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The controversy over the safety of BPA (bisphenol A) is still dragging on. However, the new alternatives to BPA may not be any better and may be even worse. To minimize exposure to BPA and other estrogenic chemicals, try to buy and store food in glass bottles, jars, and containers (glass does not contain plastics of any sort). The following two articles discuss this issue. From Nature:

Toxicology: The plastics puzzle

A stroll down the aisles of a US supermarket reveals a modest victory for consumer activism. In the baby-products section, plastic baby bottles, spill-proof cups and miniature cutlery are proudly marked 'BPA-free' — a sign that they no longer contain the compound bisphenol A, found in many plastics.

The partial withdrawal of BPA is the culmination of two decades of research and hundreds of studies linking the compound — which mimics sex hormones called oestrogens — to adverse health effects in rodents and humans.  The decision by regulators in the United States and European Union to ban BPA from baby bottles, combined with industry marketing campaigns, has convinced many consumers that the plastics and other containers currently used to store food are safe.

It is a false sense of security. BPA is still a constituent of many food containers, especially cans. And when companies did abandon BPA, they often adopted compounds — such as the increasingly common bisphenol S (BPS) — that share much of the same chemistry and raise many of the same concerns as BPA. “People use this chemical to replace BPA without sufficient toxicological information,” says Kyungho Choi, an environmental toxicologist at Seoul National University. “That is a problem.”

BPA has formed the chemical backbone of most hard, clear polycarbonate plastic since the 1950s. Over time, studies have linked the chemical — which can leach out of plastics and into food — to a host of adverse health effects, including reductions in fertility and birth weight, male genital abnormalities, altered behavioural development, diabetes, heart disease and obesity1 (see Nature46411221124; 2010).

A few years ago, mounting evidence and concerned consumers convinced governments to take action. In 2011, the European Union banned BPA from baby bottles; the United States followed suit a year later. But BPA-based linings are still slathered on the insides of most food and beverage cans, and used to coat water-supply pipes in many countries. The compound is also found in dental sealants and in incubators for premature infants.

BPA-based epoxy linings are widely used because they are strong, flexible and cheap. They tolerate the high temperatures needed to sterilize foods during canning, and do not interact with a huge array of foods and beverages, according to the North American Metal Packaging Alliance in Washington DC. The alliance estimates that 95% of all aluminium and steel can coatings are epoxy-type resins: more than 99.9% of these contain BPA.

New options are beginning to surface. BPS was first made in 1869 as a dye. But because it was introduced into consumer goods only recently — into cash-register receipts in 2006, for example — few researchers have studied its toxicity. “The main question, to which we have no answer, is: 'is BPS as toxic as BPA?'” says René Habert, an endocrinologist at Paris Diderot University.

The similarity of BPS's structure to that of BPA is enough to raise suspicions that it may mimic oestrogens, says Cheryl Watson, a biochemist at the University of Texas Medical Branch in Galveston. When combined with levels of oestradiol found in adult women, BPS seemed to over-stimulate the pathway, shutting it down and causing cell suicide. The results, says Watson, were typical of those expected of an oestrogen mimic: inappropriate activation of oestrogen responses, disruption of normal oestrogen-response pathways, and eventual cell death. 

Some manufacturers have left the bisphenol family in search of a replacement. In 2007, the Eastman Chemical Company launched Tritan — a new heat-resistant clear plastic — for infant-care products such as baby bottles. This BPA-free plastic has since replaced the old BPA-containing polycarbonate in many water bottles, food containers and children's cups. 

In 2011, George Bittner, a neurobiologist at the University of Texas at Austin and the chief executive of Austin-based chemical-testing company CertiChem, reported that 92% of 102 commercially available plastic products leached chemicals with oestrogenic activity7. This included plastics advertised as BPA-free. The reason, Bittner says, is that additives in plastics — such as stabilizers and lubricants — can also bind to oestrogen receptors, as can some of the plastic monomers themselves. Tritan resins produced by Eastman were among the polymers that showed oestrogenic activity in Bittner's assays. 

In 2012, the world produced some 280 million tonnes of plastic. According to a model based on the United Nations' Globally Harmonized System of Classification and Labelling of Chemicals, more than 50% of these plastics contain ingredients that can be hazardous (see Nature 494169171; 2013). Some are carcinogenic; others are oestrogenic.

It is not yet clear how many of these chemicals are dangerous at the concentrations found in the plastics. But mixed together, the chemicals could have synergistic effects

Ideally, says Watson, the next generation of chemicals would be tested for effects on oestrogen signalling before widespread deployment in food containers.

From Mother Jones:

The Scary New Evidence on BPA-Free Plastics

An excellent reason to listen to your mother and eat your vegetables. From the U.S. Department of Health and Human Services site healthfinder.gov:

Vegetables in Childhood May Benefit Breast Health

Girls who ate the most fruits and vegetables rich in carotenoids were less likely to get benign breast disease, a new study suggests.

Carotenoids are a group of pigments that typically produce an orange, red or dark green color. They are believed to have antioxidant properties that may guard against disease. Benign breast disease describes a variety of noncancerous conditions of the breast; some forms raise the risk of breast cancer. 

For her study, Boeke and her colleagues looked at food reports from 1996 through 1998 and then evaluated reports in 2005, 2007 and 2010 from girls who got a diagnosis of benign breast disease from a doctor after having a biopsy. In all, Boeke studied nearly 6,600 girls, and 122 reported a diagnosis of benign breast disease.

When she looked at carotenoid intake, she found high intakes were protective. "The odds of benign breast disease in those who consumed the most beta carotene were about half that of those who consumed the least," she said. Girls in the highest intake group ate two to three servings of carotenoid-rich foods weekly, she said.

She did take into account other factors that might affect the risk of benign breast disease, such as alcohol intake, physical activity, family history and body mass index (a measure of body fat using height and weight).

Why might the fruits and vegetables help? It's not known for sure, but Boeke said it may be due partly to their antioxidant properties. Carotenoids absorb harmful substances known as free radicals which can harm cells.

The study looked only at food intake, not supplements, and Boeke said she would not recommend supplements since other research has found some harmful effects with supplement use. Other foods that are rich in carotenoids include yams, melons, spinach and kale.

The period of time between the start of a girl's period and the first birth is a sensitive one for the breasts, as they are very vulnerable to environmental exposures, according to background information in the study.

Paternal age of 25 to 29 at conception resulted in the lowest risk of adult-onset hormone related cancers in their daughters. From Science Daily:

Father's age at birth may affect daughter's cancer risk

Paternal age and the health effects it has on potential offspring have been the focus of many studies, but few have examined the effect parental age has on the risk of adult-onset hormone-related cancers (breast cancer, ovarian cancer and endometrial cancer).

A team of City of Hope researchers, lead by Yani Lu, Ph.D., explored this relationship and found that a parent’s age at birth, particularly a father’s age, may affect the adult-onset cancer risk for daughters — especially for breast cancer.

“Our findings indicate that parental age, especially paternal age, at conception appears to be associated with a wide range of effects on the health and development of the offspring,” Lu said.

To help determine the effects of parental age on the risk of adult-onset hormone-related cancers, Lu and her colleagues examined a cohort of 133,479 female teachers and administrators from the California Teachers Study. Between 1995 and 2010, 5,359 women were diagnosed with breast cancer, 515 women were diagnosed with ovarian cancer and 1,110 women were diagnosed with endometrial cancer.

While the team of researchers did not find an association for maternal age at birth for any type of cancer, they found that paternal age is linked to an increased adult-onset cancer risk for daughters – and the link was not only to advanced paternal age.

Women born to a father under the age of 20 had a 35 percent greater risk of breast cancer and more than two times greater risk of ovarian cancer, when compared to those born to a father whose age at his daughter’s birth was 25 to 29 years old.

Women born to a father whose age at childbirth was 30 to 34 years had a 25 percent greater risk of endometrial cancer than those born to a father age 25 to 29.

Lu and her team were not surprised to find a relationship between older fathers and an increased risk of hormone-related cancers, especially since there has been increasing evidence suggesting that daughters born to older fathers have increased risk of breast cancer, noted Lu.

“We observed that young paternal age, as well as advanced paternal age, increase the risk of breast cancer,” said Lu. “We also found that young paternal age increases the risk of ovarian cancer.”

This is a depressing research finding, with long-term negative results. From Science Daily:

Four in 10 infants lack strong parental attachments

In a study of 14,000 U.S. children, 40 percent lack strong emotional bonds -- what psychologists call "secure attachment" -- with their parents that are crucial to success later in life, according to a new report. The researchers found that these children are more likely to face educational and behavioral problems.

In a report published by Sutton Trust, a London-based institute that has published more than 140 research papers on education and social mobility, researchers from Princeton University, Columbia University, the London School of Economics and Political Science and the University of Bristol found that infants under the age of three who do not form strong bonds with their mothers or fathers are more likely to be aggressive, defiant and hyperactive as adults. These bonds, or secure attachments, are formed through early parental care, such as picking up a child when he or she cries or holding and reassuring a child.

Written by Moullin, Jane Waldfogel from Columbia University and the London School of Economics and Political Science and Elizabeth Washbrook from the University of Bristol, the report uses data collected by the Early Childhood Longitudinal Study, a nationally representative U.S. study of 14,000 children born in 2001. The researchers also reviewed more than 100 academic studies.

Their analysis shows that about 60 percent of children develop strong attachments to their parents, which are formed through simple actions, such as holding a baby lovingly and responding to the baby's needs. Such actions support children's social and emotional development, which, in turn, strengthens their cognitive development, the researchers write. These children are more likely to be resilient to poverty, family instability, parental stress and depression. Additionally, if boys growing up in poverty have strong parental attachments, they are two and a half times less likely to display behavior problems at school.

The approximately 40 percent who lack secure attachments, on the other hand, are more likely to have poorer language and behavior before entering school. This effect continues throughout the children's lives, and such children are more likely to leave school without further education, employment or training, the researchers write. Among children growing up in poverty, poor parental care and insecure attachment before age four strongly predicted a failure to complete school. Of the 40 percent who lack secure attachments, 25 percent avoid their parents when they are upset (because their parents are ignoring their needs), and 15 percent resist their parents because their parents cause them distress.

Susan Campbell, a professor of psychology at the University of Pittsburgh who studies social and emotional development in young children and infants, said insecure attachments emerge when primary caregivers are not "tuned in" to their infant's social signals, especially their cries of distress during infancy.

"When helpless infants learn early that their cries will be responded to, they also learn that their needs will be met, and they are likely to form a secure attachment to their parents," Campbell said. "However, when caregivers are overwhelmed because of their own difficulties, infants are more likely to learn that the world is not a safe place -- leading them to become needy, frustrated, withdrawn or disorganized."

The report, which is titled "Baby Bonds: Parenting, attachment and a secure base for children," was published March 21 by the Sutton Trust and is available online: http://www.suttontrust.com/our-work/research/item/baby-bonds/.

First researchers talked about second-hand cigarette smoke, but now there is a concern with third-hand smoke. From Science Daily:

Major 'third-hand smoke' compound causes DNA damage and potentially cancer

Leftover cigarette smoke that clings to walls and furniture is a smelly nuisance, but now research suggests that it could pose a far more serious threat, especially to young children who put toys and other smoke-affected items into their mouths. Scientists reported today that one compound from this "third-hand smoke," which forms when second-hand smoke reacts with indoor air, damages DNA and clings to it in a way that could potentially cause cancer.

Bo Hang, Ph.D., who presented the research, said that although the idea of third-hand smoke made its debut in research circles just a few years ago in 2009, evidence already strongly suggests it could threaten human health.

"The best argument for instituting a ban on smoking indoors is actually third-hand smoke," said Hang, a scientist at Lawrence Berkeley National Laboratory (LBNL).

Researchers have found that many of the more than 4,000 compounds in second-hand smoke, which wafts through the air as a cigarette is smoked, can linger indoors long after a cigarette is stubbed out. Based on studies led by Hugo Destaillats, also at LBNL, these substances can go on to react with indoor pollutants such as ozone and nitrous acid, creating brand-new compounds, some of which may be carcinogenic.

One of those compounds goes by the acronym NNA. Hang's research has shown that NNA, a tobacco-specific nitrosamine, locks onto DNA to form a bulky adduct (a piece of DNA bound to a cancer-causing chemical), as well as other adducts, in lab test tubes. Other large compounds that attach to DNA tend to cause genetic mutations. NNA also breaks the DNA about as often as a related compound called NNK, which is a well-studied byproduct of nicotine and a known potent carcinogen. This kind of DNA damage can lead to uncontrolled cell growth and the formation of cancerous tumors.

The biggest potential health risk is for babies and toddlers, he noted. As they crawl and put their hands or toys in their mouths, they could touch, swallow or inhale compounds from third-hand smoke. Their small size and early developmental stage make them more vulnerable than adults to the effects of environmental hazards.

Although many public places prohibit smoking, Hang noted that people can still smoke in most rental apartments and private residences -- and smoking remains a huge public health issue. In 2011, nearly 44 million American adults reported smoking cigarettes, which ranks as the leading cause of preventable death in this country. And 34 million people smoke every day, according to data from the Centers for Disease Control & Prevention.

So far, the best way to get rid of third-hand smoke is by removing affected items, such as sofas and carpeting, as well as sealing and repainting walls, and sometimes even replacing contaminated wallboard, he explained. Replacing furniture can be pricey, but Hang said vacuuming and washing clothes, curtains and bedding can also help.

This is really an important finding. For a while now many scientists have thought there was an environmental exposure (such as pesticides) link to autism. From Science Daily:

Autism, intellectual disability incidence linked with environmental factors

An analysis of 100 million US medical records reveals that autism and intellectual disability (ID) rates are correlated at the county level with incidence of genital malformations in newborn males, an indicator of possible congenital exposure to harmful environmental factors such as pesticides.

Autism rates -- after adjustment for gender, ethnic, socioeconomic and geopolitical factors -- jump by 283 percent for every one percent increase in frequency of malformations in a county. Intellectual disability rates increase 94 percent. Slight increases in autism and ID rates are also seen in wealthier and more urban counties.

The study, published by scientists from the University of Chicago March 13 in PLOS Computational Biology, confirms the dramatic effect of diagnostic standards. Incidence rates for Autism and ID on a per-person basis decrease by roughly 99 percent in states with stronger regulations on diagnosis of these disorders.

"Autism appears to be strongly correlated with rate of congenital malformations of the genitals in males across the country," said study author Andrey Rzhetsky, PhD, professor of genetic medicine and human genetics at the University of Chicago. "This gives an indicator of environmental load and the effect is surprisingly strong."

Although autism and intellectual disability have genetic components, environmental causes are thought to play a role. To identify potential environmental links, Rzhetsky and his team analyzed an insurance claims dataset that covered nearly one third of the US population. They used congenital malformations of the reproductive system in males as an indicator of parental exposure to toxins.

Male fetuses are particularly sensitive to toxins such as environmental lead, sex hormone analogs, medications and other synthetic molecules. Parental exposure to these toxins is thought explain a large portion of congenital reproductive malformations, such as micropenis, hypospadias (urethra on underside of the penis), undescended testicles and others.

The researchers created a statistical baseline frequency of autism and ID across the country. They then looked at the actual rates of these disorders, county-by-county. Deviations from the baseline are interpreted as resulting from local causes. Factors such as age, ethnicity, socioeconomic groups and geopolitical statuses were analyzed and corrected for.

The team found that every one percent increase in malformations in a county was associated with a 283 percent increase in autism and 94 percent increase in ID in that same county. Almost all areas with higher rates of autism also had higher rates of ID, which the researchers believe corroborates the presence of environmental factors. In addition, they found that male children with autism are almost six times more likely to have congenital genital malformations. Female incidence was linked with increased malformation rates, but weakly so. A county-by-county map of autism and ID incidence above or below the predicted baseline for the entire US is included in the study.

Non-reproductive congenital malformations and viral infections in males were also associated with double digit increases in autism and ID rates. Additionally, income appeared to have a weak effect -- every additional $1,000 of income above county average was correlated with around a three percent increase in autism and ID rates. An increased percentage of urban population in a county also showed a weak increase in rates.

Head lice is a big, big concern for parents of young school age children. From Science Daily:

Ordinary conditioner removes head lice eggs as effectively as special products

Eggs from head lice, also called nits, are incredibly difficult to remove. Female lice lay eggs directly onto strands of hair, and they cement them in place with a glue-like substance, making them hard to get rid of. In fact, the eggs are glued down so strongly that they will stay in place even after hair has been treated with pediculicides -- substances used to kill lice.

Some shampoos and conditioners that contain chemicals or special oils are marketed as nit-removal products. However, new research just published in the Journal of Medical Entomology shows that ordinary hair conditioner is just as effective.

In an article called "Efficacy of Products to Remove Eggs of Pediculus humanus capitis (Phthiraptera: Pediculidae) From the Human Hair," scientists from Belgium gathered 605 hairs from six different children. Each hair had a single nit attached to it. Approximately 14% of the eggshells contained a dead egg, whereas the rest were empty.

They then tried to remove the eggs and tested the amount of force needed to do so. They found that nits on the hairs that were left completely untreated were the most difficult to remove. Eggs on hairs that had been soaked in deionized water were much easier to remove, as were the eggs on hairs that had been treated with ordinary hair conditioner and with products specifically marketed for the purpose of nit removal.

However, they found no significant differences between the ordinary conditioners and the special nit-removal products. In all cases, less force was required to remove the nits after the hair had been treated, but the effectiveness of the products was essentially the same.

The authors hypothesize that the deionized water was effective because it acts as a lubricant, so less friction is needed to remove the nits from the hairs. The same goes for the conditioners.

From NPR:

More Hints That Dad's Age At Conception Helps Shape A Child's Brain

Traditionally, research has focused on women's "biological clock." But in recent years, scientists have been looking more and more at how the father's age at conception might affect the baby, too. A study published Wednesday hints that age really might matter — in terms of the child's mental health.

Researchers from the University of Indiana and the Karolinska Institute found that compared with children fathered by men who were 20-24 years old, kids born to dads who were 45 or older were three times as likely to have autism and 13 times as likely to have ADHD. Kids born to older dads were also more likely to go on to develop substance abuse problems and get lower grades in school. The findings appear in JAMA Psychiatry.

To figure out how paternal age was related to children's psychiatric health, the researchers looked at millions of parents in Sweden who had children between 1973 and 2001. The researchers took into account the mother's age, as well as other demographic factors that might play a role in the child's cognitive development and mental health.

"There's a growing body of literature that suggests that advancing paternal age is associated with a host of problems," D'Onofrio tells Shots. Another study, published in JAMA Psychiatrylast month, found that the children of older fathers seemed to be at greater risk for developing schizophrenia and autism.

D'Onofrio and his colleagues paid special attention to siblings and cousins, and found that even among kids in the same extended family, a dad's age when his child was born made a difference.

The results are in line with a growing body of research linking older fatherhood with various developmental problems in children.

However, the study looks only at how paternal age and children's mental health are associated — it's a correlation, Reichenberg cautions, not a proven causal link. Scientists haven't yet determined the mechanisms of the effect. But it doesn't seem to be simply a matter of overdiagnosis among the children of older parents, the scientists say. Other research has found that as men get older, their sperm cells are more likely to contain random mutations that might, theoretically, contribute to disorders like autism in their kids.

Ultimately, men and women of all ages, he says, should remember that age is only one of many factors influencing the developing baby's health.

"The most important thing is [that] future mothers and fathers should still go ahead and have children, even if the father is older than 45 or 50," Reichenberg says. "Most of these children will be absolutely fine."

Acetaminophen was the one nonprescription medication that for decades pregnant women thought was safe to take. Looks like not any more - a study found that taking acetaminophen during pregnancy was associated with hyperkinetic disorder and ADHD at age 7. And the longer it was taken during pregnancy, the stronger the association. From Science Daily:

Use of acetaminophen during pregnancy linked to ADHD in children, researchers say

Acetaminophen, found in over-the-counter products such as Excedrin and Tylenol, provides many people with relief from headaches and sore muscles. When used appropriately, it is considered mostly harmless. Over recent decades, the drug, which has been marketed since the 1950s, has become the medication most commonly used by pregnant women for fevers and pain.

In a report in the current online edition of JAMA Pediatrics,researchers from the UCLA Fielding School of Public Health show that taking acetaminophen during pregnancy is associated with a higher risk in children of attention-deficity/hyperactivity disorder and hyperkinetic disorder. The data raises the question of whether the drug should be considered safe for use by pregnant women.

ADHD, one of the most common neurobehavioral disorders worldwide, is characterized by inattention, hyperactivity, increased impulsivity, and motivational and emotional dysregulation. Hyperkinetic disorder is a particularly severe form of ADHD.

The UCLA researchers used the Danish National Birth Cohort, a nationwide study of pregnancies and children, to examine pregnancy complications and diseases in offspring as a function of factors operating in early life. The cohort focuses especially on the side effects of medications and infections. The researchers studied 64,322 children and mothers who were enrolled in the Danish cohort from 1996 to 2002. 

More than half of all the mothers reported using acetaminophen while pregnant. The researchers found that children whose mothers used acetaminophen during pregnancy were at a 13 percent to 37 percent higher risk of later receiving a hospital diagnosis of hyperkinetic disorder, being treated with ADHD medications or having ADHD-like behaviors at age 7. The longer acetaminophen was taken -- that is, into the second and third trimesters -- the stronger the associations. The risks for hyperkinetic disorder/ADHD in children were elevated 50 percent or more when the mothers had used the common painkiller for more than 20 weeks in pregnancy.

"It's known from animal data that acetaminophen is a hormone disruptor, and abnormal hormonal exposures in pregnancy may influence fetal brain development," Ritz said. Acetaminophen can cross the placental barrier, Ritz noted, and it is plausible that acetaminophen may interrupt fetal brain development by interfering with maternal hormones or through neurotoxicity, such as the induction of oxidative stress, which can cause the death of neurons.

From Science Daily:

Impact of repetitive heading in soccer needs more research, say experts

Soccer is the most-popular and fastest-growing sport in the world and, like many contact sports, players are at risk of suffering concussions from collisions on the field. But researchers warned in a paper published today that not enough attention has been given to the unique aspect of soccer -- the purposeful use of the head to control the ball -- and the long-term consequences of repetitive heading.

The literature review by Dr. Tom Schweizer, director of the Neuroscience Research Program of St. Michael's Hospital, was published in the journal Brain Injury.

More than 265 million people play soccer worldwide, including 27 million in North America. Due to the nature of the sport, players are particularly vulnerable to head and neck injuries. Most are caused by unintentional or unexpected contact, such as when a player collides with teammates, opponents or the playing surface.

There is significant concern in the sporting and medical worlds about the potential long-term cognitive and behavioral consequences for athletes who suffer acute or repeat concussions or multiple "sub-concussive" head impacts -- blows to the head not causing symptoms of concussions.

"The practice of heading, which might occur thousands of times over a player's career, carries unknown risks, but may uniquely contribute to cognitive decline or impairment in the short- or long-term," said Dr. Schweizer, a neuroscientist. "Thus, soccer players present a unique opportunity to study whether cumulative sub-concussive impacts affect cognitive functioning, similar to that of concussions."

Research papers that looked at the mechanism of injury found 41.1 per cent of concussions resulted from contact by an elbow, arm or hand to the head. One found that 58.3 per cent of concussions occurred during a heading duel. More females suffered concussions from player-to-surface and player-to-ball contact than males who had more player-to-player contact than females.

Studies on the long-term effects of heading found greater memory, planning and perceptual deficits in forwards and defenders, players who execute more headers. One study found professional players reporting the highest prevalence of heading during their careers did poorest in tests of verbal and visual memory as well as attention. Another found older or retired soccer players were significantly impaired in conceptual thinking, reaction time and concentration. The few studies that used advanced imaging techniques found physical changes to the brains in players who had concussions.