Originally posted on the IEAM blog on 17 August
This post is the last in our series of updates from the SETAC Brussels meeting. We hope you enjoyed our coverage of toxicology research from the meeting!
What are microplastics and why should we care about them?
Microplastics are pieces of plastic or polymer debris that are very small in size, ranging from a shard as narrow as the width of a hair to a piece as large as a marble. Microplastics include pieces of plastic that are broken down from larger items, such as single-use water bottles, or ‘microbeads’ that are added to certain soaps and exfoliators.
Even though microplastics are small, there are concerns they can cause serious damage. Animals that confuse microplastics for food can end up with internal lacerations, inflammation, and nutrient deficiency caused by eating too much inedible material. Microplastics are also widely spread across the globe—scientists calculated that up to 90% of marine birds have ingested microplastics.
Plastic waste can be found everywhere. Coupled with predictions that plastic production could increase to 33 billion tons each year by 2050, it appears that microplastics are not going away anytime soon. Major news outlets regularly highlight the pervasive nature of this waste, including the story of the recent discovery of over 37 million pieces of plastic garbage on a South Pacific island.
Environmental toxicology researchers at the SETAC Brussels meeting (May 2017) presented a range of studies exploring the impacts of microplastics and addressing the challenges that we face in combating this pervasive, persistent, and tiny pollutant. In this post we highlight some of the findings presented during the sessions “Challenges and best practices in monitoring of micro- and nanoplastic abundance and environmental distribution” and “Microplastics, nanoplastics and co-contaminants: Fate, effects, and risk assessment for biota, the environment and human health.”
Microplastic monitoring: Where does it come from and where does it go?
One of the challenges for researchers is that microplastics comprise a large and diverse group of materials, including various sizes, shapes, materials, and sources. Some microplastics are formed by the breakdown of larger materials, while others are added into household products (e.g., microbeads), so it’s difficult to trace the fate of these materials.
Beate Baensch-Baltruschat from the German Federal Institute of Hydrology conducted a survey of plastic monitoring in European freshwater ecosystems. She found that rivers and streams are important for following the movement of plastics since these waterways are a major route for microplastics on their journey to the ocean. The survey looked at active sampling efforts by ten countries across Western and Central Europe. Monitoring data collected by these surveys revealed that there is a wide range of microplastic sizes, with larger particles (0.1 mm to 10 mm) more prevalent in surface waters and smaller particles found primarily in sediments.
Jes Vollertsen (Aalborg University) noted the problem of how the transport of microplastics during stormwater runoff events was not well-understood. To explore the issue, his research group sampled water and sediment from stormwater retention ponds in Denmark to examine microplastic levels. Their survey found that stormwater can hold up to 10 micrograms of microplastics per liter, and that nearly half of this plastic waste builds up in the sediment while the other half slowly discharges out of the pond water over time. Both Vollertsen and Baensch-Baltruschat’s work highlight the importance of monitoring and tracking microplastic movement in different types of environments.
Fabienne Lagarde from the Institute of Molecules and Materials studied how mussels were impacted by microplastic contamination along the Atlantic coast of France. Lagarde and her team identified 73 microplastics across all of the mussels they sampled over two sites, seasons, and habitats (wild caught versus cultivated environments). Eighty-five percent of the particles were polyethylene and polypropylene. Polyethylene is primarily found in single-use plastics such as bags and bottles, while polypropylene is made for more durable materials like plastic pipes and furniture. While microplastic levels did not differ significantly between seasons, sampling sites, or habitats, Lagarde’s results highlight the pervasive nature of microplastic contamination. Over 140,000 tons of mussels are produced in France every year, so studies like this are crucial for understanding potential risk to seafood consumers.
Some microplastics are in the form of fibers, shed from synthetic clothing during laundering. When these plastic microfibers enter the waste stream, pieces that are too small to be filtered out (microfibers) are discharged into the environment. Imogen Napper (Plymouth University) measured microfibers released from wash cycles with synthetic materials and found that a typical 6-kg wash of polyester-cotton blend clothing releases 137,000 fibers into wastewater. Even more microfibers are released from polyester materials (nearly 500,000) and acrylic clothing (728,000 fibers). Napper proposed a straightforward solution of including filters on washing machines to collect microfibers in order to reduce the large number of them that are discharged into the environment.
Microplastic effects: Are microplastics harmful to marine wildlife?
Inger Lise Nerland from NIVA discussed her work examining the impacts of polyethylene microbead exposure on Mediterranean mussels. Nerland exposed mussels to microbeads isolated from toothpaste for 3 weeks. The study was designed to reflect what happens in an actual environmental exposure by weathering the microbeads (allowing the material to break down naturally in seawater) before the exposure started. Nerland and her group found that not only did mussels ingest the microbeads, but that mussels with plastic particles had a higher number of blood cells in their gills, thinner gill tissues, and clumps of blood cells in their digestive system. This study provides more support for the hypothesis that microbead exposure can cause damage to the wildlife they come in contact with.
Theresee Karlsson (University of Gothenburg) looked at how single-use polyethylene bags break down in seawater. These single-use bags are very lightweight, yet somehow scientists find polyethylene deep in ocean sediments. Karlsson cut single-use bags into pieces of various sizes and placed the bags in stainless steel cages. Karlsson’s study showed that the amount of time that plastic pieces were left to degrade influenced the growth of microorganisms, or biofilms, on the plastic. The presence of biofilms changed the density of the plastic waste due to a build-up of calcium and silica. The example of how polyethylene bags change in density when they are bound by biofilms demonstrates how plastic waste cannot be classified in any broad, all-encompassing manner—even waste that starts off as the same material can have a completely different fate based on how it interacts with the environment.
Adam Porter from the University of Exeter highlighted his work demonstrating the importance of marine snow—organic matter, such as decaying animal and plant material, that falls from the surface levels of the ocean into the deep sea. This ‘snow’ is responsible for moving nutrients from the ocean’s surface down to the organisms living in the depths of the ocean. Porter’s work provides evidence on how marine snow affects the movement of microplastics. Porter measured microplastic sinking rates in artificial water columns both with and without artificial marine snow and also measured the difference in microplastic uptake in mussels. This study found that marine snow can bring lightweight microplastics to lower parts of the water column, and that mussels consumed more microplastics if marine snow was present. Porter’s work highlights the importance of considering deep sea organisms studying effects of microplastics in the marine environment.
Ricardo Beiras (University of Vigo) described how microplastics can bind other chemicals, becoming inadvertent vehicles for chemical exposure. Polymers and plastics contain many additives that can absorb other chemicals, so animals who consume microplastics might accidentally also be eating toxic chemicals. Beiras exposed sea urchin larvae to microplastics that were incubated with a toxic chemical (nonylphenol). While the plastic particles did absorb nonylphenol and the larvae did eat the plastic particles, Beiras did not find any evidence that nonylphenol was transferred to the larvae through the microplastics.
There is still a lot of work to be done to gain a better understanding the environmental fate and impacts of microplastics. Several sessions held at SETAC Brussels brought together researchers from numerous fields to share their work. This post represents just a small part of the global effort to understand and mediate the impacts of plastic pollution for both environmental and human health.
For those who want to help in the effort to reduce microplastics, you can start by using your own shopping bag instead of a single-use bag at the grocery store and look for alternatives to cleaning products containing microbeads.
Originally posted on the IEAM blog on 15 August as part of our SETAC Brussels session summaries series.
Circular economy, LCA, and the environment
As we consumers become more aware of how the products we buy and use impact the health of the environment, companies are also looking for ways to make more sustainable products using materials with a more positive environmental impact. Life cycle analysis (LCA) is a way for environmental scientists to clarify the environmental impacts of a material or product. A circular economy is a system of production and consumption that is powered by renewable energy. A clean circular economy also focuses on eliminating toxic chemicals and closing material loops through better design, maintenance, repair, reuse, refurbishing, and recycling.
An LCA includes everything that goes into the creation of a consumer product: gathering raw materials (like wood, coal, or metal), manufacturing the product (the type of factory used, what energy goes into production), how the product is used (single use versus multiple uses), and what happens to the product when it is no longer needed (what components are disposed or recycled). An LCA is completed using three steps: 1) inventory analysis (identify all inputs and outputs, where materials come from, where they end up, and the energy inputs and outputs related to the creation of the product), 2) impact analysis (a value known as an ‘impact score’ indicates the impact of each step in the manufacturing process), and 3) improvement analysis (finding places in the process that can be improved to reduce the impact score, like using less energy).
LCA helps companies understand what they can do to make products more sustainable, reduce negative impacts on the environment, and produce less toxic by-products. Product manufacturing is extremely complex however: raw materials are sourced from around the world, all of which are obtained in different ways depending on the country of origin and the type of material. Companies are constantly looking for better ways to determine the sustainability of new products.
At the SETAC Brussels meeting held in May 2017, researchers presented the latest advancements within LCA towards solving real-world problems in sustainability. Here we highlight the findings from the special session “Think-Outside-The-Box-Session: Clean circular economy: recycling while eliminating legacy toxics” organized by Dr. Niels Jonkers (Ecochain) and Dr. Heather Leslie (VU Amsterdam). We also highlight a selection of platform presentations from the “Advancements in life cycle impact assessment and footprint method development” session chaired by Serenella Sala (Joint Research Centre).
Creating a clean circular economy
Sicco Brandsma from VU Amsterdam highlighted the science behind recent health concerns on the use of recycled tires and rubber for recreational fields. Nearly 90% of all artificial soccer fields in countries like the Netherlands are made of recycled rubber granules, and a single playing field can use up to 20,000 recycled tires. EU regulations currently limit the amount toxic chemicals, such as polycyclicaromatic hydrocarbons (PAHs) that can be found in recycled rubber on playing fields to 100 mg of chemical per kg of rubber material. But Brandsma pointed out that regulations for other rubber products, such as children’s toys and rubber playground flooring require much lower maximum concentrations of PAHs, closer to the 1 mg/kg range. Brandsma highlighted the need for further research in this area that can address the concerns consumers have about the presence of rubber in places that people come into contact with on a regular basis.
Jane Muncke (Food Packaging Forum Foundation) gave a perspective from the food packaging industry on the future of the circular economy. Food consumption makes up close to one third of all human-induced environmental impacts across the world. Part of this impact is due to waste from food packaging, and the industry is attempting to address these challenges while making sure that chemicals used in food packaging are not toxic. There are currently 8,000 chemicals regulated by the EU in food packaging materials, but Muncke said that monitoring all 8,000 chemicals and understanding how the manufacturing process impacts chemical composition remains a challenge.
Muncke highlighted the importance of food package recycling in order to achieve a complete circular economy but stressed that material recycling should not be done in a way that increases human contact with potentially hazardous chemicals. Proposed solutions include ensuring that food containers are recycled but then reused in a manner consistent with their original purpose, such as reusing cold food containers to hold cold food again and not hot food (where the heat could cause some of the chemicals to leech out).
Giorgia Faraca (Technical University of Denmark) talked about on finding safe ways to recycle and reuse wood products. The challenge in this area is the presence of impurities in wood, such as metals, plastics, and chemical additives including paints and oils. There are EU regulations in place to prevent contact with hazardous materials in recycled wood, but Faraca stated that these regulations also make it a challenge to ensure that high-quality wood materials can be reused instead of simply thrown away. Faraca and her team found that some chemical impurities could be removed completely before recycling. She commented that while some impurities may still occur in recycled wood materials, low enough levels ensure that the material could still be used safely by consumers.
Arthur Haarman from EMPA Technology and Society Lab discussed work on electronic waste. Electronic waste (e-waste) is a fast-growing waste stream in the developing world that includes materials such as used computers and television sets. This waste stream is attractive to recyclers because it contains valuable minerals like copper. However, this waste stream also includes highly toxic materials such as flame retardants and heavy metals. Haarman said that of the 42 million tons of e-waste generated in 2014, only 15% of materials entered a formal and proper recycling and waste treatment process. Haarman then discussed e-waste in India, where informal regulations and cultural perspectives can lead to unsafe handling of hazardous materials. There are ways for recyclers in India to handle plastic contaminated with toxic chemicals, but Haarman reported that the initiatives for recyclers to undergo additional separation steps are not working. Haarman and his group studied the trends of e-waste recycling in India and developed a strategy, coupled with easy-to-use testing methods, that provides greater incentives for removing toxic chemicals from e-waste.
New advances in LCA
Caroline Catalan (I Care & Consult) presented new LCA methods for measuring a product’s impacts on biodiversity. Once finalized, this new LCA method will be able to measure how different versions of a product relate to measures of ecological richness. This method will provide a way to calculate the total ecological footprint of a product, providing a new way for companies to use LCA to ensure that their products are sustainable. Catalan also hopes that the results of this project will provide a connection between ecologists and LCA researchers that is both scientifically and economically sound.
Mathilde Vlieg (Evah Institute) discussed a case study aimed at calculating carbon credits from wood products. Vlieg emphasized the importance of accounting for carbon storage during LCA because of the ability for timber products to uptake carbon before harvest. This carbon remains stored if the materials are recycled, and carbon is released back into the environment if they are burned or allowed to decompose. Vlieg presented data from suppliers and manufacturers, with endpoints including forest age and fire history to calculate carbon sequestration. Long-term models developed for this LCA showed that up to 90% recovery of wood materials is possible even after 60 years of use. These results provide further support to the study of carbon sequestration potential of wood materials and their application in LCA.
Karoline Wowra (TU Darmstadt) discussed the importance of nitrogen in LCA. An over-abundance of nitrogen from agricultural or fossil fuel production can lead to eutrophication, algal blooms, and oxygen depletion in freshwater ecosystems. Many LCA models already account for nitrogen levels but there are many regional differences in nitrogen levels and cycles. Wowra’s group compared different LCA methods to see if nitrogen levels were being incorporated accurately. She found that the specific nitrogen compounds studied and the geography of the region influenced how applicable the existing LCA methods were for a particular area under consideration. Wowra suggested that researchers select LCA methods depending on the goal or scope of the study, for example, an LCA focused on agricultural impacts should include more accurate measurements of specific nitrogen compounds relative to agricultural soil.
Bernard De Caevel at RDC Environment examined using a resource’s market price as a basis for its value within LCA. This project focused on the use of a non-renewable resource’s monetary value as a proxy for that resource’s environmental value. De Caevel and his team found that a material’s market price can be a valid substitute for determining value, but that social and market forces on a resource’s price still needs to be taken into account. His group will continue to develop other ways to determine the value of minerals and fossil reserves for completing LCAs on products which use those non-renewable resources.
What’s next for life cycle analysis, circular economy, and SETAC?
LCA is just one way that science is helping companies make greener products for consumers looking for safe and sustainable products. The SETAC Brussels meeting provided a forum for these researchers to discuss the challenges and considerations needed to apply these methods to address real-world challenges. SETAC will continue to play a role in the future of LCA as a place for researchers in the field to work together towards making the vision of a clean circular economy a reality.
Originally posted on the IEAM blog on 25 July 2017
Welcome to the 2nd post in our series of updates from the SETAC Europe Annual Meeting held in Brussels, Belgium from 7-11 May 2017. After this post we will have two more updates that will be online in the next couple weeks. Enjoy!
Are pesticides hurting pollinators?
The widespread loss of honeybee populations in Europe and the reduced numbers of wild bees in other countries sparked concern among scientists, policymakers, and farmers all across the world. Recent research conducted on historical field data found a potential connection between the use of certain insecticides and changes in wild bee populations. This was especially true for species that are known to visit flowering crops like oil seed rape.
While scientists have been looking in detail at how pesticides might be harmful to bees, there are still many questions on how to find the balance between protecting crops while ensuring the protection of bees and other pollinators. Managing both pesticide usage while mediating risks on wildlife populations continues to challenge scientists and policymakers.
Risk assessment is the primary tool that scientists use to address this challenge. A risk assessment is an evidence-based process that determines 1) how much of a toxic chemical can be found in a specific environment (the soil, water, or air) and how much an animal or person can come in contact with that chemical (called ‘exposure’), 2) how toxic the chemical is to an animal or person (hazard), and 3) the quantitative relationship between the two (risk). The three answers are used to calculate the risk a chemical poses in the environment.
In conducting bee and pollinator risk assessments, scientists are focused on logistical problems such as experimental set up, how much of a chemical a given pollinator will come in contact with, and determining the total toxicity of all of the pesticides currently in use. At the session “New developments in ecotoxicology for the risk assessment of single and multiple stressors in insect pollinators: From the laboratory to the real world” held at the SETAC Brussels meeting, scientists highlighted new findings that can help policy makers choose the best course of action to ensure that pollinators are protected when pesticides are used.
New findings on the impacts of pesticides to pollinators
Are all pollinators affected by pesticides in the same way?
To test whether different bee species respond to pesticides in the same way, David Spurgeon from the Center for Ecology and Hydrology exposed three bee species to several commercial pesticides and compared their responses. He exposed the European honeybee (Apis mellifera), the buff-tailed honeybee (Bombus terrestris), and the red mason bee (Osmia bicornis) to pesticides through their food and compared survival rates. Spurgeon and his group found that pesticide toxicity increased over time in all three species. This has implications for how scientists conduct regulatory toxicity tests on bees in the lab, and Spurgeon commented that scientists cannot rely on a single time point when trying to determine the overall risk from chemical exposure. This is especially relevant, he said, if the bees come in contact with the pesticide on a frequent and long-term basis.
Philipp Uhl from the University of Koblenz-Landau determined the toxicities of several pesticides and compared results between the European honeybee and the red mason bee. Because the European honeybee is the main test species for pesticide risk assessments in Europe, scientists are concerned that using only one pollinator species will make it difficult to accurately determine the risk to other species that may be more or less sensitive. Uhl found that the European honeybee was either more sensitive or had a similar sensitivity profile than the red mason to six of the tested pesticides. This means that using the European honeybee data to complete the risk assessments for these pesticides would be protective for other pollinator species. But for one set of pesticides, the European honeybee was less sensitive, and for certain pesticides there was a 100-times difference between the two species. Any risk assessments conducted using data generated from the honeybee would not provide results that would be protective to other species for these pesticides. Uhl concluded that these species-specific differences in chemical sensitivity should motivate scientists and policymakers to find better ways to test the most relevant species. Uhl commented that this data also indicates how chemicals should be used and what species of bees may be the first ones to be affected.
How do we design experiments to more accurately determine the effects of pesticides?
Natalie Ruddle from Syngenta discussed the importance of experimental design for evaluating toxicity in species other than the European honeybee. Ruddle presented a field study that was designed to determine the impacts of a neonicotinoid (thiamethoxam) on the red mason bee. Since this pollinator is a solitary bee and does not have a central hive nor a queen, Ruddle and her collaborators worked to develop a field method that can measure the reproductive capacity of individual females. Their field setup relied on the use of long half-dome greenhouses where plants and bees were housed together (known as a “tunnel design”). While no negative effects were seen in the red mason bee when they were housed with pesticide-treated oilseed rape plants, Ruddle highlighted the continued challenges of designing these types of field experiments for solitary bee species, noting the need for consensus on how to set up such experiments.
Stefan Kimmel from Innovative Environmental Services, Ltd. discussed the dynamics of how bees are exposed to pesticides in an open field, also using the solitary red mason bee and pesticide-treated oilseed rape plants. Kimmel and colleagues sampled pollinators before and after pesticide application and looked at the amount of pesticides in the flower buds, pollen, nectar, the bee foragers themselves and the hive entrance. Kimmel found that there was a gradient in pesticide concentration, with higher levels in crops and lower but detectable levels found in the nesting sites.
At the end of the session, presenters and audience members discussed the current and future needs for pesticides and pollinators based on EU regulations. While tests conducted in open fields are not currently accepted by regulators, due to concerns about competing crops, Kimmel commented that there are advantages of open-field techniques because the setting more accurately represents how pollinators can become exposed to pesticides and avoids the potential for any harm caused by tunnel confinement.
What’s next for pollinators?
We still have a lot to learn about how bees and pollinators are impacted by pesticide use. But thanks to a better scientific understanding of the risks that pesticides can have on bees in agricultural settings, scientists and policymakers are working together, now more than ever before, on empirical and creative ways to address this global problem.
The latest science presented at the SETAC Brussels meeting highlights how researchers, government institutions, regulators, and agrochemical companies are working together to find the best ways to protect pollinators. SETAC will also continue to be a place for scientists to work together with the Pollinators interest group now being developed within SETAC.
Originally posted on the SETAC IEAM Blog on 17 July 2017
We are finally kicking off the SETAC Brussels summary series! This post is the first of four highlights of research presented at the SETAC Europe Annual Meeting in Brussels, Belgium (7-11 May 2017). Each post features the latest research findings from SETAC scientists on emerging topics of interest. Enjoy!
Why does oceans health matter?
Oceans provide more for us than just the backdrop of our annual summer holidays—they provide food and medicine, help connect people and provide a means to deliver materials across the world, are a source of economic growth for coastal communities, and help moderate climate change. But our strong connection to the marine environment also comes with some drawbacks. Seafood contamination, marine pollution, biological hazards such as red tides and antimicrobial resistance (AMR), and rising sea levels are just a few of the examples of how our own health is closely linked to that of our environment.
A new and rapidly expanding field of research called Oceans and Human Health (OHH) examines the connections between our health and the health of marine environments. This work includes looking at both the benefits and the risks to people and how our actions can influence the health of marine ecosystems. The theme of OHH was prevalent at this year’s SETAC Brussels meeting, where a common theme of keynote and platform presentations was the interconnections between environmental science and human health.
“This area of research is very strategically important for the world, and very important for SETAC as an organization, to move into.” said Colin Janssen, one of the co-chairs of the OHH session. “SETAC researchers are now beginning to focus more on the marine environment, as we are recognizing more and more that human health is not isolated from the environment’s health.” A discussion around the theme was kicked off at the Opening Keynote Presentation by Lora Fleming (University of Exeter) and was followed by a series of platform and poster presentations.
The science that connects oceans and human health
Lora Fleming presented her collaborative work on red tide events in the state of Florida, in the US. Red tide is caused by microscopic algae (Karenia brevis) that release neurotoxins as aerosols, which are then transmitted by air and wind. Large outbreaks in Southwestern Florida were responsible for the deaths of many endangered Florida manatee and dolphin populations.
One significant result from this work was the finding that dolphins had eaten fish with trace amounts of red tide neurotoxin. Since dolphins do not eat dead fish, and it was previously thought that fish consumption did not confer a risk to neurotoxin exposure, these findings provided new evidence of the risks of consuming fish during red tide events. Fleming’s research team provided the evidence needed to change existing policies for red tide event management in order to better protect both marine and human health.
The human health impacts of red tide events could also be seen beyond the beach where direct exposure occurs. Fleming and her team found that red tide outbreaks were linked to increases in emergency room visits and exacerbated breathing problems for people with respiratory conditions such as asthma. Fleming’s work highlights the pervasive nature of red tide events, providing a better understanding of how people are affected by the health of the marine environment.
Maarten de Rijcke from Ghent University later presented results of a study focused on red tide pollution in the North Sea. Rijcke and his team placed caged mussels at a coastal sluice dock and looked for algal bloom neurotoxins in the mussels. Researchers found a complex mixture of toxins present in the mussels after only 15 days, and several of the neurotoxins they found had unknown toxicities. Rijcke highlighted the importance for looking at algal bloom toxins levels in economically important species, as well as looking at toxins more broadly, instead of only focusing on neurotoxins of known toxicities. He stated that chemicals which are not regularly monitored—or for which no toxicity data exist—might still have a negative impact on human health, and that these should be assessed when possible.
Antimicrobial resistance (AMR) in surfers
Anne Leonard, University of Exeter, presented research on how antibiotic resistance spreads through coastal environments. Coastal areas are strongly impacted by human activities, including run-off from agricultural fields and wastewater treatment plants, and are also a place that people have the most physical contact with the ocean.
Leonard collected coastal water samples and counted the numbers of Escherichia coli that could produce a protein that is able to provide resistance to several antibiotics. Leonard then conducted a survey of surfers compared to non-surfers to see if there was a connection between time spent in the ocean and the presence of drug-resistant E. coli. Volunteers provided rectal swabs and filled in questionnaires as part of the Beach Bum survey.
Data from the Beach Bum study shows that surfers were four times more likely to be colonized by drug-resistant E. coli when compared to people who did not surf. While there appeared to be no direct risk from the E. coli on this healthy population of surfers, Leonard commented that their presence in a healthy population means they can easily spread to more difficult-to-treat and sensitive patients. This research also shows that coastal recreational and occupational exposure to microbes might be a significant route of AMR transmission.
The benefits of interacting with the oceans
leming shifted the tone of the platform presentations to focus on the benefits gained through positive interactions with marine environments. She presented results from scientific surveys, interviews, and controlled experiments in the UK. Benefits include better health reported in people who live close to the ocean or other bodies of water, with the strongest effects seen in poorer communities. Her group also found a reported reduction in stress and an increase in physical activity after people visited coastal areas. Researchers also found that people who visited marine areas reported increased interactions among family members and had increased vitamin D levels. Fleming and her group are now working to understand and consolidate the benefits of “blue gyms” in the UK, findings which consistently demonstrate positive benefits from interactions with healthy marine environments.
What’s next for the field of oceans and human health?
A number of research projects across Europe and the United States will continue to conduct research on the connections between oceans and human health. These research projects are also looking to foster connections with other fields such as economics, psychology, and science communication. Learn more about these initiatives in the EU by visiting the Horizon 2020 Blue Health web page and the SeaChange ocean literacy project.
“If we can show that oceans really are valuable, in an economic sense as well as a public health sense, and that healthy ecosystems are good for our own health and well-being, we can promote more pro-environmental behavior in people.” said Fleming. “I hope that researchers in toxicology and public health will continue to take this topic forward as a truly transdisciplinary field. That we can value and treat our world better and own what we do to the environment in a positive way.”
A new study from Canada shows that preservatives commonly used in cosmetics, lotions, and shampoos can be found in the urine and breast milk of pregnant women.
The article, published in the April 4th issue of Environmental Science and Technology, looked at the relationship between how often pregnant women used personal care products and the levels of preservatives, specifically parabens, present in their urine and breast milk. The women in the study noted the cosmetics they used on a daily basis and researchers calculated if parabens levels were related to the number of personal care products used.
Scientists from Health Canada, Brown University, Harvard University, and the Ottawa Hospital Research Institute analyzed urine samples from 80 women from 2009-2010. All samples were collected during the second and third trimesters and breast milk samples were collected from 2-3 months post-partum. Women were asked to indicate the number and type of personal care products they used each day in a diary. Products were separated into categories such as deodorants, make-up, shampoos, conditioners, body lotions, hand soaps, and lip products. Four different types of parabens were measured by chemical analysis: butylparaben, methylparaben, n-propylparaben, and ethyl paraben.
Parabens are used in cosmetics and other personal care products, including soaps and shampoos, as an anti-microbial preservative. Previous studies showed that parabens can be found in over 40% of rinse-off products (shampoos and conditioners, body wash, and face cleaners). Parabens are also found in leave-on cosmetics such as lotions and lipsticks, with methylparaben being the most abundant. Recent studies showed that some parabens can act as weak estrogen mimics. This finding, coupled with a 2004 study that found parabens in the breast tissues of women with breast cancer, raised concern about their ability to cause cancer. After scientific review, parabens are still considered safe for use in personal care products by the FDA, but certain types of parabens have been banned in the EU.
The study showed that methylparaben was the most prevalent paraben in both urine and breast milk samples. Methylparaben levels in breast milk were 30 times lower than levels in urine samples. On average, the highest levels of parabens were found in urine samples collected during the morning hours (from 8am until noon) with the lowest levels seen in the evening (from 6pm to midnight). The researchers believe that this is due to women using more cosmetics and personal care products in the morning hours.
Researchers also compared paraben levels in urine between women who used different amounts of personal care products. Women were classified as low users (0-5 products in a 24 hour period), medium users (6-9 products), or high users (10-14 products). When comparing different types of users, medium users had 21% higher levels of methylparaben in their urine when compared to low users, and high users had 161% more methylparaben than low users.
The researchers also found much higher parabens levels when comparing women who did not report using a specific product versus those who did report using a product. For example, women who reported using lotion had 99% more methylparaben in their urine than women who did not use lotion. However, some products, such as oral care products, led to variable paraben levels that did not clearly show an increase with increased usage. This could be due to study participants forgetting to log certain items or differences in how the women used each product.
Paraben levels measured in breast milk did not demonstrate a clear connection to personal care product use. Further analysis showed an increase in methylparaben levels in breast milk in women that reported using eye make-up. However, the magnitude of increase is small, strongly varies between study participants, and is found in only a small subset of the study group.
Paraben levels in urine samples are lower than what was reported in other studies from the US, Spain, and Puerto Rico. This may be due to differences in the types and amounts of personal care product used among different socioeconomic groups. Other studies also found that women are more likely to have higher urinary paraben levels than men, which the researchers believe is due to women using more personal care products.
Parabens are 10,000 times less potent than natural estrogen. Parabens are also far less estrogenic than natural phytoestrogens like daidzein, which is found in soy. Epidemiologists have yet to find any associated cancer risks linked to phytoestrogen consumption, so the chance that an estrogen as weak as parabens will cause harm is extremely unlikely.
Critics of the 2004 breast cancer study which reported that parabens were present in breast cancer tissue point out several flaws with the findings. Researchers did not measure paraben levels in non-cancerous tissues, making it impossible to assign any blame to parabens in causing breast cancer. Parabens also have a very short half-life, which means that these chemicals do not remain in the body for very long and are rapidly excreted.
Concerns about paraben safety led many cosmetics companies and consumers to seek out paraben-free alternatives. Regulators are still working to ensure that parabens are safe for consumer use but the data available now seem to point to parabens being of little concern.
What are microplastics?
The term “microplastics” refers to plastic and polymer debris with a diameter ranging from one micrometer up to five millimeters. This range of sizes includes debris that is smaller than the width of a human hair up to pieces that are as large as a pebble. Microplastics can form when larger plastic waste, such as drink bottles, break down into smaller chunks. Another source of microplastics are ‘microbeads’, or small pieces of plastic that are sometimes added to personal care products. Certain brands of exfoliating face cleansers or toothpaste have microbeads in them.
How do they get into the environment?
While personal care products are one source of microplastics, their use in cosmetic products is starting to be phased out. Microbeads are now banned in products made in the US and the UK is committed to implementing a ban by October 2017. There is currently no ban in the EU but the trade body Cosmetics Europe is encouraging its members to phase out microbeads by 2020.
The primary source of microplastics in the environment comes from the physical break-down of plastic waste. The amount of plastic generated each year has increased by a factor of four from 2004 to 2014, and it is predicted that by 2050 we could be making up to 33 billion tons of plastic per year. Because many of these plastic products are for short-term use, like product packing materials or single-use packaging, a large amount of plastic will be disposed of shortly after use.
Plastic is so used because of its durability. Larger pieces of plastic such as bottles and containers break down into smaller pieces, but these small pieces never truly degrade. Unless plastic waste is incinerated, it will continue to cycle through the environment. Because of this, microplastics and plastic litter can be found in a wide range of places: parks, prairies, forests, rivers, lakes, estuaries, coastal areas, the open ocean, and even deep sea sediments.
Why are scientists concerned?
Once microplastics enter the environment, plastics are eaten by animals, especially fish and birds. Recent studies showed that up to 90% of all seabirds have eaten plastic, and plastic could even be found in over half of the world’s sea turtle population. Many plastic pieces can simply be ejected from the body as waste, but too much plastic can cause serious harm to animals. Larger microplastic pieces can cause physical damage to an animal, such as internal cuts and bleeding, inflammation, and lower energy levels from consuming too much inedible and indigestible material.
The smallest pieces of microplastic will be eaten by animals such as diatoms, copepods, and brine shrimp, while larger pieces are consumed by shellfish, starfish, crabs, and fish such as catfish, perch, and trout. Smaller pieces eaten by animals lower on the food chain can then build up over time as these animals are eaten by larger predator species, causing microplastics to remain and even increase over time through the food chain.
An additional concern with animals eating microplastics comes from the chemical additives included in many plastic products that can be toxic. Certain chemicals are added to plastics for increased elasticity or rigidity, including bisphenol A, phthalates, polybrominated diphenyl ethers, and metals. Unlike the plastic polymers these chemicals are added to, additives are not as stable and can break apart from the plastics. Even if a fish or a mussel is unharmed by eating small pieces of plastic, the toxic chemicals attached to the plastic can get into the animal and cause serious toxic damage.
Should I be concerned?
Because plastics are so widespread in the environment and are known to be consumed by a large number of animals, scientists worry that traces of microplastics can be found in humans. This field of research is still growing, however, and there haven’t yet been any large-scale studies. Scientists are interested in looking at microplastic levels in humans and determining if differences in seafood consumption correspond with microplastic levels in the body.
But because this field is still new, there is a lot we still don’t know about microplastics. Many of the uncertainties are around the exact amount of microplastics that fish (and humans) might eat. This uncertainty comes from the fact that it is difficult to quantify the amount of plastic when there is such a broad range of sizes and shapes. Microplastics also represent a wide range of materials, all of which have different added chemicals, making it more of a challenge to determine what, exactly, we could be potentially exposed to.
Research progress is being made across the world to help answer these questions. A recent review highlighted the results of over 80 studies in aquatic environments which looked at both the distribution of plastic waste and the impacts of microplastics on animals and plants. The authors also identified ‘hot spots’ of microplastic pollution across the world. Other questions that scientists are working to answer will help policymakers determine the best course of action on national and international levels. These questions include how microplastics move in the environment, what types of polymers are the most common, and how ecosystems as a whole are affected by microplastics.
What can I do?
Using less plastic is a small yet simple start towards solving part of the problem. If you live in a country that does not ban microbeads in cosmetics, see if your current personal care products have added microplastics—and if they do, explore alternative products instead.
Local recycling and plastic reduction efforts have also been effective at decreasing plastic waste. In San Jose, CA, a 2012 plastic bag ban reduced the amount of plastic waste in the city by up to 89%. Keep a reusable bag with you while shopping and promote similar shopping initiatives in your own community.
If you want to become proactive in plastic waste reduction efforts in the US, NOAA maintains a list of clean-up events, teaching guides, and resources for recreational users as part of its Marine Debris program. NOAA is also the government organization in charge of awarding research grands, education, and clean-up efforts around microplastics and marine debris—so let your congressional representatives know that you support NOAA and don’t want their efforts to be hindered by budget cuts or government scientist gag orders.
This week on the Tox City Tribune, we’re offering an open letter that you can amend and send to your state’s congressional representatives. This week we are tackling a bill proposed in the House of Representatives: H.R.861-To terminate the Environmental Protection Agency. We wrote this letter as a way to talk directly to members of the current US Congress about the dangers of blindly rolling back legislation that could seriously harm environmental health and could also lead to severe impacts on our own health.
At the end of the letter we’ve provided links and resources where you can find relevant local information about the EPA’s work in the state where you live. This letter can be amended and sent to any of your local representatives, not just the ones who have sponsored or co-sponsored this bill (which currently includes Rep. Thomas Massie of Kentucky, Rep. Steven Palazzo of Mississippi, and Rep. Barry Loudermilk of Georgia).
We hope that this open letter can help voice the concerns for Americans who do not take attacks on the USEPA lightly. We also hope that this type of engagement can provide a new perspective about the importance of environmental protection to the conservative representatives who seem to doubt its usefulness. If you have questions, please get in touch!
Dear Rep. Matt Gaetz,
My name is Erica Brockmeier and I am a Florida voter who is passionate about our beautiful state. I earned my PhD in Toxicology from the University of Florida in December 2013. My project was supported by a graduate research fellowship from the US EPA and focused on the impacts of paper mill effluents on local fish populations in the Florida panhandle. Part of my dissertation focused on Florida’s ecosystems was published and is available to read through open access.
It’s my love of Florida and my concern for its unique and fragile ecosystems that motivates my letter to you. I am concerned with H.R.861 because of what this bill will mean for environmental and human health and for the landscapes and resources that make our country and our state wonderful places to live.
Our country is a vastly different place than it was in 1970 when the EPA was first enacted by President Nixon. Toxic pesticides like DDT were sprayed without thought of consequence, our gasoline was filled with lead, and the Cuyahoga River in Ohio was so polluted that it actually caught on fire (you can read more stories and see pictures here. Thanks to a government administration that recognized the importance of protecting environmental (and subsequently human) health, the US EPA was established to consolidate efforts to research, monitor, and establish rules for the safe use and disposal of chemicals.
The US EPA is also in charge of developing long-term clean-up plans for polluted sites as part of the 1980 Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). In Florida there are 52 Superfund sites, 4 of them located in Escambia county*. The US EPA is responsible for managing the cleanup of these sites and works to make them usable and safe for residents, visitors, and local wildlife.
There has been a lot of political discussion about the pitfalls of over-regulation while forgetting the economic benefits of many of these laws. Government regulations managed by the US EPA such as the Clean Air Act directly enhance our country’s economic well-being through an increased numbers of jobs in the engineering, construction, and manufacturing sectors. All of these benefits come at very low cost to the industries they are regulating. For example, data from 2005 showed that less than 1% of the revenue generated by US manufacturers was required for pollution control.
Environmental regulations also protect Americans and the places that make our country truly great. The US EPA estimated that amendments made to the clean air act in 1990 saved over 160,000 lives and prevented 86,000 emergency room visits in 2010 alone. The US EPA was also present during the 2010 Deepwater Horizon oil spill and helped gulf coast areas by collecting emergency data and ensuring sure that beaches and waters were safe for wildlife. The EPA’s efforts were also crucial for ensuring that clean-up efforts after the spill made Florida beaches ready to be enjoyed by the 20 million Florida residents and the 90 million tourists who visit our state every year.*
While it is important for our government to work towards decreasing unnecessary legislations and government bureaucracy, casting aside the efforts of an entire federal agency will put the lives and health of American people at risk by opening up our environment to inexcusable damage. Nearly 50 years ago our government, led by a Republican president, had the foresight to recognize the importance of a clean environment for the American people. Our founding fathers also established our country on the foundations of basic human rights including “Life, Liberty, and the Pursuit of Happiness.” The first of these rights is life. The right to live as an American citizen also includes the right to live life to the fullest: breathing clean air, drinking safe water, and protecting our country’s natural resources for future generations of Americans.
Part of living the American Dream also involves the opportunity to enjoy the incredible natural places that make our nation truly great, especially our incredible national parks and the landscapes and ecosystems that existed since before we were a unified nation. These great American places need as much protection as the American people. And protecting them, as well as ourselves, is a rewarding legacy we can leave for future generations, and justifies the EPA’s existence. Our founding fathers and the founders of the EPA shared a common vision that provides the opportunity for a life well-lived for every American. Clean air, drinkable water, and protection from harmful chemicals enable us all to achieve this American dream.
The problems that we’ll face as a nation in the next 50 years will be more challenging than when the EPA was first brought to life. The issues will not be as obvious as rivers on fire or skies full of smog but can come from chemicals that haven’t been produced yet, or by future contaminations and spills incidents that go undetected, such as the contamination of drinking water in Flint, Michigan last year.
Because our country still has a long ways to go for ensuring that our land is safe and clean for everyone, I would encourage you to remove your support from H.R.861 and re-focus your efforts on something that would provide more benefit to the American people. The US EPA is fundamental for ensuring that Americans have the right to Life, Liberty, and the Pursuit of Happiness, and throwing away this agency would do a significant disservice to the rights and well-being of all American citizens.
I would also encourage you and your fellow representatives to support an EPA budget that works for supporting the health of the American people. Recent news articles state that proposed budget cuts from the current administration to the EPA are up to 40% of the current budget. Because of this Agency’s crucial importance in protecting environmental quality, any broad budget cuts that are not thoroughly evaluated have the potential to damage our country and the health of the American people significantly. As one of the cuts is potentially for the program which supported my graduate education, I would also like to vouch personally for the benefits of these types of EPA programs. I would not be in the position I am today without the financial support from the EPA STAR program.
I am thankful to be part of such a beautiful state in the USA, and I hope that my fellow citizens can continue to enjoy the beautiful landscapes, pristine ecosystems, and enriching environments that attract so many visitors to our state every year.
Erica K. Brockmeier, Ph.D.
Italicized opening paragraph: Please replace with your own personal background, including why you feel that protecting environmental health is important.
Insert 1: For information on superfund sites in your state/local area, please visit this website.
Insert 2: If you know of a recent or historical environmental disaster in your area, include a brief description of the incident here. If you aren’t sure where to start, you can click here.
Italicized pentultimate paragraph: Please replace with a personal connection you might have to an EPA program, office, activity, etc, or simply a reason why you feel that environmental health should be a priority for our government representatives.
Wastewater treatment improvements help local fish populations recover from chemical exposure in Canada
A new field study reports a decrease in the number of abnormal intersex fish living downstream of Kitchener, Ontario after effluent processing changes were made at the town’s wastewater treatment plant.
The article, published in the February 7th issue of Environmental Science and Technology, show how changes made at the Kitchener wastewater treatment plant lowered the number of rainbow darter with reproductive abnormalities. The plant upgrade included the addition of a nitrifying procedure, which reduced the effluent’s estrogen levels.
Researchers from the University of Waterloo, the Ontario Ministry of Climate Change, and Environment Canada collected fish from the Grand River both before and after processing changes. Fish were also collected from a clean upstream site and from a site downstream of another wastewater treatment plant. This plant in Waterloo did not undergo any processing changes.
Intersex fish have the reproductive tissues of both males and females. In male fish, intersex is measured as the number of egg cells in the testes. Intersex fish were first discovered in 2003 by USGS researchers in West Virginia. More studies have since found large numbers of intersex fish across North America. Exposure to hormones such as natural and synthetic estrogen is thought to be the culprit for these intersex characteristics.
This study looked for the presence of intersex in a small freshwater fish species, the rainbow darter, from 2007 through 2015. Effluent processing changes were made in mid-2012. Darters collected from the clean site had low numbers of intersex (less than 20%) and the levels did not change during the study. Downstream of the Kitchener plant, as many as 100% of fish sampled were intersex before 2012. The level of intersex in these fish dropped by more than 75% by the end of 2015. The number of intersex fish was consistent at the site where there were no effluent processing changes.
The estrogen levels were measured before and after plant upgrades. Estrogen levels in the Kitchener wastewater treatment plant decreased after 2012. There were also lower levels of pharmaceuticals, including ibuprofen, naproxen, and carbamazepine.
Estrogen exposure isn’t limited to intersex in fish. A lake-wide study found that estrogen exposure could wipe out entire fish populations. Male fish exposed to estrogens also have lower testosterone levels and smaller testes.
Treatment changes made at the Kitchener plant included nitrification of the activated sludge. This involves adding bacteria that convert ammonia to nitrogen. Previous studies showed that nitrification of sludge could reduce the amount of hormones in effluents, but this is the first study to show positive impacts on fish populations. Since rainbow darter can live up to five years, the population’s recovery over the three year period shows that intersex is not permanent.
One confounding result from this study is the increase in effluent nitrogen levels. While ammonia, pharmaceuticals, and estrogen levels decreased, nitrates increased to 20 mg/L. The EPA recommends that nitrate levels in drinking water be no higher than 10 mg/L. Higher nitrogen levels promote algae overgrowth that can lead to decreases in oxygen, a process known as eutrophication. Future work at this site will need to ensure that nitrogen levels are not causing other types of environmental damage.
Welcome to the next chapter of Science with Style! Every other week we'll highlight research, policies, and news related to toxicology and environmental/public health. You can follow us on twitter at @ToxCityTribune for more articles and updates around this topic. Let us know what other research highlights or science news you'd be interested to see here!
New findings from a human cell culture study show that aerosols from e-cigarettes can cause cell death and oxidative stress but at lower levels than standard cigarettes.
The article from the December issue of Toxicological Sciences looked at extracts from four brands of e-cigarettes to see if the aerosols could increase reactive oxygen species levels. Reactive oxygen species, also known as free radicals, cause cellular stress and are known by-products of cigarette smoke.
The study, done at Tulane University, compared free radical levels between standard cigarettes fumes and e-cigarette aerosols. Researchers found that aerosols from e-cigarettes increased the number of free radicals in cells. However, the level of free radical increase only reached 50% of the increase caused by standard cigarette fumes. E-cigarette aerosols also caused cell death and DNA damage but at lower levels when compared to standard cigarettes.
Free radicals are highly-reactive molecules that can build up in the body during exposure to toxic chemicals. High free radical levels cause oxidative stress and are linked to cardiac disease and cancer. Consuming fruits and vegetables with anti-oxidants, such as Vitamin C, is a way to protect against the damage caused by free radicals.
This study also found that anti-oxidant treatment could prevent free radical increases. Certain brands of e-cigarettes already include anti-oxidants in their aerosol formulation. It's not currently known if including vitamins in aerosol can actually prevent free radical levels from increasing during e-cigarette use.
E-cigarettes work by creating very small particles to deliver nicotine in aerosol form, but the exact components of these aerosols are unknown. E-cigarette use is linked to cardiovascular disease but the overall risks of chronic e-cigarette use are still not well-understood.
The results of the study showing that free radical levels are lower in e-cigarette aerosols when compared to standard cigarettes. These increases were mitigated by anti-oxidant treatment in cells, findings that may seem promising to e-cigarette advocates. But an increase in free radicals, however small, is still cause for concern because of links between free radicals and cancer.
The use of e-cigarettes and tobacco alternatives are currently on the rise. A large number of students under 18 are using e-cigarettes before they switch to standard cigarettes. A survey of high school students found that many believed e-cigarettes to be a safe alternative to cigarettes, showing a lack of understanding about the risks of e-cigarettes among younger users.
This study shows that e-cigarettes may have harmful effects, even if the risk is lower than for standard cigarettes. These findings also show a need for more thorough studies of the clinical risks of long-term e-cigarette usage.