all Department of Environmental Health stories

Ingenious use of indigenous tree reaps award

50443248 — Tue, 02 Oct 2007 12:38:17 -0400

The jatropha tree is a humble — some might even say homely — plant, with large, maple-like leaves and clusters of inedible fruit that, when mature, look too brown and shriveled to be of much use to anyone. But to thousands of rural eastern and southern Africans, the jatropha is a beautiful thing. It represents hope that they’ll someday have electric lamps to light their homes, refrigerators to keep medicines and vaccines cold in local clinics, and computers and telephones in the schools and orphanages — hope for sustainable energy. And on Tuesday (May 8), the people behind that hope were honored with the 2007 Roy Family Environmental Award in a day of events at the Kennedy School of Government (KSG).

Dust from Asia invades North America

70652986 — Mon, 26 Mar 2007 06:28:24 -0400

On the dustiest days in the western United States, 40 percent of the grime blows in from Asia. And fine particles can travel all the way around the world from Africa's Sahara Desert. These unwanted visitors show up in a new model of dust imports developed by researchers from Harvard and the National Aeronautics and Space Administration (NASA). The findings have important implications for air pollution and climate change.

The Asian dust invasion is heaviest in the western states in spring. It moves on into the eastern U.S., but in much lower quantities. The traveling grime is mobilized by strong winds blowing over deserts or dry lakes and streambeds. "Most of the dust is from natural sources and falls out close to its source," notes Daniel Jacob, a professor of atmospheric chemistry and environmental engineering at Harvard. "But fine dust can be transported over long distances: from Asia to North America, and from North Africa to Florida, and all the way around the world to Canada and the U.S."

The grit is a health problem. A study done by other investigators, at the Harvard School of Public Health, concludes that an increase of particulate air pollution increases the risk of early death for people with diabetes, chronic obstructive lung disease, congestive heart failure, and inflammatory ailments like rheumatoid arthritis and lupus. Fine mineral dust is so damaging because it can penetrate much deeper into the lungs than larger particles.

Jacob worked with graduate student T. Duncan Fairlie and research associate Rokjin Park to build a computer model for estimating the impact of dust from Asia. They tested the model's accuracy with measurements from a NASA aircraft mission over the Pacific led by Jacob in 2001. The results were compared with dust records from Japan, various Pacific Islands, and air quality observing stations in the United States.

The model simulates the highs and lows of dust flow. Following the largest flow in spring, things quiet down in summer. Then a second, less active peak blows dust around in the fall. Winter is quiet.

North African dust imports peak during summer months in Florida and along the Gulf Coast. It adds haze in the Great Smoky Mountains, the Appalachians, and other East Coast locations.

Mold, mold everywhere

70652986 — Mon, 26 Mar 2007 06:24:56 -0400

Mold has attacked what remains of New Orleans, engulfing the city in slime. Typically, clean indoor environments show mold spore concentrations of less than 1,000 per cubic meter of air. But in Katrina's wake, the numbers have hit several million due to widespread, persistent flooding.

That's the preliminary report from Christine Rogers, a senior research scientist in the Department of Environmental Health at Harvard School of Public Health. In September, Rogers led a hands-on investigation of mold contamination so extensive that the health hazards are unknown.

"Our fear was that city residents returning home might experience massive exposures, simply by retrieving belongings and doing minor cleanups," she says.

Tapped by the National Institute of Environmental Health Sciences (NIEHS) Center at Harvard to come up with recommendations as part of a national NIEHS working group, Rogers had searched the literature. But she could find no data applicable to the situation in New Orleans, where water has stood motionless in closed-up buildings, several feet deep, for weeks.

What Rogers' team found amazed them: Wall-to-wall mold colonies. "It was biological warfare, with all these fungi fighting for space," Rogers says.

Holding their breath for the breathless

70652986 — Mon, 26 Mar 2007 05:40:49 -0400

Two researchers at the Harvard School of Public Health (HSPH) got the idea of studying free divers to get information that would help them help the breathless to breathe better. "We hope that by studying these athletes, we can teach patients how to better cope and recover from episodes of breathlessness," says Andrew Binks.

Divers took a battery of tests to see why their breathing capacity is so different from that of other people. Both they and a comparison group of normals were hooked up to a mechanical ventilator that controlled how often and how deeply they breathed. This device prevented the divers from breathing faster and deeper than nondivers.

Walking improves cognitive functions in older women

70652986 — Mon, 26 Mar 2007 05:35:24 -0400

In a study, elderly women who engaged in the most activity -- for example, walking at least 6 hours per week -- had a 20 percent decrease in risk of cognitive impairment compared to those who were inactive. they also demonstrated the cognitive functioning of someone three-years younger than their actual age. The findings were published in the Sept. 22, 2004, issue of the Journal of the American Medical Association. “Walking is a popular, accessible and inexpensive activity for older adults that appears to provide many health benefits. In addition to studies showing a reduced risk of heart disease, pulmonary disease and diabetes, a moderate level of walking also appeared to reduce the rate of cognitive decline in our study,” said lead author Jennifer Weuve of the Harvard School of Public Health. “What is most striking is that for older women who are able to engage in several hours per week of physical activity, their cognitive function seemed to be comparable to that of a woman several years younger.” Researchers analyzed the data from 18,766 U.S. women, aged 70 to 81 years, from the Nurses' Health Study.

Climate, asthma connected, according to research

70652986 — Mon, 26 Mar 2007 05:30:54 -0400

Christine Rogers, a research associate at the Harvard School of Public Health, measures particulates - pollen grains and fungal spores - in outdoor air and correlates levels with asthma events. She also examines how those particulate levels might change over time because of global warming. "One of the most predictable effects of global warming is that CO2 is going to increase," she says. "But also, seasonality is going to change. Springs will come earlier, lengthening our growing seasons. Both of these trends affect plants' biomass, making them larger at maturity and, logically, able to produce more pollen." To measure the effects of global warming on pollen production, Rogers and her colleagues forced ragweed plants to germinate two and four weeks earlier than they normally would, simulating the early springs that are likely to become more frequent. Half of each plant group was exposed to the normal, ambient CO2 level of 350 parts per million, and the other half to double that amount. Rogers found that total pollen production under ambient CO2 was higher in the plants grown in early spring than in those grown later. At high CO2 levels, however, plants grown later had higher total pollen production than those at ambient CO2.

Researcher studies effects of terrorist attacks on office workers near WTC site

70652986 — Mon, 26 Mar 2007 05:22:12 -0400

Since 1971, the National Institute for Occupational Safety and Health has conducted 1,200 investigations into indoor air. Last fall, the agency undertook an investigation unlike all the others. Aided by a Harvard School of Public Health scientist, Ashok Nimgade, a NIOSH research team evaluated the physical and mental health problems of office workers near "ground zero" of the World Trade Center attacks in New York City. The study revealed that workers who reported higher stress and depression levels were also more likely to report physical symptoms, such as coughing and skin irritations. The study also revealed that workers who expressed their feelings to confidantes were less likely to have physical complaints.

Professor honored for ongoing environmental research

70652986 — Mon, 26 Mar 2007 05:29:41 -0400

Harvard Professor Jack Spengler and MIT professor Mario Molina shared the $250,000 Heinz award, which recognized the independent bodies of work by Spengler and Molina, although coincidentally the researchers are collaborating on air quality studies in Mexico City. Spengler, Akira Yamaguchi Professor of Environmental Health and Human Habitation in the Department of Environmental Health at the Harvard School of Public Health, was recognized for his research as well as his advocacy efforts. "Dr. Spengler is a true scientific explorer, having charted, virtually by himself, an undiscovered environmental scourge -- indoor air pollution," said Teresa Heinz, chairman of the Heinz Family Foundation. "He has succeeded in focusing the nation's attention on a new insidious, invisible threat, one that had been silently and adversely affecting the nation's health. The technology that scientists rely on today for critical air pollution measurements would not have been possible without Dr. Spengler's pioneering work." Spengler is currently helping to lead the Healthy Public Housing Initiative, an endeavor to respond to high levels of asthma in low-income communities in Boston. He was co-editor of the Indoor Air Quality Handbook. Earlier in his career, he was a researcher with the groundbreaking Six Cities Studies, which explored the environmental risks associated with sulfur dioxide and particle emissions from coal-burning power plants. The studies found a lethal relationship between particulate matter and cardiovascular mortality.

Replacing joints early may be better than waiting for some osteoarthritis sufferers

70652986 — Mon, 26 Mar 2007 05:28:36 -0400

In a study, scientists from Brigham and Women's Hospital (BWH) and Toronto Western Hospital followed the progress of patients who opted to have joint replacement surgery. They found that those patients who had postponed having the surgery the longest -- and therefore were experiencing the most pain and loss of joint function -- also experienced the worst results two years after joint replacement surgery. "Many patients and doctors have traditionally regarded this kind of surgery as a last-resort sort of procedure," said the study's senior author, Jeffrey Katz of BWH. "But we found that patients could have a positive impact on their quality of life by being proactive about the real benefits associated with having this surgery before their conditions completely degenerate." In the study, 222 patients were divided into two groups: those with higher joint function and less pain, and those with more pain, and less joint function. Researchers noticed very little difference between how people felt after six months, compared to how they felt after two years. However, the patients who went into surgery feeling the worst, also felt worse than the healthier group two years after having their hips or knees replaced.

Study of phthalate exposure in humans finds association with sperm DNA damage

70652986 — Mon, 26 Mar 2007 05:27:19 -0400

Phthalates are a class of compounds used to hold color and scent in many cosmetics and personal care items such as soaps, detergents, skin preparations and aftershave lotions, and they also find their way into food through packaging materials. Di-ethylhexyl phthalate, one form of phthalate, is used to soften a wide range of plastic goods, which includes medical devices. Phthalates are also present in drinking water and air. Studies conducted by the Centers for Disease Control and Prevention found MEP in more than 75 percent of U.S. subjects sampled. Measurements were made of five different urinary phthalate metabolites, but only one yielded a significant association with sperm DNA damage, and that was MEP, which was found in all of the urine samples and at higher levels than the other metabolized phthalates. Researchers, led by Susan M. Duty and Russ Hauser of the Harvard School of Public Health, have termed the study preliminary, as it evaluated semen and a single urine sample from a limited number of subjects, just 168 men at an infertility clinic associated with the Vincent Memorial Obstetrics and Gynecology Service, Massachusetts General Hospital. The researchers plan follow-up studies with larger groups of men to confirm the results.

Boston bike messengers experience very high injury rate

70652986 — Mon, 26 Mar 2007 05:27:12 -0400

Bike couriers have become as a much a part of the urban landscape as sky-scrapers and traffic-clogged streets. Boston messengers collectively make between 3,000 and 4,000 deliveries on a given day. It may seem obvious that messengers work in dangerous conditions, quickly maneuvering around cars and pedestrians during peak congestion times. But little is known about the occupational hazards or rate and severity of injuries among this group because many bike messengers are independent contractors rather than employees of a courier service. As a result, injuries sustained on the job go unreported and days lost to injury are days without pay. To quantify the injuries, 113 bike couriers in Boston completed a two-page, self-administered injury survey in July 2001, that assessed total injuries and frequency, injury severity as well as individual characteristics, job characteristics and perceived risk. Only 32 percent of the participants reported having medical insurance. "The injury rate among bike couriers appears to be typical, if not higher, than those of professional football players who only work for part of the year," said study author Jack Tigh Dennerlein. The study appeared in the December 2002 issue of the American Journal of Industrial Medicine.

Battling toxic molds

70652986 — Mon, 26 Mar 2007 05:23:26 -0400

Molds are found in all kinds of environments. Estimates of the number of kinds of molds range from tens of thousands to more than 300,000, with more than 1,000 species known to typically grow indoors, according to the Centers for Disease Control and Prevention. While many molds appear to be benign to humans -- and some, such as the kind that produces penicillin, are beneficial -- several species are considered to be potent toxins. Questions raised by molds interest Mike Muilenberg, research associate and instructor in the Department of Environmental Health at Harvard's School of Public Health. As part of a series of studies on indoor allergens, Muilenberg is looking at the relationship between mold and health.

Maternal history influences risk of asthma in children exposed to cats

70652986 — Mon, 26 Mar 2007 05:24:51 -0400

Recent studies have gathered evidence that cat exposure during infancy can be protective against asthma. Research at Brigham and Women's Hospital confirmed these findings in all but one situation: when the child's mother has asthma. Researchers found that in a group of children with non-asthmatic mothers, those exposed to a cat were 40 percent less likely to experience persistent wheezing as compared to those with no cat exposure. Among children with a maternal history of asthma, the risk of wheezing associated with exposure to a cat increased with age.The findings suggest that children of asthmatic mothers become more readily sensitized to cat allergen and wheeze when exposed to it. "This research reinforces our knowledge that for the vast majority of children, having a cat in the home during their developmental years can be beneficial by protecting against asthma and allergies," said Juan Celedon, lead author of the study. "It is only among a high-risk group - children with a maternal history of asthma and perhaps, those whose mothers are allergic to cats - that exposure to a cat can negatively impact respiratory health." The study was supported by the National Institutes of Health.

Maternal bone lead levels pose toxic prenatal risk

70652986 — Mon, 26 Mar 2007 05:22:10 -0400

Although much attention has been paid to public health efforts to reduce lead exposure in children between the ages of six months and five years, when environmental lead exposures (such as from leaded paint in old houses) tend to be greatest, less attention has been paid to understanding the transfer of lead from mother to fetus and its resulting health effects. Now, Harvard researchers have concluded that elevated maternal bone lead levels are linked to impaired cognitive development in infants. Given the lengthy amount of time lead can reside in maternal bone and that bone is demineralized into the blood during pregnancy, the findings highlight a potentially significant public health problem, linking the history of a mother's lead exposure to risk for the next generation. The study appeared in the July 2002 issue of the journal Pediatrics. Howard Hu, principal investigator of the study, is associate professor at the Harvard School of Public Health. The study was supported by grants from the March of Dimes, National Institute of Environmental Health and Safety, US and Consejo National de Cienca y Technologia and CONSERVA, Department of Federal District, Mexico.

Harvard researchers take aim at asthma

70652986 — Mon, 26 Mar 2007 05:21:20 -0400

Asthma is one of the most common chronic conditions in America, afflicting about 15 million people and causing 5,000 deaths annually, according to the National Institutes of Health. Asthma rates have been on the increase, rising by 75 percent from the early 1980s to the mid-1990s. Asthma disproportionately affects children and African-Americans, and is especially prevalent in low-income populations. The prevalence of asthma in Boston's neighborhoods reflects national trends with higher rates in poorer neighborhoods. The rates of asthma hospitalization in Boston's Roxbury section between 1994 and 1997 were the highest in the city, about six to eight times that in wealthier Back Bay.