“]

A view of the city from the top of the conference hotel, Gothia Towers. [Original image of poster session deleted 14-6-09

Among the comments from the four wrap-up speakers, Marco Vighi of the University of Milano Bicocca (Italy) made one I quite liked, in his summary of ecotoxicology: “Nature is not only more complex than we think. It is more complex than we *can* think,” he said. Vighi underscored the move to include more “reductionist” approaches while also including more “ecological realism,” and paying attention to the indirect effects across the many heirarchies — molecules, cells, individual organisms, and populations, communities, ecosystems — while doing ecotoxicology. Researchers seem to be bringing the ecology more strongly to bear on the field.

Usually I would report everyone’s summaries (and I might write some of the other three up later), but for now, I’d like to mention a few of the interesting ideas I heard in the hallways, talks, and posters I saw these past few days.

• A few of the SETAC governing members told me a bit about efforts at SAICM (the international chemicals management body), and I was interested in the teaching sessions they held to build people infrastructure in Africa for regulation. Yogi Naik of the National University of Science and Technology in Zimbabwe talked a bit more about this on Monday at the EMERCHEM afternoon session. Some chemicals, he said, that the developed world knows well have yet to raise alarms, despite their widespread presence in Africa. “Melamine wasn’t a problem [in Africa] until it hit the developed world,” he said, referencing the melamine scare in foodstuffs from China last year.
• Mixtures appeared in both talks and posters — simple combinations for now, it seems, in an effort to figure out whether additive or synergistic effects are at play.  I think this area of research is still at the beginning, but I was impressed at the number of platforms connected to it, for pharmaceuticals and pesticides.
• Endocrine disruptors, pollution in polar marine and terrestrial settings, perfluorinated compounds, and other topics that are the bread-and-butter of this meeting were all here, with one (new-to-me-at-least) compound added to the mix: siloxanes.  Things are heating up for this persistent compound, which shows up in personal care products like deoderants and hair gels.  Canada is working on how to manage it at the moment, and the EU is going to decide whether to ban it or not next year.  Some of the toxicity (or lack thereof?) was reported at this meeting.
• Another ongoing discussion that continued at this SETAC Europe meeting swirled around alternatives to animal testing.  I heard several instances where speakers mentioned choosing the right animal for the right toxic for testing, and of course, lots on microarrays and other in vitro results.  I confess that I still find this challenge a bit overwhelming — almost as overwhelming as thinking about how to tackle nanomaterials in their many forms, let alone the normal-sized chemicals that need to be tested in the near future for REACH, for example.
• I missed the session on life-cycle assessment and nanomaterials, and I was keen to hear about LCA and sustainability.  Maybe next meeting I’ll make it to those sessions!

Despite my feeling that this year’s SETAC Europe meeting was smaller than usual (I have not checked the numbers), I saw a bunch of interesting stuff presented.  I can’t report all of it here, but hope to report some of it later, as these scientists’ results start showing up in the peer-reviewed literature.

So, until the next meeting, whether it’s the SETAC North America meeting in New Orleans or the next European conference in Seville, “orevwa” and chao!

Mapping out ecotoxicology across many disciplines.

The plenary talk today, the third day of the SETAC Europe meeting, was delivered by Tinka Murk of Wageningen University (The Netherlands).  I’ve interviewed Murk before, and I think she usually puts together the women’s lunch at SETAC Europe meetings.  I don’t think she did this year.

Instead, she gave a great plenary that was like an ecotoxicology course jammed into 45 minutes or so.

I am not an ecotoxicologist, but I think some of her pointers are universal:  Be an expert, but don’t forget to consult colleagues, because you cannot know everything. Think outside your specialty:  if you are a soils scientist, she said, look at marine sciences too, as the data collected in one environmental setting often can inform another. You also have to learn enough to know how to look at a problem in the right way.

For ecotox, that could mean knowing which species to monitor, how to monitor them, and whether or not an individual organism’s response to a contaminant or other stressor can be translated to a whole population or not.  Murk gave some really interesting examples for each of the points she made, including some ongoing experiments with European eel in a lab in the Netherlands (doi:10.1016/j.aquatox.2009.01.004).

Researchers have created a current with water flowing through a tube within a tube.  Eels swim along a steady current of water recycled in a loop, which makes them think they are migrating to their breeding site in the Sargasso Sea.  An experiment running the eels 800 km in a month showed that as they dropped their lipid fat on the long haul, the PCBs were concentrated into their remaining fat deposits.  The implications for their young at the end of their journey are a large “gift” of PCBs, something that happens with female whales and their offspring (http://pubs.acs.org/doi/abs/10.1021/es072611y), among other animals.

Chemistry, toxicology, ecology — the works.  You have to think of everything, which makes ecotox complex and difficult, and very worth doing, Murk said.

It’s sort of like tackling the talks and posters at a SETAC meeting –  I’ll highlight some of the ones I saw throughout the week tomorrow, along with the wrap-up session at meeting’s end.

A Thai farmer applies pesticides to her tangerine orchard. Her house is just behind the photographer, Michiel Daam.

I’ll tell a few of the high points that I remember from talking to him for a few minutes in the afternoon.  From one video in particular, I remember a woman mixing pesticides in a dinghy that was almost at the same water level as the irrigation channel she was standing in.  She then wrapped her head and mouth with her scarf, securing it on her head with her traditional conical straw hat; loaded the mixture from the boat into a spray can, and proceeded to spray her tangerine crop, several feet above her on the banks.  You could see the spray floating away — above her head, into the channel, into her neighbor’s field… everywhere.

“Say 80%, say 100% drifted away,” Daam told me. Only 0.1% reaches the target organism. The rest reaches the woman, her neighbors, the irrigation water, her house, the organisms that live around her — everything but the bugs she’s trying to prevent from reaching her crop.

Daam followed one farmer down his row crop, videotaping the application. He came back covered in pesticides. “Didn’t have problems with mosquitoes for three days,” he says, half-laughing.

Daam has work with one of his PhD advisors, Paul van den Brink, on teaching people how to use these pesticides without overapplying and without exposing themselves, but it’s tough.  (van den Brink does this from Asia to South America and elsewhere.)  Daam did the ecotoxicological part of the work, he says, but while in the field, he noticed that people can be taught all these things, but in the end, they want desperately to have a crop to sell.  That means that some of these moderative actions may have no impact in the end.

Barnacles are one of the pests targeted by preventive TBT paints on ship hulls. Courtesy of Wikipedia.

Environmental scientists talk about persistence in terms of whether a compound sticks around. In the case of the tributyltin (TBT), it’s also persistent in a slightly different way, mostly because of human behavior.

The compound in paints that keeps ships barnacle-free seems to keep showing up in marine sediments in Sweden’s harbors, according to Britta Eklund of ITM in Stockholm. She reported yesterday that Swedish harbors large and small, as well as “natural” and human-occupied, still have high levels of the compound, which causes deformation in some see creatures and acts as en endocrine disruptor in mussels and barnacles.

The global ban on TBT is only a year old, but small craft (<25 m) have been banned from being painted by the stuff for decades in Sweden. And yet the TBT Eklund is finding is recent — in the top 2 cm of the sediments and in marinas with ship-washing setups. Perhaps there is stockpiling, or perhaps layers of new paint without TBT are peeling off to reveal the chemical in older paint below. I wrote on Monday that Tom Hutchinson has been seeing communities bounce back after the ban on the paints, and a poster in today’s sessions shows some of the same. But TBT isn’t quite gone yet, it seems.

It’s another example of how long the chemicals we produce stay around. One of the other talks I hit yesterday was about layers of activated carbon that scientists put down on the seafloor, to see how well the carbon absorbs such toxic contaminants as dioxins or PAHs like pyrene.  Activated carbon can be spread over large areas and absorbs contaminants for years — but one questioner in the audience asked, what’s the impact of leaving this stuff around for awhile?  You have to consider whether the carbon would continue to absorb contaminants for long enough, and what else it might do to the environment to which it’s added.

That question also made me think about nanomaterials, one of the “emerging” topics that dominates several sessions of SETAC this meeting (and past meetings as well).  I’ve written about nanomaterials as both environmental solutions and possible disasters.  One key that’s missing is how to track these tiniest of particles in the environment to see what they actually do. I heard yesterday about some new methods to do just that — a task that might be akin to finding a particular piece of hay tied in knots in a haystack.  And while the questions people are asking about nanomaterials may still sound basic — including whether they are available for uptake by microbes, another talk I heard yesterday — answers seem to be coming…

It’s all a question of persistence, a part of the whole equation of whether or not a compound will be a risk (and what I think of as the first of three alarm bells. The other two are bioaccumulation, or whether organisms will take up a compound and incorporate it into their tissues, and toxicity, whether a compound is detrimental in some way — which all together make a PBT sandwich).

You also have to be persistent to attend SETAC.  It’s a small meeting, relative to some, but overwhelming, and to some extent, the people attending it are interested in almost everything being presented here.  That explains why some of us are running from one side of the convention hall to the other to catch talks in parallel sessions.  With so much to choose from, it’s almost overwhelming…

An organically warped Swedish ship sailing through the Gothenburg conference center.

“Protecting ecosystem health: facing the challenge of a globally changing environment” — that’s this year’s theme for the European meeting of SETAC. Climate change is on the agenda, as are nanomaterials, but no sign of the human health session that was at the last meeting. Nevertheless, protecting human health lurks behind protecting ecosystem health, as evidenced by a few of the talks I heard today.

Those included an excellent overview of epigenetics by Juliette Legler of VU University. She highlighted some of the recent literature on epigenetics as it applies to environmental issues, and ended up circling back to human health. Her group is starting a study called OBELIX (inspired by the comics character from Asterix & Obelix), to look at the environmental effects that might be tweaking gene expression etc., leading to obesity in people.  Interesting stuff that’s not quite accepted, it seems — one audience member commented that reviewers don’t quite want epigenetics in environmental science yet, if I understood correctly.

But obviously environmental impacts affect at least the next generation, if not the third, particularly when you are talking about endocrine disruption. Among others, Henk Bouwman presented in a session about emerging chemicals in the developing world, following up on research he recently published with Henrik Kylin in EHP (http://www.ehponline.org/docs/2009/0900605/abstract.html). They continue to document DDT in breast milk in women in South Africa. The results include hypospadias in baby boys and undescended testes, among other effects.

But we are also improving the situations that we’ve created in applying chemicals to pests — one story I’d like to write sometime is about the turnaround in using TBT in ship paint, to control barnacles and other creatures from attaching themselves to seagoing vessels. That old paint had endocrine disrupting effects on these animals’ offspring. The EU seems to have successfully phased out their use, and populations of some critters are bouncing back, Tom Hutchinson mentioned at one point in his plenary talk this afternoon.

Hutchinson, who used to be at AstraZeneca and is now at the Plymouth Marine Laboratory (UK), hit a bunch of high points in the recent ecotoxicology literature. He mentioned a paper on MistraPharma, which catalogs possible genetic effects of pharmaceuticals in the environment, in an attempt to forecast impacts — it received the AstraZeneca award for best paper in risk assessment (DOI 10.1021/es8005173; I wrote about in ES&T last year). This kind of work, along with other model animals, is tricky — some “small model” systems like zebrafish can be useful for figuring out toxic endpoints, but can also be misleading, depending on the biomarkers chosen, he commented.

One thrust of Hutchinson’s talk that is sticking with me centered on the confluence of increasing human populations and pollution on coastlines. At one point he commented that there are more and more of us on this planet, and with more people, we use more drugs that end up in the environment.  He also alluded to another impact of climate change and human activities — the acidification of the oceans.

I’m part of that problem, I guess — I’m pretty jetlagged from two long flights yesterday, which I’m sure put out a lot of carbon.  (I wonder how people coming from the far side of North America gave talks today.)  And this is just the beginning of the meeting!  More tomorrow…

Flying into the city, my plane crossed over granite cliffs surrounding placid lakes and a landscape blanketed by northern forests — it looked like the Algonquin, for any of you who have gone canoeing in that Canadian park.  Absolutely gorgeous, and looking at it made me think of acid rain, mercury cycling, persistent organic pollutant uptake by forests, and the other sorts of things I might hear about at this meeting this week.

More to come soon!

The view outside the conference hotel includes the Liseberg amusement park. I took this photo at around 8 pm the first day of the conference, 1 June, and look how light it is! Ah, summer in Sweden!