And that's grounds for concern, researchers say.
Agricultural entomologist Christian Nansen of the UC Davis Department of Entomology and Nematology and four colleagues analyzed 15 brands of roasted coffee beans, purchased at an area supermarket on two dates about six months apart, and using hyperspectral imaging technology, found “they were all over the board.”
“There was no consistency in the protein/sugar content and within the roasting classes of light, medium, medium dark, and dark or between sampling dates,” said Nansen, who specializes in insect ecology and remote sensing and uses imaging technology to quantify variability and identify trends and patterns in biological systems. “I thought this would be interesting to apply my hyperspectral imaging technology to a commercial system rather than a biological system.”
The research, “Using Hyperspectral Imaging to Characterize the Consistency of Coffee Brands and Their Respective Roasting Classes" is published in the current edition of the Journal of Food Engineering. Hyperspectral imaging involves collecting and processing information from across the electromagnetic spectrum.
Co-authors of the paper are postdoctoral research Keshav Singh of the Nansen lab; assistant professor Christopher Simmons and doctoral candidate Brittany Allison, both in the UC Davis Department of Food Science and Technology; and Ajmal Mian of the University of Western Australia's Computer Science and Software Engineering.
The study is not only relevant to the coffee industry and consumers but to a wide range of commercial food and beverage brands, Nansen said. Statistics show that Americans, the leading consumers of coffee in the world, consume 400 million cups of coffee per day. They spend an average of $21 per week on coffee.
Nansen, a coffee drinker, came by the topic naturally and also out of curiosity. “I got interested in this topic because I like coffee but also because I am certain that many food and beverage products vary markedly in quality. I thought this would be interesting to apply my hyperspectral imaging technology to a commercial system rather than a biological system.”
“The uniqueness and consistency of commercial food and beverage brands are critically important for their marketability,” the researchers wrote in the abstract. “Thus, it is important to develop quality control tools and measures, so that both companies and consumers can monitor whether a given food product or beverage meets certain quality expectations and/or is consistent when purchased at different times or at different locations.”
“We acquired hyperspectral imaging data (selected bands out of 220 narrow spectral bands from 408 nanometers to 1008 nanometers from ground samples of the roasted coffee beans, and reflectance-based classification of roasting classes was associated with fairly low accuracy.”
Their research provides evidence that the “combination of hyperspectral imaging and a general quality indicator (such as extractable protein content) can be used to monitor brand consistency and quality control,” the scientists wrote. “We demonstrated that a non-destructive method, potentially real-time and automated, and quantitative method can be used to monitor the consistence of a highly complex beverage product.”
The research was funded in part by Mian's ARC Fellowship.
It's in the current edition of The American Entomologist.
The UC Davis team, captained by Mohammad-Amir Aghaee of the Larry Godfrey lab, included members Danny Klittich of the Michael Parrella lab; Jenny Carlson, Anthony Cornel lab; Margaret "Rei" Scampavia, Neal Williams/Edwin Lewis lab; and Ralph Washington Jr., Steve Nadler lab.
The UC Davis debate team was assigned the “con” side of the topic, “Neonicotinoids Are Causing the Death of Bees Essential for Pollinating our Food Crops. The Use of Neonicotinoids Should End.” Auburn (Ala.) University drew the “pro” side. UC Davis defeated Auburn University and then went on win the overall student debate championship in the six-team, three-topic competition.
The neonicotinoid debate drew widespread attention. Below are the summaries distributed here in open access, Creative Commons:
Neonicotinoids are causing the death of bees essential for pollinating our food crops. The use of neonicotinoids should end.
Washington State University
Honey bees, bumble bees, and solitary bees are among the important biotic couriers transporting pollen from the male anther to the female stigma of flowers, playing a fundamental role in the fertilization and fruiting of angiosperms. The mutualism between bee pollinators and flowering plants is essential to approximately 35% of global agriculture (Velthuis and van Doorn 2006, Klein et al. 2007) and critical to many aspects of native ecosystems worldwide. However, this critical link is threatened by the decline of bee populations. The source of bee decline is multi-faceted; suspected causes of colony collapse disorder (CCD) in honey bees include, but are not limited to, biotic factors such as parasitic mites, pathogens, and resource availability/diversity, as well as abiotic factors including climatic change, land-use change, pollution, and pesticides (Decourtye et al. 2010, Neumann and Carreck 2010, Kluser et al. 2011, Girolami et al. 2012). The decline of native North American pollinators has the potential to disrupt the integrity of ecosystems and agricultural prosperity (Cane and Tepedino 2001). Native bee decline could be due to a number of reasons: the establishment of monocultures and disturbance of their native habitat; disruption in the pattern of bloom; the replacement of native flora with crop plants; or widespread insecticide use (Cane and Tepedino 2001). Among the classes of insecticides registered today, neonicotinoids are one of the most used insecticides worldwide, and are at the forefront of the investigation to determine the contributing factors to CCD (Girolami et al. 2012).
Neonicotinoid insecticides are effective against a broad range of chewing and sucking insect pest species (Zhou et al. 2013) and are registered for use in a wide variety of crops, including cereals, corn, cotton, oilseed rape, sunflowers, and sugar beets. This insecticide can be applied as a highly effective systemic seed coating, in the form of foliar sprays, or incorporated as a soil drench (Elbert et al. 2008, Yang et al. 2008, Blacquiére et al. 2012). All neonicotinoids are agonists of the insect nicotinic acetylcholine receptor (nAChR) (Matsuda et al. 2001, Elbert et al. 2008), causing excitation of the nervous system, paralysis, and eventually death of exposed, susceptible insects. While neonicotinoids are generally considered selective for insects and safe against mammals and birds, beneficial arthropods are still susceptible. Beneficial insects can come in contact with neonicotinoids if they feed on contaminated plant tissues or excretions, or are consequently exposed to the insecticide by ingesting contaminated prey (Prabhaker et al. 2011). When applied according to label instructions, neonicotinoids are not likely to come into direct contact with blooms, reducing contact with pollinators. However, neonicotinoids are highly potent and effective systemically; this class is highly soluble in water and can be moved by the plant translaminarly (Girolami et al. 2009).
Because of the value of pollination services provided by bees, and the widespread use of neonicotinoids, it is critical that the role of these pesticides in pollinator decline be determined. This will allow for informed decisions regarding future use of this class of pesticides.
Julian Golec, Matthew Burrows, C. Scott Clem, Adekunle Adesanya, Zi Ye, and Olufemi Ajayi
Advisor: David Held
Overwhelming evidence points to neonicotinoids as a critical factor in population declines of honey bees, bumble bees, and solitary bees (Sandrock et al. 2014). Neonicotinoids are the most widely used insecticide in agroecosystems due to their systemic properties (Hopwood et al. 2012), yet the impacts of neonicotinoids on bees extend beyond their use in agricultural settings. In urban settings, neonicotinoids can be applied at rates 120 times greater than those approved for agricultural settings (Hopwood et al. 2012). As a result, treated plants retain unmetabolized, active residues in virtually all plant parts, including pollen, nectar, and guttation fluids (Girolami et al. 2009). The effects of neonicotinoids vary based on the duration (acute or long-term exposure), route of exposure (oral or contact), and the bee species tested (Hopwood et al. 2012). In addition to outright mortality of individual bees, there are also sublethal effects implicated that affect bees at the colony level. For example, decreases in bumble bee queen production, pollen foraging efficiency, worker size, the rate of larval development, and learning abilities have all been implicated as sublethal effects of neonicotinoids (Decourtye et al. 2004, Gill and Raine 2014, Whitehorn et al. 2012). Additionally, these chemicals have been documented to affect immune responses in bees, making them more susceptible to pathogenic infections such as viruses and Nosema microspores (Alaux et al. 2010). Moreover, synergistic interactions between neonicotinoids and fungicides have been documented (Iwasa et al. 2004), which may indicate interactive effects with other chemical classes, increasing the negative impact on bees.
Current risk assessment protocols regarding the impacts of neonicotinoids on honey bees are insufficient, as they are focused on acute toxicity levels and do not incorporate various routes of exposure (Blacquiére et al. 2012). Shockingly, assessments for native bees are virtually nonexistent (Hopwood et al. 2012). Due to these factors, the U.S. Environmental Protection Agency (EPA) has recently called for a review of the current protocols in order to develop new risk assessment parameters (EPA 2012). Ahead of the U.S., the European Union (EU) has temporarily banned the use of neonicotinoids until further research can address sublethal and synergistic effects (van der Sluijs et al. 2013). The U.S. should follow the efforts of the EU and temporarily ban the use of neonicotinoids before irreversible damage occurs to an already stressed food industry and an increasingly less diverse ecosystem.
Historically, the 1996 Food Quality Protection Act (FQPA) restricted the use of toxic organophosphates, which lead to the creation of a new and presumably “safer” class of insecticides: the neonicotinoids (van Steenwyk and Zalom 2005). However, research has primarily focused on the European honey bee (Apis mellifera L.), and a few native bees (e.g. Osmia lignaria Say). It has since been found that the neonicotinoids are not a suitable alternative to older chemistries (Abbott et al. 2008). By using precedents set forth by the FQPA, the U.S. should temporarily cease the use of neonicotinoids until their effects at both the individual and colony levels can be thoroughly understood. We believe that a temporary ban on this insecticide class will lead to the discovery of new and safer insecticides, ultimately replacing the neonicotinoids.
Mohammad-Amir Aghaee, Jenny Carlson, Daniel Klittich, M. Rei Scampavia, and Ralph Washington, Jr. University of California, Davis
Advisor: Michael Parrella
However, the relationship between neonicotinoid use and pollinator decline remains disputed. Neonicotinoids were registered as reduced-risk pesticides because of their insect-specific action and low mammalian toxicity (van der Sluijs et al. 2013). They were selected to replace the organophosphates, carbamates, and pyrethroids, which have known non-target effects on humans and wildlife (Fairbrother et al. 2014).
Acute and chronic studies have shown that neonicotinoids are toxic to honey bees and bumble bees (Blacquiére et al. 2012). However, numerous studies implicating neonicotinoids as a cause of honey bee losses are insufficient in rigor and depth. Studies testing toxicity at field-realistic dosages between 1-10 ppb have shown inconsistent results (Cresswell et al. 2012). In addition, not all neonicotinoids have the same level of toxicity to bees. Acetamiprid and thiacloprid have an LC50 that is five orders of magnitude less toxic than clothianidin, thiamethoxam, and imidacloprid (Brown et al. 2014).
In addition, many other factors have been documented as contributing to pollinator decline (United States Department of Agriculture [USDA] 2013). Varroa destructor (Anderson and Trueman), a mite that feeds on the hemolymph of pupae and adult bees, vectors deformed wing virus and is a principal component of colony declines. Acaricides used to control Varroa are ubiquitous in wax comb of honey bee hives. These chemicals have been shown to compromise immune response in bees, impair honey bee behavior, and reduce the number of queens (Boncristiani et al. 2012). Pathogens such as Nosema ceranae (Fries) have impacted domesticated honey bee colonies, and N. bombi (Fantham and Porter) has wreaked havoc on native bumble bee populations (Mayack and Naug 2010, Evans and Schwarz 2011).
The lack of adequate nutrition further stresses colonies (Naug 2009). This results from a combination of habitat fragmentation and land-use changes that reduce the amount of wild forage available to honey bee colonies during periods of low food supply. Native pollinator populations are especially sensitive to habitat fragmentation and loss (Potts et al. 2010). This problem is compounded by the increasing demand for pollination services in agriculture (Aizen and Harder 2009).
Pollination demand created by almond production exemplifies the synergy of all these factors against honey bees. Every February, over two million colonies are moved to California to pollinate the almond bloom. Colonies are placed in staging areas at high concentrations and fed artificial diets to supplement a lack of natural forage (Fairbrother et al. 2014). These are optimum conditions for transmitting viruses and mites between colonies.
The best approach towards addressing pollinator declines would be to improve management practices to protect pollinators in crops (USDA 2013). This includes banning certain application strategies such as seed treatments. To this end, regulatory agencies need to have stricter registration guidelines that incorporate more comprehensive bee toxicity data, such as sublethal and synergistic effects on colonies, for all pesticides and methods of application (Hopwood et al. 2012). It is very important that growers are also educated on the proper use of these pesticides, which will prevent accidental losses of honey bees.
There is no definitive scientific evidence that neonicotinoids are the primary cause of pollinator declines. Given the current state of knowledge, banning neonicotinoids is a premature and disproportionate response to a complex issue. This issue requires holistic scientific inquiry and interpretation, and cooperation among stakeholders. Any changes must be based on science rather than opinion, current trends, or fear.
The distinction recognizes outstanding Senate faculty who have achieved the highest level of scholarship. "These are scholars whose work has been internationally recognized and whose teaching performance is excellent," according to the website.
Leal, former professor and chair of the UC Davis Department of Entomology, serves as a mentor in the campuswide Research Scholars Program in Insect Biology (RSPIB), launched in 2011 and administered by UC Davis Department of Entomology and Nematology faculty members professor Jay Rosenheim, associate professor Louie Yang and assistant professor Joanna Chiu.
RSPIB aims to provide academically strong and highly motivated undergraduates with a multi-year research experience that cultivates skills that will prepare them for a career in biological research. The annual deadline for undergraduates to apply is April 10.
Leal joins five other current or former faculty members of the UC Davis Department of Entomology and Nematology with the “distinguished professor” title: nematologists Howard Ferris and Harry Kaya and entomologists Bruce Hammock, Frank Zalom, Thomas Scott (now emeritus) and James R. Carey. Most are affiliated with RSPIB: Leal, insect physiology; Hammock, insect biochemistry; Zalom, integrated pest management, and Carey, insect demography.
Leal serves as co-chair the International Congress of Entomology (ICE) meeting, to take place Sept. 25-30, 2016 in Orlando, Fla.
Spotlighted are parasitologist and entomologist Shirley Luckhart, professor in the UC Davis School of Medicine's Department of Medical Microbiology and immunology and the Department of Entomology and Nematology; medical entomologist Gregory Lanzaro, professor, Department of Pathology, Microbiology and Immunology (PMI), UC Davis School of Veterinary Medicine, and an associate of the UC Davis Department of Entomology and Nematology; chemical ecologist Walter Leal, professor in the UC Davis Department of Molecular and Cellular Biology and former chair of the UC Davis Department of Entomology; virologist Lark Coffey of PMI; and UC Davis post-doctoral researcher Young-Moo Choo of the Leal's lab who discovered a receptor by dissecting mosquitoes' mouthparts and genetically testing them.
The KQED piece, drawing widespread interest, is the work of Gabriela Quirós, coordinator producer of Deep Look, KQED Science.
Luckhart said that the mosquitoes detect body heat and substances called volatile fatty acids. “The volatile fatty acids given off by our skin are quite different," Luckhart told Quirós. "They reflect differences between men and women, even what we've eaten. Those cues are different from person to person. There's probably not one or two. It's the blend that's more or less attractive.”
“Mosquitoes don't find the blood vessel randomly," Leal said, pointing out that the receptors respond to chemicals in the blood.
The receptor that the Leal lab discovered is called 4EP, and may lead to drug companies developing new mosquito repellents. “First they'd need to find a repellent against the receptors," Choo told Quirós. "Then they'd treat people's skin with it. When the mosquito tried to penetrate the skin, it would taste or smell something repulsive and fly away.”
Lanzaro said that the latest malaria statistics--more than 300 million people contracted malaria in 2015, and some 635,000 died--are "probably an underestimate."
Undergraduate student Jessica West, Ph.D. candidate Rosanna Kwok, and research specialist Katherine “Katie” Murphy all excel in STEM, an acronym that stands for the academic disciplines of “science, technology, engineering and mathematics.”
“Undergraduates who learn cutting-edge research skills in laboratories like Dr. Chiu's set themselves apart from students who only pursue coursework for their degree,” said Steve Nadler, professor and chair of the UC Davis Department of Entomology and Nematology. “Undergraduate research opportunities are what turn science students into young scientists.”
Early in their undergraduate studies, West and Murphy were accepted into the UC Davis Research Scholars Program in Insect Biology, a vigorous, multi-discipline, research and mentoring program administered by UC Davis Department of Entomology and Nematology faculty members Jay Rosenheim, Louie Yang and Chiu.
"Including this year, over the first six years that the program has operated, we have admitted 58 students, 36 of which (62%) are women," said Research Scholars Program co-administrator and professor Jay Rosenheim.
"It is asking a lot of freshmen and sophomores to jump into an intensive research experience when they are already challenged by their academic course load," Rosenheim said. "But we've been very gratified with the accomplishments of the students and their demonstrated abilities to develop the skills needed to conduct independent research. Strong effort by the students and close mentorship by campus faculty seem to be key ingredients in student success.”
West, who will receive her bachelor's degree in bochemistry and molecular biology June 12, is the recipient of the 2016 College of Biological Sciences Medal—only one is awarded each year. She also won an “Outstanding Citation for Research Performance.” Although not yet in graduate school, West has already published two peer-reviewed articles. In November 2015, she received the President's runner-up prize at the Entomological Society of America (ESA) meeting in Minneapolis for her talk on the seasonal biology of the spotted wing drosophila, Drosophila suzukii. This fall she will enroll in the Ph.D. program in biochemistry at Cornell University, Ithaca, N.Y. “Over her undergraduate graduate career, Jessica has compiled an impressive list of awards and prizes,” said Chiu, an assistant professor in the UC Davis Department of Entomology and Nematology.
Kwok, scheduled to graduate from UC Davis in the fall of 2016 with a Ph.D. degree in entomology, has already published six peer-reviewed papers, including one in PLOS Genetics, and has three more in preparation. As part of her requirement for her 2014-16 NIH fellowship, she will leave the Chiu lab in June 2016 to start an internship at OncoMed Pharmaceuticals, Inc. in Redwood City, CA. The internship is her last requirement before graduation from the Entomology Graduate Group.
Like West, Kwok received a President's runner-up prize (2013 ESA meeting) for her presentation on the chronotoxicity of spotted wing drosophila, working with Chiu and Professor Frank Zalom, integrated pest management specialist in the department. “I believe Rosanna will have a very successful career in the biotech industry,” Chiu said.
Murphy, who was accepted into the inaugural class for the Research Scholars Program in Insect Biology, began working in the Chiu lab her sophomore year. When she graduated from UC Davis in 2014 with a bachelor of science degree in neurobiology, physiology, and behavior, she received an “Outstanding Citation for Research Performance.” After graduation, she opted to stay in the Chiu lab to gain more research experience. “Over her career in my lab--from undergraduate research to two years of technician-- Katie has already published four peer-reviewed papers, has one currently in review, and two in preparation,” Chiu said. She is also an author on a provisional patent application for a biopesticide that the Chiu lab developed to target insect pests.
The three young women followed a similar path to get where they are today and strongly encourage others to pursue STEM careers.
Jessica West, who grew up in the Redding area of Northern California, spent her childhood in the small town of Shasta Lake before enrolling at UC Davis.
“I first became interested in science in high school, particularly when I took Advance Placement (AP) Biology,” West recalled. “ I was very curious and always asked a lot of questions in school. What excites me the most is that now I can ask questions that don't yet have answers, and through my research I can work to actually answer them.”
West, who will start her PhD program in biochemistry, molecular and cell biology at Cornell in the fall, says her career goal “ is to teach and conduct research at the university level.”
“I think it's important to start getting girls involved in science at a young age,” West said. “Often young girls are not encouraged to pursue their interests in STEM subjects, but I think that the culture is changing. There are programs like Girls Who Code that seek to get more girls involved in STEM fields that are traditionally male-dominated. If young girls can see that other women like them can succeed in STEM fields, they are more likely to see their goals as attainable.”
Rosanna Kwok grew up in Las Vegas, Nev. –“Yes, people actually live there,” she quipped. “I have always been interested in having a career in science,” she recalled, “and it just took a bit of exploration before I found myself studying the circadian clock under the mentorship of Joanna. The most exciting and motivating thing about being a scientist is knowing that I have the resources to answer the ‘how' and ‘why' questions regarding biological phenomenon.
Her career plan is “to contribute my background and skills to the field of precision therapeutics. It is hard to predict where I will be in a few years, but my goal is to be in an environment where I am constantly challenged and growing as a scientist.”
How to get more young women and girls interested in science? “Thankfully, I do believe that there is a much greater representation of women in sciences than there has in the past,” Kwok said. “With that said, I really believe in the importance of establishing mentoring relationships when it comes to retaining the amount of women in science. I have definitely benefitted from having strong female mentors throughout my scientific career. Many girls are discouraged starting from pursuing their curiosities, or from pursuing certain career paths, and sometimes it takes a more established person in that field to tell them to just go for it, and not apologize for wanting something different than what's expected of them.”
“I believe that in order to get more people in general interested in science, there needs to be more communication between scientists and people who are not in STEM fields,” Kwok said. “Not only will this show that large scientific achievements can be made by real people, it will also help prevent the misconceptions and distrust in science that we sometimes see."
Katherine “Katie” Murphy
Katie Murphy spent her childhood in a small rural town in Lake County, Northern California. “ I grew up on a pear farm, which exposed me to the staggering amount of fruit that goes to waste if the appearance of the fruit is not perfect enough for the grocery store,” she related. “I believe we have a duty as a society to be less wasteful, and therefore I feel inspired to find ways to turn waste into useful materials."
“I discovered my interest in science as a career through a student research position in Dr. Joanna Chiu's lab at UC Davis,” Murphy said. “I believe the greatest challenges that face the world today, such as world hunger, global warming, and the energy crisis, can only be met through technological advancement. I am excited for the opportunity to develop new technologies that use cutting edge science to make the world a better place.”
As an undergraduate research assistant, she was awarded a UC President's Undergraduate Research Fellowship for the summer/fall of 2012 for her project, “Transgenic Yeast as an Organic Pesticide.” She explored the use of RNAi technology in combating the invasive pest, the spotted-wing drosphila, Drosophila suzukii.
Murphy's career plans? “I am pursuing a career in metabolic engineering,” she said. “The technology I hope to develop uses microbes to produce fuels and chemicals from ‘leftovers' such as agricultural waste and non-edible plant materials. This technology will reduce dependency on fossil fuels and provide sustainable energy alternatives."
When asked how society can engage more young women and girls in science, she commented “I think children and adolescents of both genders can benefit from greater exposure to STEM fields. In the media, scientists are often represented as evil, mad, or even downright uncool on TV shows such as The Big Bang Theory. What about a TV show where scientists and engineers are portrayed as heroes?”
The Research Scholars Program in Insect Biology, established in 2011, aims to provide academically strong and highly motivated undergraduates with a multi-year research experience that cultivates skills that will prepare them for a career in biological research. This could result in career goals that will take them to medical school, veterinary school or graduate program sin any biological sub-discipline, the administrators said. Because insects can be used as model systems to explore virtually any area of biology (population biology; behavior and ecology; biodiversity and evolutionary ecology; agroecology; genetics and molecular biology; biochemistry and physiology; cell biology), faculty in the program can provide research opportunities across the full sweep of biology. More information on the program is at http://ucanr.edu/sites/insectscholars/