California farmers feel more threatened by climate policy than they do by climate change, according to a new study from the University of California, Davis, says a September 10, 2013 news release from UC Davis, "Policies worry farmers more than climate change, says new study." The study, published in the journal Global Environmental Change, found that the greatest climate risk Yolo County farmers believe they face in the future is not drought, water shortages, or temperature changes, but government regulations. You can read the original study online. However, this view did not make them less likely to participate in government incentive programs that would help their climate adaptation and mitigation efforts.
“We found that the past matters,” explains lead author Meredith Niles, in the news release. Niles is a doctoral candidate in the Graduate Group in Ecology and Department of Environmental Science and Policy at UC Davis. “Farmers’ past perceptions of different environmental policies had a larger impact on their climate change beliefs and policy behaviors than their actual experience with climate change.”
Yolo County is a north Central Valley community that is home to UC Davis and a diverse mix of crops and livestock systems. More than 80 percent of land in Yolo County is devoted to agriculture.
UC Davis researchers analyzed 162 surveys returned by farmers and ranchers in 2011, and they conducted interviews with 11 farmers and two cooperative extension agents in 2010. In Yolo County, 54 percent of farmers responding to the survey accepted that climate change was occurring. Of these, only 35 percent believed humans play a role in climate change.
Farmers were asked about their attitudes toward four specific environmental policies: pesticide use reporting (implemented in 1990), rice straw burning regulations (1991), a water quality conditional waiver program (2003), and stationary diesel engine emission regulations (2007). Farmers who had negative past experiences with environmental policies — viewing them as too costly or time-consuming, for example — showed less belief in climate change.
Farmers also tended to view policies that had been around the longest more positively, indicating that perceptions can become more favorable over time
Several farmers viewed climate change as something in the far distant future, rather than as an immediate threat. They viewed the need to adapt to changing weather as a centuries-old, inherent part of farming.
The study quoted one farmer as saying: “For me, to be concerned about it [climate change] at my level and at my point, I don’t think it’s useful for me. I have other more important things that affect my business or my family that I want to spend time on versus something that could happen ten thousand years from now.”
Despite negative views toward regulations and a lack of concern over climate change, 48 percent of farmers said they would participate in a government incentive program for climate change mitigation and adaptation
“This shows that farmers are willing to overlook negative past perceptions if there are incentives offered for them,” Niles says in the news release. While Niles said more research is needed, she thinks farmers hold similar sentiments in other parts of the country and world. Strikingly similar results were found in a comparative study she conducted in New Zealand, where 51 percent of farmers believed in climate change and were far more concerned about risks associated with climate policy.
The results of the Yolo County study indicate that failure to consider farmers’ perceptions of climate change and climate policy is a missed opportunity for policymakers to engage with the agricultural community and gain support for climate change initiatives, Niles says in the news release. Doing so could also reduce the time lag present when farmers’ views of past policies affect how they respond to future environmental issues — in this study’s case, decades later.
“These policy perceptions really linger because they’ve had a big impact on agricultural communities,” Niles explains in the news release. “To give them a voice and engage them in the process from the outset hopefully will alleviate their concerns in some ways.” Funding for the study was provided by the California Energy Commission, the National Science Foundation’s Graduate Research Fellowships Program, and the NSF’s Integrative Graduate Education and Research Traineeship program. The study’s co-authors, both from UC Davis, include Mark Lubell, professor of Environmental Science and Policy, and Van Ryan Haden, postdoctoral scholar with the Agricultural Sustainability Institute. The study’s principal investigator was Louise Jackson, professor of Land, Air and Water Resources.
Dangers of triclosan in some hand soaps found by UC Davis researchers
Triclosan, an antibacterial chemical widely used in hand soaps and other personal-care products, hinders muscle contractions at a cellular level, slows swimming in fish and reduces muscular strength in mice, according to researchers at the University of California, Davis, and the University of Colorado. The findings appear online in the Proceedings of the National Academy of Sciences of the United States of America, reports an August 13, 2012 news release from UC Davis, "Chemical widely used in antibacterial hand soaps may impair muscle function."
“Triclosan is found in virtually everyone’s home and is pervasive in the environment,” said Isaac Pessah, professor and chair of the Department of Molecular Biosciences in the UC Davis School of Veterinary Medicine and principal investigator of the study. “These findings provide strong evidence that the chemical is of concern to both human and environmental health.”
Triclosan is commonly found in antibacterial personal-care products such as hand soaps as well as deodorants, mouthwashes, toothpaste, bedding, clothes, carpets, toys and trash bags. The U.S. Environmental Protection Agency in 1998 estimated that more than 1 million pounds of triclosan are produced annually in the United States, and that the chemical is detectable in waterways and aquatic organisms ranging from algae to fish to dolphins, as well as in human urine, blood and breast milk.
The investigators performed several experiments to evaluate the effects of triclosan on muscle activity, using doses similar to those that people and animals may be exposed to during everyday life.
In “test tube” experiments, triclosan impaired the ability of isolated heart muscle cells and skeletal muscle fibers to contract. Specifically, the team evaluated the effects of triclosan on molecular channels in muscle cells that control the flow of calcium ions, creating muscle contractions. Normally, electrical stimulation (“excitation”) of isolated muscle fibers under experimental conditions evokes a muscle contraction, a phenomenon known as “excitation-contraction coupling,” the fundamental basis of any muscle movement, including heartbeats. But in the presence of triclosan, the normal communication between two proteins that function as calcium channels was impaired, causing skeletal and cardiac muscle failure.
The team also found that triclosan impairs heart and skeletal muscle contractility in living animals. Anesthetized mice had up to a 25-percent reduction in heart function measures within 20 minutes of exposure to the chemical.
Effects of triclosan on heart function
“The effects of triclosan on cardiac function were really dramatic,” says Nipavan Chiamvimonvat, professor of cardiovascular medicine at UC Davis and a study co-author, according to the news release. “Although triclosan is not regulated as a drug, this compound acts like a potent cardiac depressant in our models.”
In addition, the mice had an 18-percent reduction in grip strength for up to 60 minutes after being given a single dose of triclosan. Grip strength is a widely used measure of mouse limb strength, employed to investigate the effects of drugs and neuromuscular disorders.
Finally, the investigators looked at the effects of triclosan exposure on fathead minnows, a small fish commonly used as a model organism for studying the potential impacts of aquatic pollutants. Those exposed to triclosan in the water for seven days had significantly reduced swimming activity compared to controls during both normal swimming and swim tests designed to imitate fish being threatened by a predator.
“We were surprised by the large degree to which muscle activity was impaired in very different organisms and in both cardiac and skeletal muscle,” said Bruce Hammock, a study co-author and professor in the UC Davis Department of Entomology. “You can imagine in animals that depend so totally on muscle activity that even a 10-percent reduction in ability can make a real difference in their survival.”
The UC Davis research team has previously linked triclosan to other potentially harmful health effects, including disruption of reproductive hormone activity and of cell signaling in the brain
Chiamvimonvat cautioned that translating results from animal models to humans is a large step and would require further study. However, the fact that the effects were so striking in several animal models under different experimental conditions provides strong evidence that triclosan could have effects on animal and human health at current levels of exposure.
“In patients with underlying heart failure, triclosan could have significant effects because it is so widely used,” Chiamvimonvat said. “However, without additional studies, it would be difficult for a physician to distinguish between natural disease progression and an environmental factor such as triclosan.”
Pessah questioned arguments that triclosan — introduced more than 40 years ago — is safe partly because it binds to blood proteins, making it not biologically available. Although triclosan may bind to proteins in the blood, that may not necessarily make the chemical inactive, he said, and actually may facilitate its transport to critical organs. In addition, some of the current experiments were carried out in the presence of blood proteins, and disrupted muscle activity still occurred.
Although triclosan was first developed to prevent bacterial infections in hospitals, its use has become widespread in antibacterial products used in the home. However, according to the U.S. Food and Drug Administration, other than its use in some toothpastes to prevent gingivitis, there is no evidence that triclosan provides other health benefits or that antibacterial soaps and body washes are more effective than regular soap and water. Experts also express concern about the possibility of resistant bacterial strains developing with the overuse of antibacterial products.
Because the chemical structure of triclosan resembles other toxic chemicals that persist in the environment, the FDA and the U.S. Environmental Protection Agency are conducting new risk assessments of the chemical. Based on their study outcomes, the researchers argue that the potential health risks call for greater restrictions.
Scientists show how triclosan potently impairs muscle functions
“We have shown that triclosan potently impairs muscle functions by interfering with signaling between two proteins that are of fundamental importance to life,” says Pessah in the news release. “Regulatory agencies should definitely be reconsidering whether it should be allowed in consumer products.”
Said Hammock in the news release: “Triclosan can be useful in some instances, however it has become a ubiquitous ‘value added’ marketing factor that actually could be more harmful than helpful. At the very least, our findings call for a dramatic reduction in its use.”
A copy of the study, titled “Triclosan impairs excitation-contraction coupling and Ca2+ dynamics in striated muscle,” can be requested by e-mailing PNASNews@nas.edu.
Other authors of the study were Gennady Cherednichenko, Rui Zhang, Erika Fritsch, Wei Feng and Genaro Barrientos of the UC Davis School of Veterinary Medicine; Roger Bannister and Kurt Beam of the University of Colorado Denver-Anschutz Medical Campus; Valeriy Timofeyev and Ning Li of the UC Davis Division of Cardiovascular Medicine; and Nils Schebb of the UC Davis Department of Entomology.