Monthly Archive for June 2009

Risk assessment of pesticide exposure on health of tobacco farmers

Tobacco is an important cash crop of Pakistan. Pesticides are commonly used to increase the crop yield, but their health impact has not been studied yet.  

Tobacco Farmer exposed to toxic PesticidesThe objectives of the study were to determine the frequency of pesticide poisoning and to explore the knowledge, attitudes and practices (KAP) towards safety measures among the tobacco farmers in Swabi, Pakistan.  

One hundred and five tobacco farmers involved in pesticide application were randomly selected from two villages of district Swabi. A structured questionnaire was used for clinical and KAP information. Plasma cholinesterase (PChE) levels were measured by Ellman’s method by using GD Italy kits. All tobacco farmers were males with a mean (SD) age of 26 (9) years.  

The majority of the farmers reported multiple symptoms headache, dizziness, vomiting, shortness of breath, muscle weakness and skin rash correlate with the clinically significant depression of PChE levels. 

Out of 105 pesticide applicators, 58 (55%) had post-exposure reduction in PChE levels <20% from baseline, 35 (33%) had mild poisoning (20-40% reduction) and 12 (11%) had moderate poisoning (>40% reduction).  

Most of the farmers did not use any personal protective equipment during pesticide handling. Only a few used shoes (31%), masks (14%) and gloves (9%) during pesticide spray.  

In conclusion, the tobacco farmers had mild to moderate pesticide poisoning, which was correlated with depression in PChE levels. Moreover, most farmers had little knowledge about the safety measures, casual attitude and unsatisfactory safety practices with regard to the use of basic protective equipments during pesticide applications on the tobacco crop. 

Reference: Khan DA, Shabbir S, Majid M, Naqvi TA, Khan FA., Risk assessment of pesticide exposure on health of Pakistani tobacco farmers, aDepartment of Pathology, Army Medical College, NUST, Rawalpindi, Pakistan, Journal of Exposure Science and Environmental Epidemiology advance online publication, 17 June 2009; doi:10.1038/jes.2009.13.

Association to household gas appliances with cognition and attention behavior in children

Gas Stove is dangerous for the Health of Children

The authors investigated the association of early-life exposure to indoor air pollution with neuropsychological development in preschoolers and assessed whether this association differs by glutathione-S-transferase gene (GSTP1) polymorphisms. A prospective, population-based birth cohort was set up in Menorca, Spain, in 1997-1999 (n = 482).

Children were assessed for cognitive functioning (McCarthy Scales of Children’s Abilities) and attention-hyperactivity behaviors (Diagnostic and Statistical Manual of Mental Disorders, 4th Edition) at age 4 years.

During the first 3 months of life, information about gas appliances at home and indoor nitrogen dioxide concentration was collected at each participant’s home (n = 398, 83%). Genotyping was conducted for the GSTP1 coding variant Ile105Val. Use of gas appliances was inversely associated with cognitive outcomes (beta coefficient for general cognition = -5.10, 95% confidence interval (CI): -9.92, -0.28; odds ratio for inattention symptoms = 3.59, 95% CI: 1.14, 11.33), independent of social class and other confounders.

Nitrogen dioxide concentrations were associated with cognitive function (a decrease of 0.27 point per 1 ppb, 95% CI: -0.48, -0.07) and inattention symptoms (odds ratio = 1.06, 95% CI: 1.01, 1.12).

The deleterious effect of indoor pollution from gas appliances on neuropsychological outcomes was stronger in children with the GSTP1 Val-105 allele. Early-life exposure to air pollution from indoor gas appliances may be negatively associated with neuropsychological development through the first 4 years of life, particularly among genetically susceptible children.

Reference: Morales E, Julvez J, Torrent M, de Cid R, Guxens M, Bustamante M, Künzli N, Sunyer J., Association of early-life exposure to household gas appliances and indoor nitrogen dioxide with cognition and attention behavior in preschoolers, Center for Research in Environmental Epidemiology, Barcelona, Catalonia, Spain, Am J Epidemiol. 2009 Jun 1;169(11):1327-36.

Study shows: Athletes, spectators faced unprecedented air pollution at 2008 Olympic Games

beijing-smog-at-olympics

Particulate air pollution during the 2008 Olympic Games in Beijing constantly exceeded levels considered excessive by the WHO – World Health Organization, was far worse than other recent Olympic Games, and was about 30 percent higher than has been reported by Chinese environmental experts – even though some favorable weather conditions helped reduce the problem. 

The weather, in fact, turned out to be more valuable in addressing this concern than major programs by the Chinese government to heavily restrict automobile use, close factories and slow construction during and before the Olympic games. 

These findings are among the final results just published in Environmental Science and Technology, a professional journal, in the first comprehensive study of particulate air pollutants in Beijing and how they compared to past Olympics. 

The research was done before, during and after the 2008 Olympics by scientists from Oregon State University and Peking University, in work funded by the National Science Foundation in the United States and the National Science Foundation of China. 

“Considering the massive efforts by China to reduce air pollution in and around Beijing during the Olympics, this was the largest scale atmospheric pollution experiment ever conducted,” said Staci Simonich, an OSU associate professor of environmental and molecular toxicology. “Despite all that, it was some evening rains and favorable shifts in the winds that provided the most relief from the pollution. 

“This demonstrates how difficult it is to solve environmental problems on a short-term, local basis,” she added. 

And despite some favorable weather and the pollution control efforts, researchers said, the end result was some of the most severe particulate pollution that Olympic athletes have dealt with in recent games. The levels were about two to four times higher than that of Los Angeles on an average day. 

In some of the first comparisons of these type ever made, scientists determined that particulate matter air pollution in the Beijing Olympics were about double the levels of recent games in Athens, Greece; triple those of Atlanta, Ga.; and 3.5 times higher than the games in Sydney, Australia. However, the study also noted that, because of its control efforts, Beijing had the most significant decrease in particular air pollution compared to the other Olympic sites around the time of their games. 

Despite these efforts, levels of coarse particular matter were higher than considered safe by the World Health Organization 81 percent of the time during the Beijing Olympics. They reached unacceptable levels 100 percent of the time for the most dangerous particulate matter (smaller than 2.5 microns), which is more easily inhaled into the lungs and causes more serious health problems. Levels of the smaller, most harmful particulate matter was also the least affected by government efforts to reduce pollution output, the study concluded.

 The finding of levels of pollution higher than those announced previously by Chinese officials reflects a difference in measurement methodology, researchers said, although the approaches used in this study have been widely accepted for many years. 

The studies were initially prompted due to traditionally high levels of air pollution in Beijing and the potential risk they posed to athletes and spectators, Simonich said. The city of 17 million people is surrounded by mountains in several directions that trap air pollutants, and has faced significant increases in particulate air pollution in recent years due to increasing industrialization, numbers of automobiles, coal and biomass burning, and other causes. 

Atmospheric particulate matter, researchers say, is a concern because various sized particles have potentially toxic chemicals “sorbed” to them. The fine particles have been linked to increased respiratory morbidity and mortality. In China, particulate matter air pollution is believed to be responsible for about one million premature deaths per year, researchers said in their study. 

Of some note, the scientists said, is that efforts taken to constrain air pollution may be having a lasting value – particulate matter air pollution in Beijing was as much as 27 percent lower last fall than in the same months a year earlier. Some of this, however, may have been attributable to lower levels of industrial and economic activity. 

Simonich said that there is no scientific evidence so far of any health problems that have been linked to the short-term exposure of athletes or spectators to this pollution during the Olympic competition. 

“The athletes and visitors were only exposed for a very short time,” Simonich said. “Millions of other people there face this air quality problem their entire lives. It was unlike anything I’ve ever seen – you could look directly at the sun and not have a problem, due to the thickness of the haze.” 

Reference: Oregon State University, Athletes, spectators faced unprecedented air pollution at 2008 Olympic Games, CORVALLIS, Oregon, June 19, 2009

Fibromyalgia Patients Show Decreases In Gray Matter Intensity

Previous studies have shown that fibromyalgia is associated with reductions in gray matter in parts of the brain, but the exact cause is not known. Using sophisticated brain imaging techniques, researchers from Louisiana State University, writing in The Journal of Pain, found that alterations in levels of the neurotransmitter dopamine might be responsible for gray matter reductions.

For the study, magnetic imaging resonance data from 30 female fibromyalgia patients were compared with 20 healthy women of the same age. The primary objective of the study was to confirm original findings about reduced gray matter density in a larger sample of fibromyalgia patients. They explored whether there is a correlation between dopamine metabolic activity and variations in the density of gray matter in specific brain regions.

Results showed there were significant gray matter reductions in the fibromyalgia patients, which supports previous research. In addition, the fibromyalgia patients showed a strong correlation of dopamine metabolism levels and gray matter density in parts of the brain in which dopamine controls neurological activity.

The authors concluded that the connection between dopamine levels and gray matter density provide novel insights to a possible mechanism that explains some of the abnormal brain morphology associated with fibromyalgia.

Reference: American Pain Society (2009, June 18). Fibromyalgia Patients Show Decreases In Gray Matter Intensity. ScienceDaily. Retrieved June 19, 2009

New online tool links government food test results to pesticide toxicology science

food-chemicals

Searchable database shows pesticide residues still common

San Francisco, June 17, 2009 — Ever wonder about pesticides on your food? Or in your drinking water? In particular, which of those pesticides are most hazardous? A new tool from the nonprofit group Pesticide Action Network sheds new science-driven light on the invisible problem of pesticide residues.
 
Today’s launch of the What’s on My Food? database makes the results of government tests for pesticide residues in food available online in a searchable, easy-to-use format. The database shows what pesticides are found on each food, in what amount, and – for the first time – links those residues to the health effects associated with exposure to each of the chemicals.
 
“This kind of public visibility around pesticides is particularly needed in the U.S.,  since regulators base their decisions on toxicology studies that are almost all done by industry,” explains Dr. Brian Hill, Senior Scientist with Pesticide Action Network and the primary developer of the What’s on My Food? database. “Nearly 900 million pounds of pesticides are used in the U.S. every year, yet regulations depend on studies that are not peer-reviewed and are kept hidden behind the veil of ‘confidential business information.’” Hill notes that the 900 million figure is long overdue for updating, as the most recent pesticide use figures from the Environmental Protection Agency are for 2001.
 
In addition to highlighting the potential direct health effects of pesticide residues, the What’s on My Food? database points to the many problems associated with pesticide use before food reaches the kitchen table. Widespread use of agricultural chemicals threatens the health of workers and those in nearby communities and schools, as well as harming wildlife and contaminating ecosystems, according to the site.
 
“It’s time to shift away from reliance on these dangerous chemicals,” says Kathryn Gilje, Pesticide Action Network’s Executive Director. “In Europe governments have recognized that a healthy population and clean environment are worth more than short-term industry profits. They are moving toward safer and healthier ways to produce food, and we need to do the same.”
 
In the Take Action section of the site, Pesticide Action Network calls on consumers not only to vote with their dollars by choosing organic foods whenever possible, but also to become involved as “food citizens” demanding a clean, green and fair food production system.
 
Launch of the new database coincides with the release of Food, Inc., a film by the producers of An Inconvenient Truth that documents the dangerous health and environmental impacts of industrialized food production. Food reporter Michael Pollan calls Food, Inc. “the most important and powerful film about our food system in a generation.”
 

Reference: Pesticide Action Network North America, Searchable database shows pesticide residues still common, June 18, 2009

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