Chemicals in common consumer products may play a role in pre-term births : phthalates

2009 study posted for filing

Contact: Laura Bailey baileylm@umich.edu 734-647-1848 University of Michigan

ANN ARBOR, Mich.—A new study of expectant mothers suggests that a group of common environmental contaminants called phthalates, which are present in many industrial and consumer products including everyday personal care items, may contribute to the country’s alarming rise in premature births.

Researchers at the University of Michigan School of Public Health found that women who deliver prematurely have, on average, up to three times the phthalate level in their urine compared to women who carry to term.

Professors John Meeker, Rita Loch-Caruso and Howard Hu of the SPH Department of Environmental Health Sciences and collaborators from the National Institute of Public Health in Mexico and the U.S. Centers for Disease Control and Prevention analyzed data from a larger study directed by Hu, which follows a cohort of Mexican women recruited during pre-natal visits at one of four clinics of the Mexican Institute of Social Security in Mexico City.

Meeker and colleagues looked at data from 60 women: 30 who carried to term and 30 who delivered prematurely (defined as less than 37 weeks gestation). They analyzed urine samples collected during the third trimester and compared them to the control group who carried to term. They found significantly higher phthalate metabolite levels in the women who delivered prematurely.

Premature birth is a significant risk factor for many health problems in childhood that can persist into adulthood, Meeker says. In the United States, premature births have increased by more than 30 percent since 1981 and by 18 percent since 1990. In 2004, premature births accounted for 12.8 percent of live births nationwide.

Premature births, he says, account for one-third of infant deaths in the United States, making it the leading cause of neonatal mortality. Being born too early can also lead to chronic health problems such as blindness, deafness, cerebral palsy, low IQ and more.

Phthalates are commonly used compounds in plastics, personal care products, home furnishings (vinyl flooring, carpeting, paints, etc.) and many other consumer and industrial products. The toxicity varies by specific phthalates or their breakdown products, but past studies show that several phthalates cause reproductive and developmental toxicity in animals.

A couple of human studies have reported associations between phthalates and gestational age, but this is the first known study to look at the relationship between phthalates and premature births, Meeker says.

“We looked at these commonly used compounds found in consumer products based on the growing amount of animal toxicity data and since national human data show that a large proportion of the population are unknowingly exposed,” Meeker said. “One of the problems for consumers is that you don’t know exactly which products contain phthalates because the products do not have to be labeled accordingly.”

Meeker says the U-M study is a stepping stone to larger and more detailed studies examining the role of phthalates and premature births. The researchers hope to examine a larger population of pregnant women to corroborate these initial study findings, and conduct experimental lab studies to further explore the biological mechanisms of how phthalates work in the body.

###

 

The study, “Urinary Phthalate Metabolites in Relation to Preterm Birth in Mexico City,” is available online at: http://www.ehponline.org/docs/2009/0800522/abstract.html. It will appear in a later printed issue of Environmental Health Perspectives.

For more on Meeker: http://www.sph.umich.edu/iscr/faculty/profile.cfm?uniqname=meekerj

Loch-Caruso: http://www.sph.umich.edu/iscr/faculty/profile.cfm?uniqname=rlc

Hu: http://www.sph.umich.edu/iscr/faculty/profile.cfm?uniqname=howardhu

EHS: http://www.sph.umich.edu/ehs/

The University of Michigan School of Public Health has been working to promote health and prevent disease since 1941, and is consistently ranked among the top five public health schools in the nation

Plain soap as effective as antibacterial but without the risk – Triclosan no more effective a soap

Contact: Laura Bailey baileylm@umich.edu 734-647-1848 University of Michigan

ANN ARBOR, Mich.—Antibacterial soaps show no health benefits over plain soaps and, in fact, may render some common antibiotics less effective, says a University of Michigan public health professor.

In the first known comprehensive analysis of whether antibacterial soaps work better than plain soaps, Allison Aiello of the U-M School of Public Health and her team found that washing hands with an antibacterial soap was no more effective in preventing infectious illness than plain soap. Moreover, antibacterial soaps at formulations sold to the public do not remove any more bacteria from the hands during washing than plain soaps.

Because of the way the main active ingredient—triclosan—in many antibacterial soaps reacts in the cells, it may cause some bacteria to become resistant to commonly used drugs such as amoxicillin, the researchers say. These changes have not been detected at the population level, but e-coli bacteria bugs adapted in lab experiments showed resistance when exposed to as much as 0.1 percent wt/vol triclosan soap.

“What we are saying is that these e-coli could survive in the concentrations that we use in our (consumer formulated) antibacterial soaps,” Aiello said. “What it means for consumers is that we need to be aware of what’s in the products. The soaps containing triclosan used in the community setting are no more effective than plain soap at preventing infectious illness symptoms, as well as reducing bacteria on the hands.”

The study, “Consumer Antibacterial Soaps: Effective or Just Risky”” appears in the August edition of Clinical Infectious Diseases. The team looked at 27 studies conducted between 1980 and 2006, and found that soaps containing triclosan within the range of concentrations commonly used in the community setting (0.1 to 0.45 percent wt/vol) were no more effective than plain soaps. Triclosan is used in higher concentrations in hospitals and other clinical settings, and may be more effective at reducing illness and bacteria.

Triclosan works by targeting a biochemical pathway in the bacteria that allows the bacteria to keep its cell wall intact. Because of the way triclosan kills the bacteria, mutations can happen at the targeted site. Aiello says a mutation could mean that the triclosan can no longer get to the target site to kill the bacteria because the bacteria and the pathway have changed form.

The analysis concludes that government regulators should evaluate antibacterial product claims and advertising, and further studies are encouraged. The FDA does not formally regulate the levels of triclosan used in consumer products.

Other antiseptic products on the market contain different active ingredients, such as the alcohol in hand sanitizers or the bleach in some antibacterial household cleaners. Aiello’s team did not study those products and those ingredients are not at issue.

###

The University of Michigan School of Public Health has been working to promote health and prevent disease since 1941, and is consistently ranked among the top five schools in the country. Faculty and students in the school’s five academic departments and dozens of collaborative centers and institutes are forging new solutions to the complex health challenges of today, including chronic disease, health care quality and finance, emerging genetic technologies, climate change, socioeconomic inequalities and their impact on health, infectious disease, and the globalization of health. Whether making new discoveries in the lab or researching and educating in the field, U-M public health faculty, students and alumni are deployed around the globe to promote and protect our health.

For more information about Aiello, see: http://www.sph.umich.edu/iscr/faculty/profile.cfm?uniqname=aielloa

For more on the School of Public Health, see: http://www.sph.umich.edu

* Reposted for Filing

Just Low level cadmium exposure linked to lung disease – Tobacco Contaminant

ANN ARBOR, Mich.—New research suggests that cadmium is one of the critical ingredients causing emphysema, and even low-level exposure attained through second-hand smoke and other means may also increase the chance of developing lung disease.

The University of Michigan School of Public Health study suggests that higher cadmium levels in the body as much as double the risk of developing a pulmonary disease diagnosis such as emphysema or chronic bronchitis.

Though some studies have linked high levels of cadmium with decreased lung function in occupationally exposed workers, this is only the second known study to show that subjects with even slightly increased levels of cadmium had decreased lung function and the first known study to do so using repeated measures of lung function over time.

“The study suggests that the critical ingredient in smoking that may be causing emphysema is cadmium, a well-known contaminant of cigarette smoke,” said Howard Hu, professor at the U-M School of Public Health and principal investigator in the study. “The worry is if you are exposed to this (cadmium) through other sources you can also be at risk for emphysema.”

Non-smokers are exposed to cadmium when they eat contaminated foods or inhale second-hand smoke, as well as through a host of occupational exposures. Cadmium is a metal that is difficult for the body to dispel, Hu said, because kidneys tend to retain cadmium, and it recycles into the body.

Cadmium has received its share of media attention, and some consumer groups are concerned about cadmium in sludge and crop fertilizers. It is also widely used in batteriesĀ  and pigments.

“The big picture is, we keep learning more about the contributions of environmental toxins to the chronic diseases of aging for which we never suspected an environmental cause,” said Hu, who is also chair of the School of Public Health Department of Environmental Health Sciences and has an appointment with the Medical School.

The study looked at 96 men randomly selected from within the Normative Aging Study, a project that began in 1961 and includes approximately 2,280 healthy, male volunteers from Boston, Mass.

Researchers tested lung function using three different measures. Subjects with higher levels of urinary cadmium showed evidence of a reduced ability to exhale, irrespective of whether they smoked but with an effect that was greatest and clearest among current and former smokers.

The next step is a much larger, population-based study with more subjects and multiple measurements of cadmium exposure and lung function over time, Hu said.

“With a larger population we will be able to better disentangle the independent effects of cadmium and smoking, and whether dietary cadmium or other non-cigarette sources may also influence lung function,” Hu said.

###

 

Sung Kyun Park, research assistant professor in the U-M School of Public Health, was second author and supervised the analysis of data. The paper, “Association Between 24-hour Urinary Cadmium and Pulmonary Function Among Community-Exposed Men: The VA Normative Aging Study” is available at: http://www.ehponline.org/docs/2008/11265/abstract.html. It is scheduled for the September issue of the journal Environmental Health Perspectives.

For more on Hu, visit: http://www.ns.umich.edu/htdocs/public/experts/ExpDisplay.php?ExpID=1188

For more on the School of Public Health: http://www.sph.umich.edu/

The University of Michigan School of Public Health has been working to promote health and prevent disease since 1941, and is consistently ranked among the top five public health schools in the nation. Faculty and students in the school’s five academic departments and dozens of collaborative centers and initiatives are forging new solutions to the complex health challenges of today, including chronic disease, health care quality and finance, emerging genetic technologies, climate change, socioeconomic inequalities and their impact on health, infectious disease, and the globalization of health.

EDITORS: Listen and link to a podcast with Howard Hu at: http://www.ns.umich.edu/podcast/audio.php?id=392

Requested Repost :19 Aug 2008