Low-level mercury exposure in pregnant women connected to ADHD risk in children
Posted by Xeno on October 8, 2012
Attention-deficit/hyperactivity disorder ADHD affects approximately ten percent of children worldwide, yet its causes are not well understood. Now, a study led by Susan Korrick, MD, MPH, of Brigham and Women’s Hospital BWH, and Sharon Sagiv, PhD, MPH, of Boston University School of Public Health, and published in the online version of the Archives of Pediatrics & Adolescent Medicine on October 8, 2012, links low-level prenatal mercury exposure with a greater risk of ADHD-related behaviors. The study also finds that maternal fish consumption during pregnancy can help reduce the risk of ADHD-related behaviors in children. This duality is possible because many types of fish have low levels of mercury, so it is possible for a pregnant woman to eat nutritionally beneficial fish without being exposed to much mercury.”These findings underscore the difficulties pregnant women face when trying to balance the nutritional benefits of fish intake with the potential detriments of low-level mercury exposure,” said Dr. Korrick.Dr. Sagiv agrees this study provides an important public health message, saying, “Women need to know that nutrients in fish are good for the brain of a developing fetus, but women need to be aware that high mercury levels in some fish pose a risk.”This analysis involved approximately 400 children born in New Bedford, Massachusetts between 1993 and 1998. Shortly after their mothers gave birth, researchers collected hair samples from the mothers and analyzed them for mercury. They also gave the mothers a questionnaire to determine their fish consumption during pregnancy. Eight years later, researchers followed up with the children and administered standardized tests to determine behaviors related to ADHD.Researchers found an increased risk of childhood ADHD-related behaviors with increasing maternal hair mercury levels. These mercury levels were lower than levels shown to be potentially hazardous in most previous studies. Additionally, researchers found a reduced risk of ADHD-related behaviors in children whose mothers reported eating more than two servings of fish per week, which is a higher number of servings than is currently recommended by the United States Food and Drug Administration and Environmental Protection Agency.The study did not examine what types of fish are best for a pregnant woman to eat, but previous studies have shown women should avoid fish that are high in mercury, such as shark, swordfish, king mackerel and fresh tuna. Fish that are low in mercury, such as flounder, haddock, and salmon, are safer to eat and good sources of nutrition.
Alkali and metal processing, incineration of coal, and medical and other waste, and mining of gold and mercury contribute greatly to mercury concentrations in some areas, but atmospheric deposition is the dominant source of mercury over most of the landscape. Once in the atmosphere, mercury is widely disseminated and can circulate for years, accounting for its wide-spread distribution. Natural sources of atmospheric mercury include volcanoes, geologic deposits of mercury, and volatilization from the ocean. Although all rocks, sediments, water, and soils naturally contain small but varying amounts of mercury, scientists have found some local mineral occurrences and thermal springs that are naturally high in mercury. …
In highly polluted areas where mercury has accumulated through industrial or mining activities, natural processes may bury, dilute, or erode the mercury deposits, resulting in declines in concentration. In many relatively pristine areas, however, mercury concentrations have actually increased because atmospheric deposition has increased. For instance, concentrations of mercury in feathers of fish-eating seabirds from the northeastern Atlantic Ocean have steadily increased for more than a century. In North American sediment cores, sediments deposited since industrialization have mercury concentrations about 3-5 times those found in older sediments. Some sites may have become methylmercury hot spots inadvertently through human activities. Lake acidification, addition of substances like sulfur that stimulate methylation, and mobilization of mercury in soils in newly flooded reservoirs or constructed wetlands have been shown to increase the likelihood that mercury will become a problem in fish. Although scientists from USGS and elsewhere are beginning to unravel the complex interactions between mercury and the environment, a lack of information on the sources, behavior, and effects of mercury in the environment has impeded identification of effective management responses to the Nation’s growing mercury problem.
Warnings about mercury in fish and seafood have gotten plenty of attention in recent years. But where does all that mercury come from in the first place? Apparently, the largest sources of mercury emissions into our air and water are going all but unnoticed. A new study published in the Journal of Environmental Monitoring has found that mercury in the atmosphere is an oft-ignored form of air pollution, especially in urban areas where concentrations can reach dangerously high levels. The U.S. Environmental Protection Agency (EPA) has been lax in its enforcement of mercury-pollution standards over the past decade, exempting major polluters. Mercury is a neurotoxin that can harm the developing brains of children and infants; in adults, exposure can lead to memory loss and affect fertility and blood pressure.
Here are the biggest emitters of mercury into the environment:
1. Coal-fired power plants. Mercury exists naturally in coal, making coal-fired power plants the largest source of mercury pollution in this country. Coal accounts for nearly 50 percent of the electricity generated in this country—and almost 50 tons of mercury emissions annually. …
2. Cement kilns. According to the nonprofit law firm Earthjustice, all the cement kilns in the U.S. combined pump out roughly 23,000 pounds of mercury every year. The mercury comes from coal, which is used to fuel the cement-manufacturing process, as well as limestone, another natural source of the heavy metal. The group released a report last July finding that, individually, some cement kilns emit nearly one and a half times more mercury than the most polluting coal-fired power plants. But because there are fewer kilns, they account for lower levels of atmospheric mercury overall than coal plants. …
3. Chlor-alkali plants. Chlorine bleach, laundry detergent, cheap vinyl purses, shoes, and toys made with polyvinyl chloride (or PVC)—making all these products required the use of chlorine gas at some point. The chlor-alkali plants that produce it use mercury to convert salt to chlorine gas, and to convert salt to caustic soda, or lye, which is then used in products like detergent, plastics, and bleach. The nonprofit Natural Resources Defense Council (NRDC) says that while most modern chlor-alkali plants have switched to mercury-free technology, there are still seven plants in the U.S. that use it, and each one has roughly 200 tons of mercury on site at any given time. An unknown amount of that mercury gets lost during manufacturing, whether to the air or surrounding waterways; a 2006 report from NRDC found that operators at four of these plants could account for only 29 of the 159 tons of the mercury they used from 2000 to 2004. (As Rodale.com reported earlier this year, some of those plants also make the ubiquitous food ingredient high-fructose corn syrup, and may be tainting food products with mercury.) …
4. Trash incinerators. Hazardous waste, medical waste, and regular garbage incinerators release 13.1 tons (or about 26,000 pounds) of mercury every year, according to statistics from the EPA. The mercury comes from common household items, such as compact fluorescent light bulbs and thermostats, and from automobile scrap. Despite common perceptions that mercury is used in thermometers and blood pressure machines, the medical industry has switched to mercury-free versions of those tools, and medical waste now accounts for the smallest percentage of mercury emissions from incinerators. …
via hwww.rodale.com (Click for more, including what you can do about it.)
Get your mercury containing fillings replaced by a dentist who specializes in their safe removal. Your health may greatly improve in a month or so if you do. However, I’m not sure there are any completely safe options yet. Do you have BPA-based dental fillings?
A new study finds that children who have their cavities filled with a white composite resin known as bis-GMA appear to develop small but quantifiable drops in psychosocial function. To put it simply: Treated kids can become more moody, aggressive and generally less well adjusted.
Bis-GMA is hardly a household name, although its starting ingredient — bisphenol A — is. An estrogen-mimicking compound, BPA is best known as a building block of some clear plastics, food-contact resins and inks used for store receipts.
The new report, posted online July 16 in Pediatrics, is “very important,” says Philip Landrigan, director of the Children’s Environmental Health Center at Mount Sinai School of Medicine in New York City. These data linking bis-GMA and behavioral changes in kids “make a strong case that in the short term, use of BPA-containing dental materials should be minimized,” he says. Over the longer term, he argues, manufacturers should look to discontinue the materials’ use in children as soon as acceptable substitutes are readily available.
In the new study, researchers followed more than 400 youngsters with cavities after each received his or her first-ever fillings. Throughout the next 5 years, the scientists linked a subtle drop in behavioral scores to cavities that had been filled with a composite material made from bis-GMA.
The numerical change in behavioral scores was small, roughly 2 to 6 points on a 100-point scale (where a score of 50 is average). Parents might not notice a change that small or could easily attribute it to other factors. But that doesn’t mean the magnitude was trivial, argues Nancy Maserejian of New England Research Institutes in Watertown, Mass., who led the study.
A 1- or 2-point drop in IQ is similarly small. But if it occurred across a broad swath of a huge population, even such a tiny change would prove costly. Each 1 point drop in IQ will diminish an individual’s lifetime earnings potential — and even, potentially, boost community costs for education and dealing with behavioral and learning problems. Similarly, each drop of a few points in neurobehavioral measures effectively shifts huge numbers of children below the threshold of being able to effectively manage stress, anger, disappointment and relationships with family and others, Maserejian notes.
Stay away from Resin ionomers. They release fluoride into the tooth, which means into your bloodstream because teeth have many small holes and are connected inside to your blood circulation. What we need is a dental filling made of the same stuff teeth are made of, right? Wikipedia says:
… Enamel does not contain collagen, as found in other hard tissues such as dentin and bone, but it does contain two unique classes of proteins – amelogenins and enamelins. While the role of these proteins is not fully understood, it is believed that they aid in the development of enamel by serving as a framework for minerals to form on, among other functions. Once it is mature, enamel is almost totally absent of the softer organic matter. Enamel is avascular and has no nerve supply within it and is not renewed, however, it is not a static tissue as it can undergo mineralization changes.
What you want is your teeth to patched with the same stuff that used to be there before they had a cavity. I’ve seen one paper on using hydroxyapatite (HA) as a dental restorative material. Very interesting!