with the narrowest wage gaps had minimum wages above the federally mandated level.

“The gap in wages has moved at a snail’s pace—shrinking only 18 cents in five decades and remaining stagnant for the last decade,” said NWLC Co-President Marcia D. Greenberger.  “And for women of color, the wage gap is even worse.  Equal pay is not an abstract principle for women and their families.”

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Atrial Fibrillation Could Spell Early Dementia, Study Finds

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By: Lauren Cox, LiveScience Contributor
Published: 06/05/2013 04:06 PM EDT on LiveScience

An irregular heartbeat may be a sign you're on the fast track to dementia, according to a new study.

While thinking and memory problems are common in the elderly, the study of more than 5,000 people over age 65 showed that those with the heart condition atrial fibrillation tend to suffer mental decline earlier than people without the heart condition.

The reason for the link is unclear, and the findings don't mean that everyone with atrial fibrillation will suffer earlier mental decline, said study researcher Evan Thacker, a statistician in the department of epidemiology at the University of Alabama at Birmingham. "One person who has atrial fibrillation may not have any memory or thinking problems at all."

But as a group, people in the study with atrial fibrillation reached the threshold where mental decline is considered to be dementia two years earlier than those without the heart condition, according to the study published today (June 5) in the journal Neurology.

A few points missed means many troubles

In people with atrial fibrillation, misfiring electrical signals cause an atypical heartbeat. The Centers for Disease Control and Prevalence estimated 2.66 million people in the U.S. had atrial fibrillation in 2010. But the CDC expects 12 million people will have it by 2050.

Thacker's study used data from the large Cardiovascular Health Study done in the 1990s. Participants had their heart health measured, and took two types of mental tests each year over the course of about seven years. The researchers excluded participants who had had a stroke or a previous diagnosis of atrial fibrillation, before the study's start.

One test, called the Modified Mini-Mental State Examination (3MSE), measures global thinking abilities on a 100-point scale. The 3MSE tests whether you know where you are and what day it is, your language skills, or if you can copy interlocking shapes from a piece of paper. The other test, called the Digit Symbol Substitution Test (DSST), measures quick-thinking and multitasking.

Researchers found that people who developed atrial fibrillation during the study began doing worse on both mental tests. The results showed that the average score of people ages 80 to 85 fell by 6.4 points on the 3MSE over the study period. But the average score of people with atrial fibrillation declined 10.3 points.

And a 5- or 10-point drop on either test can indicate a noticeable difference in everyday life. "They may notice problems in memory that are more serious than remembering where you put your keys," Thacker said.

"It could be not having a good enough memory to find your way home after shopping," he said. In more serious cases it could mean a person can't put together a meal, or manage finances.

Behind the heart-brain connection

The findings are important, said Dr. Allyson Zazulia, associate professor of neurology at the Washington University School of Medicine in St. Louis, because "both atrial fibrillation and dementia are, of course, huge problems in the elderly."

And the elderly will account for an ever-larger part of the U.S. population as baby boomers age. [7 Ways to Prevent Alzheimer's Disease]

Thacker's study couldn't explain how atrial fibrillation might be related to memory problems. And at present, doctors don't even know if treating atrial fibrillation would help or hurt a person's risk for dementia.

But doctors who treat both conditions said the connection makes sense. For one, dementia and atrial fibrillation share the same risk factors.

A person with high blood pressure and diabetes is automatically considered to be at a higher risk of both atrial fibrillation and dementia, said Dr. Shadi Kalantarian, research fellow of the Cardiac Arrhythmia Service at Massachusetts General Hospital. Thacker's finding could have been called a coincidence if he hadn't accounted for those risk factors, but he did, and the connection between atrial fibrillation and dementia remained.

One cause for the lower test scores could be the fact that an irregular heartbeat can lead to chronic blood flow problems, possibly lowering the amount of oxygen and nutrients available to the brain.

So-called "silent" strokes could be another explanation. "People with atrial fibrillation are more prone to forming blood clots in their atrium," Kalantarian said. A large blood clot that lodges in the brain will cause a noticeable stroke and, of course, noticeable brain damage. However, a person could suffer a series of mini 'silent' strokes and not even know it, Kalantarian said.

"The 'silent' means that you don't have the sudden signs of stroke, but they are clearly not truly silent, because they cause an insidious development of cognitive and gait impairment," said Zazulia, who also thought silent strokes could be behind the connection.

Incorporating brain imaging into future large, long-term studies could show whether silent strokes are to blame for earlier signs of dementia.

"If medical researchers could find the answer to that question of why this happens, then we could have something useful for patients," Thacker said.

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Poultry Worker Study Finds Alarming Rate Of Carpal Tunnel As USDA Considers Line Speedup

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WASHINGTON -- A recent government study of workers at a poultry plant in South Carolina determined that four out of 10 showed signs of the painful hand-and-arm condition known as carpal tunnel syndrome, a finding that raises fresh concerns about a federal proposal that would allow plants to speed up their slaughtering lines.

Poultry processing work is full of repetitive motion, and numerous reports have documented the job's health and safety hazards over the years. The recent study by the National Institute for Occupational Safety and Health (NIOSH) examined just one plant, but workplace health experts say it offers one of the most granular looks at how the job takes a toll on line workers -- and how faster line speeds, currently being considered by the U.S. Department of Agriculture, could possibly make things worse.

"This gives you a snapshot of what goes on in one plant," said Celeste Monforton, a public health expert at George Washington University. "It's done and it shows damning results. ... I don't know how USDA will dismiss what's in this."

NIOSH experts visited the plant twice last year, examining workers who eviscerate, debone and cut chickens to prepare them for sale, according to the report. They interviewed the workers about hand and arm pain and performed nerve conduction tests on them. Forty-two percent had indications of carpal tunnel, and a majority of workers reported "multiple musculoskeletal symptoms," most commonly hand and wrist pain.

Read the report below.

Out of 318 participants at the plant, 213 "reported pain, burning, numbness or tingling in their hands or wrists in the past 12 months." Furthermore, two-thirds of those 213 workers reported "awakening from sleep because of these symptoms."

Despite those findings, public health and labor advocates say these workers may soon see their workloads increase.

Last year, the USDA put forth a proposal to overhaul the poultry inspection process. The change would pull many government inspectors off the slaughtering line where they visually inspect birds, moving resources instead toward the detection of bacteria and other invisible dangers. The rule change would thereby allow poultry plants to speed up their slaughtering lines, delivering savings to poultry companies.

Backers have pitched the proposal as a cost-saver for both government and industry. Critics, however, have called it a giveaway to the poultry business that could have unintended consequences.

Many occupational health experts have objected to the proposal, saying line speeds already move too fast for workers like those in the South Carolina plant that NIOSH visited. USDA officials have told stakeholders privately that the change wouldn't impact line workers, drawing a distinction between the slaughtering process, where the speedup would occur, and the processing line, where most workers toil.

But critics like Tony Corbo, a lobbyist at the watchdog group Food & Water Watch, say that if chickens are being slaughtered at a faster rate, then it stands to reason they will be processed at a faster rate as well. Corbo told HuffPost he's skeptical that poultry plants, well-known for their tight controls on labor costs, will be eager to add more workers to the lines to account for a slaughtering speedup. Many plant employees already work essentially shoulder-to-shoulder, he noted.

"If you're speeding up the lines, guess what -- it's going to impact the speed at which those workers are chopping up the chickens," Corbo said. "Unless they establish new lines in the factories, those workers are going to be working faster and faster.

"Remember Lucy in the candy factory?" he added.

Poultry line workers are among some of the most vulnerable laborers in the U.S. The polyglot workforces often include immigrants from Latin American and African countries, who generally work for low pay on demanding production schedules. Class-action lawsuits have become common in the industry, with workers claiming they're shorted on their wages or required to work off the clock.

The NIOSH study was done at the request of the Agriculture Department, and the South Carolina plant was required to undergo the evaluation in order to secure a waiver under the current line-speed rules. A NIOSH spokeswoman said experts will evaluate the workers again after the speedup to determine what, if any, the health effects have been. Those results will be shared with the USDA as well.

An Agriculture Department spokeswoman said the agency "welcomes NIOSH's work" and is reviewing the study's findings.

"This data is preliminary," she said in an email. "We look forward to the full results of NIOSH’s research and to working with them further on this issue."

The agency wouldn't be required to alter or scrap the speed-up proposal based on any health findings, and it isn't clear what bearing NIOSH's studies will have on the final rule. As Monforton and others noted, the White House and the USDA appear committed to moving forward with the rule.

The president's most recent budget proposal assumes the rule will go into effect -- an assumption that the left-leaning Center for Progressive Reform calls a "rebuke" to concerned parties.

"The President’s budget suggests that most of these concerns, raised by a broad coalition of the public interest community, have been ignored in a headlong rush to finalize a rule that officials believe will save a few million dollars," the group wrote. "Yet, some hope remains that the rule is not written in stone."

Read the NIOSH report here.

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Union Membership Decline Boosts Corporate Profit At Workers' Expense, Study Says

Corporate profit has been soaring for years at workers' expense and a decline in union membership is to blame -- not a rise in technology, a new study found.

The jump in corporate profit over the past few decades can be explained largely by a decline in union membership over the same period, according to a study by Tali Kristal, a sociologist at the University of Haifa in Israel. The boost in companies’ bottom line comes at workers’ expense, Kristal wrote in an email to The Huffington Post.

“It’s a zero sum game: whatever is not going to workers, goes to corporations,” Kristal said. “Union decline not only increased wage gaps among workers, but also enabled capitalists to grab a larger slice of the national income pie at the expense of all workers, including the highly skilled.”

The findings, published Thursday in the American Sociological Review, add a new dimension to the debate over income inequality in the U.S., suggesting that policies aimed at boosting unions may help. Corporate profit soared to a record high share of the economy earlier this year, according to Bloomberg, while workers' wages have remained largely stagnant. The rise in profit comes as union membership has dropped to a record low.

Kristal’s findings contradict claims that increased computerization largely accounts for the boost in corporate profit at the expense of workers. Kristal argued that the rise of machines is only indirectly to blame, because technology has reduced union workers by replacing some union jobs with automation, directly increasing corporate profit.

“If we want all workers to benefit from the economic growth, then policymakers can initiate some steps to strengthen unions, such as pro-union reforms of labor law, and deterioration with employers' illegal anti-union tactics that increasingly spread over the last decades,” Kristal wrote.

Indeed, other analyses, including one from the left-leaning Economic Policy Institute, have found that that the drop in union membership in recent decades correlates with the rise in inequality during the same period.

“The decline in union members is directly related to the stagnation of wages for working people,” Brandon Rees, acting director of the Office of Investment at the AFL-CIO, an umbrella labor organization for many unions, told HuffPost. “Economic growth has been going somewhere and its been going to the top 1 percent.”

That dynamic could be problematic for the U.S. economy as a whole, Rees said, as middle-class Americans burdened by debt and slow wage growth buy less and hold back the recovery.

“One of the reasons why we are suffering from anemic growth today is because consumers have been reducing their debt levels, but wages are not keeping up with productivity growth,” Reese said. “The rights of workers to join a union has helped create the middle class in this country and the middle class has been hammered in the past 20 years as unions have declined.”

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