Residential Pesticides Linked to Childhood Brain Cancer

Children who live in homes where parents use pesticides are twice as likely to develop brain cancer, according to the results of a new study published in the journal Environmental Health Perspectives. The study evaluated more than 800 fathers and more than 500 mothers that live in residential areas in four Atlantic Coast states in order to better understand the science behind the cause of childhood brain cancers.

The parents' exposure to various pesticides at home and at the workplace was assessed through computer-assisted telephone interviews with the mothers. The researchers analyzed intensity and probability of exposure levels based on information on residential pesticide use and jobs held by the fathers during the 2 years before the child's birth.

"Parental exposures may act before the child's conception, during gestation, or after birth to increase the risk of cancer," wrote the study's authors. "Before conception, exposures may cause mutations or epigenetic alterations in gene expression... in the sperm or egg."

According to the researchers, previous studies have suggested association between childhood brain cancers and parental pesticide use. Those associative links are what motivated this more extensive study that involved participants in Florida, New Jersey, New York (excluding New York City) and Pennsylvania. New York City was excluded "because the unique characteristics of the city make tracing cases and identifying controls very difficult."

A significant risk of astrocytoma was associated with herbicide exposure from residential use. Astrocytomas are cancers of the brain that originate in star-shaped brain cells called astrocytes. Primitive neuroectodermal tumors (PNET) were not associated with any of the pesticide classes or exposure sources considered. Thus, the researchers conclude that the results of this study are consistent with previous studies associating parental pesticide exposures to childhood brain cancer.

Significantly, according to the study's report, the risk of childhood cancer was dramatically reduced for children of fathers who washed immediately after any pesticide exposure, or who wore protective clothing.

Data for the study were obtained from the mothers through the telephone interviews during a 13-month period between 2000 and 2001. These included details on lawn and garden care and specifics on job industries for the working parents in the household.

Potential effects from four ranges of pesticide were evaluated. These were insecticides, herbicides, agricultural fungicides, and nonagricultural fungicides. "Nonagricultural fungicides" refers to disinfectants, germicides, and similar chemicals used to control bacteria.

More than 1,200 jobs for fathers, and about 1,000 jobs for mothers were assessed for exposure probabilities and levels. Other factors that were considered included the mothers' education levels.

Parental exposure to pesticides at the workplace was significantly less common than for residential pesticide exposure.

According to the report, the United States Environmental Protection Agency (EPA) has classified many pesticides as "probable or likely human carcinogens" while others are categorized as "suggestive or possible carcinogens." -NaturalNews

Type Of Plankton -- Food Source For Many Fish -- Has Ability To Survive Climate Change

Queen's researchers have found that the main source of food for many fish - including cod - in the North Atlantic appears to adapt in order to survive climate change.

Billions of Calanus finmarchicus, a plankton species, which are just a few millimetres in size, live in the waters of the North Atlantic where the research was carried out.

It showed they responded to global warming after the last Ice Age, around 18,000 years ago, by moving north and maintaining large population sizes and also suggests that these animals might be able to track the current change in habitat.

The effect of global climate change on the planet's ecosystems is one of the key issues scientists are currently focussing on and the research has been published in Proceedings of the Royal Society B, a publication of the national academy of science of the UK and the Commonwealth, today.

One of the main predicted effects of climate change is a forced shift in species' distribution range.

The study leader, Dr Jim Provan, from Queen's School of Biological Sciences, said the discovery that that a species has a feature which helps it cope with global warming is a rare example of good news.

"Our results, in contrast to previous studies, suggest that the species has been able to shift its distribution range in response to previous changes in the Earth's climate, and thus 'track' the effects of climate change, a feature which may be of crucial importance in its survival.

"The genetic variability of the species - the tendency of the genetic make-up of a population to vary from one individual to another - has remained high, which is good news, and suggests that these animals might be able to track the current change in habitat resulting from global warming and maintain viable population sizes.

"If the species couldn't, it might become extinct and thus threaten the fish species that depend upon it for food.

"It might be a rare example of news that may not be doom-and-gloom with respect to climate change, but it doesn't mean that we don't have to keep watching what happens."

Previous work on the species had indicated a serious drop in numbers and decreases in population size may be reflected in decreases in genetic variability.

This can compromise the adaptive potential of the populations for the future and possibly result in extinction.

As a result of the Queen's findings the team is planning further work to see how the study applies to rapid global warming over the last few decades. -ScienceDaily

Pollution Effects

Pollutants can cause disease, including cancer, lupus, immune diseases, allergies, and asthma. Higher levels of background radiation have led to an increased incidence of cancer and mortality associated with it worldwide. Some illnesses are named for the places where specific pollutants were first formally implicated. One example is Minamata disease, which is caused by organic mercury compounds.

Adverse air quality can kill many organisms including humans. Ozone pollution can cause respiratory disease, cardiovascular disease, throat inflammation, chest pain and congestion. Water pollution causes approximately 14,000 deaths per day, mostly due to contamination of drinking water by untreated sewage in developing countries. Oil spills can cause skin irritations and rashes. Noise pollution induces hearing loss, high blood pressure, stress and sleep disturbance. -M. Saqib Ansari

Fire Influences Global Warming More Than Previously Thought

Fire's potent and pervasive effects on ecosystems and on many Earth processes, including climate change, have been underestimated, according to a new report.
"We've estimated that deforestation due to burning by humans is contributing about one-fifth of the human-caused greenhouse effect -- and that percentage could become larger," said co-author Thomas W. Swetnam of The University of Arizona in Tucson.

"It's very clear that fire is a primary catalyst of global climate change," said Swetnam, director of UA's Laboratory of Tree-Ring Research.

"The paper is a call to arms to earth scientists to investigate and better evaluate the role of fire in the Earth system," he said.

The team also reports that all fires combined release an amount of carbon dioxide into the atmosphere equal to 50 percent of that coming from the combustion of fossil fuels.

"Fires are obviously one of the major responses to climate change, but fires are not only a response -- they feed back to warming, which feeds more fires," Swetnam said.

When vegetation burns, the resulting release of stored carbon increases global warming. The more fires, the more carbon dioxide released, the more warming -- and the more warming, the more fires.

The very fine soot, known as black carbon, that is released into the atmosphere by fires also contributes to warming.

"The scary bit is that, because of the feedbacks and other uncertainties, we could be way underestimating the role of fire in driving future climate change," Swetnam said.

The report's 22 authors call for the Intergovernmental Panel on Climate Change, or IPCC, to recognize the overarching role of fire in global climate change and to incorporate fire better into future models and reports about climate change.

David Bowman, a lead co-author, said, "We're most concerned that fire has not been rigorously and adequately incorporated in the climate models. It's remarkable that such an integral part of the landscape has been so sidelined."

Swetnam, Bowman of the University of Tasmania in Hobart, Australia, the other lead co-author Jennifer K. Balch of the National Center for Ecological Analysis and Synthesis in Santa Barbara, Calif. and their colleagues will publish their paper, "Fire in the Earth System," in the April 24 issue of the journal Science. A complete list of authors is at the end of this release.

Because fire on Earth predates humans, its ubiquitous activity is simultaneously accepted and overlooked. Bowman says, "Fire is extraordinarily obvious, but deeply subtle."

The article ties together various threads of knowledge about fire from disparate fields including ecology, global modeling, physics, anthropology, environmental history, medicine and climatology.

A more complete understanding of how the Earth works requires recognizing how fire is intertwined with and also a driver of human history and the Earth's history, the authors write.

Balch said of the article, "This synthesis is a prerequisite for adaptation to the apparent recent intensification of fire feedbacks, which have been exacerbated by climate change, rapid land-cover transformation, and exotic species introductions."

She commented about "fires where we don't normally see fires," and pointed to the occurrence of bigger and more frequent fires from the western U.S. to the tropics.

Swetnam said that, in addition to the burning in the tropics, huge tracts of the boreal forests of Siberia, Canada and northern Europe burn each year.

"The role of fire in forests in the boreal zone is unappreciated," he said.

"Russian forests alone contain more than 50 percent of the carbon stored on land in the Northern Hemisphere," Swetnam wrote in an e-mail, adding that warming is happening fastest at high latitudes.

In some recent years, the acreage burned in the forests of Siberia exceeded the size of the U.S. state of Virginia, he said. As the world warms, more of those regions are likely to burn, accelerating the warming.

Calling for a holistic fire science, Balch said, "We don't think about fires correctly."

"Fire is as elemental as air or water. We live on a fire planet. We are a fire species. Yet, the study of fire has been very fragmented. We know lots about the carbon cycle, the nitrogen cycle, but we know very little about the fire cycle, or how fire cycles through the biosphere." -ScienceDaily